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 <[email protected]>
Reported-by: Aishwarya TCV <[email protected]>
Cc: Masami Hiramatsu <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
.../selftests/ftrace/test.d/filter/event-filter-function.tc | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
index 2de7c61d1ae3..3f74c09c56b6 100644
--- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
+++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
@@ -24,7 +24,7 @@ echo 0 > events/enable
echo "Get the most frequently calling function"
sample_events
-target_func=`cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'`
+target_func=`cat trace | grep -o 'call_site=\([^+]*\)' | sed 's/call_site=//' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'`
if [ -z "$target_func" ]; then
exit_fail
fi
--
2.39.2
On Wed, 20 Mar 2024 14:18:44 +0000
Mark Rutland <[email protected]> wrote:
> 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.
>
Looks good to me.
Acked-by: Masami Hiramatsu (Google) <[email protected]>
I think this should be a fix because test task name can have ':'.
Fixes: eb50d0f250e9 ("selftests/ftrace: Choose target function for filter test from samples")
Cc: [email protected]
Shuah, can you pick this as a fix?
Thank you,
> Signed-off-by: Mark Rutland <[email protected]>
> Reported-by: Aishwarya TCV <[email protected]>
> Cc: Masami Hiramatsu <[email protected]>
> Cc: Mathieu Desnoyers <[email protected]>
> Cc: Shuah Khan <[email protected]>
> Cc: Steven Rostedt <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> ---
> .../selftests/ftrace/test.d/filter/event-filter-function.tc | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
> index 2de7c61d1ae3..3f74c09c56b6 100644
> --- a/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
> +++ b/tools/testing/selftests/ftrace/test.d/filter/event-filter-function.tc
> @@ -24,7 +24,7 @@ echo 0 > events/enable
> echo "Get the most frequently calling function"
> sample_events
>
> -target_func=`cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'`
> +target_func=`cat trace | grep -o 'call_site=\([^+]*\)' | sed 's/call_site=//' | sort | uniq -c | sort | tail -n 1 | sed 's/^[ 0-9]*//'`
> if [ -z "$target_func" ]; then
> exit_fail
> fi
> --
> 2.39.2
>
>
--
Masami Hiramatsu (Google) <[email protected]>
On 3/20/24 18:09, Masami Hiramatsu (Google) wrote:
> On Wed, 20 Mar 2024 14:18:44 +0000
> Mark Rutland <[email protected]> wrote:
>
>> 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.
>>
>
> Looks good to me.
>
> Acked-by: Masami Hiramatsu (Google) <[email protected]>
>
> I think this should be a fix because test task name can have ':'.
>
> Fixes: eb50d0f250e9 ("selftests/ftrace: Choose target function for filter test from samples")
> Cc: [email protected]
>
> Shuah, can you pick this as a fix?
>
Applied to linux-ksleftest fixes for next rc
thanks,
-- Shuah