[PATCH V3 1/3] tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

[PATCH V3 1/3] tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

[Athira Rajeev]

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.

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

Signed-off-by: Athira Rajeev<atrajeev@linux.vnet.ibm.com>
---
Changelog:
v2 -> v3:
Addressed review comment from Adrian and James.
Added perf_pid_map_tid to save the tid and modified
is_perf_pid_map_name to use this internally.

v1 -> v2:
Addressed review comments from Adrian.
Added helper function is_perf_pid_map_name to check
dso name of form "/tmp/perf-%d.map". Used sscanf
instead of regex comparison.

 tools/perf/util/dso.c    | 12 ++++++++++++
 tools/perf/util/dso.h    |  4 ++++
 tools/perf/util/symbol.c |  3 ++-
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
index dde706b71da7..2340c4f6d0c2 100644
--- a/tools/perf/util/dso.c
+++ b/tools/perf/util/dso.c
@@ -1652,3 +1652,15 @@ int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
 	scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
 	return 0;
 }
+
+bool perf_pid_map_tid(const char *dso_name, int *tid)
+{
+	return sscanf(dso_name, "/tmp/perf-%d.map", tid) == 1;
+}
+
+bool is_perf_pid_map_name(const char *dso_name)
+{
+	int tid;
+
+	return perf_pid_map_tid(dso_name, &tid);
+}
diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
index df2c98402af3..d72f3b8c37f6 100644
--- a/tools/perf/util/dso.h
+++ b/tools/perf/util/dso.h
@@ -809,4 +809,8 @@ void reset_fd_limit(void);
 u64 dso__find_global_type(struct dso *dso, u64 addr);
 u64 dso__findnew_global_type(struct dso *dso, u64 addr, u64 offset);
 
+/* Check if dso name is of format "/tmp/perf-%d.map" */
+bool perf_pid_map_tid(const char *dso_name, int *tid);
+bool is_perf_pid_map_name(const char *dso_name);
+
 #endif /* __PERF_DSO */
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 9e5940b5bc59..aee0a4cfb383 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1799,7 +1799,8 @@ int dso__load(struct dso *dso, struct map *map)
 	const char *map_path = dso__long_name(dso);
 
 	mutex_lock(dso__lock(dso));
-	perfmap = strncmp(dso__name(dso), "/tmp/perf-", 10) == 0;
+	perfmap = is_perf_pid_map_name(map_path);
+
 	if (perfmap) {
 		if (dso__nsinfo(dso) &&
 		    (dso__find_perf_map(newmapname, sizeof(newmapname),
-- 
2.35.3

[PATCH V3 2/3] tools/perf: Use is_perf_pid_map_name helper function to check dso's of pattern /tmp/perf-%d.map

[Athira Rajeev]

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".

Some of the references doesn't check exactly for same pattern.
some uses "if (!strncmp(dso_name, "/tmp/perf-", 10))". Fix
this by using helper function perf_pid_map_tid and
is_perf_pid_map_name which looks for proper pattern of
form: "/tmp/perf-$PID.map" for these checks.

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
---
 tools/perf/util/dsos.c    | 2 +-
 tools/perf/util/srcline.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/dsos.c b/tools/perf/util/dsos.c
index ab3d0c01dd63..846828ea1f00 100644
--- a/tools/perf/util/dsos.c
+++ b/tools/perf/util/dsos.c
@@ -275,7 +275,7 @@ static void dso__set_basename(struct dso *dso)
 	char *base, *lname;
 	int tid;
 
-	if (sscanf(dso__long_name(dso), "/tmp/perf-%d.map", &tid) == 1) {
+	if (perf_pid_map_tid(dso__long_name(dso), &tid)) {
 		if (asprintf(&base, "[JIT] tid %d", tid) < 0)
 			return;
 	} else {
diff --git a/tools/perf/util/srcline.c b/tools/perf/util/srcline.c
index 9d670d8c1c08..51eb78993fe2 100644
--- a/tools/perf/util/srcline.c
+++ b/tools/perf/util/srcline.c
@@ -39,7 +39,7 @@ static const char *srcline_dso_name(struct dso *dso)
 	if (dso_name[0] == '[')
 		return NULL;
 
