IPv4 has icmp_echo_ignore_broadcast to prevent responding to broadcast pings.
IPv6 needs a similar mechanism.
v1->v2:
- Remove NET_IPV6_ICMP_ECHO_IGNORE_MULTICAST.
Signed-off-by: Stephen Suryaputra <ssuryaextr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
igb sets different WoL settings in system suspend callback and runtime
suspend callback.
The suspend direct complete optimization leaves igb in runtime suspended
state with wrong WoL setting during system suspend.
To fix this, we need to disable suspend direct complete optimization to
let igb always use suspend callback to set correct WoL during system
suspend.
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
According to comments in <linux/netdevice.h> we should return either >0
or -errno from ->ndo_set_features() if changing dev->features by itself.
Return 1 in such places to notify netdev_update_features() about applied
changes in dev->features.
Signed-off-by: Serhey Popovych <serhe.popovych@gmail.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Fix sparse warning:
drivers/net/ethernet/pasemi/pasemi_mac.c:1842:5: warning:
symbol 'pasemi_mac_init_module' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since the request socket is created locally, it'd make more sense to
use reqsk_free() instead of reqsk_put() in TFO and syncookies' error
path.
However, tcp_get_cookie_sock() may set ->rsk_refcnt before freeing the
socket; tcp_conn_request() may also have non-null ->rsk_refcnt because
of tcp_try_fastopen(). In both cases 'req' hasn't been exposed
to the outside world and is safe to free immediately, but that'd
trigger the WARN_ON_ONCE in reqsk_free().
Define __reqsk_free() for these situations where we know nobody's
referencing the socket, even though ->rsk_refcnt might be non-null.
Now we can consolidate the error path of tcp_get_cookie_sock() and
tcp_conn_request().
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix sparse warning:
net/core/datagram.c:411:5: warning:
symbol '__skb_datagram_iter' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix sparse warning:
drivers/net/ethernet/hisilicon/hns3/hns3vf/hclgevf_main.c:407:6:
warning: symbol 'hclgevf_update_link_mode' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix sparse warning:
drivers/net/ethernet/ibm/ibmveth.c:96:21:
warning: symbol 'ibmveth_stats' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP ipv6 fast path dereferences a pointer to get to the inet6
part of a tcp socket, but given the fixed memory placement,
we can do better and avoid a possible cache line miss.
This also reduces register pressure, since we let the compiler
know about this memory placement.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The ibmvnic driver currently reports a fixed value for both speed and
duplex settings regardless of the actual backing device that is being
used. By adding support to the QUERY_PHYS_PARMS command defined by the
PAPR+ we can query the current physical port state and report the proper
values for these feilds.
Reported-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>
Signed-off-by: Murilo Fossa Vicentini <muvic@linux.ibm.com>
Reviewed-by: Mauro S. M. Rodrigues <maurosr@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a dual stack dccp listener accepts an ipv4 flow,
it should not attempt to use an ipv6 header or
inet6_iif() helper.
Fixes: 3df80d9320 ("[DCCP]: Introduce DCCPv6")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When a dual stack tcp listener accepts an ipv4 flow,
it should not attempt to use an ipv6 header or tcp_v6_iif() helper.
Fixes: 1397ed35f2 ("ipv6: add flowinfo for tcp6 pkt_options for all cases")
Fixes: df3687ffc6 ("ipv6: add the IPV6_FL_F_REFLECT flag to IPV6_FL_A_GET")
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, a multicast stream may start out using replicast, because
there are few destinations, and then it should ideally switch to
L2/broadcast IGMP/multicast when the number of destinations grows beyond
a certain limit. The opposite should happen when the number decreases
below the limit.
To eliminate the risk of message reordering caused by method change,
a sending socket must stick to a previously selected method until it
enters an idle period of 5 seconds. Means there is a 5 seconds pause
in the traffic from the sender socket.
