Replace deprecated 0-length array in struct bpf_lpm_trie_key with
flexible array. Found with GCC 13:
../kernel/bpf/lpm_trie.c:207:51: warning: array subscript i is outside array bounds of 'const __u8[0]' {aka 'const unsigned char[]'} [-Warray-bounds=]
207 | *(__be16 *)&key->data[i]);
| ^~~~~~~~~~~~~
../include/uapi/linux/swab.h:102:54: note: in definition of macro '__swab16'
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
| ^
../include/linux/byteorder/generic.h:97:21: note: in expansion of macro '__be16_to_cpu'
97 | #define be16_to_cpu __be16_to_cpu
| ^~~~~~~~~~~~~
../kernel/bpf/lpm_trie.c:206:28: note: in expansion of macro 'be16_to_cpu'
206 | u16 diff = be16_to_cpu(*(__be16 *)&node->data[i]
^
| ^~~~~~~~~~~
In file included from ../include/linux/bpf.h:7:
../include/uapi/linux/bpf.h:82:17: note: while referencing 'data'
82 | __u8 data[0]; /* Arbitrary size */
| ^~~~
And found at run-time under CONFIG_FORTIFY_SOURCE:
UBSAN: array-index-out-of-bounds in kernel/bpf/lpm_trie.c:218:49
index 0 is out of range for type '__u8 [*]'
Changing struct bpf_lpm_trie_key is difficult since has been used by
userspace. For example, in Cilium:
struct egress_gw_policy_key {
struct bpf_lpm_trie_key lpm_key;
__u32 saddr;
__u32 daddr;
};
While direct references to the "data" member haven't been found, there
are static initializers what include the final member. For example,
the "{}" here:
struct egress_gw_policy_key in_key = {
.lpm_key = { 32 + 24, {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP & 0Xffffff,
};
To avoid the build time and run time warnings seen with a 0-sized
trailing array for struct bpf_lpm_trie_key, introduce a new struct
that correctly uses a flexible array for the trailing bytes,
struct bpf_lpm_trie_key_u8. As part of this, include the "header"
portion (which is just the "prefixlen" member), so it can be used
by anything building a bpf_lpr_trie_key that has trailing members that
aren't a u8 flexible array (like the self-test[1]), which is named
struct bpf_lpm_trie_key_hdr.
Unfortunately, C++ refuses to parse the __struct_group() helper, so
it is not possible to define struct bpf_lpm_trie_key_hdr directly in
struct bpf_lpm_trie_key_u8, so we must open-code the union directly.
Adjust the kernel code to use struct bpf_lpm_trie_key_u8 through-out,
and for the selftest to use struct bpf_lpm_trie_key_hdr. Add a comment
to the UAPI header directing folks to the two new options.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Closes: https://paste.debian.net/hidden/ca500597/
Link: https://lore.kernel.org/all/202206281009.4332AA33@keescook/ [1]
Link: https://lore.kernel.org/bpf/20240222155612.it.533-kees@kernel.org
Currently old compile rule (CLANG-bpf) doesn't contains VMLINUX_H define
flag which is essential for the bpf program that includes "vmlinux.h".
Also old compile rule doesn't directly specify the compile target as bpf,
instead it uses bunch of extra options with clang followed by long chain
of commands. (e.g. clang | opt | llvm-dis | llc)
In Makefile, there is already new compile rule which is more simple and
neat. And it also has -D__VMLINUX_H__ option. By just changing the _kern
suffix to .bpf will inherit the benefit of the new CLANG-BPF compile
target.
Also, this commit adds dummy gnu/stub.h to the samples/bpf directory.
As commit 1c2dd16add ("selftests/bpf: get rid of -D__x86_64__") noted,
compiling with 'clang -target bpf' will raise an error with stubs.h
unless workaround (-D__x86_64) is used. This commit solves this problem
by adding dummy stub.h to make /usr/include/features.h to follow the
expected path as the same way selftests/bpf dealt with.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20221224071527.2292-4-danieltimlee@gmail.com
We have switched to memcg-based memory accouting and thus the rlimit is
not needed any more. LIBBPF_STRICT_AUTO_RLIMIT_MEMLOCK was introduced in
libbpf for backward compatibility, so we can use it instead now.