-	if (!strncmp(dso_name, "/tmp/perf-", 10))
+	if (is_perf_pid_map_name(dso_name))
 		return NULL;
 
 	return dso_name;
-- 
2.35.3

[PATCH V3 3/3] tools/perf: Fix parallel-perf python script to replace new python syntax ":=" usage

[Athira Rajeev]

perf test "perf script tests" fails as below in systems
with python 3.6

	File "/home/athira/linux/tools/perf/tests/shell/../../scripts/python/parallel-perf.py", line 442
	if line := p.stdout.readline():
             ^
	SyntaxError: invalid syntax
	--- Cleaning up ---
	---- end(-1) ----
	92: perf script tests: FAILED!

This happens because ":=" is a new syntax that assigns values
to variables as part of a larger expression. This is introduced
from python 3.8 and hence fails in setup with python 3.6
Address this by splitting the large expression and check the
value in two steps:
Previous line: if line := p.stdout.readline():
Current change:
	line = p.stdout.readline()
	if line:

With patch

	./perf test "perf script tests"
	 93: perf script tests:  Ok

Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
---
Changelog:
v1 -> v2
Added "Acked-by" from Adrian

 tools/perf/scripts/python/parallel-perf.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tools/perf/scripts/python/parallel-perf.py b/tools/perf/scripts/python/parallel-perf.py
index 21f32ec5ed46..be85fd7f6632 100755
--- a/tools/perf/scripts/python/parallel-perf.py
+++ b/tools/perf/scripts/python/parallel-perf.py
@@ -439,7 +439,8 @@ def ProcessCommandOutputLines(cmd, per_cpu, fn, *x):
 	pat = re.compile(r"\s*\[[0-9]+\]")
 	p = subprocess.Popen(cmd, stdout=subprocess.PIPE)
 	while True:
-		if line := p.stdout.readline():
+		line = p.stdout.readline()
+		if line:
 			line = line.decode("utf-8")
 			if pat.match(line):
 				line = line.split()
-- 
2.35.3

Re: [PATCH V3 1/3] tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

[Adrian Hunter]

On 18/06/24 17:03, Athira Rajeev wrote:
> 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.
> 
> With the fix,
> 	# ./perf test "test perf probe of function from different CU"
> 	117: test perf probe of function from different CU                   : Ok
> 
> Signed-off-by: Athira Rajeev<atrajeev@linux.vnet.ibm.com>
> ---
> Changelog:
> v2 -> v3:
> Addressed review comment from Adrian and James.
> Added perf_pid_map_tid to save the tid and modified
> is_perf_pid_map_name to use this internally.
> 
> v1 -> v2:
> Addressed review comments from Adrian.
> Added helper function is_perf_pid_map_name to check
> dso name of form "/tmp/perf-%d.map". Used sscanf
> instead of regex comparison.
> 
>  tools/perf/util/dso.c    | 12 ++++++++++++
>  tools/perf/util/dso.h    |  4 ++++
>  tools/perf/util/symbol.c |  3 ++-
>  3 files changed, 18 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
> index dde706b71da7..2340c4f6d0c2 100644
> --- a/tools/perf/util/dso.c
> +++ b/tools/perf/util/dso.c
> @@ -1652,3 +1652,15 @@ int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
>  	scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
>  	return 0;
>  }
> +
> +bool perf_pid_map_tid(const char *dso_name, int *tid)
> +{
> +	return sscanf(dso_name, "/tmp/perf-%d.map", tid) == 1;
> +}
> +
> +bool is_perf_pid_map_name(const char *dso_name)
> +{
> +	int tid;
> +
> +	return perf_pid_map_tid(dso_name, &tid);
> +}
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index df2c98402af3..d72f3b8c37f6 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -809,4 +809,8 @@ void reset_fd_limit(void);
>  u64 dso__find_global_type(struct dso *dso, u64 addr);
>  u64 dso__findnew_global_type(struct dso *dso, u64 addr, u64 offset);
>  
> +/* Check if dso name is of format "/tmp/perf-%d.map" */
> +bool perf_pid_map_tid(const char *dso_name, int *tid);
> +bool is_perf_pid_map_name(const char *dso_name);
> +
>  #endif /* __PERF_DSO */
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 9e5940b5bc59..aee0a4cfb383 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1799,7 +1799,8 @@ int dso__load(struct dso *dso, struct map *map)
>  	const char *map_path = dso__long_name(dso);
>  
>  	mutex_lock(dso__lock(dso));
> -	perfmap = strncmp(dso__name(dso), "/tmp/perf-", 10) == 0;
> +	perfmap = is_perf_pid_map_name(map_path);