If the sender never makes such a pause, the method will never change,
and transmission may become very inefficient as the cluster grows.
With this commit, we allow such a switch between replicast and
broadcast without any need for a traffic pause.
Solution is to send a dummy message with only the header, also with
the SYN bit set, via broadcast or replicast. For the data message,
the SYN bit is set and sending via replicast or broadcast (inverse
method with dummy).
Then, at receiving side any messages follow first SYN bit message
(data or dummy message), they will be held in deferred queue until
another pair (dummy or data message) arrived in other link.
v2: reverse christmas tree declaration
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As a preparation for introducing a smooth switching between replicast
and broadcast method for multicast message, We have to introduce a new
capability flag TIPC_MCAST_RBCTL to handle this new feature.
During a cluster upgrade a node can come back with this new capabilities
which also must be reflected in the cluster capabilities field.
The new feature is only applicable if all node in the cluster supports
this new capability.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, a multicast stream uses either broadcast or replicast as
transmission method, based on the ratio between number of actual
destinations nodes and cluster size.
However, when an L2 interface (e.g., VXLAN) provides pseudo
broadcast support, this becomes very inefficient, as it blindly
replicates multicast packets to all cluster/subnet nodes,
irrespective of whether they host actual target sockets or not.
The TIPC multicast algorithm is able to distinguish real destination
nodes from other nodes, and hence provides a smarter and more
efficient method for transferring multicast messages than
pseudo broadcast can do.
Because of this, we now make it possible for users to force
the broadcast link to permanently switch to using replicast,
irrespective of which capabilities the bearer provides,
or pretend to provide.
Conversely, we also make it possible to force the broadcast link
to always use true broadcast. While maybe less useful in
deployed systems, this may at least be useful for testing the
broadcast algorithm in small clusters.
We retain the current AUTOSELECT ability, i.e., to let the broadcast link
automatically select which algorithm to use, and to switch back and forth
between broadcast and replicast as the ratio between destination
node number and cluster size changes. This remains the default method.
Furthermore, we make it possible to configure the threshold ratio for
such switches. The default ratio is now set to 10%, down from 25% in the
earlier implementation.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In case of kmemdup failure while setting the service name the patch
returns -ENOMEM upstream for processing.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
In netdev_queue_add_kobject and rx_queue_add_kobject,
if sysfs_create_group failed, kobject_put will call
netdev_queue_release to decrease dev refcont, however
dev_hold has not be called. So we will see this while
unregistering dev:
unregister_netdevice: waiting for bcsh0 to become free. Usage count = -1
Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: d0d6683716 ("net: don't decrement kobj reference count on init failure")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When using 16K DMA buffers and ring mode, the DES3 refill is not working
correctly as the function is using a bogus pointer for checking the
private data. As a result stale pointers will remain in the RX descriptor
ring, so DMA will now likely overwrite/corrupt some already freed memory.
As simple reproducer, just receive some UDP traffic:
# ifconfig eth0 down; ifconfig eth0 mtu 9000; ifconfig eth0 up
# iperf3 -c 192.168.253.40 -u -b 0 -R
If you didn't crash by now check the RX descriptors to find non-contiguous
RX buffers:
cat /sys/kernel/debug/stmmaceth/eth0/descriptors_status
[...]
1 [0x2be5020]: 0xa3220321 0x9ffc1ffc 0x72d70082 0x130e207e
^^^^^^^^^^^^^^^^^^^^^
2 [0x2be5040]: 0xa3220321 0x9ffc1ffc 0x72998082 0x1311a07e
^^^^^^^^^^^^^^^^^^^^^
A simple ping test will now report bad data:
# ping -s 8200 192.168.253.40
PING 192.168.253.40 (192.168.253.40) 8200(8228) bytes of data.
8208 bytes from 192.168.253.40: icmp_seq=1 ttl=64 time=1.00 ms
wrong data byte #8144 should be 0xd0 but was 0x88
Fix the wrong pointer. Also we must refill DES3 only if the DMA buffer
size is 16K.