This patch also removes the useless header sys/resource.h from many files
in samples/bpf.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20220409125958.92629-2-laoar.shao@gmail.com
Replace deprecated APIs with new ones. Also mute source code using
deprecated AF_XDP (xsk.h). Figuring out what to do with all the AF_XDP
stuff is a separate problem that should be solved with its own set of
changes.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211201232824.3166325-9-andrii@kernel.org
Since bpf is not using rlimit memlock for the memory accounting
and control, do not change the limit in sample applications.
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20201201215900.3569844-35-guro@fb.com
Previously, in order to set the numa_node attribute at the time of map
creation using "libbpf", it was necessary to call bpf_create_map_node()
directly (bpf_load approach), instead of calling bpf_object_load()
that handles everything on its own, including map creation. And because
of this problem, this sample had problems with refactoring from bpf_load
to libbbpf.
However, by commit 1bdb6c9a1c ("libbpf: Add a bunch of attribute
getters/setters for map definitions") added the numa_node attribute and
allowed it to be set in the map.
By using libbpf instead of bpf_load, the inner map definition has
been explicitly declared with BTF-defined format. Also, the element of
ARRAY_OF_MAPS was also statically specified using the BTF format. And
for this reason some logic in fixup_map() was not needed and changed
or removed.
Signed-off-by: Daniel T. Lee <danieltimlee@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200707184855.30968-4-danieltimlee@gmail.com
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of version 2 of the gnu general public license as
published by the free software foundation
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 107 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528171438.615055994@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are two files in the tree called libbpf.h which is becoming
problematic. Most samples don't actually need the local libbpf.h
they simply include it to get to bpf/bpf.h. Include bpf/bpf.h
directly instead.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This patch extends the libbpf to provide API support to
allow specifying BPF object name.
In tools/lib/bpf/libbpf, the C symbol of the function
and the map is used. Regarding section name, all maps are
under the same section named "maps". Hence, section name
is not a good choice for map's name. To be consistent with
map, bpf_prog also follows and uses its function symbol as
the prog's name.
This patch adds logic to collect function's symbols in libbpf.
There is existing codes to collect the map's symbols and no change
is needed.
The bpf_load_program_name() and bpf_map_create_name() are
added to take the name argument. For the other bpf_map_create_xxx()
variants, a name argument is directly added to them.
In samples/bpf, bpf_load.c in particular, the symbol is also
used as the map's name and the map symbols has already been
collected in the existing code. For bpf_prog, bpf_load.c does
not collect the function symbol name. We can consider to collect
them later if there is a need to continue supporting the bpf_load.c.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When cross-compiling the bpf sample map_perf_test for aarch64, I find that
__NR_getpgrp is undefined. This causes build errors. This syscall is deprecated
and requires defining __ARCH_WANT_SYSCALL_DEPRECATED. To avoid having to define
that, just use a different syscall (getppid) for the array map stress test.
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Joel Fernandes <joelaf@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Create a new case to test the LRU lookup performance.
At the beginning, the LRU map is fully loaded (i.e. the number of keys
is equal to map->max_entries). The lookup is done through key 0
to num_map_entries and then repeats from 0 again.
This patch also creates an anonymous struct to properly
name the test params in stress_lru_hmap_alloc() in map_perf_test_kern.c.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes the needed changes to allow each process of
the INNER_LRU_HASH_PREALLOC test to provide its numa node id
when creating the lru map.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Do this change before others start to use this callback.
Change map_perf_test_user.c which seems to be the only user.
This patch extends capabilities of commit 9fd63d05f3 ("bpf:
Allow bpf sample programs (*_user.c) to change bpf_map_def").
Give fixup callback access to struct bpf_map_data, instead of
only stuct bpf_map_def. This add flexibility to allow userspace
to reassign the map file descriptor. This is very useful when
wanting to share maps between several bpf programs.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a map-in-map LRU example.
If we know only a subset of cores will use the
LRU, we can allocate a common LRU list per targeting core
and store it into an array-of-hashs.
It allows using the common LRU map with map-update performance
comparable to the BPF_F_NO_COMMON_LRU map but without wasting memory
on the unused cores that we know they will never access the LRU map.
BPF_F_NO_COMMON_LRU:
> map_perf_test 32 8 10000000 10000000 | awk '{sum += $3}END{print sum}'
9234314 (9.23M/s)
map-in-map LRU:
> map_perf_test 512 8 1260000 80000000 | awk '{sum += $3}END{print sum}'
9962743 (9.96M/s)
Notes that the max_entries for the map-in-map LRU test is 1260000 which
is the max_entries for each inner LRU map. 8 processes have been
started, so 8 * 1260000 = 10080000 (~10M) which is close to what is
used in the BPF_F_NO_COMMON_LRU test.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current bpf_map_def is statically defined during compile
time. This patch allows the *_user.c program to change it during
runtime. It is done by adding load_bpf_file_fixup_map() which
takes a callback. The callback will be called before creating
each map so that it has a chance to modify the bpf_map_def.
