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2709 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Mykyta Yatsenko
|
7b30c296af |
libbpbpf: Check bpf_map/bpf_program fd validity
libbpf creates bpf_program/bpf_map structs for each program/map that user defines, but it allows to disable creating/loading those objects in kernel, in that case they won't have associated file descriptor (fd < 0). Such functionality is used for backward compatibility with some older kernels. Nothing prevents users from passing these maps or programs with no kernel counterpart to libbpf APIs. This change introduces explicit checks for kernel objects existence, aiming to improve visibility of those edge cases and provide meaningful warnings to users. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240318131808.95959-1-yatsenko@meta.com |
||
Alexei Starovoitov
|
10ebe835c9 |
libbpf, selftests/bpf: Adjust libbpf, bpftool, selftests to match LLVM
The selftests use to tell LLVM about special pointers. For LLVM there is nothing "arena" about them. They are simply pointers in a different address space. Hence LLVM diff https://github.com/llvm/llvm-project/pull/85161 renamed: . macro __BPF_FEATURE_ARENA_CAST -> __BPF_FEATURE_ADDR_SPACE_CAST . global variables in __attribute__((address_space(N))) are now placed in section named ".addr_space.N" instead of ".arena.N". Adjust libbpf, bpftool, and selftests to match LLVM. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20240315021834.62988-3-alexei.starovoitov@gmail.com |
||
Linus Torvalds
|
1bbeaf83dd |
perf tools changes for v6.9
perf stat
---------
* Support new 'cluster' aggregation mode for shared resources depending on the
hardware configuration.
$ sudo perf stat -a --per-cluster -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
S0-D0-CLS0 2 85,051,822 cycles
S0-D0-CLS0 2 73,909,908 instructions # 0.87 insn per cycle
S0-D0-CLS2 2 93,365,918 cycles
S0-D0-CLS2 2 83,006,158 instructions # 0.89 insn per cycle
S0-D0-CLS4 2 104,157,523 cycles
S0-D0-CLS4 2 53,234,396 instructions # 0.51 insn per cycle
S0-D0-CLS6 2 65,891,079 cycles
S0-D0-CLS6 2 41,478,273 instructions # 0.63 insn per cycle
1.002407989 seconds time elapsed
* Various fixes and cleanups for event metrics including NaN handling.
perf script
-----------
* Use libcapstone if available to disassemble the instructions. This enables
'perf script -F disasm' and 'perf script --insn-trace=disasm' (for Intel-PT).
$ perf script -F event,ip,disasm
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffa9839d25 movq %rax, %r14
cycles:P: ffffffffa9cdcaf0 endbr64
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffaa401f86 iretq
cycles:P: ffffffffa99c4de5 movq 0x30(%rcx), %r8
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffaa401f86 iretq
cycles:P: ffffffffa9907983 movl 0x68(%rbx), %eax
cycles:P: ffffffffa988d428 wrmsr
* Expose sample ID / stream ID to python scripts
perf test
---------
* Add more perf test cases from Redhat internal test suites. This time it adds
the base infra and a few perf probe tests. More to come. :)
* Add 'perf test -p' for parallel execution and fix some issues found by the
parallel test.
* Support symbol test to print symbols in given (active) module:
$ perf test -F -v Symbols --dso /lib/modules/$(uname -r)/kernel/fs/ext4/ext4.ko
--- start ---
Testing /lib/modules/6.5.13-1rodete2-amd64/kernel/fs/ext4/ext4.ko
Overlapping symbols:
7a990-7a9a0 l __pfx_ext4_exit_fs
7a990-7a9a0 g __pfx_cleanup_module
Overlapping symbols:
7a9a0-7aa1c l ext4_exit_fs
7a9a0-7aa1c g cleanup_module
...
JSON metric updates
-------------------
* A new round of Intel metric updates.
* Support Power11 PVR (compatible to Power10).
* Fix cache latency events on Zen 4 to set SliceId properly.
Internal
--------
* Fix reference counting for 'map' data structure, tireless work from Ian!
* More memory optimization for struct thread and annotate histogram. Now,
'perf report' (TUI) and 'perf annotate' should be much lighter-weight in
terms of memory footprint.
* Support cross-arch perf register access. Clean up the build configuration
so that it can detect arch-register support at runtime. This can allow to
parse register data in sample which was recorded in a different arch.
Others
------
* Sync task state in 'perf sched' to kernel using trace event fields. The
task states have been changed so tools cannot assume a fixed encoding.
* Clean up 'perf mem' to generalize the arch-specific events.
* Add support for local and global variables to data type profiling. This
would increase the success rate of type resolution with DWARF.
* Add short option -H for --hierarchy in 'perf report' and 'perf top'.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Merge tag 'perf-tools-for-v6.9-2024-03-13' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Namhyung Kim:
"perf stat:
- Support new 'cluster' aggregation mode for shared resources
depending on the hardware configuration:
$ sudo perf stat -a --per-cluster -e cycles,instructions sleep 1
Performance counter stats for 'system wide':
S0-D0-CLS0 2 85,051,822 cycles
S0-D0-CLS0 2 73,909,908 instructions # 0.87 insn per cycle
S0-D0-CLS2 2 93,365,918 cycles
S0-D0-CLS2 2 83,006,158 instructions # 0.89 insn per cycle
S0-D0-CLS4 2 104,157,523 cycles
S0-D0-CLS4 2 53,234,396 instructions # 0.51 insn per cycle
S0-D0-CLS6 2 65,891,079 cycles
S0-D0-CLS6 2 41,478,273 instructions # 0.63 insn per cycle
1.002407989 seconds time elapsed
- Various fixes and cleanups for event metrics including NaN handling
perf script:
- Use libcapstone if available to disassemble the instructions. This
enables 'perf script -F disasm' and 'perf script --insn-trace=disasm'
(for Intel-PT):
$ perf script -F event,ip,disasm
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffa9839d25 movq %rax, %r14
cycles:P: ffffffffa9cdcaf0 endbr64
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffaa401f86 iretq
cycles:P: ffffffffa99c4de5 movq 0x30(%rcx), %r8
cycles:P: ffffffffa988d428 wrmsr
cycles:P: ffffffffaa401f86 iretq
cycles:P: ffffffffa9907983 movl 0x68(%rbx), %eax
cycles:P: ffffffffa988d428 wrmsr
- Expose sample ID / stream ID to python scripts
perf test:
- Add more perf test cases from Redhat internal test suites. This
time it adds the base infra and a few perf probe tests. More to
come. :)
- Add 'perf test -p' for parallel execution and fix some issues found
by the parallel test
- Support symbol test to print symbols in given (active) module:
$ perf test -F -v Symbols --dso /lib/modules/$(uname -r)/kernel/fs/ext4/ext4.ko
--- start ---
Testing /lib/modules/6.5.13-1rodete2-amd64/kernel/fs/ext4/ext4.ko
Overlapping symbols:
7a990-7a9a0 l __pfx_ext4_exit_fs
7a990-7a9a0 g __pfx_cleanup_module
Overlapping symbols:
7a9a0-7aa1c l ext4_exit_fs
7a9a0-7aa1c g cleanup_module
...
JSON metric updates:
- A new round of Intel metric updates
- Support Power11 PVR (compatible to Power10)
- Fix cache latency events on Zen 4 to set SliceId properly
Internal:
- Fix reference counting for 'map' data structure, tireless work from
Ian!
- More memory optimization for struct thread and annotate histogram.
Now, 'perf report' (TUI) and 'perf annotate' should be much
lighter-weight in terms of memory footprint
- Support cross-arch perf register access. Clean up the build
configuration so that it can detect arch-register support at
runtime. This can allow to parse register data in sample which was
recorded in a different arch
Others:
- Sync task state in 'perf sched' to kernel using trace event fields.
The task states have been changed so tools cannot assume a fixed
encoding
- Clean up 'perf mem' to generalize the arch-specific events
- Add support for local and global variables to data type profiling.
This would increase the success rate of type resolution with DWARF
- Add short option -H for --hierarchy in 'perf report' and 'perf top'"
* tag 'perf-tools-for-v6.9-2024-03-13' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (154 commits)
perf annotate: Add comments in the data structures
perf annotate: Remove sym_hist.addr[] array
perf annotate: Calculate instruction overhead using hashmap
perf annotate: Add a hashmap for symbol histogram
perf threads: Reduce table size from 256 to 8
perf threads: Switch from rbtree to hashmap
perf threads: Move threads to its own files
perf machine: Move machine's threads into its own abstraction
perf machine: Move fprintf to for_each loop and a callback
perf trace: Ignore thread hashing in summary
perf report: Sort child tasks by tid
perf vendor events amd: Fix Zen 4 cache latency events
perf version: Display availability of OpenCSD support
perf vendor events intel: Add umasks/occ_sel to PCU events.
perf map: Fix map reference count issues
libperf evlist: Avoid out-of-bounds access
perf lock contention: Account contending locks too
perf metrics: Fix segv for metrics with no events
perf metrics: Fix metric matching
perf pmu: Fix a potential memory leak in perf_pmu__lookup()
...
|
||
Kui-Feng Lee
|
c911fc61a7 |
libbpf: Skip zeroed or null fields if not found in the kernel type.
Accept additional fields of a struct_ops type with all zero values even if these fields are not in the corresponding type in the kernel. This provides a way to be backward compatible. User space programs can use the same map on a machine running an old kernel by clearing fields that do not exist in the kernel. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240313214139.685112-2-thinker.li@gmail.com |
||
Quentin Monnet
|
9bf48fa19a |
libbpf: Prevent null-pointer dereference when prog to load has no BTF
In bpf_objec_load_prog(), there's no guarantee that obj->btf is non-NULL
when passing it to btf__fd(), and this function does not perform any
check before dereferencing its argument (as bpf_object__btf_fd() used to
do). As a consequence, we get segmentation fault errors in bpftool (for
example) when trying to load programs that come without BTF information.
v2: Keep btf__fd() in the fix instead of reverting to bpf_object__btf_fd().
Fixes:
|
||
Andrii Nakryiko
|
2e7ba4f8fd |
libbpf: Recognize __arena global variables.
LLVM automatically places __arena variables into ".arena.1" ELF section.
In order to use such global variables bpf program must include definition
of arena map in ".maps" section, like:
struct {
__uint(type, BPF_MAP_TYPE_ARENA);
__uint(map_flags, BPF_F_MMAPABLE);
__uint(max_entries, 1000); /* number of pages */
__ulong(map_extra, 2ull << 44); /* start of mmap() region */
} arena SEC(".maps");
libbpf recognizes both uses of arena and creates single `struct bpf_map *`
instance in libbpf APIs.
".arena.1" ELF section data is used as initial data image, which is exposed
through skeleton and bpf_map__initial_value() to the user, if they need to tune
it before the load phase. During load phase, this initial image is copied over
into mmap()'ed region corresponding to arena, and discarded.
Few small checks here and there had to be added to make sure this
approach works with bpf_map__initial_value(), mostly due to hard-coded
assumption that map->mmaped is set up with mmap() syscall and should be
munmap()'ed. For arena, .arena.1 can be (much) smaller than maximum
arena size, so this smaller data size has to be tracked separately.
Given it is enforced that there is only one arena for entire bpf_object
instance, we just keep it in a separate field. This can be generalized
if necessary later.
All global variables from ".arena.1" section are accessible from user space
via skel->arena->name_of_var.
For bss/data/rodata the skeleton/libbpf perform the following sequence:
1. addr = mmap(MAP_ANONYMOUS)
2. user space optionally modifies global vars
3. map_fd = bpf_create_map()
4. bpf_update_map_elem(map_fd, addr) // to store values into the kernel
5. mmap(addr, MAP_FIXED, map_fd)
after step 5 user spaces see the values it wrote at step 2 at the same addresses
arena doesn't support update_map_elem. Hence skeleton/libbpf do:
1. addr = malloc(sizeof SEC ".arena.1")
2. user space optionally modifies global vars
3. map_fd = bpf_create_map(MAP_TYPE_ARENA)
4. real_addr = mmap(map->map_extra, MAP_SHARED | MAP_FIXED, map_fd)
5. memcpy(real_addr, addr) // this will fault-in and allocate pages
At the end look and feel of global data vs __arena global data is the same from
bpf prog pov.
Another complication is:
struct {
__uint(type, BPF_MAP_TYPE_ARENA);
} arena SEC(".maps");
int __arena foo;
int bar;
ptr1 = &foo; // relocation against ".arena.1" section
ptr2 = &arena; // relocation against ".maps" section
ptr3 = &bar; // relocation against ".bss" section
Fo the kernel ptr1 and ptr2 has point to the same arena's map_fd
while ptr3 points to a different global array's map_fd.
For the verifier:
ptr1->type == unknown_scalar
ptr2->type == const_ptr_to_map
ptr3->type == ptr_to_map_value
After verification, from JIT pov all 3 ptr-s are normal ld_imm64 insns.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/bpf/20240308010812.89848-11-alexei.starovoitov@gmail.com
|
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|
Alexei Starovoitov
|
79ff13e991 |
libbpf: Add support for bpf_arena.
mmap() bpf_arena right after creation, since the kernel needs to remember the address returned from mmap. This is user_vm_start. LLVM will generate bpf_arena_cast_user() instructions where necessary and JIT will add upper 32-bit of user_vm_start to such pointers. Fix up bpf_map_mmap_sz() to compute mmap size as map->value_size * map->max_entries for arrays and PAGE_SIZE * map->max_entries for arena. Don't set BTF at arena creation time, since it doesn't support it. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240308010812.89848-9-alexei.starovoitov@gmail.com |
||
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Alexei Starovoitov
|
4d2b56081c |
libbpf: Add __arg_arena to bpf_helpers.h
Add __arg_arena to bpf_helpers.h Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240308010812.89848-8-alexei.starovoitov@gmail.com |
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Masahiro Yamada
|
e2bad142bb |
kbuild: unexport abs_srctree and abs_objtree
Commit |
||
|
Alexei Starovoitov
|
d147357e2e |
libbpf: Allow specifying 64-bit integers in map BTF.
__uint() macro that is used to specify map attributes like: __uint(type, BPF_MAP_TYPE_ARRAY); __uint(map_flags, BPF_F_MMAPABLE); It is limited to 32-bit, since BTF_KIND_ARRAY has u32 "number of elements" field in "struct btf_array". Introduce __ulong() macro that allows specifying values bigger than 32-bit. In map definition "map_extra" is the only u64 field, so far. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240307031228.42896-5-alexei.starovoitov@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
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Eduard Zingerman
|
6ebaa3fb88 |
libbpf: Rewrite btf datasec names starting from '?'
Optional struct_ops maps are defined using question mark at the start
of the section name, e.g.:
SEC("?.struct_ops")
struct test_ops optional_map = { ... };
This commit teaches libbpf to detect if kernel allows '?' prefix
in datasec names, and if it doesn't then to rewrite such names
by replacing '?' with '_', e.g.:
DATASEC ?.struct_ops -> DATASEC _.struct_ops
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-13-eddyz87@gmail.com
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Eduard Zingerman
|
5ad0ecbe05 |
libbpf: Struct_ops in SEC("?.struct_ops") / SEC("?.struct_ops.link")
Allow using two new section names for struct_ops maps:
- SEC("?.struct_ops")
- SEC("?.struct_ops.link")
To specify maps that have bpf_map->autocreate == false after open.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-12-eddyz87@gmail.com
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Eduard Zingerman
|
240bf8a516 |
libbpf: Replace elf_state->st_ops_* fields with SEC_ST_OPS sec_type
The next patch would add two new section names for struct_ops maps.