Fixes: 54139cf3bb ("net: stmmac: adding multiple buffers for rx")
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Acked-by: Jose Abreu <joabreu@synopsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A recently added function in mlxsw triggers a harmless compiler warning:
In file included from drivers/net/ethernet/mellanox/mlxsw/core.h:17,
from drivers/net/ethernet/mellanox/mlxsw/core_env.c:7:
drivers/net/ethernet/mellanox/mlxsw/core_env.c: In function 'mlxsw_env_module_temp_thresholds_get':
drivers/net/ethernet/mellanox/mlxsw/reg.h:8015:45: error: '*' in boolean context, suggest '&&' instead [-Werror=int-in-bool-context]
#define MLXSW_REG_MTMP_TEMP_TO_MC(val) (val * 125)
~~~~~^~~~~~
drivers/net/ethernet/mellanox/mlxsw/core_env.c:116:8: note: in expansion of macro 'MLXSW_REG_MTMP_TEMP_TO_MC'
if (!MLXSW_REG_MTMP_TEMP_TO_MC(module_temp)) {
^~~~~~~~~~~~~~~~~~~~~~~~~
The warning is normally disabled, but it would be nice to enable
it to find real bugs, and there are no other known instances at
the moment.
Replace the negation with a zero-comparison, which also matches
the comment above it.
Fixes: d93c19a1d9 ("mlxsw: core: Add API for QSFP module temperature thresholds reading")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds processing of PERF_BPF_EVENT_PROG_LOAD, which sets
proper DSO type/id/etc of memory regions mapped to BPF programs to
DSO_BINARY_TYPE__BPF_PROG_INFO.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-14-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Introduce a new dso type DSO_BINARY_TYPE__BPF_PROG_INFO for BPF programs. In
symbol__disassemble(), DSO_BINARY_TYPE__BPF_PROG_INFO dso will call into a new
function symbol__disassemble_bpf() in an upcoming patch, where annotation line
information is filled based bpf_prog_info and btf saved in given perf_env.
Committer notes:
Removed the unnamed union with 'bpf_prog' and 'cache' in 'struct dso',
to fix this bug when exiting 'perf top':
# perf top
perf: Segmentation fault
-------- backtrace --------
perf[0x5a785a]
/lib64/libc.so.6(+0x385bf)[0x7fd68443c5bf]
perf(rb_first+0x2b)[0x4d6eeb]
perf(dso__delete+0xb7)[0x4dffb7]
perf[0x4f9e37]
perf(perf_session__delete+0x64)[0x504df4]
perf(cmd_top+0x1957)[0x454467]
perf[0x4aad18]
perf(main+0x61c)[0x42ec7c]
/lib64/libc.so.6(__libc_start_main+0xf2)[0x7fd684428412]
perf(_start+0x2d)[0x42eead]
#
# addr2line -fe ~/bin/perf 0x4dffb7
dso_cache__free
/home/acme/git/perf/tools/perf/util/dso.c:713
That is trying to access the dso->data.cache, and that is not used with
BPF programs, so we end up accessing what is in bpf_prog.first_member,
b00m.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-13-songliubraving@fb.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Both libbfd and libopcodes are distributed with binutil-dev/devel. When
libbfd is present, it is OK to assume that libopcodes also present. This
has been a safe assumption for bpftool.
This patch adds -lopcodes to perf/Makefile.config. libopcodes will be
used in the next commit for BPF annotation.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-12-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch enables 'perf record' to save BTF information as headers to
perf.data.
A new header type HEADER_BPF_BTF is introduced for this data.
Committer testing:
As root, being on the kernel sources top level directory, run:
# perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c -e *msg
Just to compile and load a BPF program that attaches to the
raw_syscalls:sys_{enter,exit} tracepoints to trace the syscalls ending
in "msg" (recvmsg, sendmsg, recvmmsg, sendmmsg, etc).
