On 23/06/24 09:48, 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. 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 > > Signed-off-by: Athira Rajeev<atraj...@linux.vnet.ibm.com>
Reviewed-by: Adrian Hunter <adrian.hun...@intel.com> > --- > Changelog: > v3 -> v4: > Added commit message with usage of dso__long_name > > 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),