To make working with multiple struct_ops sections more convenient:
- remove fields like elf_state->st_ops_{shndx,link_shndx};
- mark section descriptions hosting struct_ops as
elf_sec_desc->sec_type == SEC_ST_OPS;
After these changes struct_ops sections could be processed uniformly
by iterating bpf_object->efile.secs entries.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-11-eddyz87@gmail.com
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Eduard Zingerman
|
fe9d049c3d |
libbpf: Sync progs autoload with maps autocreate for struct_ops maps
Automatically select which struct_ops programs to load depending on
which struct_ops maps are selected for automatic creation.
E.g. for the BPF code below:
SEC("struct_ops/test_1") int BPF_PROG(foo) { ... }
SEC("struct_ops/test_2") int BPF_PROG(bar) { ... }
SEC(".struct_ops.link")
struct test_ops___v1 A = {
.foo = (void *)foo
};
SEC(".struct_ops.link")
struct test_ops___v2 B = {
.foo = (void *)foo,
.bar = (void *)bar,
};
And the following libbpf API calls:
bpf_map__set_autocreate(skel->maps.A, true);
bpf_map__set_autocreate(skel->maps.B, false);
The autoload would be enabled for program 'foo' and disabled for
program 'bar'.
During load, for each struct_ops program P, referenced from some
struct_ops map M:
- set P.autoload = true if M.autocreate is true for some M;
- set P.autoload = false if M.autocreate is false for all M;
- don't change P.autoload, if P is not referenced from any map.
Do this after bpf_object__init_kern_struct_ops_maps()
to make sure that shadow vars assignment is done.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-9-eddyz87@gmail.com
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Eduard Zingerman
|
8db052615a |
libbpf: Honor autocreate flag for struct_ops maps
Skip load steps for struct_ops maps not marked for automatic creation.
This should allow to load bpf object in situations like below:
SEC("struct_ops/foo") int BPF_PROG(foo) { ... }
SEC("struct_ops/bar") int BPF_PROG(bar) { ... }
struct test_ops___v1 {
int (*foo)(void);
};
struct test_ops___v2 {
int (*foo)(void);
int (*does_not_exist)(void);
};
SEC(".struct_ops.link")
struct test_ops___v1 map_for_old = {
.test_1 = (void *)foo
};
SEC(".struct_ops.link")
struct test_ops___v2 map_for_new = {
.test_1 = (void *)foo,
.does_not_exist = (void *)bar
};
Suppose program is loaded on old kernel that does not have definition
for 'does_not_exist' struct_ops member. After this commit it would be
possible to load such object file after the following tweaks:
bpf_program__set_autoload(skel->progs.bar, false);
bpf_map__set_autocreate(skel->maps.map_for_new, false);
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20240306104529.6453-4-eddyz87@gmail.com
|
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Eduard Zingerman
|
d9ab2f76ef |
libbpf: Tie struct_ops programs to kernel BTF ids, not to local ids
Enforce the following existing limitation on struct_ops programs based
on kernel BTF id instead of program-local BTF id:
struct_ops BPF prog can be re-used between multiple .struct_ops &
.struct_ops.link as long as it's the same struct_ops struct
definition and the same function pointer field
This allows reusing same BPF program for versioned struct_ops map
definitions, e.g.:
SEC("struct_ops/test")
int BPF_PROG(foo) { ... }
struct some_ops___v1 { int (*test)(void); };
struct some_ops___v2 { int (*test)(void); };
SEC(".struct_ops.link") struct some_ops___v1 a = { .test = foo }
SEC(".struct_ops.link") struct some_ops___v2 b = { .test = foo }
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-3-eddyz87@gmail.com
|
||
|
Eduard Zingerman
|
a2a5172cf1 |
libbpf: Allow version suffixes (___smth) for struct_ops types
E.g. allow the following struct_ops definitions:
struct bpf_testmod_ops___v1 { int (*test)(void); };
struct bpf_testmod_ops___v2 { int (*test)(void); };
SEC(".struct_ops.link")
struct bpf_testmod_ops___v1 a = { .test = ... }
SEC(".struct_ops.link")
struct bpf_testmod_ops___v2 b = { .test = ... }
Where both bpf_testmod_ops__v1 and bpf_testmod_ops__v2 would be
resolved as 'struct bpf_testmod_ops' from kernel BTF.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-2-eddyz87@gmail.com
|
||
Chen Shen
|
25703adf45 |
libbpf: Correct debug message in btf__load_vmlinux_btf
In the function btf__load_vmlinux_btf, the debug message incorrectly refers to 'path' instead of 'sysfs_btf_path'. Signed-off-by: Chen Shen <peterchenshen@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20240302062218.3587-1-peterchenshen@gmail.com |
||
|
Kui-Feng Lee
|
69e4a9d2b3 |
libbpf: Convert st_ops->data to shadow type.
Convert st_ops->data to the shadow type of the struct_ops map. The shadow type of a struct_ops type is a variant of the original struct type providing a way to access/change the values in the maps of the struct_ops type. bpf_map__initial_value() will return st_ops->data for struct_ops types. The skeleton is going to use it as the pointer to the shadow type of the original struct type. One of the main differences between the original struct type and the shadow type is that all function pointers of the shadow type are converted to pointers of struct bpf_program. Users can replace these bpf_program pointers with other BPF programs. The st_ops->progs[] will be updated before updating the value of a map to reflect the changes made by users. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240229064523.2091270-3-thinker.li@gmail.com |
||
|
Kui-Feng Lee
|
3644d28546 |
libbpf: Set btf_value_type_id of struct bpf_map for struct_ops.
For a struct_ops map, btf_value_type_id is the type ID of it's struct type. This value is required by bpftool to generate skeleton including pointers of shadow types. The code generator gets the type ID from bpf_map__btf_value_type_id() in order to get the type information of the struct type of a map. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240229064523.2091270-2-thinker.li@gmail.com |
||
Ian Rogers
|
1947b92464 |
libperf evlist: Avoid out-of-bounds access
Parallel testing appears to show a race between allocating and setting
evsel ids. As there is a bounds check on the xyarray it yields a segv
like:
```
AddressSanitizer:DEADLYSIGNAL
=================================================================
==484408==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000010
==484408==The signal is caused by a WRITE memory access.
==484408==Hint: address points to the zero page.
#0 0x55cef5d4eff4 in perf_evlist__id_hash tools/lib/perf/evlist.c:256
#1 0x55cef5d4f132 in perf_evlist__id_add tools/lib/perf/evlist.c:274
#2 0x55cef5d4f545 in perf_evlist__id_add_fd tools/lib/perf/evlist.c:315
#3 0x55cef5a1923f in store_evsel_ids util/evsel.c:3130
#4 0x55cef5a19400 in evsel__store_ids util/evsel.c:3147
#5 0x55cef5888204 in __run_perf_stat tools/perf/builtin-stat.c:832
#6 0x55cef5888c06 in run_perf_stat tools/perf/builtin-stat.c:960
#7 0x55cef58932db in cmd_stat tools/perf/builtin-stat.c:2878
...
```
Avoid this crash by early exiting the perf_evlist__id_add_fd and
perf_evlist__id_add is the access is out-of-bounds.
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240229070757.796244-1-irogers@google.com
|
||
Martin Kelly
|
58fd62e0aa |
bpf: Clarify batch lookup/lookup_and_delete semantics
The batch lookup and lookup_and_delete APIs have two parameters, in_batch and out_batch, to facilitate iterative lookup/lookup_and_deletion operations for supported maps. Except NULL for in_batch at the start of these two batch operations, both parameters need to point to memory equal or larger than the respective map key size, except for various hashmaps (hash, percpu_hash, lru_hash, lru_percpu_hash) where the in_batch/out_batch memory size should be at least 4 bytes. Document these semantics to clarify the API. Signed-off-by: Martin Kelly <martin.kelly@crowdstrike.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240221211838.1241578-1-martin.kelly@crowdstrike.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
|
Ian Rogers
|
1a562c0d44 |
tools subcmd: Add a no exec function call option
Tools like perf fork tests in case they crash, but they don't want to exec a full binary. Add an option to call a function rather than do an exec. The child process exits with the result of the function call and is passed the struct of the run_command, things like container_of can then allow the child process function to determine additional arguments. Signed-off-by: Ian Rogers <irogers@google.com> Cc: James Clark <james.clark@arm.com> Cc: Justin Stitt <justinstitt@google.com> Cc: Bill Wendling <morbo@google.com> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: llvm@lists.linux.dev Signed-off-by: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20240221034155.1500118-5-irogers@google.com |
||
Matt Bobrowski
|
1159d27852 |
libbpf: Make remark about zero-initializing bpf_*_info structs
In some situations, if you fail to zero-initialize the
bpf_{prog,map,btf,link}_info structs supplied to the set of LIBBPF
helpers bpf_{prog,map,btf,link}_get_info_by_fd(), you can expect the
helper to return an error. This can possibly leave people in a
situation where they're scratching their heads for an unnnecessary
amount of time. Make an explicit remark about the requirement of
zero-initializing the supplied bpf_{prog,map,btf,link}_info structs
for the respective LIBBPF helpers.
Internally, LIBBPF helpers bpf_{prog,map,btf,link}_get_info_by_fd()
call into bpf_obj_get_info_by_fd() where the bpf(2)
BPF_OBJ_GET_INFO_BY_FD command is used. This specific command is
effectively backed by restrictions enforced by the
bpf_check_uarg_tail_zero() helper. This function ensures that if the
size of the supplied bpf_{prog,map,btf,link}_info structs are larger
than what the kernel can handle, trailing bits are zeroed. This can be
a problem when compiling against UAPI headers that don't necessarily
match the sizes of the same underlying types known to the kernel.
Signed-off-by: Matt Bobrowski <mattbobrowski@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/bpf/ZcyEb8x4VbhieWsL@google.com
|
||
Cupertino Miranda
|
12bbcf8e84 |
libbpf: Add support to GCC in CORE macro definitions
Due to internal differences between LLVM and GCC the current implementation for the CO-RE macros does not fit GCC parser, as it will optimize those expressions even before those would be accessible by the BPF backend. As examples, the following would be optimized out with the original definitions: - As enums are converted to their integer representation during parsing, the IR would not know how to distinguish an integer constant from an actual enum value. - Types need to be kept as temporary variables, as the existing type casts of the 0 address (as expanded for LLVM), are optimized away by the GCC C parser, never really reaching GCCs IR. Although, the macros appear to add extra complexity, the expanded code is removed from the compilation flow very early in the compilation process, not really affecting the quality of the generated assembly. Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240213173543.1397708-1-cupertino.miranda@oracle.com |
||
Toke Høiland-Jørgensen
|
92a871ab9f |
libbpf: Use OPTS_SET() macro in bpf_xdp_query()
When the feature_flags and xdp_zc_max_segs fields were added to the libbpf
bpf_xdp_query_opts, the code writing them did not use the OPTS_SET() macro.
This causes libbpf to write to those fields unconditionally, which means
that programs compiled against an older version of libbpf (with a smaller
size of the bpf_xdp_query_opts struct) will have its stack corrupted by
libbpf writing out of bounds.
The patch adding the feature_flags field has an early bail out if the
feature_flags field is not part of the opts struct (via the OPTS_HAS)
macro, but the patch adding xdp_zc_max_segs does not. For consistency, this
fix just changes the assignments to both fields to use the OPTS_SET()
macro.
Fixes:
|
||
|
Andrii Nakryiko
|
d7bc416aa5 |
libbpf: fix return value for PERF_EVENT __arg_ctx type fix up check
If PERF_EVENT program has __arg_ctx argument with matching
architecture-specific pt_regs/user_pt_regs/user_regs_struct pointer
type, libbpf should still perform type rewrite for old kernels, but not
emit the warning. Fix copy/paste from kernel code where 0 is meant to
signify "no error" condition. For libbpf we need to return "true" to
proceed with type rewrite (which for PERF_EVENT program will be
a canonical `struct bpf_perf_event_data *` type).
Fixes:
|
||
|
Andrii Nakryiko
|
b9551da8cf |
libbpf: Add missed btf_ext__raw_data() API
Another API that was declared in libbpf.map but actual implementation
was missing. btf_ext__get_raw_data() was intended as a discouraged alias
to consistently-named btf_ext__raw_data(), so make this an actuality.
Fixes:
|
||
|
Andrii Nakryiko
|
c81a8ab196 |
libbpf: Add btf__new_split() API that was declared but not implemented
Seems like original commit adding split BTF support intended to add
btf__new_split() API, and even declared it in libbpf.map, but never
added (trivial) implementation. Fix this.
Fixes:
|
||
|
Andrii Nakryiko
|
93ee1eb85e |
libbpf: Add missing LIBBPF_API annotation to libbpf_set_memlock_rlim API
LIBBPF_API annotation seems missing on libbpf_set_memlock_rlim API, so add it to make this API callable from libbpf's shared library version. Fixes: |
||
|
Andrii Nakryiko
|
9fa5e1a180 |
libbpf: Call memfd_create() syscall directly
Some versions of Android do not implement memfd_create() wrapper in their libc implementation, leading to build failures ([0]). On the other hand, memfd_create() is available as a syscall on quite old kernels (3.17+, while bpf() syscall itself is available since 3.18+), so it is ok to assume that syscall availability and call into it with syscall() helper to avoid Android-specific workarounds. Validated in libbpf-bootstrap's CI ([1]). [0] https://github.com/libbpf/libbpf-bootstrap/actions/runs/7701003207/job/20986080319#step:5:83 [1] https://github.com/libbpf/libbpf-bootstrap/actions/runs/7715988887/job/21031767212?pr=253 Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240201172027.604869-2-andrii@kernel.org |
||
|
Eduard Zingerman
|
8263b3382d |
libbpf: Remove unnecessary null check in kernel_supports()
After recent changes, Coverity complained about inconsistent null checks
in kernel_supports() function:
kernel_supports(const struct bpf_object *obj, ...)
[...]
// var_compare_op: Comparing obj to null implies that obj might be null
if (obj && obj->gen_loader)
return true;
// var_deref_op: Dereferencing null pointer obj
if (obj->token_fd)
return feat_supported(obj->feat_cache, feat_id);
[...]
- The original null check was introduced by commit [0], which introduced
a call `kernel_supports(NULL, ...)` in function bump_rlimit_memlock();
- This call was refactored to use `feat_supported(NULL, ...)` in commit [1].
Looking at all places where kernel_supports() is called:
- There is either `obj->...` access before the call;
- Or `obj` comes from `prog->obj` expression, where `prog` comes from
enumeration of programs in `obj`;
- Or `obj` comes from `prog->obj`, where `prog` is a parameter to one
of the API functions:
- bpf_program__attach_kprobe_opts;
- bpf_program__attach_kprobe;
- bpf_program__attach_ksyscall.
Assuming correct API usage, it appears that `obj` can never be null when
passed to kernel_supports(). Silence the Coverity warning by removing
redundant null check.