The current usecase is to change max_entries in map_perf_test.
It is interesting to test with a much bigger map size in
some cases (e.g. the following patch on bpf_lru_map.c).
However, it is hard to find one size to fit all testing
environment. Hence, it is handy to take the max_entries
as a cmdline arg and then configure the bpf_map_def during
runtime.
This patch adds two cmdline args. One is to configure
the map's max_entries. Another is to configure the max_cnt
which controls how many times a syscall is called.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
One more LRU test will be added later in this patch series.
In this patch, we first move all existing LRU map tests into
a single syscall (connect) first so that the future new
LRU test can be added without hunting another syscall.
One of the map name is also changed from percpu_lru_hash_map
to nocommon_lru_hash_map to avoid the confusion with percpu_hash_map.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
$ map_perf_test 128
speed of HASH bpf_map_lookup_elem() in lookups per second
w/o JIT w/JIT
before 46M 58M
after 42M 74M
perf report
before:
54.23% map_perf_test [kernel.kallsyms] [k] __htab_map_lookup_elem
14.24% map_perf_test [kernel.kallsyms] [k] lookup_elem_raw
8.84% map_perf_test [kernel.kallsyms] [k] htab_map_lookup_elem
5.93% map_perf_test [kernel.kallsyms] [k] bpf_map_lookup_elem
2.30% map_perf_test [kernel.kallsyms] [k] bpf_prog_da4fc6a3f41761a2
1.49% map_perf_test [kernel.kallsyms] [k] kprobe_ftrace_handler
after:
60.03% map_perf_test [kernel.kallsyms] [k] __htab_map_lookup_elem
18.07% map_perf_test [kernel.kallsyms] [k] lookup_elem_raw
2.91% map_perf_test [kernel.kallsyms] [k] bpf_prog_da4fc6a3f41761a2
1.94% map_perf_test [kernel.kallsyms] [k] _einittext
1.90% map_perf_test [kernel.kallsyms] [k] __audit_syscall_exit
1.72% map_perf_test [kernel.kallsyms] [k] kprobe_ftrace_handler
Notice that bpf_map_lookup_elem() and htab_map_lookup_elem() are trivial
functions, yet they take sizeable amount of cpu time.
htab_map_gen_lookup() removes bpf_map_lookup_elem() and converts
htab_map_lookup_elem() into three BPF insns which causing cpu time
for bpf_prog_da4fc6a3f41761a2() slightly increase.
$ map_perf_test 256
speed of ARRAY bpf_map_lookup_elem() in lookups per second
w/o JIT w/JIT
before 97M 174M
after 64M 280M
before:
37.33% map_perf_test [kernel.kallsyms] [k] array_map_lookup_elem
13.95% map_perf_test [kernel.kallsyms] [k] bpf_map_lookup_elem
6.54% map_perf_test [kernel.kallsyms] [k] bpf_prog_da4fc6a3f41761a2
4.57% map_perf_test [kernel.kallsyms] [k] kprobe_ftrace_handler
after:
32.86% map_perf_test [kernel.kallsyms] [k] bpf_prog_da4fc6a3f41761a2
6.54% map_perf_test [kernel.kallsyms] [k] kprobe_ftrace_handler
array_map_gen_lookup() removes calls to array_map_lookup_elem()
and bpf_map_lookup_elem() and replaces them with 7 bpf insns.
The performance without JIT is slower, since executing extra insns
in the interpreter is slower than running native C code,
but with JIT the performance gains are obvious,
since native C->x86 code is replaced with fewer bpf->x86 instructions.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend the map_perf_test_{user,kern}.c infrastructure to stress test
lpm-trie lookups. We hook into the kprobe on sys_gettid() and measure
the latency depending on trie size and lookup count.
On my Intel Haswell i7-6400U, a single gettid() syscall with an empty
bpf program takes roughly 6.5us on my system. Lookups in empty tries
take ~1.8us on first try, ~0.9us on retries. Lookups in tries with 8192
entries take ~7.1us (on the first _and_ any subsequent try).
Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Mack <daniel@zonque.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch has some unit tests and a test_lru_dist.