Make sure you have a recent enough clang, say version 9, to get the
BTF ELF sections needed for this testing:
# clang --version | head -1
clang version 9.0.0 (https://git.llvm.org/git/clang.git/ 7906282d3afec5dfdc2b27943fd6c0309086c507) (https://git.llvm.org/git/llvm.git/ a1b5de1ff8ae8bc79dc8e86e1f82565229bd0500)
# readelf -SW tools/perf/examples/bpf/augmented_raw_syscalls.o | grep BTF
[22] .BTF PROGBITS 0000000000000000 000ede 000b0e 00 0 0 1
[23] .BTF.ext PROGBITS 0000000000000000 0019ec 0002a0 00 0 0 1
[24] .rel.BTF.ext REL 0000000000000000 002fa8 000270 10 30 23 8
Then do a systemwide perf record session for a few seconds:
# perf record -a sleep 2s
Then look at:
# perf report --header-only | grep b[pt]f
# event : name = cycles:ppp, , id = { 1116204, 1116205, 1116206, 1116207, 1116208, 1116209, 1116210, 1116211 }, size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|PERIOD, read_format = ID, disabled = 1, inherit = 1, mmap = 1, comm = 1, freq = 1, enable_on_exec = 1, task = 1, precise_ip = 3, sample_id_all = 1, exclude_guest = 1, mmap2 = 1, comm_exec = 1, ksymbol = 1, bpf_event = 1
# bpf_prog_info of id 13
# bpf_prog_info of id 14
# bpf_prog_info of id 15
# bpf_prog_info of id 16
# bpf_prog_info of id 17
# bpf_prog_info of id 18
# bpf_prog_info of id 21
# bpf_prog_info of id 22
# bpf_prog_info of id 51
# bpf_prog_info of id 52
# btf info of id 8
#
We need to show more info about these BPF and BTF entries , but that can
be done later.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-10-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
BTF contains information necessary to annotate BPF programs. This patch
saves BTF for BPF programs loaded in the system.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-9-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch enables perf-record to save bpf_prog_info information as
headers to perf.data. A new header type HEADER_BPF_PROG_INFO is
introduced for this data.
Committer testing:
As root, being on the kernel sources top level directory, run:
# perf trace -e tools/perf/examples/bpf/augmented_raw_syscalls.c -e *msg
Just to compile and load a BPF program that attaches to the
raw_syscalls:sys_{enter,exit} tracepoints to trace the syscalls ending
in "msg" (recvmsg, sendmsg, recvmmsg, sendmmsg, etc).
Then do a systemwide perf record session for a few seconds:
# perf record -a sleep 2s
Then look at:
# perf report --header-only | grep -i bpf
# bpf_prog_info of id 13
# bpf_prog_info of id 14
# bpf_prog_info of id 15
# bpf_prog_info of id 16
# bpf_prog_info of id 17
# bpf_prog_info of id 18
# bpf_prog_info of id 21
# bpf_prog_info of id 22
# bpf_prog_info of id 208
# bpf_prog_info of id 209
#
We need to show more info about these programs, like bpftool does for
the ones running on the system, i.e. 'perf record/perf report' become a
way of saving the BPF state in a machine to then analyse on another,
together with all the other information that is already saved in the
perf.data header:
# perf report --header-only
# ========
# captured on : Tue Mar 12 11:42:13 2019
# header version : 1
# data offset : 296
# data size : 16294184
# feat offset : 16294480
# hostname : quaco
# os release : 5.0.0+
# perf version : 5.0.gd783c8
# arch : x86_64
# nrcpus online : 8
# nrcpus avail : 8
# cpudesc : Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
# cpuid : GenuineIntel,6,142,10
# total memory : 24555720 kB
# cmdline : /home/acme/bin/perf (deleted) record -a
# event : name = cycles:ppp, , id = { 3190123, 3190124, 3190125, 3190126, 