[0]
|
||
|
Andrii Nakryiko
|
20d59ee551 |
libbpf: add bpf_core_cast() macro
Add bpf_core_cast() macro that wraps bpf_rdonly_cast() kfunc. It's more ergonomic than kfunc, as it automatically extracts btf_id with bpf_core_type_id_kernel(), and works with type names. It also casts result to (T *) pointer. See the definition of the macro, it's self-explanatory. libbpf declares bpf_rdonly_cast() extern as __weak __ksym and should be safe to not conflict with other possible declarations in user code. But we do have a conflict with current BPF selftests that declare their externs with first argument as `void *obj`, while libbpf opts into more permissive `const void *obj`. This causes conflict, so we fix up BPF selftests uses in the same patch. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240130212023.183765-2-andrii@kernel.org Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
|
Andrii Nakryiko
|
d28bb1a86e |
libbpf: add __arg_trusted and __arg_nullable tag macros
Add __arg_trusted to annotate global func args that accept trusted PTR_TO_BTF_ID arguments. Also add __arg_nullable to combine with __arg_trusted (and maybe other tags in the future) to force global subprog itself (i.e., callee) to do NULL checks, as opposed to default non-NULL semantics (and thus caller's responsibility to ensure non-NULL values). Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240130000648.2144827-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Ian Rogers
|
f2e4040c82 |
libbpf: Add some details for BTF parsing failures
As CONFIG_DEBUG_INFO_BTF is default off the existing "failed to find valid kernel BTF" message makes diagnosing the kernel build issue somewhat cryptic. Add a little more detail with the hope of helping users. Before: ``` libbpf: failed to find valid kernel BTF libbpf: Error loading vmlinux BTF: -3 ``` After not accessible: ``` libbpf: kernel BTF is missing at '/sys/kernel/btf/vmlinux', was CONFIG_DEBUG_INFO_BTF enabled? libbpf: failed to find valid kernel BTF libbpf: Error loading vmlinux BTF: -3 ``` After not readable: ``` libbpf: failed to read kernel BTF from (/sys/kernel/btf/vmlinux): -1 ``` Closes: https://lore.kernel.org/bpf/CAP-5=fU+DN_+Y=Y4gtELUsJxKNDDCOvJzPHvjUVaUoeFAzNnig@mail.gmail.com/ Signed-off-by: Ian Rogers <irogers@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240125231840.1647951-1-irogers@google.com |
||
|
Andrii Nakryiko
|
9eea8fafe3 |
libbpf: fix __arg_ctx type enforcement for perf_event programs
Adjust PERF_EVENT type enforcement around __arg_ctx to match exactly
what kernel is doing.
Fixes:
|
||
|
Andrii Nakryiko
|
0e6d0a9d23 |
libbpf: integrate __arg_ctx feature detector into kernel_supports()
Now that feature detection code is in bpf-next tree, integrate __arg_ctx kernel-side support into kernel_supports() framework. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240125205510.3642094-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
ad57654053 |
libbpf: Fix faccessat() usage on Android
Android implementation of libc errors out with -EINVAL in faccessat() if
passed AT_EACCESS ([0]), this leads to ridiculous issue with libbpf
refusing to load /sys/kernel/btf/vmlinux on Androids ([1]). Fix by
detecting Android and redefining AT_EACCESS to 0, it's equivalent on
Android.
[0] https://android.googlesource.com/platform/bionic/+/refs/heads/android13-release/libc/bionic/faccessat.cpp#50
[1] https://github.com/libbpf/libbpf-bootstrap/issues/250#issuecomment-1911324250
Fixes:
|
||
Jakub Kicinski
|
92046e83c0 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZbQV+gAKCRDbK58LschI g2OeAP0VvhZS9SPiS+/AMAFuw2W1BkMrFNbfBTc3nzRnyJSmNAD+NG4CLLJvsKI9 olu7VC20B8pLTGLUGIUSwqnjOC+Kkgc= =wVMl -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-01-26 We've added 107 non-merge commits during the last 4 day(s) which contain a total of 101 files changed, 6009 insertions(+), 1260 deletions(-). The main changes are: 1) Add BPF token support to delegate a subset of BPF subsystem functionality from privileged system-wide daemons such as systemd through special mount options for userns-bound BPF fs to a trusted & unprivileged application. With addressed changes from Christian and Linus' reviews, from Andrii Nakryiko. 2) Support registration of struct_ops types from modules which helps projects like fuse-bpf that seeks to implement a new struct_ops type, from Kui-Feng Lee. 3) Add support for retrieval of cookies for perf/kprobe multi links, from Jiri Olsa. 4) Bigger batch of prep-work for the BPF verifier to eventually support preserving boundaries and tracking scalars on narrowing fills, from Maxim Mikityanskiy. 5) Extend the tc BPF flavor to support arbitrary TCP SYN cookies to help with the scenario of SYN floods, from Kuniyuki Iwashima. 6) Add code generation to inline the bpf_kptr_xchg() helper which improves performance when stashing/popping the allocated BPF objects, from Hou Tao. 7) Extend BPF verifier to track aligned ST stores as imprecise spilled registers, from Yonghong Song. 8) Several fixes to BPF selftests around inline asm constraints and unsupported VLA code generation, from Jose E. Marchesi. 9) Various updates to the BPF IETF instruction set draft document such as the introduction of conformance groups for instructions, from Dave Thaler. 10) Fix BPF verifier to make infinite loop detection in is_state_visited() exact to catch some too lax spill/fill corner cases, from Eduard Zingerman. 11) Refactor the BPF verifier pointer ALU check to allow ALU explicitly instead of implicitly for various register types, from Hao Sun. 12) Fix the flaky tc_redirect_dtime BPF selftest due to slowness in neighbor advertisement at setup time, from Martin KaFai Lau. 13) Change BPF selftests to skip callback tests for the case when the JIT is disabled, from Tiezhu Yang. 14) Add a small extension to libbpf which allows to auto create a map-in-map's inner map, from Andrey Grafin. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (107 commits) selftests/bpf: Add missing line break in test_verifier bpf, docs: Clarify definitions of various instructions bpf: Fix error checks against bpf_get_btf_vmlinux(). bpf: One more maintainer for libbpf and BPF selftests selftests/bpf: Incorporate LSM policy to token-based tests selftests/bpf: Add tests for LIBBPF_BPF_TOKEN_PATH envvar libbpf: Support BPF token path setting through LIBBPF_BPF_TOKEN_PATH envvar selftests/bpf: Add tests for BPF object load with implicit token selftests/bpf: Add BPF object loading tests with explicit token passing libbpf: Wire up BPF token support at BPF object level libbpf: Wire up token_fd into feature probing logic libbpf: Move feature detection code into its own file libbpf: Further decouple feature checking logic from bpf_object libbpf: Split feature detectors definitions from cached results selftests/bpf: Utilize string values for delegate_xxx mount options bpf: Support symbolic BPF FS delegation mount options bpf: Fail BPF_TOKEN_CREATE if no delegation option was set on BPF FS bpf,selinux: Allocate bpf_security_struct per BPF token selftests/bpf: Add BPF token-enabled tests libbpf: Add BPF token support to bpf_prog_load() API ... ==================== Link: https://lore.kernel.org/r/20240126215710.19855-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
||
|
Andrii Nakryiko
|
cac270ad79 |
libbpf: Support BPF token path setting through LIBBPF_BPF_TOKEN_PATH envvar
To allow external admin authority to override default BPF FS location (/sys/fs/bpf) for implicit BPF token creation, teach libbpf to recognize LIBBPF_BPF_TOKEN_PATH envvar. If it is specified and user application didn't explicitly specify bpf_token_path option, it will be treated exactly like bpf_token_path option, overriding default /sys/fs/bpf location and making BPF token mandatory. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-29-andrii@kernel.org |
||
|
Andrii Nakryiko
|
6b434b61b4 |
libbpf: Wire up BPF token support at BPF object level
Add BPF token support to BPF object-level functionality.
BPF token is supported by BPF object logic either as an explicitly
provided BPF token from outside (through BPF FS path), or implicitly
(unless prevented through bpf_object_open_opts).
Implicit mode is assumed to be the most common one for user namespaced
unprivileged workloads. The assumption is that privileged container
manager sets up default BPF FS mount point at /sys/fs/bpf with BPF token
delegation options (delegate_{cmds,maps,progs,attachs} mount options).
BPF object during loading will attempt to create BPF token from
/sys/fs/bpf location, and pass it for all relevant operations
(currently, map creation, BTF load, and program load).
In this implicit mode, if BPF token creation fails due to whatever
reason (BPF FS is not mounted, or kernel doesn't support BPF token,
etc), this is not considered an error. BPF object loading sequence will
proceed with no BPF token.
In explicit BPF token mode, user provides explicitly custom BPF FS mount
point path. In such case, BPF object will attempt to create BPF token
from provided BPF FS location. If BPF token creation fails, that is
considered a critical error and BPF object load fails with an error.
Libbpf provides a way to disable implicit BPF token creation, if it
causes any troubles (BPF token is designed to be completely optional and
shouldn't cause any problems even if provided, but in the world of BPF
LSM, custom security logic can be installed that might change outcome
depending on the presence of BPF token). To disable libbpf's default BPF
token creation behavior user should provide either invalid BPF token FD
(negative), or empty bpf_token_path option.
BPF token presence can influence libbpf's feature probing, so if BPF
object has associated BPF token, feature probing is instructed to use
BPF object-specific feature detection cache and token FD.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-26-andrii@kernel.org
|
||
|
Andrii Nakryiko
|
f3dcee938f |
libbpf: Wire up token_fd into feature probing logic
Adjust feature probing callbacks to take into account optional token_fd. In unprivileged contexts, some feature detectors would fail to detect kernel support just because BPF program, BPF map, or BTF object can't be loaded due to privileged nature of those operations. So when BPF object is loaded with BPF token, this token should be used for feature probing. This patch is setting support for this scenario, but we don't yet pass non-zero token FD. This will be added in the next patch. We also switched BPF cookie detector from using kprobe program to tracepoint one, as tracepoint is somewhat less dangerous BPF program type and has higher likelihood of being allowed through BPF token in the future. This change has no effect on detection behavior. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-25-andrii@kernel.org |
||
|
Andrii Nakryiko
|
05f9cdd55d |
libbpf: Move feature detection code into its own file
It's quite a lot of well isolated code, so it seems like a good candidate to move it out of libbpf.c to reduce its size. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-24-andrii@kernel.org |
||
|
Andrii Nakryiko
|
d6dd1d4936 |
libbpf: Further decouple feature checking logic from bpf_object
Add feat_supported() helper that accepts feature cache instead of bpf_object. This allows low-level code in bpf.c to not know or care about higher-level concept of bpf_object, yet it will be able to utilize custom feature checking in cases where BPF token might influence the outcome. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-23-andrii@kernel.org |
||
|
Andrii Nakryiko
|
ea4d587354 |
libbpf: Split feature detectors definitions from cached results
Split a list of supported feature detectors with their corresponding callbacks from actual cached supported/missing values. This will allow to have more flexible per-token or per-object feature detectors in subsequent refactorings. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-22-andrii@kernel.org |
||
|
Andrii Nakryiko
|
404cbc149c |
libbpf: Add BPF token support to bpf_prog_load() API
Wire through token_fd into bpf_prog_load(). Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-16-andrii@kernel.org |
||
|
Andrii Nakryiko
|
a3d63e8525 |
libbpf: Add BPF token support to bpf_btf_load() API
Allow user to specify token_fd for bpf_btf_load() API that wraps kernel's BPF_BTF_LOAD command. This allows loading BTF from unprivileged process as long as it has BPF token allowing BPF_BTF_LOAD command, which can be created and delegated by privileged process. Wire through new btf_flags as well, so that user can provide BPF_F_TOKEN_FD flag, if necessary. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-15-andrii@kernel.org |
||
|
Andrii Nakryiko
|
364f848375 |
libbpf: Add BPF token support to bpf_map_create() API
Add ability to provide token_fd for BPF_MAP_CREATE command through bpf_map_create() API. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-14-andrii@kernel.org |
||
|
Andrii Nakryiko
|
639ecd7d62 |
libbpf: Add bpf_token_create() API
Add low-level wrapper API for BPF_TOKEN_CREATE command in bpf() syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-13-andrii@kernel.org |
||
Martin KaFai Lau
|
c9f1155645 |
libbpf: Ensure undefined bpf_attr field stays 0
The commit |
||
Dima Tisnek
|
d47b9f68d2 |
libbpf: Correct bpf_core_read.h comment wrt bpf_core_relo struct
Past commit ([0]) removed the last vestiges of struct bpf_field_reloc,
it's called struct bpf_core_relo now.
[0]
|
||
|
Kui-Feng Lee
|
9e926acda0 |
libbpf: Find correct module BTFs for struct_ops maps and progs.
Locate the module BTFs for struct_ops maps and progs and pass them to the kernel. This ensures that the kernel correctly resolves type IDs from the appropriate module BTFs. For the map of a struct_ops object, the FD of the module BTF is set to bpf_map to keep a reference to the module BTF. The FD is passed to the kernel as value_type_btf_obj_fd when the struct_ops object is loaded. For a bpf_struct_ops prog, attach_btf_obj_fd of bpf_prog is the FD of a module BTF in the kernel. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240119225005.668602-13-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
||
|
Andrii Nakryiko
|
bc308d011a |
libbpf: call dup2() syscall directly
We've ran into issues with using dup2() API in production setting, where libbpf is linked into large production environment and ends up calling unintended custom implementations of dup2(). These custom implementations don't provide atomic FD replacement guarantees of dup2() syscall, leading to subtle and hard to debug issues. To prevent this in the future and guarantee that no libc implementation will do their own custom non-atomic dup2() implementation, call dup2() syscall directly with syscall(SYS_dup2). Note that some architectures don't seem to provide dup2 and have dup3 instead. Try to detect and pick best syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240119210201.1295511-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Andrey Grafin
|
f04deb90e5 |
libbpf: Apply map_set_def_max_entries() for inner_maps on creation
This patch allows to auto create BPF_MAP_TYPE_ARRAY_OF_MAPS and
BPF_MAP_TYPE_HASH_OF_MAPS with values of BPF_MAP_TYPE_PERF_EVENT_ARRAY
by bpf_object__load().
Previous behaviour created a zero filled btf_map_def for inner maps and
tried to use it for a map creation but the linux kernel forbids to create
a BPF_MAP_TYPE_PERF_EVENT_ARRAY map with max_entries=0.
Fixes:
|
||
|
Linus Torvalds
|
9d64bf433c |
perf tools improvements and fixes for v6.8:
- Add Namhyung Kim as tools/perf/ co-maintainer, we're taking turns processing
patches, switching roles from perf-tools to perf-tools-next at each Linux
release.
Data profiling:
- Associate samples that identify loads and stores with data structures. This
uses events available on Intel, AMD and others and DWARF info:
# To get memory access samples in kernel for 1 second (on Intel)
$ perf mem record -a -K --ldlat=4 -- sleep 1
# Similar for the AMD (but it requires 6.3+ kernel for BPF filters)
$ perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000' -- sleep 1
Then, amongst several modes of post processing, one can do things like:
$ perf report -s type,typeoff --hierarchy --group --stdio
...