If intended, the change from dso__name(dso) to dso__long_name(dso)
needs explanation in the commit message

> +
>  	if (perfmap) {
>  		if (dso__nsinfo(dso) &&
>  		    (dso__find_perf_map(newmapname, sizeof(newmapname),

Re: [PATCH V3 1/3] tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

[Chaitanya S Prakash]

On 6/18/24 19:33, Athira Rajeev wrote:
> 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.
>
> With the fix,
> 	# ./perf test "test perf probe of function from different CU"
> 	117: test perf probe of function from different CU                   : Ok
>
> Signed-off-by: Athira Rajeev<atrajeev@linux.vnet.ibm.com>
> ---
> Changelog:
> v2 -> v3:
> Addressed review comment from Adrian and James.
> Added perf_pid_map_tid to save the tid and modified
> is_perf_pid_map_name to use this internally.
>
> v1 -> v2:
> Addressed review comments from Adrian.
> Added helper function is_perf_pid_map_name to check
> dso name of form "/tmp/perf-%d.map". Used sscanf
> instead of regex comparison.
>
>   tools/perf/util/dso.c    | 12 ++++++++++++
>   tools/perf/util/dso.h    |  4 ++++
>   tools/perf/util/symbol.c |  3 ++-
>   3 files changed, 18 insertions(+), 1 deletion(-)
>
> diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
> index dde706b71da7..2340c4f6d0c2 100644
> --- a/tools/perf/util/dso.c
> +++ b/tools/perf/util/dso.c
> @@ -1652,3 +1652,15 @@ int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
>   	scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
>   	return 0;
>   }
> +
> +bool perf_pid_map_tid(const char *dso_name, int *tid)
> +{
> +	return sscanf(dso_name, "/tmp/perf-%d.map", tid) == 1;
> +}
> +
> +bool is_perf_pid_map_name(const char *dso_name)
> +{
> +	int tid;
> +
> +	return perf_pid_map_tid(dso_name, &tid);
> +}
> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
> index df2c98402af3..d72f3b8c37f6 100644
> --- a/tools/perf/util/dso.h
> +++ b/tools/perf/util/dso.h
> @@ -809,4 +809,8 @@ void reset_fd_limit(void);
>   u64 dso__find_global_type(struct dso *dso, u64 addr);
>   u64 dso__findnew_global_type(struct dso *dso, u64 addr, u64 offset);
>   
> +/* Check if dso name is of format "/tmp/perf-%d.map" */
> +bool perf_pid_map_tid(const char *dso_name, int *tid);
> +bool is_perf_pid_map_name(const char *dso_name);
> +
>   #endif /* __PERF_DSO */
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 9e5940b5bc59..aee0a4cfb383 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -1799,7 +1799,8 @@ int dso__load(struct dso *dso, struct map *map)
>   	const char *map_path = dso__long_name(dso);
>   
>   	mutex_lock(dso__lock(dso));
> -	perfmap = strncmp(dso__name(dso), "/tmp/perf-", 10) == 0;
> +	perfmap = is_perf_pid_map_name(map_path);
> +
>   	if (perfmap) {
>   		if (dso__nsinfo(dso) &&
>   		    (dso__find_perf_map(newmapname, sizeof(newmapname),

Reviewed-by: Chaitanya S Prakash<chaitanyas.prakash@arm.com>

I will drop my fix for the same.
https://lore.kernel.org/all/20240601125946.1741414-10-ChaitanyaS.Prakash@arm.com/

The rest of my series can be reviewed as a string function tidy up.