3190127, 3190128, 3190129, 3190130 }, size = 112, { sample_period, sample_freq } = 4000, sample_type = IP|TID|TIME|CPU|PERIOD, read_format = ID, disabled = 1, inherit = 1, mmap = 1, comm = 1, freq = 1, task = 1, precise_ip = 3, sample_id_all = 1, exclude_guest = 1, mmap2 = 1, comm_exec = 1
# CPU_TOPOLOGY info available, use -I to display
# NUMA_TOPOLOGY info available, use -I to display
# pmu mappings: intel_pt = 8, software = 1, power = 11, uprobe = 7, uncore_imc = 12, cpu = 4, cstate_core = 18, uncore_cbox_2 = 15, breakpoint = 5, uncore_cbox_0 = 13, tracepoint = 2, cstate_pkg = 19, uncore_arb = 17, kprobe = 6, i915 = 10, msr = 9, uncore_cbox_3 = 16, uncore_cbox_1 = 14
# CACHE info available, use -I to display
# time of first sample : 116392.441701
# time of last sample : 116400.932584
# sample duration : 8490.883 ms
# MEM_TOPOLOGY info available, use -I to display
# bpf_prog_info of id 13
# bpf_prog_info of id 14
# bpf_prog_info of id 15
# bpf_prog_info of id 16
# bpf_prog_info of id 17
# bpf_prog_info of id 18
# bpf_prog_info of id 21
# bpf_prog_info of id 22
# bpf_prog_info of id 208
# bpf_prog_info of id 209
# missing features: TRACING_DATA BRANCH_STACK GROUP_DESC AUXTRACE STAT CLOCKID DIR_FORMAT
# ========
#
Committer notes:
We can't use the libbpf unconditionally, as the build may have been with
NO_LIBBPF, when we end up with linking errors, so provide dummy
{process,write}_bpf_prog_info() wrapped by HAVE_LIBBPF_SUPPORT for that
case.
Printing are not affected by this, so can continue as is.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-8-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
bpf_prog_info contains information necessary to annotate bpf programs.
This patch saves bpf_prog_info for bpf programs loaded in the system.
Some big picture of the next few patches:
To fully annotate BPF programs with source code mapping, 4 different
informations are needed:
1) PERF_RECORD_KSYMBOL
2) PERF_RECORD_BPF_EVENT
3) bpf_prog_info
4) btf
Before this set, 1) and 2) in the list are already saved to perf.data
file. For BPF programs that are already loaded before perf run, 1) and 2)
are synthesized by perf_event__synthesize_bpf_events(). For short living
BPF programs, 1) and 2) are generated by kernel.
This set handles 3) and 4) from the list. Again, it is necessary to handle
existing BPF program and short living program separately.
This patch handles 3) for exising BPF programs while synthesizing 1) and
2) in perf_event__synthesize_bpf_events(). These data are stored in
perf_env. The next patch saves these data from perf_env to perf.data as
headers.
Similarly, the two patches after the next saves 4) of existing BPF
programs to perf_env and perf.data.
Another patch later will handle 3) and 4) for short living BPF programs
by monitoring 1) and 2) in a dedicate thread.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-7-songliubraving@fb.com
[ set env->bpf_progs.infos_cnt to zero in perf_env__purge_bpf() as noted by jolsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This patch changes the arguments of perf_event__synthesize_bpf_events()
to include perf_session* instead of perf_tool*. perf_session will be
used in the next patch.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: kernel-team@fb.com
Link: http://lkml.kernel.org/r/20190312053051.2690567-6-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
With bpf_program__get_prog_info_linear, we can simplify the logic that
synthesizes bpf events.
This patch doesn't change the behavior of the code.