#
# Samples: 10K of events 'cpu/mem-loads,ldlat=4/P, cpu/mem-stores/P, dummy:u'
# Event count (approx.): 602758064
#
# Overhead Data Type / Data Type Offset
# ........................... ............................
#
26.09% 3.28% 0.00% long unsigned int
26.09% 3.28% 0.00% long unsigned int +0 (no field)
18.48% 0.73% 0.00% struct page
10.83% 0.02% 0.00% struct page +8 (lru.next)
3.90% 0.28% 0.00% struct page +0 (flags)
3.45% 0.06% 0.00% struct page +24 (mapping)
0.25% 0.28% 0.00% struct page +48 (_mapcount.counter)
0.02% 0.06% 0.00% struct page +32 (index)
0.02% 0.00% 0.00% struct page +52 (_refcount.counter)
0.02% 0.01% 0.00% struct page +56 (memcg_data)
0.00% 0.01% 0.00% struct page +16 (lru.prev)
15.37% 17.54% 0.00% (stack operation)
15.37% 17.54% 0.00% (stack operation) +0 (no field)
11.71% 50.27% 0.00% (unknown)
11.71% 50.27% 0.00% (unknown) +0 (no field)
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
$ perf annotate --data-type=page --group
Annotate type: 'struct page' in [kernel.kallsyms] (480 samples):
event[0] = cpu/mem-loads,ldlat=4/P
event[1] = cpu/mem-stores/P
event[2] = dummy:u
===================================================================================
samples offset size field
447 33 0 0 64 struct page {
108 8 0 0 8 long unsigned int flags;
319 13 0 8 40 union {
319 13 0 8 40 struct {
236 2 0 8 16 union {
236 2 0 8 16 struct list_head lru {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct {
236 1 0 8 8 void* __filler;
0 1 0 16 4 unsigned int mlock_count;
};
236 2 0 8 16 struct list_head buddy_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct list_head pcp_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
};
82 4 0 24 8 struct address_space* mapping;
1 7 0 32 8 union {
1 7 0 32 8 long unsigned int index;
1 7 0 32 8 long unsigned int share;
};
0 0 0 40 8 long unsigned int private;
};
This uses the existing annotate code, calling objdump to do the disassembly,
with improvements to avoid having this take too long, but longer term a
switch to a disassembler library, possibly reusing code in the kernel will
be pursued.
This is the initial implementation, please use it and report impressions and
bugs. Make sure the kernel-debuginfo packages match the running kernel. The
'perf report' phase for non short perf.data files may take a while.
There is a great article about it on LWN:
https://lwn.net/Articles/955709/ - "Data-type profiling for perf"
One last test I did while writing this text, on a AMD Ryzen 5950X, using a distro
kernel, while doing a simple 'find /' on an otherwise idle system resulted in:
# uname -r
6.6.9-100.fc38.x86_64
# perf -vv | grep BPF_
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
bpf_skeletons: [ on ] # HAVE_BPF_SKEL
# rpm -qa | grep kernel-debuginfo
kernel-debuginfo-common-x86_64-6.6.9-100.fc38.x86_64
kernel-debuginfo-6.6.9-100.fc38.x86_64
#
# perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000'
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 2.199 MB perf.data (2913 samples) ]
#
# ls -la perf.data
-rw-------. 1 root root 2346486 Jan 9 18:36 perf.data
# perf evlist
ibs_op//
dummy:u
# perf evlist -v
ibs_op//: type: 11, size: 136, config: 0, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1
dummy:u: type: 1 (PERF_TYPE_SOFTWARE), size: 136, config: 0x9 (PERF_COUNT_SW_DUMMY), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|ADDR|CPU|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, task: 1, mmap_data: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
#
# perf report -s type,typeoff --hierarchy --group --stdio
# Total Lost Samples: 0
#
# Samples: 2K of events 'ibs_op//, dummy:u'
# Event count (approx.): 1904553038
#
# Overhead Data Type / Data Type Offset
# ................... ............................
#
73.70% 0.00% (unknown)
73.70% 0.00% (unknown) +0 (no field)
3.01% 0.00% long unsigned int
3.00% 0.00% long unsigned int +0 (no field)
0.01% 0.00% long unsigned int +2 (no field)
2.73% 0.00% struct task_struct
1.71% 0.00% struct task_struct +52 (on_cpu)
0.38% 0.00% struct task_struct +2104 (rcu_read_unlock_special.b.blocked)
0.23% 0.00% struct task_struct +2100 (rcu_read_lock_nesting)
0.14% 0.00% struct task_struct +2384 ()
0.06% 0.00% struct task_struct +3096 (signal)
0.05% 0.00% struct task_struct +3616 (cgroups)
0.05% 0.00% struct task_struct +2344 (active_mm)
0.02% 0.00% struct task_struct +46 (flags)
0.02% 0.00% struct task_struct +2096 (migration_disabled)
0.01% 0.00% struct task_struct +24 (__state)
0.01% 0.00% struct task_struct +3956 (mm_cid_active)
0.01% 0.00% struct task_struct +1048 (cpus_ptr)
0.01% 0.00% struct task_struct +184 (se.group_node.next)
0.01% 0.00% struct task_struct +20 (thread_info.cpu)
0.00% 0.00% struct task_struct +104 (on_rq)
0.00% 0.00% struct task_struct +2456 (pid)
1.36% 0.00% struct module
0.59% 0.00% struct module +952 (kallsyms)
0.42% 0.00% struct module +0 (state)
0.23% 0.00% struct module +8 (list.next)
0.12% 0.00% struct module +216 (syms)
0.95% 0.00% struct inode
0.41% 0.00% struct inode +40 (i_sb)
0.22% 0.00% struct inode +0 (i_mode)
0.06% 0.00% struct inode +76 (i_rdev)
0.06% 0.00% struct inode +56 (i_security)
<SNIP>
perf top/report:
- Don't ignore job control, allowing control+Z + bg to work.
- Add s390 raw data interpretation for PAI (Processor Activity Instrumentation)
counters.
perf archive:
- Add new option '--all' to pack perf.data with DSOs.
- Add new option '--unpack' to expand tarballs.
Initialization speedups:
- Lazily initialize zstd streams to save memory when not using it.
- Lazily allocate/size mmap event copy.
- Lazy load kernel symbols in 'perf record'.
- Be lazier in allocating lost samples buffer in 'perf record'.
- Don't synthesize BPF events when disabled via the command line (perf record --no-bpf-event).
Assorted improvements:
- Show note on AMD systems that the :p, :pp, :ppp and :P are all the same, as
IBS (Instruction Based Sampling) is used and it is inherentely precise, not
having levels of precision like in Intel systems.
- When 'cycles' isn't available, fall back to the "task-clock" event when not
system wide, not to 'cpu-clock'.
- Add --debug-file option to redirect debug output, e.g.:
$ perf --debug-file /tmp/perf.log record -v true
- Shrink 'struct map' to under one cacheline by avoiding function pointers for
selecting if addresses are identity or DSO relative, and using just a byte for
some boolean struct members.
- Resolve the arch specific strerrno just once to use in perf_env__arch_strerrno().
- Reduce memory for recording PERF_RECORD_LOST_SAMPLES event.
Assorted fixes:
- Fix the default 'perf top' usage on Intel hybrid systems, now it starts with
a browser showing the number of samples for Efficiency (cpu_atom/cycles/P) and
Performance (cpu_core/cycles/P). This behaviour is similar on ARM64, with its
respective set of big.LITTLE processors.
- Fix segfault on build_mem_topology() error path.
- Fix 'perf mem' error on hybrid related to availability of mem event in a PMU.
- Fix missing reference count gets (map, maps) in the db-export code.
- Avoid recursively taking env->bpf_progs.lock in the 'perf_env' code.
- Use the newly introduced maps__for_each_map() to add missing locking around
iteration of 'struct map' entries.
- Parse NOTE segments until the build id is found, don't stop on the first one,
ELF files may have several such NOTE segments.
- Remove 'egrep' usage, its deprecated, use 'grep -E' instead.
- Warn first about missing libelf, not libbpf, that depends on libelf.
- Use alternative to 'find ... -printf' as this isn't supported in busybox.
- Address python 3.6 DeprecationWarning for string scapes.
- Fix memory leak in uniq() in libsubcmd.
- Fix man page formatting for 'perf lock'
- Fix some spelling mistakes.
perf tests:
- Fail shell tests that needs some symbol in perf itself if it is stripped.
These tests check if a symbol is resolved, if some hot function is indeed
detected by profiling, etc.
- The 'perf test sigtrap' test is currently failing on PREEMPT_RT, skip it if
sleeping spinlocks are detected (using BTF) and point to the mailing list
discussion about it. This test is also being skipped on several architectures
(powerpc, s390x, arm and aarch64) due to other pending issues with intruction
breakpoints.
- Adjust test case perf record offcpu profiling tests for s390.
- Fix 'Setup struct perf_event_attr' fails on s390 on z/VM guest, addressing
issues caused by the fallback from cycles to task-clock done in this release.
- Fix mask for VG register in the user-regs test.
- Use shellcheck on 'perf test' shell scripts automatically to make sure changes
don't introduce things it flags as problematic.
- Add option to change objdump binary and allow it to be set via 'perf config'.
- Add basic 'perf script', 'perf list --json" and 'perf diff' tests.
- Basic branch counter support.
- Make DSO tests a suite rather than individual.
- Remove atomics from test_loop to avoid test failures.
- Fix call chain match on powerpc for the record+probe_libc_inet_pton test.
- Improve Intel hybrid tests.
Vendor event files (JSON):
powerpc:
- Update datasource event name to fix duplicate events on IBM's Power10.
- Add PVN for HX-C2000 CPU with Power8 Architecture.
Intel:
- Alderlake/rocketlake metric fixes.
- Update emeraldrapids events to v1.02.
- Update icelakex events to v1.23.
- Update sapphirerapids events to v1.17.
- Add skx, clx, icx and spr upi bandwidth metric.
AMD:
- Add Zen 4 memory controller events.
RISC-V:
- Add StarFive Dubhe-80 and Dubhe-90 JSON files.
https://www.starfivetech.com/en/site/cpu-u
- Add T-HEAD C9xx JSON file.
https://github.com/riscv-software-src/opensbi/blob/master/docs/platform/thead-c9xx.md
ARM64:
- Remove UTF-8 characters from cmn.json, that were causing build failure in some
distros.
- Add core PMU events and metrics for Ampere One X.
- Rename Ampere One's BPU_FLUSH_MEM_FAULT to GPC_FLUSH_MEM_FAULT
libperf:
- Rename several perf_cpu_map constructor names to clarify what they really do.
- Ditto for some other methods, coping with some issues in their semantics,
like perf_cpu_map__empty() -> perf_cpu_map__has_any_cpu_or_is_empty().
- Document perf_cpu_map__nr()'s behavior
perf stat:
- Exit if parse groups fails.
- Combine the -A/--no-aggr and --no-merge options.
- Fix help message for --metric-no-threshold option.
Hardware tracing:
ARM64 CoreSight:
- Bump minimum OpenCSD version to ensure a bugfix is present.
- Add 'T' itrace option for timestamp trace
- Set start vm addr of exectable file to 0 and don't ignore first sample on the
arm-cs-trace-disasm.py 'perf script'.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-tools-for-v6.8-1-2024-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Arnaldo Carvalho de Melo:
"Add Namhyung Kim as tools/perf/ co-maintainer, we're taking turns
processing patches, switching roles from perf-tools to perf-tools-next
at each Linux release.
Data profiling:
- Associate samples that identify loads and stores with data
structures. This uses events available on Intel, AMD and others and
DWARF info:
# To get memory access samples in kernel for 1 second (on Intel)
$ perf mem record -a -K --ldlat=4 -- sleep 1
# Similar for the AMD (but it requires 6.3+ kernel for BPF filters)
$ perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000' -- sleep 1
Then, amongst several modes of post processing, one can do things like:
$ perf report -s type,typeoff --hierarchy --group --stdio
...
#
# Samples: 10K of events 'cpu/mem-loads,ldlat=4/P, cpu/mem-stores/P, dummy:u'
# Event count (approx.): 602758064
#
# Overhead Data Type / Data Type Offset
# ........................... ............................
#
26.09% 3.28% 0.00% long unsigned int
26.09% 3.28% 0.00% long unsigned int +0 (no field)
18.48% 0.73% 0.00% struct page
10.83% 0.02% 0.00% struct page +8 (lru.next)
3.90% 0.28% 0.00% struct page +0 (flags)
3.45% 0.06% 0.00% struct page +24 (mapping)
0.25% 0.28% 0.00% struct page +48 (_mapcount.counter)
0.02% 0.06% 0.00% struct page +32 (index)
0.02% 0.00% 0.00% struct page +52 (_refcount.counter)
0.02% 0.01% 0.00% struct page +56 (memcg_data)
0.00% 0.01% 0.00% struct page +16 (lru.prev)
15.37% 17.54% 0.00% (stack operation)
15.37% 17.54% 0.00% (stack operation) +0 (no field)
11.71% 50.27% 0.00% (unknown)
11.71% 50.27% 0.00% (unknown) +0 (no field)
$ perf annotate --data-type
...
Annotate type: 'struct cfs_rq' in [kernel.kallsyms] (13 samples):
============================================================================
samples offset size field
13 0 640 struct cfs_rq {
2 0 16 struct load_weight load {
2 0 8 unsigned long weight;
0 8 4 u32 inv_weight;
};
0 16 8 unsigned long runnable_weight;
0 24 4 unsigned int nr_running;
1 28 4 unsigned int h_nr_running;
...
$ perf annotate --data-type=page --group
Annotate type: 'struct page' in [kernel.kallsyms] (480 samples):
event[0] = cpu/mem-loads,ldlat=4/P
event[1] = cpu/mem-stores/P
event[2] = dummy:u
===================================================================================
samples offset size field
447 33 0 0 64 struct page {
108 8 0 0 8 long unsigned int flags;
319 13 0 8 40 union {
319 13 0 8 40 struct {
236 2 0 8 16 union {
236 2 0 8 16 struct list_head lru {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct {
236 1 0 8 8 void* __filler;
0 1 0 16 4 unsigned int mlock_count;
};
236 2 0 8 16 struct list_head buddy_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
236 2 0 8 16 struct list_head pcp_list {
236 1 0 8 8 struct list_head* next;
0 1 0 16 8 struct list_head* prev;
};
};
82 4 0 24 8 struct address_space* mapping;
1 7 0 32 8 union {
1 7 0 32 8 long unsigned int index;
1 7 0 32 8 long unsigned int share;
};
0 0 0 40 8 long unsigned int private;
};
This uses the existing annotate code, calling objdump to do the
disassembly, with improvements to avoid having this take too long,
but longer term a switch to a disassembler library, possibly
reusing code in the kernel will be pursued.
This is the initial implementation, please use it and report
impressions and bugs. Make sure the kernel-debuginfo packages match
the running kernel. The 'perf report' phase for non short perf.data
files may take a while.
