linux/tools
Mark Rutland 8ecab2e645 selftests/ftrace: Fix event filter target_func selection
The event filter function test has been failing in our internal test
farm:

| # not ok 33 event filter function - test event filtering on functions

Running the test in verbose mode indicates that this is because the test
erroneously determines that kmem_cache_free() is the most common caller
of kmem_cache_free():

  # # + cut -d: -f3 trace
  # # + sed s/call_site=([^+]*)+0x.*/1/
  # # + sort
  # # + uniq -c
  # # + sort
  # # + tail -n 1
  # # + sed s/^[ 0-9]*//
  # # + target_func=kmem_cache_free

... and as kmem_cache_free() doesn't call itself, setting this as the
filter function for kmem_cache_free() results in no hits, and
consequently the test fails:

  # # + grep kmem_cache_free trace
  # # + grep kmem_cache_free
  # # + wc -l
  # # + hitcnt=0
  # # + grep kmem_cache_free trace
  # # + grep -v kmem_cache_free
  # # + wc -l
  # # + misscnt=0
  # # + [ 0 -eq 0 ]
  # # + exit_fail

This seems to be because the system in question has tasks with ':' in
their name (which a number of kernel worker threads have). These show up
in the trace, e.g.

  test:.sh-1299    [004] .....  2886.040608: kmem_cache_free: call_site=putname+0xa4/0xc8 ptr=000000000f4d22f4 name=names_cache

... and so when we try to extact the call_site with:

  cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/'

... the 'cut' command will extrace the column containing
'kmem_cache_free' rather than the column containing 'call_site=...', and
the 'sed' command will leave this unchanged. Consequently, the test will
decide to use 'kmem_cache_free' as the filter function, resulting in the
failure seen above.

Fix this by matching the 'call_site=<func>' part specifically to extract
the function name.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Aishwarya TCV <aishwarya.tcv@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
2024-03-29 13:57:14 -06:00
..
accounting
arch LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
bootconfig
bpf libbpf: Recognize __arena global variables. 2024-03-11 15:43:35 -07:00
build perf: build: introduce the libcapstone 2024-02-20 18:06:25 -08:00
certs
cgroup
counter
crypto crypto: ccp - Update return values for some unit tests 2024-02-24 08:41:20 +08:00
debugging
firewire
firmware
gpio
hv
iio tools: iio: replace seekdir() in iio_generic_buffer 2024-01-23 22:06:56 +00:00
include LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
kvm/kvm_stat
laptop
leds
lib Kbuild updates for v6.9 2024-03-21 14:41:00 -07:00
memory-model
mm tools/mm: add thpmaps script to dump THP usage info 2024-02-22 10:24:38 -08:00
net/ynl tools: ynl: add header guards for nlctrl 2024-03-19 11:33:02 +01:00
objtool LoongArch changes for v6.9 2024-03-22 10:22:45 -07:00
pci
pcmcia
perf RISC-V Patches for the 6.9 Merge Window 2024-03-22 10:41:13 -07:00
power linux-cpupower-6.9-rc1 2024-03-07 21:02:51 +01:00
rcu
scripts treewide: remove meaningless assignments in Makefiles 2024-02-23 14:19:07 -08:00
spi
testing selftests/ftrace: Fix event filter target_func selection 2024-03-29 13:57:14 -06:00
thermal tools/thermal/tmon: Fix compilation warning for wrong format 2024-01-02 09:33:19 +01:00
time
tracing tools/rtla: Add -U/--user-load option to timerlat 2024-03-20 05:39:06 +01:00
usb
verification tools/verification: Use tools/build makefiles on rv 2024-03-20 05:39:06 +01:00
virtio tools: virtio: introduce vhost_net_test 2024-03-05 11:38:14 +01:00
wmi
workqueue workqueue: Implement BH workqueues to eventually replace tasklets 2024-02-04 11:28:06 -10:00
Makefile