Commiter notes:
Needed this (for all four variables), suggested by Song, to overcome
build failure on debian experimental cross building to MIPS 32-bit:
- u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(info->prog_tags);
+ u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(uintptr_t)(info->prog_tags);
util/bpf-event.c: In function 'perf_event__synthesize_one_bpf_prog':
util/bpf-event.c:143:35: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
u8 (*prog_tags)[BPF_TAG_SIZE] = (void *)(info->prog_tags);
^
util/bpf-event.c:144:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
__u32 *prog_lens = (__u32 *)(info->jited_func_lens);
^
util/bpf-event.c:145:23: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
__u64 *prog_addrs = (__u64 *)(info->jited_ksyms);
^
util/bpf-event.c:146:22: error: cast to pointer from integer of different size [-Werror=int-to-pointer-cast]
void *func_infos = (void *)(info->func_info);
^
cc1: all warnings being treated as errors
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-5-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently, bpf_prog_info includes 9 arrays. The user has the option to
fetch any combination of these arrays. However, this requires a lot of
handling.
This work becomes more tricky when we need to store bpf_prog_info to a
file, because these arrays are allocated independently.
This patch introduces 'struct bpf_prog_info_linear', which stores arrays
of bpf_prog_info in continuous memory.
Helper functions are introduced to unify the work to get different sets
of bpf_prog_info. Specifically, bpf_program__get_prog_info_linear()
allows the user to select which arrays to fetch, and handles details for
the user.
Please see the comments right before 'enum bpf_prog_info_array' for more
details and examples.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lkml.kernel.org/r/ce92c091-e80d-a0c1-4aa0-987706c42b20@iogearbox.net
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: kernel-team@fb.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-3-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently, monitoring of BPF programs through bpf_event is off by
default for 'perf record'.
To turn it on, the user need to use option "--bpf-event". As BPF gets
wider adoption in different subsystems, this option becomes
inconvenient.
This patch makes bpf_event on by default, and adds option "--no-bpf-event"
to turn it off. Since option --bpf-event is not released yet, it is safe
to remove it.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: kernel-team@fb.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stanislav Fomichev <sdf@google.com>
Link: http://lkml.kernel.org/r/20190312053051.2690567-2-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
=================================================================
==20875==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 1160 byte(s) in 1 object(s) allocated from:
#0 0x7f1b6fc84138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
#1 0x55bd50005599 in zalloc util/util.h:23
#2 0x55bd500068f5 in perf_evsel__newtp_idx util/evsel.c:327
#3 0x55bd4ff810fc in perf_evsel__newtp /home/work/linux/tools/perf/util/evsel.h:216
#4 0x55bd4ff81608 in test__perf_evsel__tp_sched_test tests/evsel-tp-sched.c:69
#5 0x55bd4ff528e6 in run_test tests/builtin-test.c:358
#6 0x55bd4ff52baf in test_and_print tests/builtin-test.c:388
#7 0x55bd4ff543fe in __cmd_test tests/builtin-test.c:583
#8 0x55bd4ff5572f in cmd_test tests/builtin-test.c:722
#9 0x55bd4ffc4087 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
#10 0x55bd4ffc45c6 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
#11 0x55bd4ffc49ca in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
#12 0x55bd4ffc5138 in main /home/changbin/work/linux/tools/perf/perf.c:520
#13 0x7f1b6e34809a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
Indirect leak of 19 byte(s) in 1 object(s) allocated from:
#0 0x7f1b6fc83f30 in __interceptor_malloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xedf30)
#1 0x7f1b6e3ac30f in vasprintf (/lib/x86_64-linux-gnu/libc.so.6+0x8830f)
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 6a6cd11d4e ("perf test: Add test for the sched tracepoint format fields")
Link: http://lkml.kernel.org/r/20190316080556.3075-17-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Using gcc's ASan, Changbin reports:
=================================================================
==7494==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 48 byte(s) in 1 object(s) allocated from:
#0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
#1 0x5625e5330a5e in zalloc util/util.h:23
#2 0x5625e5330a9b in perf_counts__new util/counts.c:10
#3 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
#4 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
#5 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
#6 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
#7 0x5625e51528e6 in run_test tests/builtin-test.c:358
#8 0x5625e5152baf in test_and_print tests/builtin-test.c:388
#9 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
#10 0x5625e515572f in cmd_test tests/builtin-test.c:722
#11 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
#12 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
#13 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
#14 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
#15 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
Indirect leak of 72 byte(s) in 1 object(s) allocated from:
#0 0x7f0333a89138 in calloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee138)
#1 0x5625e532560d in zalloc util/util.h:23
#2 0x5625e532566b in xyarray__new util/xyarray.c:10
#3 0x5625e5330aba in perf_counts__new util/counts.c:15
#4 0x5625e5330ca0 in perf_evsel__alloc_counts util/counts.c:47
#5 0x5625e520d8e5 in __perf_evsel__read_on_cpu util/evsel.c:1505
#6 0x5625e517a985 in perf_evsel__read_on_cpu /home/work/linux/tools/perf/util/evsel.h:347
#7 0x5625e517ad1a in test__openat_syscall_event tests/openat-syscall.c:47
#8 0x5625e51528e6 in run_test tests/builtin-test.c:358
#9 0x5625e5152baf in test_and_print tests/builtin-test.c:388
#10 0x5625e51543fe in __cmd_test tests/builtin-test.c:583
#11 0x5625e515572f in cmd_test tests/builtin-test.c:722
#12 0x5625e51c3fb8 in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
#13 0x5625e51c44f7 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
#14 0x5625e51c48fb in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
#15 0x5625e51c5069 in main /home/changbin/work/linux/tools/perf/perf.c:520
#16 0x7f033214d09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
His patch took care of evsel->prev_raw_counts, but the above backtraces
are about evsel->counts, so fix that instead.
Reported-by: Changbin Du <changbin.du@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/n/tip-hd1x13g59f0nuhe4anxhsmfp@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add function __maps__purge_names() to purge all maps from the names
tree. We need to cleanup the names tree in maps__exit().
Detected with gcc's ASan.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 1e6285699b ("perf symbols: Fix slowness due to -ffunction-section")
Link: http://lkml.kernel.org/r/20190316080556.3075-12-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
There are two trees for each map inserted by maps__insert(), so remove
it from the 'names' tree in __maps__remove().
Detected with gcc's ASan.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Eric Saint-Etienne <eric.saint.etienne@oracle.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 1e6285699b ("perf symbols: Fix slowness due to -ffunction-section")
Link: http://lkml.kernel.org/r/20190316080556.3075-11-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We need to map__put() before returning from failure of
sample__resolve_callchain().
Detected with gcc's ASan.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Krister Johansen <kjlx@templeofstupid.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 9c68ae98c6 ("perf callchain: Reference count maps")
Link: http://lkml.kernel.org/r/20190316080556.3075-10-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
We should go to the cleanup path, to avoid leaks, detected using gcc's
ASan.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190316080556.3075-9-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Detected with gcc's ASan:
Direct leak of 4356 byte(s) in 120 object(s) allocated from:
#0 0x7ff1a2b5a070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
#1 0x55719aef4814 in build_id_cache__origname util/build-id.c:215
#2 0x55719af649b6 in print_sdt_events util/parse-events.c:2339