There is a great article about it on LWN:
https://lwn.net/Articles/955709/ - "Data-type profiling for perf"
One last test I did while writing this text, on a AMD Ryzen 5950X,
using a distro kernel, while doing a simple 'find /' on an
otherwise idle system resulted in:
# uname -r
6.6.9-100.fc38.x86_64
# perf -vv | grep BPF_
bpf: [ on ] # HAVE_LIBBPF_SUPPORT
bpf_skeletons: [ on ] # HAVE_BPF_SKEL
# rpm -qa | grep kernel-debuginfo
kernel-debuginfo-common-x86_64-6.6.9-100.fc38.x86_64
kernel-debuginfo-6.6.9-100.fc38.x86_64
#
# perf mem record -a --filter 'mem_op == load || mem_op == store, ip > 0x8000000000000000'
^C[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 2.199 MB perf.data (2913 samples) ]
#
# ls -la perf.data
-rw-------. 1 root root 2346486 Jan 9 18:36 perf.data
# perf evlist
ibs_op//
dummy:u
# perf evlist -v
ibs_op//: type: 11, size: 136, config: 0, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|ADDR|CPU|PERIOD|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, disabled: 1, inherit: 1, freq: 1, sample_id_all: 1
dummy:u: type: 1 (PERF_TYPE_SOFTWARE), size: 136, config: 0x9 (PERF_COUNT_SW_DUMMY), { sample_period, sample_freq }: 1, sample_type: IP|TID|TIME|ADDR|CPU|IDENTIFIER|DATA_SRC|WEIGHT, read_format: ID, inherit: 1, exclude_kernel: 1, exclude_hv: 1, mmap: 1, comm: 1, task: 1, mmap_data: 1, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1
#
# perf report -s type,typeoff --hierarchy --group --stdio
# Total Lost Samples: 0
#
# Samples: 2K of events 'ibs_op//, dummy:u'
# Event count (approx.): 1904553038
#
# Overhead Data Type / Data Type Offset
# ................... ............................
#
73.70% 0.00% (unknown)
73.70% 0.00% (unknown) +0 (no field)
3.01% 0.00% long unsigned int
3.00% 0.00% long unsigned int +0 (no field)
0.01% 0.00% long unsigned int +2 (no field)
2.73% 0.00% struct task_struct
1.71% 0.00% struct task_struct +52 (on_cpu)
0.38% 0.00% struct task_struct +2104 (rcu_read_unlock_special.b.blocked)
0.23% 0.00% struct task_struct +2100 (rcu_read_lock_nesting)
0.14% 0.00% struct task_struct +2384 ()
0.06% 0.00% struct task_struct +3096 (signal)
0.05% 0.00% struct task_struct +3616 (cgroups)
0.05% 0.00% struct task_struct +2344 (active_mm)
0.02% 0.00% struct task_struct +46 (flags)
0.02% 0.00% struct task_struct +2096 (migration_disabled)
0.01% 0.00% struct task_struct +24 (__state)
0.01% 0.00% struct task_struct +3956 (mm_cid_active)
0.01% 0.00% struct task_struct +1048 (cpus_ptr)
0.01% 0.00% struct task_struct +184 (se.group_node.next)
0.01% 0.00% struct task_struct +20 (thread_info.cpu)
0.00% 0.00% struct task_struct +104 (on_rq)
0.00% 0.00% struct task_struct +2456 (pid)
1.36% 0.00% struct module
0.59% 0.00% struct module +952 (kallsyms)
0.42% 0.00% struct module +0 (state)
0.23% 0.00% struct module +8 (list.next)
0.12% 0.00% struct module +216 (syms)
0.95% 0.00% struct inode
0.41% 0.00% struct inode +40 (i_sb)
0.22% 0.00% struct inode +0 (i_mode)
0.06% 0.00% struct inode +76 (i_rdev)
0.06% 0.00% struct inode +56 (i_security)
<SNIP>
perf top/report:
- Don't ignore job control, allowing control+Z + bg to work.
- Add s390 raw data interpretation for PAI (Processor Activity
Instrumentation) counters.
perf archive:
- Add new option '--all' to pack perf.data with DSOs.
- Add new option '--unpack' to expand tarballs.
Initialization speedups:
- Lazily initialize zstd streams to save memory when not using it.
- Lazily allocate/size mmap event copy.
- Lazy load kernel symbols in 'perf record'.
- Be lazier in allocating lost samples buffer in 'perf record'.
- Don't synthesize BPF events when disabled via the command line
(perf record --no-bpf-event).
Assorted improvements:
- Show note on AMD systems that the :p, :pp, :ppp and :P are all the
same, as IBS (Instruction Based Sampling) is used and it is
inherentely precise, not having levels of precision like in Intel
systems.
- When 'cycles' isn't available, fall back to the "task-clock" event
when not system wide, not to 'cpu-clock'.
- Add --debug-file option to redirect debug output, e.g.:
$ perf --debug-file /tmp/perf.log record -v true
- Shrink 'struct map' to under one cacheline by avoiding function
pointers for selecting if addresses are identity or DSO relative,
and using just a byte for some boolean struct members.
- Resolve the arch specific strerrno just once to use in
perf_env__arch_strerrno().
- Reduce memory for recording PERF_RECORD_LOST_SAMPLES event.
Assorted fixes:
- Fix the default 'perf top' usage on Intel hybrid systems, now it
starts with a browser showing the number of samples for Efficiency
(cpu_atom/cycles/P) and Performance (cpu_core/cycles/P). This
behaviour is similar on ARM64, with its respective set of
big.LITTLE processors.
- Fix segfault on build_mem_topology() error path.
- Fix 'perf mem' error on hybrid related to availability of mem event
in a PMU.
- Fix missing reference count gets (map, maps) in the db-export code.
- Avoid recursively taking env->bpf_progs.lock in the 'perf_env'
code.
- Use the newly introduced maps__for_each_map() to add missing
locking around iteration of 'struct map' entries.
- Parse NOTE segments until the build id is found, don't stop on the
first one, ELF files may have several such NOTE segments.
- Remove 'egrep' usage, its deprecated, use 'grep -E' instead.
- Warn first about missing libelf, not libbpf, that depends on
libelf.
- Use alternative to 'find ... -printf' as this isn't supported in
busybox.
- Address python 3.6 DeprecationWarning for string scapes.
- Fix memory leak in uniq() in libsubcmd.
- Fix man page formatting for 'perf lock'
- Fix some spelling mistakes.
perf tests:
- Fail shell tests that needs some symbol in perf itself if it is
stripped. These tests check if a symbol is resolved, if some hot
function is indeed detected by profiling, etc.
- The 'perf test sigtrap' test is currently failing on PREEMPT_RT,
skip it if sleeping spinlocks are detected (using BTF) and point to
the mailing list discussion about it. This test is also being
skipped on several architectures (powerpc, s390x, arm and aarch64)
due to other pending issues with intruction breakpoints.
- Adjust test case perf record offcpu profiling tests for s390.
- Fix 'Setup struct perf_event_attr' fails on s390 on z/VM guest,
addressing issues caused by the fallback from cycles to task-clock
done in this release.
- Fix mask for VG register in the user-regs test.
- Use shellcheck on 'perf test' shell scripts automatically to make
sure changes don't introduce things it flags as problematic.
- Add option to change objdump binary and allow it to be set via
'perf config'.
- Add basic 'perf script', 'perf list --json" and 'perf diff' tests.
- Basic branch counter support.
- Make DSO tests a suite rather than individual.
- Remove atomics from test_loop to avoid test failures.
- Fix call chain match on powerpc for the record+probe_libc_inet_pton
test.
- Improve Intel hybrid tests.
Vendor event files (JSON):
powerpc:
- Update datasource event name to fix duplicate events on IBM's
Power10.
- Add PVN for HX-C2000 CPU with Power8 Architecture.
Intel:
- Alderlake/rocketlake metric fixes.
- Update emeraldrapids events to v1.02.
- Update icelakex events to v1.23.
- Update sapphirerapids events to v1.17.
- Add skx, clx, icx and spr upi bandwidth metric.
AMD:
- Add Zen 4 memory controller events.
RISC-V:
- Add StarFive Dubhe-80 and Dubhe-90 JSON files.
https://www.starfivetech.com/en/site/cpu-u
- Add T-HEAD C9xx JSON file.
https://github.com/riscv-software-src/opensbi/blob/master/docs/platform/thead-c9xx.md
ARM64:
- Remove UTF-8 characters from cmn.json, that were causing build
failure in some distros.
- Add core PMU events and metrics for Ampere One X.
- Rename Ampere One's BPU_FLUSH_MEM_FAULT to GPC_FLUSH_MEM_FAULT
libperf:
- Rename several perf_cpu_map constructor names to clarify what they
really do.
- Ditto for some other methods, coping with some issues in their
semantics, like perf_cpu_map__empty() ->
perf_cpu_map__has_any_cpu_or_is_empty().
- Document perf_cpu_map__nr()'s behavior
perf stat:
- Exit if parse groups fails.
- Combine the -A/--no-aggr and --no-merge options.
- Fix help message for --metric-no-threshold option.
Hardware tracing:
ARM64 CoreSight:
- Bump minimum OpenCSD version to ensure a bugfix is present.
- Add 'T' itrace option for timestamp trace
- Set start vm addr of exectable file to 0 and don't ignore first
sample on the arm-cs-trace-disasm.py 'perf script'"
* tag 'perf-tools-for-v6.8-1-2024-01-09' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (179 commits)
MAINTAINERS: Add Namhyung as tools/perf/ co-maintainer
perf test: test case 'Setup struct perf_event_attr' fails on s390 on z/vm
perf db-export: Fix missing reference count get in call_path_from_sample()
perf tests: Add perf script test
libsubcmd: Fix memory leak in uniq()
perf TUI: Don't ignore job control
perf vendor events intel: Update sapphirerapids events to v1.17
perf vendor events intel: Update icelakex events to v1.23
perf vendor events intel: Update emeraldrapids events to v1.02
perf vendor events intel: Alderlake/rocketlake metric fixes
perf x86 test: Add hybrid test for conflicting legacy/sysfs event
perf x86 test: Update hybrid expectations
perf vendor events amd: Add Zen 4 memory controller events
perf stat: Fix hard coded LL miss units
perf record: Reduce memory for recording PERF_RECORD_LOST_SAMPLES event
perf env: Avoid recursively taking env->bpf_progs.lock
perf annotate: Add --insn-stat option for debugging
perf annotate: Add --type-stat option for debugging
perf annotate: Support event group display
perf annotate: Add --data-type option
...
|
||
|
Andrii Nakryiko
|
76ec90a996 |
libbpf: warn on unexpected __arg_ctx type when rewriting BTF
On kernel that don't support arg:ctx tag, before adjusting global subprog BTF information to match kernel's expected canonical type names, make sure that types used by user are meaningful, and if not, warn and don't do BTF adjustments. This is similar to checks that kernel performs, but narrower in scope, as only a small subset of BPF program types can be accommodated by libbpf using canonical type names. Libbpf unconditionally allows `struct pt_regs *` for perf_event program types, unlike kernel, which supports that conditionally on architecture. This is done to keep things simple and not cause unnecessary false positives. This seems like a minor and harmless deviation, which in real-world programs will be caught by kernels with arg:ctx tag support anyways. So KISS principle. This logic is hard to test (especially on latest kernels), so manual testing was performed instead. Libbpf emitted the following warning for perf_event program with wrong context argument type: libbpf: prog 'arg_tag_ctx_perf': subprog 'subprog_ctx_tag' arg#0 is expected to be of `struct bpf_perf_event_data *` type Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
01b55f4f0c |
libbpf: feature-detect arg:ctx tag support in kernel
Add feature detector of kernel-side arg:ctx (__arg_ctx) tag support. If this is detected, libbpf will avoid doing any __arg_ctx-related BTF rewriting and checks in favor of letting kernel handle this completely. test_global_funcs/ctx_arg_rewrite subtest is adjusted to do the same feature detection (albeit in much simpler, though round-about and inefficient, way), and skip the tests. This is done to still be able to execute this test on older kernels (like in libbpf CI). Note, BPF token series ([0]) does a major refactor and code moving of libbpf-internal feature detection "framework", so to avoid unnecessary conflicts we keep newly added feature detection stand-alone with ad-hoc result caching. Once things settle, there will be a small follow up to re-integrate everything back and move code into its final place in newly-added (by BPF token series) features.c file. [0] https://patchwork.kernel.org/project/netdevbpf/list/?series=814209&state=* Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Ian Rogers
|
ad30469a84 |
libsubcmd: Fix memory leak in uniq()
uniq() will write one command name over another causing the overwritten string to be leaked. Fix by doing a pass that removes duplicates and a second that removes the holes. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Chenyuan Mi <cymi20@fudan.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20231208000515.1693746-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Andrii Nakryiko
|
2f38fe6894 |
libbpf: implement __arg_ctx fallback logic
Out of all special global func arg tag annotations, __arg_ctx is
practically is the most immediately useful and most critical to have
working across multitude kernel version, if possible. This would allow
end users to write much simpler code if __arg_ctx semantics worked for
older kernels that don't natively understand btf_decl_tag("arg:ctx") in
verifier logic.
Luckily, it is possible to ensure __arg_ctx works on old kernels through
a bit of extra work done by libbpf, at least in a lot of common cases.
To explain the overall idea, we need to go back at how context argument
was supported in global funcs before __arg_ctx support was added. This
was done based on special struct name checks in kernel. E.g., for
BPF_PROG_TYPE_PERF_EVENT the expectation is that argument type `struct
bpf_perf_event_data *` mark that argument as PTR_TO_CTX. This is all
good as long as global function is used from the same BPF program types
only, which is often not the case. If the same subprog has to be called
from, say, kprobe and perf_event program types, there is no single
definition that would satisfy BPF verifier. Subprog will have context
argument either for kprobe (if using bpf_user_pt_regs_t struct name) or
perf_event (with bpf_perf_event_data struct name), but not both.
This limitation was the reason to add btf_decl_tag("arg:ctx"), making
the actual argument type not important, so that user can just define
"generic" signature:
__noinline int global_subprog(void *ctx __arg_ctx) { ... }
I won't belabor how libbpf is implementing subprograms, see a huge
comment next to bpf_object_relocate_calls() function. The idea is that
each main/entry BPF program gets its own copy of global_subprog's code
appended.
This per-program copy of global subprog code *and* associated func_info
.BTF.ext information, pointing to FUNC -> FUNC_PROTO BTF type chain
allows libbpf to simulate __arg_ctx behavior transparently, even if the
kernel doesn't yet support __arg_ctx annotation natively.
The idea is straightforward: each time we append global subprog's code
and func_info information, we adjust its FUNC -> FUNC_PROTO type
information, if necessary (that is, libbpf can detect the presence of
btf_decl_tag("arg:ctx") just like BPF verifier would do it).
The rest is just mechanical and somewhat painful BTF manipulation code.
It's painful because we need to clone FUNC -> FUNC_PROTO, instead of
reusing it, as same FUNC -> FUNC_PROTO chain might be used by another
main BPF program within the same BPF object, so we can't just modify it
in-place (and cloning BTF types within the same struct btf object is
painful due to constant memory invalidation, see comments in code).
Uploaded BPF object's BTF information has to work for all BPF
programs at the same time.
Once we have FUNC -> FUNC_PROTO clones, we make sure that instead of
using some `void *ctx` parameter definition, we have an expected `struct
bpf_perf_event_data *ctx` definition (as far as BPF verifier and kernel
is concerned), which will mark it as context for BPF verifier. Same
global subprog relocated and copied into another main BPF program will
get different type information according to main program's type. It all
works out in the end in a completely transparent way for end user.
Libbpf maintains internal program type -> expected context struct name
mapping internally. Note, not all BPF program types have named context
struct, so this approach won't work for such programs (just like it
didn't before __arg_ctx). So native __arg_ctx is still important to have
in kernel to have generic context support across all BPF program types.