Re: [PATCH V3 1/3] tools/perf: Fix the string match for "/tmp/perf-$PID.map" files in dso__load

[Athira Rajeev]

> On 23 Jun 2024, at 8:56 PM, Chaitanya S Prakash <chaitanyas.prakash@arm.com> wrote:
> 
> 
> On 6/18/24 19:33, Athira Rajeev wrote:
>> 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.
>> 
>> With the fix,
>> # ./perf test "test perf probe of function from different CU"
>> 117: test perf probe of function from different CU                   : Ok
>> 
>> Signed-off-by: Athira Rajeev<atrajeev@linux.vnet.ibm.com>
>> ---
>> Changelog:
>> v2 -> v3:
>> Addressed review comment from Adrian and James.
>> Added perf_pid_map_tid to save the tid and modified
>> is_perf_pid_map_name to use this internally.
>> 
>> v1 -> v2:
>> Addressed review comments from Adrian.
>> Added helper function is_perf_pid_map_name to check
>> dso name of form "/tmp/perf-%d.map". Used sscanf
>> instead of regex comparison.
>> 
>>  tools/perf/util/dso.c    | 12 ++++++++++++
>>  tools/perf/util/dso.h    |  4 ++++
>>  tools/perf/util/symbol.c |  3 ++-
>>  3 files changed, 18 insertions(+), 1 deletion(-)
>> 
>> diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c
>> index dde706b71da7..2340c4f6d0c2 100644
>> --- a/tools/perf/util/dso.c
>> +++ b/tools/perf/util/dso.c
>> @@ -1652,3 +1652,15 @@ int dso__strerror_load(struct dso *dso, char *buf, size_t buflen)
>>   scnprintf(buf, buflen, "%s", dso_load__error_str[idx]);
>>   return 0;
>>  }
>> +
>> +bool perf_pid_map_tid(const char *dso_name, int *tid)
>> +{
>> + return sscanf(dso_name, "/tmp/perf-%d.map", tid) == 1;
>> +}
>> +
>> +bool is_perf_pid_map_name(const char *dso_name)
>> +{
>> + int tid;
>> +
>> + return perf_pid_map_tid(dso_name, &tid);
>> +}
>> diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h
>> index df2c98402af3..d72f3b8c37f6 100644
>> --- a/tools/perf/util/dso.h
>> +++ b/tools/perf/util/dso.h
>> @@ -809,4 +809,8 @@ void reset_fd_limit(void);
>>  u64 dso__find_global_type(struct dso *dso, u64 addr);
>>  u64 dso__findnew_global_type(struct dso *dso, u64 addr, u64 offset);
>>  +/* Check if dso name is of format "/tmp/perf-%d.map" */
>> +bool perf_pid_map_tid(const char *dso_name, int *tid);
>> +bool is_perf_pid_map_name(const char *dso_name);
>> +
>>  #endif /* __PERF_DSO */
>> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
>> index 9e5940b5bc59..aee0a4cfb383 100644
>> --- a/tools/perf/util/symbol.c
>> +++ b/tools/perf/util/symbol.c
>> @@ -1799,7 +1799,8 @@ int dso__load(struct dso *dso, struct map *map)
>>   const char *map_path = dso__long_name(dso);
>>     mutex_lock(dso__lock(dso));
>> - perfmap = strncmp(dso__name(dso), "/tmp/perf-", 10) == 0;
>> + perfmap = is_perf_pid_map_name(map_path);
>> +
>>   if (perfmap) {
>>   if (dso__nsinfo(dso) &&
>>      (dso__find_perf_map(newmapname, sizeof(newmapname),
> 
> Reviewed-by: Chaitanya S Prakash<chaitanyas.prakash@arm.com>

Thanks Chaitanya for the reviewed-by

Athira
> 
> I will drop my fix for the same.
> https://lore.kernel.org/all/20240601125946.1741414-10-ChaitanyaS.Prakash@arm.com/
> 
> The rest of my series can be reviewed as a string function tidy up.
>