The test_lru_dist reads in the numeric keys from a file.
The files used here are generated by a modified fio-genzipf tool
originated from the fio test suit. The sample data file can be
found here: https://github.com/iamkafai/bpf-lru
The zipf.* data files have 100k numeric keys and the key is also
ranged from 1 to 100k.
The test_lru_dist outputs the number of unique keys (nr_unique).
F.e. The following means, 61239 of them is unique out of 100k keys.
nr_misses means it cannot be found in the LRU map, so nr_misses
must be >= nr_unique. test_lru_dist also simulates a perfect LRU
map as a comparison:
[root@arch-fb-vm1 ~]# ~/devshare/fb-kernel/linux/samples/bpf/test_lru_dist \
/root/zipf.100k.a1_01.out 4000 1
...
test_parallel_lru_dist (map_type:9 map_flags:0x0):
task:0 BPF LRU: nr_unique:23093(/100000) nr_misses:31603(/100000)
task:0 Perfect LRU: nr_unique:23093(/100000 nr_misses:34328(/100000)
....
test_parallel_lru_dist (map_type:9 map_flags:0x2):
task:0 BPF LRU: nr_unique:23093(/100000) nr_misses:31710(/100000)
task:0 Perfect LRU: nr_unique:23093(/100000 nr_misses:34328(/100000)
[root@arch-fb-vm1 ~]# ~/devshare/fb-kernel/linux/samples/bpf/test_lru_dist \
/root/zipf.100k.a0_01.out 40000 1
...
test_parallel_lru_dist (map_type:9 map_flags:0x0):
task:0 BPF LRU: nr_unique:61239(/100000) nr_misses:67054(/100000)
task:0 Perfect LRU: nr_unique:61239(/100000 nr_misses:66993(/100000)
...
test_parallel_lru_dist (map_type:9 map_flags:0x2):
task:0 BPF LRU: nr_unique:61239(/100000) nr_misses:67068(/100000)
task:0 Perfect LRU: nr_unique:61239(/100000 nr_misses:66993(/100000)
LRU map has also been added to map_perf_test:
/* Global LRU */
[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 16 $i | awk '{r += $3}END{print r " updates"}'; done
1 cpus: 2934082 updates
4 cpus: 7391434 updates
8 cpus: 6500576 updates
/* Percpu LRU */
[root@kerneltest003.31.prn1 ~]# for i in 1 4 8; do echo -n "$i cpus: "; \
./map_perf_test 32 $i | awk '{r += $3}END{print r " updates"}'; done
1 cpus: 2896553 updates
4 cpus: 9766395 updates
8 cpus: 17460553 updates
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Building BPF samples is failing with the below error:
samples/bpf/map_perf_test_user.c: In function ‘main’:
samples/bpf/map_perf_test_user.c:134:9: error: variable ‘r’ has
initializer but incomplete type
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
^
samples/bpf/map_perf_test_user.c:134:21: error: ‘RLIM_INFINITY’
undeclared (first use in this function)
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
^
samples/bpf/map_perf_test_user.c:134:21: note: each undeclared
identifier is reported only once for each function it appears in
samples/bpf/map_perf_test_user.c:134:9: warning: excess elements in
struct initializer [enabled by default]
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
^
samples/bpf/map_perf_test_user.c:134:9: warning: (near initialization
for ‘r’) [enabled by default]
samples/bpf/map_perf_test_user.c:134:9: warning: excess elements in
struct initializer [enabled by default]
samples/bpf/map_perf_test_user.c:134:9: warning: (near initialization
for ‘r’) [enabled by default]
samples/bpf/map_perf_test_user.c:134:16: error: storage size of ‘r’
isn’t known
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
^
samples/bpf/map_perf_test_user.c:139:2: warning: implicit declaration of
function ‘setrlimit’ [-Wimplicit-function-declaration]
setrlimit(RLIMIT_MEMLOCK, &r);
^
samples/bpf/map_perf_test_user.c:139:12: error: ‘RLIMIT_MEMLOCK’
undeclared (first use in this function)
setrlimit(RLIMIT_MEMLOCK, &r);
^
samples/bpf/map_perf_test_user.c:134:16: warning: unused variable ‘r’
[-Wunused-variable]
struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
^
make[2]: *** [samples/bpf/map_perf_test_user.o] Error 1
Fix this by including the necessary header file.
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
performance tests for hash map and per-cpu hash map
with and without pre-allocation
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