Acked-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240104013847.3875810-8-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Andrii Nakryiko
|
1004742d7f |
libbpf: move BTF loading step after relocation step
With all the preparations in previous patches done we are ready to postpone BTF loading and sanitization step until after all the relocations are performed. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
fb03be7c4a |
libbpf: move exception callbacks assignment logic into relocation step
Move the logic of finding and assigning exception callback indices from BTF sanitization step to program relocations step, which seems more logical and will unblock moving BTF loading to after relocation step. Exception callbacks discovery and assignment has no dependency on BTF being loaded into the kernel, it only uses BTF information. It does need to happen before subprogram relocations happen, though. Which is why the split. No functional changes. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
dac645b950 |
libbpf: use stable map placeholder FDs
Move map creation to later during BPF object loading by pre-creating stable placeholder FDs (utilizing memfd_create()). Use dup2() syscall to then atomically make those placeholder FDs point to real kernel BPF map objects. This change allows to delay BPF map creation to after all the BPF program relocations. That, in turn, allows to delay BTF finalization and loading into kernel to after all the relocations as well. We'll take advantage of the latter in subsequent patches to allow libbpf to adjust BTF in a way that helps with BPF global function usage. Clean up a few places where we close map->fd, which now shouldn't happen, because map->fd should be a valid FD regardless of whether map was created or not. Surprisingly and nicely it simplifies a bunch of error handling code. If this change doesn't backfire, I'm tempted to pre-create such stable FDs for other entities (progs, maybe even BTF). We previously did some manipulations to make gen_loader work with fake map FDs, with stable map FDs this hack is not necessary for maps (we still have it for BTF, but I left it as is for now). Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
f08c18e083 |
libbpf: don't rely on map->fd as an indicator of map being created
With the upcoming switch to preallocated placeholder FDs for maps, switch various getters/setter away from checking map->fd. Use map_is_created() helper that detect whether BPF map can be modified based on map->obj->loaded state, with special provision for maps set up with bpf_map__reuse_fd(). For backwards compatibility, we take map_is_created() into account in bpf_map__fd() getter as well. This way before bpf_object__load() phase bpf_map__fd() will always return -1, just as before the changes in subsequent patches adding stable map->fd placeholders. We also get rid of all internal uses of bpf_map__fd() getter, as it's more oriented for uses external to libbpf. The above map_is_created() check actually interferes with some of the internal uses, if map FD is fetched through bpf_map__fd(). Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
fa98b54bff |
libbpf: use explicit map reuse flag to skip map creation steps
Instead of inferring whether map already point to previously created/pinned BPF map (which user can specify with bpf_map__reuse_fd()) API), use explicit map->reused flag that is set in such case. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
df7c3f7d3a |
libbpf: make uniform use of btf__fd() accessor inside libbpf
It makes future grepping and code analysis a bit easier. Acked-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240104013847.3875810-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
Mingyi Zhang
|
fc3a5534e2 |
libbpf: Fix NULL pointer dereference in bpf_object__collect_prog_relos
An issue occurred while reading an ELF file in libbpf.c during fuzzing: Program received signal SIGSEGV, Segmentation fault. 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206 4206 in libbpf.c (gdb) bt #0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206 #1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706 #2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437 #3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497 #4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16 #5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one () #6 0x000000000087ad92 in tracing::span::Span::in_scope () #7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir () #8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} () #9 0x00000000005f2601 in main () (gdb) scn_data was null at this code(tools/lib/bpf/src/libbpf.c): if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) { The scn_data is derived from the code above: scn = elf_sec_by_idx(obj, sec_idx); scn_data = elf_sec_data(obj, scn); relo_sec_name = elf_sec_str(obj, shdr->sh_name); sec_name = elf_sec_name(obj, scn); if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL return -EINVAL; In certain special scenarios, such as reading a malformed ELF file, it is possible that scn_data may be a null pointer Signed-off-by: Mingyi Zhang <zhangmingyi5@huawei.com> Signed-off-by: Xin Liu <liuxin350@huawei.com> Signed-off-by: Changye Wu <wuchangye@huawei.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com |
||
Alyssa Ross
|
812d8bf876 |
libbpf: Skip DWARF sections in linker sanity check
clang can generate (with -g -Wa,--compress-debug-sections) 4-byte aligned DWARF sections that declare themselves to be 8-byte aligned in the section header. Since DWARF sections are dropped during linking anyway, just skip running the sanity checks on them. Reported-by: Sergei Trofimovich <slyich@gmail.com> Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Alyssa Ross <hi@alyssa.is> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Closes: https://lore.kernel.org/bpf/ZXcFRJVKbKxtEL5t@nz.home/ Link: https://lore.kernel.org/bpf/20231219110324.8989-1-hi@alyssa.is |
||
|
Andrii Nakryiko
|
aae9c25dda |
libbpf: add __arg_xxx macros for annotating global func args
Add a set of __arg_xxx macros which can be used to augment BPF global subprogs/functions with extra information for use by BPF verifier. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
d17aff807f |
Revert BPF token-related functionality
This patch includes the following revert (one conflicting BPF FS patch and three token patch sets, represented by merge commits): - revert |
||
Arnaldo Carvalho de Melo
|
ab1c247094 |
Merge remote-tracking branch 'torvalds/master' into perf-tools-next
To pick up fixes that went thru perf-tools for v6.7 and to get in sync with upstream to check for drift in the copies of headers, etc. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
67bc993446 |
libperf cpumap: Document perf_cpu_map__nr()'s behavior
perf_cpu_map__nr()'s behavior around an empty CPU map is strange as it returns that there is 1 CPU. Changing code that may rely on this behavior is hard, we can at least document the behavior. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Link: https://lore.kernel.org/r/20231129060211.1890454-15-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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Andrii Nakryiko
|
ed54124b88 |
libbpf: support BPF token path setting through LIBBPF_BPF_TOKEN_PATH envvar
To allow external admin authority to override default BPF FS location (/sys/fs/bpf) for implicit BPF token creation, teach libbpf to recognize LIBBPF_BPF_TOKEN_PATH envvar. If it is specified and user application didn't explicitly specify neither bpf_token_path nor bpf_token_fd option, it will be treated exactly like bpf_token_path option, overriding default /sys/fs/bpf location and making BPF token mandatory. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-10-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Andrii Nakryiko
|
1d0dd6ea2e |
libbpf: wire up BPF token support at BPF object level
Add BPF token support to BPF object-level functionality.
BPF token is supported by BPF object logic either as an explicitly
provided BPF token from outside (through BPF FS path or explicit BPF
token FD), or implicitly (unless prevented through
bpf_object_open_opts).
Implicit mode is assumed to be the most common one for user namespaced
unprivileged workloads. The assumption is that privileged container
manager sets up default BPF FS mount point at /sys/fs/bpf with BPF token
delegation options (delegate_{cmds,maps,progs,attachs} mount options).
BPF object during loading will attempt to create BPF token from
/sys/fs/bpf location, and pass it for all relevant operations
(currently, map creation, BTF load, and program load).
In this implicit mode, if BPF token creation fails due to whatever
reason (BPF FS is not mounted, or kernel doesn't support BPF token,
etc), this is not considered an error. BPF object loading sequence will
proceed with no BPF token.
In explicit BPF token mode, user provides explicitly either custom BPF
FS mount point path or creates BPF token on their own and just passes
token FD directly. In such case, BPF object will either dup() token FD
(to not require caller to hold onto it for entire duration of BPF object
lifetime) or will attempt to create BPF token from provided BPF FS
location. If BPF token creation fails, that is considered a critical
error and BPF object load fails with an error.
Libbpf provides a way to disable implicit BPF token creation, if it
causes any troubles (BPF token is designed to be completely optional and
shouldn't cause any problems even if provided, but in the world of BPF
LSM, custom security logic can be installed that might change outcome
dependin on the presence of BPF token). To disable libbpf's default BPF
token creation behavior user should provide either invalid BPF token FD
(negative), or empty bpf_token_path option.
BPF token presence can influence libbpf's feature probing, so if BPF
object has associated BPF token, feature probing is instructed to use
BPF object-specific feature detection cache and token FD.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231213190842.3844987-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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Andrii Nakryiko
|
a75bb6a165 |
libbpf: wire up token_fd into feature probing logic
Adjust feature probing callbacks to take into account optional token_fd. In unprivileged contexts, some feature detectors would fail to detect kernel support just because BPF program, BPF map, or BTF object can't be loaded due to privileged nature of those operations. So when BPF object is loaded with BPF token, this token should be used for feature probing. This patch is setting support for this scenario, but we don't yet pass non-zero token FD. This will be added in the next patch. We also switched BPF cookie detector from using kprobe program to tracepoint one, as tracepoint is somewhat less dangerous BPF program type and has higher likelihood of being allowed through BPF token in the future. This change has no effect on detection behavior. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Andrii Nakryiko
|
ab8fc393b2 |
libbpf: move feature detection code into its own file
It's quite a lot of well isolated code, so it seems like a good candidate to move it out of libbpf.c to reduce its size. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Andrii Nakryiko
|
29c302a2e2 |
libbpf: further decouple feature checking logic from bpf_object
Add feat_supported() helper that accepts feature cache instead of bpf_object. This allows low-level code in bpf.c to not know or care about higher-level concept of bpf_object, yet it will be able to utilize custom feature checking in cases where BPF token might influence the outcome. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Andrii Nakryiko
|
c6c5be3eee |
libbpf: split feature detectors definitions from cached results
Split a list of supported feature detectors with their corresponding callbacks from actual cached supported/missing values. This will allow to have more flexible per-token or per-object feature detectors in subsequent refactorings. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
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Daniel Xu
|
2f70803532 |
libbpf: Add BPF_CORE_WRITE_BITFIELD() macro
=== Motivation ===
Similar to reading from CO-RE bitfields, we need a CO-RE aware bitfield
writing wrapper to make the verifier happy.
Two alternatives to this approach are:
1. Use the upcoming `preserve_static_offset` [0] attribute to disable
CO-RE on specific structs.
2. Use broader byte-sized writes to write to bitfields.
(1) is a bit hard to use. It requires specific and not-very-obvious
annotations to bpftool generated vmlinux.h. It's also not generally
available in released LLVM versions yet.
(2) makes the code quite hard to read and write. And especially if
BPF_CORE_READ_BITFIELD() is already being used, it makes more sense to
to have an inverse helper for writing.
=== Implementation details ===
Since the logic is a bit non-obvious, I thought it would be helpful
to explain exactly what's going on.
To start, it helps by explaining what LSHIFT_U64 (lshift) and RSHIFT_U64
(rshift) is designed to mean. Consider the core of the
BPF_CORE_READ_BITFIELD() algorithm:
val <<= __CORE_RELO(s, field, LSHIFT_U64);
val = val >> __CORE_RELO(s, field, RSHIFT_U64);
Basically what happens is we lshift to clear the non-relevant (blank)
higher order bits. Then we rshift to bring the relevant bits (bitfield)
down to LSB position (while also clearing blank lower order bits). To
illustrate:
Start: ........XXX......
Lshift: XXX......00000000
Rshift: 00000000000000XXX
where `.` means blank bit, `0` means 0 bit, and `X` means bitfield bit.
After the two operations, the bitfield is ready to be interpreted as a
regular integer.
Next, we want to build an alternative (but more helpful) mental model
on lshift and rshift. That is, to consider:
* rshift as the total number of blank bits in the u64
* lshift as number of blank bits left of the bitfield in the u64
Take a moment to consider why that is true by consulting the above
diagram.
With this insight, we can now define the following relationship:
bitfield
_
| |
0.....00XXX0...00
| | | |
|______| | |
lshift | |
|____|
(rshift - lshift)
That is, we know the number of higher order blank bits is just lshift.
And the number of lower order blank bits is (rshift - lshift).
Finally, we can examine the core of the write side algorithm:
mask = (~0ULL << rshift) >> lshift; // 1
val = (val & ~mask) | ((nval << rpad) & mask); // 2
1. Compute a mask where the set bits are the bitfield bits. The first
left shift zeros out exactly the number of blank bits, leaving a
bitfield sized set of 1s. The subsequent right shift inserts the
correct amount of higher order blank bits.
2. On the left of the `|`, mask out the bitfield bits. This creates
0s where the new bitfield bits will go. On the right of the `|`,
bring nval into the correct bit position and mask out any bits
that fall outside of the bitfield. Finally, by bor'ing the two
halves, we get the final set of bits to write back.
[0]: https://reviews.llvm.org/D133361
Co-developed-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Co-developed-by: Jonathan Lemon <jlemon@aviatrix.com>
Signed-off-by: Jonathan Lemon <jlemon@aviatrix.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Link: https://lore.kernel.org/r/4d3dd215a4fd57d980733886f9c11a45e1a9adf3.1702325874.git.dxu@dxuuu.xyz
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
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|
Ian Rogers
|
5805c82513 |
libperf cpumap: Add for_each_cpu() that skips the "any CPU" case
When iterating CPUs in a CPU map it is often desirable to skip the "any CPU" (aka dummy) case. Add a helper for this and use in builtin-record. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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|
Ian Rogers
|
effe957c6b |
libperf cpumap: Replace usage of perf_cpu_map__new(NULL) with perf_cpu_map__new_online_cpus()
Passing NULL to perf_cpu_map__new() performs perf_cpu_map__new_online_cpus(), just directly call perf_cpu_map__new_online_cpus() to be more intention revealing. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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|
Ian Rogers
|
923ca62a7b |
libperf cpumap: Rename perf_cpu_map__empty() to perf_cpu_map__has_any_cpu_or_is_empty()
The name perf_cpu_map_empty is misleading as true is also returned when the map contains an "any" CPU (aka dummy) map. Rename to perf_cpu_map__has_any_cpu_or_is_empty(), later changes will (re)introduce perf_cpu_map__empty() and perf_cpu_map__has_any_cpu(). Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-4-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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|
Ian Rogers
|
8f60f870a9 |
libperf cpumap: Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() and prefer sysfs
Rename perf_cpu_map__default_new() to perf_cpu_map__new_online_cpus() to better indicate what the implementation does. Read the online CPUs from /sys/devices/system/cpu/online first before using sysconf() as it can't accurately configure holes in the CPU map. If sysconf() is used, warn when the configured and online processors disagree. When reading from a file, if the read doesn't yield a CPU map then return an empty map rather than the default online. This avoids recursion but also better yields being able to detect failures. Add more comments. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-3-irogers@google.com [ s/syfs/sysfs/g typo ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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|
Ian Rogers
|
48219b089d |
libperf cpumap: Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu()
Rename perf_cpu_map__dummy_new() to perf_cpu_map__new_any_cpu() to better indicate this is creating a CPU map for the perf_event_open "any" CPU case. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-2-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
Sergei Trofimovich
|
32fa058398 |
libbpf: Add pr_warn() for EINVAL cases in linker_sanity_check_elf
Before the change on `i686-linux` `systemd` build failed as:
$ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o': Invalid argument (22)
After the change it fails as:
$ bpftool gen object src/core/bpf/socket_bind/socket-bind.bpf.o src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
libbpf: ELF section #9 has inconsistent alignment addr=8 != d=4 in src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o
Error: failed to link 'src/core/bpf/socket_bind/socket-bind.bpf.unstripped.o': Invalid argument (22)
Now it's slightly easier to figure out what is wrong with an ELF file.
Signed-off-by: Sergei Trofimovich <slyich@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20231208215100.435876-1-slyich@gmail.com
|
||
David Vernet
|
8b7b0e5fe4 |
bpf: Load vmlinux btf for any struct_ops map
In libbpf, when determining whether we need to load vmlinux btf, we're
currently (among other things) checking whether there is any struct_ops
program present in the object. This works for most realistic struct_ops
maps, as a struct_ops map is of course typically composed of one or more
struct_ops programs. However, that technically need not be the case. A
struct_ops interface could be defined which allows a map to be specified
which one or more non-prog fields, and which provides default behavior
if no struct_ops progs is actually provided otherwise. For sched_ext,
for example, you technically only need to specify the name of the
scheduler in the struct_ops map, with the core scheduler logic providing
default behavior if no prog is actually specified.
If we were to define and try to load such a struct_ops map, we would
crash in libbpf when initializing it as obj->btf_vmlinux will be NULL:
Reading symbols from minimal...
(gdb) r
Starting program: minimal_example
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/usr/lib/libthread_db.so.1".
Program received signal SIGSEGV, Segmentation fault.
0x000055555558308c in btf__type_cnt (btf=0x0) at btf.c:612
612 return btf->start_id + btf->nr_types;
(gdb) bt
type_name=0x5555555d99e3 "sched_ext_ops", kind=4) at btf.c:914
kind=4) at btf.c:942
type=0x7fffffffe558, type_id=0x7fffffffe548, ...
data_member=0x7fffffffe568) at libbpf.c:948
kern_btf=0x0) at libbpf.c:1017
at libbpf.c:8059
So as to account for such bare-bones struct_ops maps, let's update
obj_needs_vmlinux_btf() to also iterate over an obj's maps and check
whether any of them are struct_ops maps.