#3 0x55719af66272 in print_events util/parse-events.c:2542
#4 0x55719ad1ecaa in cmd_list /home/changbin/work/linux/tools/perf/builtin-list.c:58
#5 0x55719aec745d in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
#6 0x55719aec7d1a in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
#7 0x55719aec8184 in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
#8 0x55719aeca41a in main /home/changbin/work/linux/tools/perf/perf.c:520
#9 0x7ff1a07ae09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 40218daea1 ("perf list: Show SDT and pre-cached events")
Link: http://lkml.kernel.org/r/20190316080556.3075-7-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Detected with gcc's ASan:
Direct leak of 66 byte(s) in 5 object(s) allocated from:
#0 0x7ff3b1f32070 in __interceptor_strdup (/usr/lib/x86_64-linux-gnu/libasan.so.5+0x3b070)
#1 0x560c8761034d in collect_config util/config.c:597
#2 0x560c8760d9cb in get_value util/config.c:169
#3 0x560c8760dfd7 in perf_parse_file util/config.c:285
#4 0x560c8760e0d2 in perf_config_from_file util/config.c:476
#5 0x560c876108fd in perf_config_set__init util/config.c:661
#6 0x560c87610c72 in perf_config_set__new util/config.c:709
#7 0x560c87610d2f in perf_config__init util/config.c:718
#8 0x560c87610e5d in perf_config util/config.c:730
#9 0x560c875ddea0 in main /home/changbin/work/linux/tools/perf/perf.c:442
#10 0x7ff3afb8609a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Fixes: 20105ca124 ("perf config: Introduce perf_config_set class")
Link: http://lkml.kernel.org/r/20190316080556.3075-6-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The option 'sort-order' should be 'sort_order'.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Milian Wolff <milian.wolff@kdab.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 893c5c798b ("perf config: Show default report configuration in example and docs")
Link: http://lkml.kernel.org/r/20190316080556.3075-5-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Optimization level '-Og' offers a reasonable level of optimization while
maintaining fast compilation and a good debugging experience. This patch
tries to make it work.
$ make DEBUG=1 EXTRA_CFLAGS='-Og'
bench/epoll-ctl.c: In function ‘do_threads’:
bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
return ret;
^~~
...
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Detected via gcc's ASan:
Direct leak of 2048 byte(s) in 64 object(s) allocated from:
6 #0 0x7f606512e370 in __interceptor_realloc (/usr/lib/x86_64-linux-gnu/libasan.so.5+0xee370)
7 #1 0x556b0f1d7ddd in thread_map__realloc util/thread_map.c:43
8 #2 0x556b0f1d84c7 in thread_map__new_by_tid util/thread_map.c:85
9 #3 0x556b0f0e045e in is_event_supported util/parse-events.c:2250
10 #4 0x556b0f0e1aa1 in print_hwcache_events util/parse-events.c:2382
11 #5 0x556b0f0e3231 in print_events util/parse-events.c:2514
12 #6 0x556b0ee0a66e in cmd_list /home/changbin/work/linux/tools/perf/builtin-list.c:58
13 #7 0x556b0f01e0ae in run_builtin /home/changbin/work/linux/tools/perf/perf.c:302
14 #8 0x556b0f01e859 in handle_internal_command /home/changbin/work/linux/tools/perf/perf.c:354
15 #9 0x556b0f01edc8 in run_argv /home/changbin/work/linux/tools/perf/perf.c:398
16 #10 0x556b0f01f71f in main /home/changbin/work/linux/tools/perf/perf.c:520
17 #11 0x7f6062ccf09a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fixes: 89896051f8 ("perf tools: Do not put a variable sized type not at the end of a struct")
Link: http://lkml.kernel.org/r/20190316080556.3075-3-changbin.du@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
AddressSanitizer (or ASan) and UndefinedBehaviorSanitizer (or UBSan) are
very useful tools to detect program bugs:
- AddressSanitizer (or ASan) is a GCC feature that detects memory
corruption bugs such as buffer overflows and memory leaks.
- UndefinedBehaviorSanitizer (or UBSan) is a fast undefined behavior
detector supported by GCC. UBSan detects undefined behaviors of programs
at runtime.
This patch adds a document about how to use them on perf. Later patches will fix
some of the issues disclosed by them.
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Reviewed-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190316080556.3075-2-changbin.du@gmail.com
[ Make some changes based on comments made by Jiri Olsa ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
