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Athira Rajeev b0979f008f tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

Perf test for perf probe of function from different CU fails
as below:

	./perf test -vv "test perf probe of function from different CU"
	116: test perf probe of function from different CU:
	--- start ---
	test child forked, pid 2679
	Failed to find symbol foo in /tmp/perf-uprobe-different-cu-sh.Msa7iy89bx/testfile
	  Error: Failed to add events.
	--- Cleaning up ---
	"foo" does not hit any event.
	  Error: Failed to delete events.
	---- end(-1) ----
	116: test perf probe of function from different CU                   : FAILED!

The test does below to probe function "foo" :

	# gcc -g -Og -flto -c /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-foo.c
	-o /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-foo.o
	# gcc -g -Og -c /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-main.c
	-o /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-main.o
	# gcc -g -Og -o /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile
	/tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-foo.o
	/tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile-main.o

	# ./perf probe -x /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile foo
	Failed to find symbol foo in /tmp/perf-uprobe-different-cu-sh.XniNxNEVT7/testfile
	   Error: Failed to add events.

Perf probe fails to find symbol foo in the executable placed in
/tmp/perf-uprobe-different-cu-sh.XniNxNEVT7

Simple reproduce:

 # mktemp -d /tmp/perf-checkXXXXXXXXXX
   /tmp/perf-checkcWpuLRQI8j

 # gcc -g -o test test.c
 # cp test /tmp/perf-checkcWpuLRQI8j/
 # nm /tmp/perf-checkcWpuLRQI8j/test | grep foo
   00000000100006bc T foo

 # ./perf probe -x /tmp/perf-checkcWpuLRQI8j/test foo
   Failed to find symbol foo in /tmp/perf-checkcWpuLRQI8j/test
      Error: Failed to add events.

But it works with any files like /tmp/perf/test. Only for
patterns with "/tmp/perf-", this fails.

Further debugging, commit 80d496be89ed ("perf report: Add support
for profiling JIT generated code") added support for profiling JIT
generated code. This patch handles dso's of form
"/tmp/perf-$PID.map" .

The check used "if (strncmp(self->name, "/tmp/perf-", 10) == 0)"
to match "/tmp/perf-$PID.map". With this commit, any dso in
/tmp/perf- folder will be considered separately for processing
(not only JIT created map files ). Fix this by changing the
string pattern to check for "/tmp/perf-%d.map". Add a helper
function is_perf_pid_map_name to do this check. In "struct dso",
dso->long_name holds the long name of the dso file. Since the
/tmp/perf-$PID.map check uses the complete name, use dso___long_name for
the string name.

With the fix,
	# ./perf test "test perf probe of function from different CU"
	117: test perf probe of function from different CU                   : Ok

Fixes: 56cbeacf1435 ("perf probe: Add test for regression introduced by switch to die_get_decl_file()")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Chaitanya S Prakash <chaitanyas.prakash@arm.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: akanksha@linux.ibm.com
Cc: kjain@linux.ibm.com
Cc: maddy@linux.ibm.com
Cc: disgoel@linux.vnet.ibm.com
Cc: linuxppc-dev@lists.ozlabs.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240623064850.83720-1-atrajeev@linux.vnet.ibm.com

2024-06-25 11:00:43 -07:00

accounting

…

arch

perf tools fixes and improvements for v6.10:

2024-05-21 15:45:14 -07:00

bootconfig

…

bpf

bpftool, selftests/hid/bpf: Fix 29 clang warnings

2024-05-06 14:39:36 -07:00

build