Signed-off-by: David Vernet <void@manifault.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Link: https://lore.kernel.org/bpf/20231208061704.400463-1-void@manifault.com
|
||
|
Andrii Nakryiko
|
1571740a9b |
libbpf: add BPF token support to bpf_prog_load() API
Wire through token_fd into bpf_prog_load(). Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-16-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
1a8df7fa00 |
libbpf: add BPF token support to bpf_btf_load() API
Allow user to specify token_fd for bpf_btf_load() API that wraps kernel's BPF_BTF_LOAD command. This allows loading BTF from unprivileged process as long as it has BPF token allowing BPF_BTF_LOAD command, which can be created and delegated by privileged process. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-15-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
37891cea66 |
libbpf: add BPF token support to bpf_map_create() API
Add ability to provide token_fd for BPF_MAP_CREATE command through bpf_map_create() API. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-14-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
ecd435143e |
libbpf: add bpf_token_create() API
Add low-level wrapper API for BPF_TOKEN_CREATE command in bpf() syscall. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-13-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Ian Rogers
|
f8846a1a3c |
tools api fs: Avoid reading whole file for a 1 byte bool
sysfs__read_bool() used the first byte from a fully read file into a string. It then looked at the first byte's value. Avoid doing this and just read the first byte. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
b6a15269ce |
tools api fs: Switch filename__read_str to use io.h
filename__read_str() has its own string reading code that allocates memory before reading into it. The memory allocated is sized at BUFSIZ that is 8kb. Most strings are short and so most of this 8kb is wasted. Refactor io__getline(), as io__getdelim(), so that the newline character can be configurable and ignored in the case of filename__read_str(). Code like build_caches_for_cpu() in perf's header.c will read many strings and hold them in a data structure, in this case multiple strings per cache level per CPU. Using io.h's io__getline() avoids the wasted memory as strings are temporarily read into a buffer on the stack before being copied to a buffer that grows 128 bytes at a time and is never sized larger than the string. For a 16 hyperthread system the memory consumption of "perf record true" is reduced by 180kb, primarily through saving memory when reading the cache information. Signed-off-by: Ian Rogers <irogers@google.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Colin Ian King <colin.i.king@gmail.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez <german.gomez@arm.com> Cc: Guilherme Amadio <amadio@gentoo.org> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Li Dong <lidong@vivo.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Ming Wang <wangming01@loongson.cn> Cc: Nick Terrell <terrelln@fb.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Vincent Whitchurch <vincent.whitchurch@axis.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Link: https://lore.kernel.org/r/20231127220902.1315692-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
||
|
Ian Rogers
|
366efbff58 |
libperf: Lazily allocate/size mmap event copy
The event copy in the mmap is used to have storage to read an event. Not
all users of mmaps read the events, such as perf record. The amount of
buffer was also statically set to PERF_SAMPLE_MAX_SIZE rather than the
amount necessary from the header's event size.
Switch to a model where the event_copy is reallocated if too small to
the event's size. This adds the potential for the event to move, so if a
copy of the event pointer were stored it could be broken. All the
current users do:
while(event = perf_mmap__read_event()) { ... }
and so they would be broken due to the event being overwritten if they
had stored the pointer. Manual inspection and address sanitizer testing
also shows the event pointer not being stored.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Li Dong <lidong@vivo.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20231127220902.1315692-3-irogers@google.com
[ Replace two lines with equivalent zfree(&map->event_copy) ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
|
||
|
Arnaldo Carvalho de Melo
|
af76b2dec0 |
libapi: Add missing linux/types.h header to get the __u64 type on io.h
There are functions using __u64, so we need to have the linux/types.h
header otherwise we'll break when its not included before api/io.h.
Fixes:
|
||
Jiri Olsa
|
48f0dfd8d3 |
libbpf: Add st_type argument to elf_resolve_syms_offsets function
We need to get offsets for static variables in following changes, so making elf_resolve_syms_offsets to take st_type value as argument and passing it to elf_sym_iter_new. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20231125193130.834322-2-jolsa@kernel.org |
||
|
Eduard Zingerman
|
b8d78cb2e2 |
libbpf: Start v1.4 development cycle
Bump libbpf.map to v1.4.0 to start a new libbpf version cycle. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231123000439.12025-1-eddyz87@gmail.com |
||
Yonghong Song
|
7f7c43693c |
libbpf: Fix potential uninitialized tail padding with LIBBPF_OPTS_RESET
Martin reported that there is a libbpf complaining of non-zero-value tail
padding with LIBBPF_OPTS_RESET macro if struct bpf_netkit_opts is modified
to have a 4-byte tail padding. This only happens to clang compiler.
The commend line is: ./test_progs -t tc_netkit_multi_links
Martin and I did some investigation and found this indeed the case and
the following are the investigation details.
Clang:
clang version 18.0.0
<I tried clang15/16/17 and they all have similar results>
tools/lib/bpf/libbpf_common.h:
#define LIBBPF_OPTS_RESET(NAME, ...) \
do { \
memset(&NAME, 0, sizeof(NAME)); \
NAME = (typeof(NAME)) { \
.sz = sizeof(NAME), \
__VA_ARGS__ \
}; \
} while (0)
#endif
tools/lib/bpf/libbpf.h:
struct bpf_netkit_opts {
/* size of this struct, for forward/backward compatibility */
size_t sz;
__u32 flags;
__u32 relative_fd;
__u32 relative_id;
__u64 expected_revision;
size_t :0;
};
#define bpf_netkit_opts__last_field expected_revision
In the above struct bpf_netkit_opts, there is no tail padding.
prog_tests/tc_netkit.c:
static void serial_test_tc_netkit_multi_links_target(int mode, int target)
{
...
LIBBPF_OPTS(bpf_netkit_opts, optl);
...
LIBBPF_OPTS_RESET(optl,
.flags = BPF_F_BEFORE,
.relative_fd = bpf_program__fd(skel->progs.tc1),
);
...
}
Let us make the following source change, note that we have a 4-byte
tailing padding now.
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index 6cd9c501624f..0dd83910ae9a 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -803,13 +803,13 @@ bpf_program__attach_tcx(const struct bpf_program *prog, int ifindex,
struct bpf_netkit_opts {
/* size of this struct, for forward/backward compatibility */
size_t sz;
- __u32 flags;
__u32 relative_fd;
__u32 relative_id;
__u64 expected_revision;
+ __u32 flags;
size_t :0;
};
-#define bpf_netkit_opts__last_field expected_revision
+#define bpf_netkit_opts__last_field flags
The clang 18 generated asm code looks like below:
; LIBBPF_OPTS_RESET(optl,
55e3: 48 8d 7d 98 leaq -0x68(%rbp), %rdi
55e7: 31 f6 xorl %esi, %esi
55e9: ba 20 00 00 00 movl $0x20, %edx
55ee: e8 00 00 00 00 callq 0x55f3 <serial_test_tc_netkit_multi_links_target+0x18d3>
55f3: 48 c7 85 10 fd ff ff 20 00 00 00 movq $0x20, -0x2f0(%rbp)
55fe: 48 8b 85 68 ff ff ff movq -0x98(%rbp), %rax
5605: 48 8b 78 18 movq 0x18(%rax), %rdi
5609: e8 00 00 00 00 callq 0x560e <serial_test_tc_netkit_multi_links_target+0x18ee>
560e: 89 85 18 fd ff ff movl %eax, -0x2e8(%rbp)
5614: c7 85 1c fd ff ff 00 00 00 00 movl $0x0, -0x2e4(%rbp)
561e: 48 c7 85 20 fd ff ff 00 00 00 00 movq $0x0, -0x2e0(%rbp)
5629: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
5633: 48 8b 85 10 fd ff ff movq -0x2f0(%rbp), %rax
563a: 48 89 45 98 movq %rax, -0x68(%rbp)
563e: 48 8b 85 18 fd ff ff movq -0x2e8(%rbp), %rax
5645: 48 89 45 a0 movq %rax, -0x60(%rbp)
5649: 48 8b 85 20 fd ff ff movq -0x2e0(%rbp), %rax
5650: 48 89 45 a8 movq %rax, -0x58(%rbp)
5654: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565b: 48 89 45 b0 movq %rax, -0x50(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
At -O0 level, the clang compiler creates an intermediate copy.
We have below to store 'flags' with 4-byte store and leave another 4 byte
in the same 8-byte-aligned storage undefined,
5629: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
and later we store 8-byte to the original zero'ed buffer
5654: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565b: 48 89 45 b0 movq %rax, -0x50(%rbp)
This caused a problem as the 4-byte value at [%rbp-0x2dc, %rbp-0x2e0)
may be garbage.
gcc (gcc 11.4) does not have this issue as it does zeroing struct first before
doing assignments:
; LIBBPF_OPTS_RESET(optl,
50fd: 48 8d 85 40 fc ff ff leaq -0x3c0(%rbp), %rax
5104: ba 20 00 00 00 movl $0x20, %edx
5109: be 00 00 00 00 movl $0x0, %esi
510e: 48 89 c7 movq %rax, %rdi
5111: e8 00 00 00 00 callq 0x5116 <serial_test_tc_netkit_multi_links_target+0x1522>
5116: 48 8b 45 f0 movq -0x10(%rbp), %rax
511a: 48 8b 40 18 movq 0x18(%rax), %rax
511e: 48 89 c7 movq %rax, %rdi
5121: e8 00 00 00 00 callq 0x5126 <serial_test_tc_netkit_multi_links_target+0x1532>
5126: 48 c7 85 40 fc ff ff 00 00 00 00 movq $0x0, -0x3c0(%rbp)
5131: 48 c7 85 48 fc ff ff 00 00 00 00 movq $0x0, -0x3b8(%rbp)
513c: 48 c7 85 50 fc ff ff 00 00 00 00 movq $0x0, -0x3b0(%rbp)
5147: 48 c7 85 58 fc ff ff 00 00 00 00 movq $0x0, -0x3a8(%rbp)
5152: 48 c7 85 40 fc ff ff 20 00 00 00 movq $0x20, -0x3c0(%rbp)
515d: 89 85 48 fc ff ff movl %eax, -0x3b8(%rbp)
5163: c7 85 58 fc ff ff 08 00 00 00 movl $0x8, -0x3a8(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
It is not clear how to resolve the compiler code generation as the compiler
generates correct code w.r.t. how to handle unnamed padding in C standard.
So this patch changed LIBBPF_OPTS_RESET macro to avoid uninitialized tail
padding. We already knows LIBBPF_OPTS macro works on both gcc and clang,
even with tail padding. So LIBBPF_OPTS_RESET is changed to be a
LIBBPF_OPTS followed by a memcpy(), thus avoiding uninitialized tail padding.
The below is asm code generated with this patch and with clang compiler:
; LIBBPF_OPTS_RESET(optl,
55e3: 48 8d bd 10 fd ff ff leaq -0x2f0(%rbp), %rdi
55ea: 31 f6 xorl %esi, %esi
55ec: ba 20 00 00 00 movl $0x20, %edx
55f1: e8 00 00 00 00 callq 0x55f6 <serial_test_tc_netkit_multi_links_target+0x18d6>
55f6: 48 c7 85 10 fd ff ff 20 00 00 00 movq $0x20, -0x2f0(%rbp)
5601: 48 8b 85 68 ff ff ff movq -0x98(%rbp), %rax
5608: 48 8b 78 18 movq 0x18(%rax), %rdi
560c: e8 00 00 00 00 callq 0x5611 <serial_test_tc_netkit_multi_links_target+0x18f1>
5611: 89 85 18 fd ff ff movl %eax, -0x2e8(%rbp)
5617: c7 85 1c fd ff ff 00 00 00 00 movl $0x0, -0x2e4(%rbp)
5621: 48 c7 85 20 fd ff ff 00 00 00 00 movq $0x0, -0x2e0(%rbp)
562c: c7 85 28 fd ff ff 08 00 00 00 movl $0x8, -0x2d8(%rbp)
5636: 48 8b 85 10 fd ff ff movq -0x2f0(%rbp), %rax
563d: 48 89 45 98 movq %rax, -0x68(%rbp)
5641: 48 8b 85 18 fd ff ff movq -0x2e8(%rbp), %rax
5648: 48 89 45 a0 movq %rax, -0x60(%rbp)
564c: 48 8b 85 20 fd ff ff movq -0x2e0(%rbp), %rax
5653: 48 89 45 a8 movq %rax, -0x58(%rbp)
5657: 48 8b 85 28 fd ff ff movq -0x2d8(%rbp), %rax
565e: 48 89 45 b0 movq %rax, -0x50(%rbp)
; link = bpf_program__attach_netkit(skel->progs.tc2, ifindex, &optl);
In the above code, a temporary buffer is zeroed and then has proper value assigned.
Finally, values in temporary buffer are copied to the original variable buffer,
hence tail padding is guaranteed to be 0.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Tested-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/bpf/20231107201511.2548645-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Linus Torvalds
|
7ab89417ed |
perf tools changes for v6.7
Build
-----
* Compile BPF programs by default if clang (>= 12.0.1) is available to
enable more features like kernel lock contention, off-cpu profiling,
kwork, sample filtering and so on. It can be disabled by passing
BUILD_BPF_SKEL=0 to make.
* Produce better error messages for bison on debug build (make DEBUG=1)
by defining YYDEBUG symbol internally.
perf record
-----------
* Track sideband events (like FORK/MMAP) from all CPUs even if perf record
targets a subset of CPUs only (using -C option). Otherwise it may lose
some information happened on a CPU out of the target list.
* Fix checking raw sched_switch tracepoint argument using system BTF.
This affects off-cpu profiling which attaches a BPF program to the raw
tracepoint.
perf lock contention
--------------------
* Add --lock-cgroup option to see contention by cgroups. This should be
used with BPF only (using -b option).
$ sudo perf lock con -ab --lock-cgroup -- sleep 1
contended total wait max wait avg wait cgroup
835 14.06 ms 41.19 us 16.83 us /system.slice/led.service
25 122.38 us 13.77 us 4.89 us /
44 23.73 us 3.87 us 539 ns /user.slice/user-657345.slice/session-c4.scope
1 491 ns 491 ns 491 ns /system.slice/connectd.service
* Add -G/--cgroup-filter option to see contention only for given cgroups.
This can be useful when you identified a cgroup in the above command and
want to investigate more on it. It also works with other output options
like -t/--threads and -l/--lock-addr.
$ sudo perf lock con -ab -G /user.slice/user-657345.slice/session-c4.scope -- sleep 1
contended total wait max wait avg wait type caller
8 77.11 us 17.98 us 9.64 us spinlock futex_wake+0xc8
2 24.56 us 14.66 us 12.28 us spinlock tick_do_update_jiffies64+0x25
1 4.97 us 4.97 us 4.97 us spinlock futex_q_lock+0x2a
* Use per-cpu array for better spinlock tracking. This is to improve
performance of the BPF program and to avoid nested contention on a lock
in the BPF hash map.
* Update callstack check for PowerPC. To find a representative caller of a
lock, it needs to look up the call stacks. It ends the lookup when it sees
0 in the call stack buffer. However, PowerPC call stacks can have 0 values
in the beginning so skip them when it expects valid call stacks after.
perf kwork
----------
* Support 'sched' class (for -k option) so that it can see task scheduling
event (using sched_switch tracepoint) as well as irq and workqueue items.
* Add perf kwork top subcommand to show more accurate cpu utilization with
sched class above. It works both with a recorded data (using perf kwork
record command) and BPF (using -b option). Unlike perf top command, it
does not support interactive mode (yet).
$ sudo perf kwork top -b -k sched
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 160702.425 ms, 8 cpus
%Cpu(s): 36.00% id, 0.00% hi, 0.00% si
%Cpu0 [|||||||||||||||||| 61.66%]
%Cpu1 [|||||||||||||||||| 61.27%]
%Cpu2 [||||||||||||||||||| 66.40%]
%Cpu3 [|||||||||||||||||| 61.28%]
%Cpu4 [|||||||||||||||||| 61.82%]
%Cpu5 [||||||||||||||||||||||| 77.41%]
%Cpu6 [|||||||||||||||||| 61.73%]
%Cpu7 [|||||||||||||||||| 63.25%]
PID SPID %CPU RUNTIME COMMMAND
-------------------------------------------------------------
0 0 38.72 8089.463 ms [swapper/1]
0 0 38.71 8084.547 ms [swapper/3]
0 0 38.33 8007.532 ms [swapper/0]
0 0 38.26 7992.985 ms [swapper/6]
0 0 38.17 7971.865 ms [swapper/4]
0 0 36.74 7447.765 ms [swapper/7]
0 0 33.59 6486.942 ms [swapper/2]
0 0 22.58 3771.268 ms [swapper/5]
9545 9351 2.48 447.136 ms sched-messaging
9574 9351 2.09 418.583 ms sched-messaging
9724 9351 2.05 372.407 ms sched-messaging
9531 9351 2.01 368.804 ms sched-messaging
9512 9351 2.00 362.250 ms sched-messaging
9514 9351 1.95 357.767 ms sched-messaging
9538 9351 1.86 384.476 ms sched-messaging
9712 9351 1.84 386.490 ms sched-messaging
9723 9351 1.83 380.021 ms sched-messaging
9722 9351 1.82 382.738 ms sched-messaging
9517 9351 1.81 354.794 ms sched-messaging
9559 9351 1.79 344.305 ms sched-messaging
9725 9351 1.77 365.315 ms sched-messaging
<SNIP>
* Add hard/soft-irq statistics to perf kwork top. This will show the
total CPU utilization with IRQ stats like below:
$ sudo perf kwork top -b -k sched,irq,softirq
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 12554.889 ms, 8 cpus
%Cpu(s): 96.23% id, 0.10% hi, 0.19% si <---- here
%Cpu0 [| 4.60%]
%Cpu1 [| 4.59%]
%Cpu2 [ 2.73%]
%Cpu3 [| 3.81%]
<SNIP>
perf bench
----------
* Add -G/--cgroups option to perf bench sched pipe. The pipe bench is
good to measure context switch overhead. With this option, it puts
the reader and writer tasks in separate cgroups to enforce context
switch between two different cgroups.
Also it needs to set CPU affinity of the tasks in a CPU to accurately
measure the impact of cgroup context switches.
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.307 [sec]
3.078180 usecs/op
324867 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000':
200,026 context-switches
63 cgroup-switches
0.321637922 seconds time elapsed
You can see small number of cgroup-switches because both write and read
tasks are in the same cgroup.
$ sudo mkdir /sys/fs/cgroup/{AAA,BBB}
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.351 [sec]
3.512990 usecs/op
284657 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB':
200,020 context-switches
200,019 cgroup-switches
0.365034567 seconds time elapsed
Now context-switches and cgroup-switches are almost same. And you can
see the pipe operation took little more.
* Kill child processes when perf bench sched messaging exited abnormally.
Otherwise it'd leave the child doing unnecessary work.
perf test
---------
* Fix various shellcheck issues on the tests written in shell script.
* Skip tests when condition is not satisfied:
- object code reading test for non-text section addresses.
- CoreSight test if cs_etm// event is not available.
- lock contention test if not enough CPUs.
Event parsing
-------------
* Make PMU alias name loading lazy to reduce the startup time in the
event parsing code for perf record, stat and others in the general
case.
* Lazily compute PMU default config. In the same sense, delay PMU
initialization until it's really needed to reduce the startup cost.
* Fix event term values that are raw events. The event specification
can have several terms including event name. But sometimes it clashes
with raw event encoding which starts with 'r' and has hex-digits.
For example, an event named 'read' should be processed as a normal
event but it was mis-treated as a raw encoding and caused a failure.
$ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1
event syntax error: '..nning/event=read/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Event metrics
-------------
* Add "Compat" regex to match event with multiple identifiers.
* Usual updates for Intel, Power10, Arm telemetry/CMN and AmpereOne.
Misc
----
* Assorted memory leak fixes and footprint reduction.
* Add "bpf_skeletons" to perf version --build-options so that users can
check whether their perf tools have BPF support easily.
* Fix unaligned access in Intel-PT packet decoder found by undefined-behavior
sanitizer.
* Avoid frequency mode for the dummy event. Surprisingly it'd impact
kernel timer tick handler performance by force iterating all PMU events.
* Update bash shell completion for events and metrics.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
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Merge tag 'perf-tools-for-v6.7-1-2023-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools
Pull perf tools updates from Namhyung Kim:
"Build:
- Compile BPF programs by default if clang (>= 12.0.1) is available
to enable more features like kernel lock contention, off-cpu
profiling, kwork, sample filtering and so on.
This can be disabled by passing BUILD_BPF_SKEL=0 to make.
- Produce better error messages for bison on debug build (make
DEBUG=1) by defining YYDEBUG symbol internally.
perf record:
- Track sideband events (like FORK/MMAP) from all CPUs even if perf
record targets a subset of CPUs only (using -C option). Otherwise
it may lose some information happened on a CPU out of the target
list.
- Fix checking raw sched_switch tracepoint argument using system BTF.
This affects off-cpu profiling which attaches a BPF program to the
raw tracepoint.
perf lock contention:
- Add --lock-cgroup option to see contention by cgroups. This should
be used with BPF only (using -b option).
$ sudo perf lock con -ab --lock-cgroup -- sleep 1
contended total wait max wait avg wait cgroup
835 14.06 ms 41.19 us 16.83 us /system.slice/led.service
25 122.38 us 13.77 us 4.89 us /
44 23.73 us 3.87 us 539 ns /user.slice/user-657345.slice/session-c4.scope
1 491 ns 491 ns 491 ns /system.slice/connectd.service
- Add -G/--cgroup-filter option to see contention only for given
cgroups.
This can be useful when you identified a cgroup in the above
command and want to investigate more on it. It also works with
other output options like -t/--threads and -l/--lock-addr.
$ sudo perf lock con -ab -G /user.slice/user-657345.slice/session-c4.scope -- sleep 1
contended total wait max wait avg wait type caller
8 77.11 us 17.98 us 9.64 us spinlock futex_wake+0xc8
2 24.56 us 14.66 us 12.28 us spinlock tick_do_update_jiffies64+0x25
1 4.97 us 4.97 us 4.97 us spinlock futex_q_lock+0x2a
- Use per-cpu array for better spinlock tracking. This is to improve
performance of the BPF program and to avoid nested contention on a
lock in the BPF hash map.
- Update callstack check for PowerPC. To find a representative caller
of a lock, it needs to look up the call stacks. It ends the lookup
when it sees 0 in the call stack buffer. However, PowerPC call
stacks can have 0 values in the beginning so skip them when it
expects valid call stacks after.
perf kwork:
- Support 'sched' class (for -k option) so that it can see task
scheduling event (using sched_switch tracepoint) as well as irq and
workqueue items.
- Add perf kwork top subcommand to show more accurate cpu utilization
with sched class above. It works both with a recorded data (using
perf kwork record command) and BPF (using -b option). Unlike perf
top command, it does not support interactive mode (yet).
$ sudo perf kwork top -b -k sched
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 160702.425 ms, 8 cpus
%Cpu(s): 36.00% id, 0.00% hi, 0.00% si
%Cpu0 [|||||||||||||||||| 61.66%]
%Cpu1 [|||||||||||||||||| 61.27%]
%Cpu2 [||||||||||||||||||| 66.40%]
%Cpu3 [|||||||||||||||||| 61.28%]
%Cpu4 [|||||||||||||||||| 61.82%]
%Cpu5 [||||||||||||||||||||||| 77.41%]
%Cpu6 [|||||||||||||||||| 61.73%]
%Cpu7 [|||||||||||||||||| 63.25%]
PID SPID %CPU RUNTIME COMMMAND
-------------------------------------------------------------
0 0 38.72 8089.463 ms [swapper/1]
0 0 38.71 8084.547 ms [swapper/3]
0 0 38.33 8007.532 ms [swapper/0]
0 0 38.26 7992.985 ms [swapper/6]
0 0 38.17 7971.865 ms [swapper/4]
0 0 36.74 7447.765 ms [swapper/7]
0 0 33.59 6486.942 ms [swapper/2]
0 0 22.58 3771.268 ms [swapper/5]
9545 9351 2.48 447.136 ms sched-messaging
9574 9351 2.09 418.583 ms sched-messaging
9724 9351 2.05 372.407 ms sched-messaging
9531 9351 2.01 368.804 ms sched-messaging
9512 9351 2.00 362.250 ms sched-messaging
9514 9351 1.95 357.767 ms sched-messaging
9538 9351 1.86 384.476 ms sched-messaging
9712 9351 1.84 386.490 ms sched-messaging
9723 9351 1.83 380.021 ms sched-messaging
9722 9351 1.82 382.738 ms sched-messaging
9517 9351 1.81 354.794 ms sched-messaging
9559 9351 1.79 344.305 ms sched-messaging
9725 9351 1.77 365.315 ms sched-messaging
<SNIP>
- Add hard/soft-irq statistics to perf kwork top. This will show the
total CPU utilization with IRQ stats like below:
$ sudo perf kwork top -b -k sched,irq,softirq
Starting trace, Hit <Ctrl+C> to stop and report
^C
Total : 12554.889 ms, 8 cpus
%Cpu(s): 96.23% id, 0.10% hi, 0.19% si <---- here
%Cpu0 [| 4.60%]
%Cpu1 [| 4.59%]
%Cpu2 [ 2.73%]
%Cpu3 [| 3.81%]
<SNIP>
perf bench:
- Add -G/--cgroups option to perf bench sched pipe. The pipe bench is
good to measure context switch overhead. With this option, it puts
the reader and writer tasks in separate cgroups to enforce context
switch between two different cgroups.
Also it needs to set CPU affinity of the tasks in a CPU to
accurately measure the impact of cgroup context switches.
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.307 [sec]
3.078180 usecs/op
324867 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000':
200,026 context-switches
63 cgroup-switches
0.321637922 seconds time elapsed
You can see small number of cgroup-switches because both write and
read tasks are in the same cgroup.
$ sudo mkdir /sys/fs/cgroup/{AAA,BBB}
$ sudo perf stat -e context-switches,cgroup-switches -- \
> taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB
# Running 'sched/pipe' benchmark:
# Executed 100000 pipe operations between two processes
Total time: 0.351 [sec]
3.512990 usecs/op
284657 ops/sec
Performance counter stats for 'taskset -c 0 perf bench sched pipe -l 100000 -G AAA,BBB':
200,020 context-switches
200,019 cgroup-switches
0.365034567 seconds time elapsed
Now context-switches and cgroup-switches are almost same. And you
can see the pipe operation took little more.
- Kill child processes when perf bench sched messaging exited
abnormally. Otherwise it'd leave the child doing unnecessary work.
perf test:
- Fix various shellcheck issues on the tests written in shell script.
- Skip tests when condition is not satisfied:
- object code reading test for non-text section addresses.
- CoreSight test if cs_etm// event is not available.
- lock contention test if not enough CPUs.
Event parsing:
- Make PMU alias name loading lazy to reduce the startup time in the
event parsing code for perf record, stat and others in the general
case.
- Lazily compute PMU default config. In the same sense, delay PMU
initialization until it's really needed to reduce the startup cost.
- Fix event term values that are raw events. The event specification
can have several terms including event name. But sometimes it
clashes with raw event encoding which starts with 'r' and has
hex-digits.
For example, an event named 'read' should be processed as a normal
event but it was mis-treated as a raw encoding and caused a
failure.
$ perf stat -e 'uncore_imc_free_running/event=read/' -a sleep 1
event syntax error: '..nning/event=read/'
\___ parser error
Run 'perf list' for a list of valid events
Usage: perf stat [<options>] [<command>]
-e, --event <event> event selector. use 'perf list' to list available events
Event metrics:
- Add "Compat" regex to match event with multiple identifiers.
- Usual updates for Intel, Power10, Arm telemetry/CMN and AmpereOne.
Misc:
- Assorted memory leak fixes and footprint reduction.
- Add "bpf_skeletons" to perf version --build-options so that users
can check whether their perf tools have BPF support easily.
- Fix unaligned access in Intel-PT packet decoder found by
undefined-behavior sanitizer.
- Avoid frequency mode for the dummy event. Surprisingly it'd impact
kernel timer tick handler performance by force iterating all PMU
events.
- Update bash shell completion for events and metrics"
* tag 'perf-tools-for-v6.7-1-2023-11-01' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (187 commits)
perf vendor events intel: Update tsx_cycles_per_elision metrics
perf vendor events intel: Update bonnell version number to v5
perf vendor events intel: Update westmereex events to v4
perf vendor events intel: Update meteorlake events to v1.06
perf vendor events intel: Update knightslanding events to v16
perf vendor events intel: Add typo fix for ivybridge FP
perf vendor events intel: Update a spelling in haswell/haswellx
perf vendor events intel: Update emeraldrapids to v1.01
perf vendor events intel: Update alderlake/alderlake events to v1.23
perf build: Disable BPF skeletons if clang version is < 12.0.1
perf callchain: Fix spelling mistake "statisitcs" -> "statistics"
perf report: Fix spelling mistake "heirachy" -> "hierarchy"
perf python: Fix binding linkage due to rename and move of evsel__increase_rlimit()
perf tests: test_arm_coresight: Simplify source iteration
perf vendor events intel: Add tigerlake two metrics
perf vendor events intel: Add broadwellde two metrics
perf vendor events intel: Fix broadwellde tma_info_system_dram_bw_use metric
perf mem_info: Add and use map_symbol__exit and addr_map_symbol__exit
perf callchain: Minor layout changes to callchain_list
perf callchain: Make brtype_stat in callchain_list optional
...
|
||
|
Ian Rogers
|
78c32f4cb1 |
libperf rc_check: Add RC_CHK_EQUAL
Comparing pointers with reference count checking is tricky to avoid a SEGV. Add a convenience macro to simplify and use. Signed-off-by: Ian Rogers <irogers@google.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: German Gomez <german.gomez@arm.com> Cc: James Clark <james.clark@arm.com> Cc: Nick Terrell <terrelln@fb.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: liuwenyu <liuwenyu7@huawei.com> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Song Liu <song@kernel.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Link: https://lore.kernel.org/r/20231024222353.3024098-5-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org> |
||
|
Ian Rogers
|
75265320d2 |
libperf rc_check: Make implicit enabling work for GCC
Make the implicit REFCOUNT_CHECKING robust to when building with GCC.
Fixes:
|
||
Daniel Borkmann
|
05c31b4ab2 |
libbpf: Add link-based API for netkit
This adds bpf_program__attach_netkit() API to libbpf. Overall it is very
similar to tcx. The API looks as following:
LIBBPF_API struct bpf_link *
bpf_program__attach_netkit(const struct bpf_program *prog, int ifindex,
const struct bpf_netkit_opts *opts);
The struct bpf_netkit_opts is done in similar way as struct bpf_tcx_opts
for supporting bpf_mprog control parameters. The attach location for the
primary and peer device is derived from the program section "netkit/primary"
and "netkit/peer", respectively.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20231024214904.29825-4-daniel@iogearbox.net
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|