LinuxLists.cc - [PATCH v5 0/5] perf report: Show inline stack

2017-03-16 13:44:38

Subject: [PATCH v5 0/5] perf report: Show inline stack

v5: Update according to Milian Wolff's comments. It groups by address
(then display file/ line), or by function (then display function name).

For example:

1. Show inlined function name
perf report --stdio -g function --inline

0.69% 0.00% inline ld-2.23.so [.] dl_main
|
---dl_main
|
--0.56%--_dl_relocate_object
_dl_relocate_object (inline)
elf_dynamic_do_Rela (inline)

2. Show the file/line information
perf report --stdio -g address --inline

0.69% 0.00% inline ld-2.23.so [.] _dl_start_user
|
---_dl_start_user .:0
_dl_start rtld.c:307
/build/glibc-GKVZIf/glibc-2.23/elf/rtld.c:413 (inline)
_dl_sysdep_start dl-sysdep.c:250
|
--0.56%--dl_main rtld.c:2076

2 patches are updated according to this change.
perf report: Show inline stack in browser mode
perf report: Show inline stack in stdio mode

3 patches are not changed.
perf report: Find the inline stack for a given address
perf report: Refactor common code in srcline.c
perf report: Create new inline option

v4: Remove the options "--inline-line" and "--inline-name". Just use
a new option "--inline" to print the inline function information.
The policy is if the inline function name can be resolved then
print the name in priority. If the name can't be resolved, then
print the source line number.

For example:
perf report --stdio --inline

0.69% 0.00% inline ld-2.23.so [.] dl_main
|
---dl_main
|
--0.56%--_dl_relocate_object
|
---_dl_relocate_object (inline)
elf_dynamic_do_Rela (inline)

Following 3 patches are updated according to this change.
perf report: Show inline stack in browser mode
perf report: Show inline stack in stdio mode
perf report: Create new inline option

Following are not changed.
perf report: Find the inline stack for a given address
perf report: Refactor common code in srcline.c

v3: Iterate on RIPs of all callchain entries to check if the RIP is in
inline functions.

Reverse the order of the inliner printout if necessary.

Provide new options "--inline-line" / "--inline-name" to print
inline function name or print inline function source line.

v2: Thanks so much for Arnaldo's comments!
The modifications are:

1. Divide v1 patch "perf report: Find the inline stack for a
given address" into 2 patches:
a. perf report: Refactor common code in srcline.c
b. perf report: Find the inline stack for a given address

Some function names are changed:
dso_name_get -> dso__name
ilist_apend -> inline_list__append
get_inline_node -> dso__parse_addr_inlines
free_inline_node -> inline_node__delete

2. Since the function name are changed, update following patches
accordingly.
a. perf report: Show inline stack in stdio mode
b. perf report: Show inline stack in browser mode

3. Rebase to latest perf/core branch. This patch is impacted.
a. perf report: Create a new option "--inline"

v1: Initial post

It would be useful for perf to support a mode to query the
inline stack for callgraph addresses. This would simplify
finding the right code in code that does a lot of inlining.

For example, the c code:

static inline void f3(void)
{
int i;
for (i = 0; i < 1000;) {

if(i%2)
i++;
else
i++;
}
printf("hello f3\n"); /* D */
}

/* < CALLCHAIN: f2 <- f1 > */
static inline void f2(void)
{
int i;
for (i = 0; i < 100; i++) {
f3(); /* C */
}
}

/* < CALLCHAIN: f1 <- main > */
static inline void f1(void)
{
int i;
for (i = 0; i < 100; i++) {
f2(); /* B */
}
}

/* < CALLCHAIN: main <- TOP > */
int main()
{
struct timeval tv;
time_t start, end;

gettimeofday(&tv, NULL);
start = end = tv.tv_sec;
while((end - start) < 5) {
f1(); /* A */
gettimeofday(&tv, NULL);
end = tv.tv_sec;
}
return 0;
}

The printed inline stack is:

0.05% test2 test2 [.] main
|
---/home/perf-dev/lck-2867/test/test2.c:27 (inline)
/home/perf-dev/lck-2867/test/test2.c:35 (inline)
/home/perf-dev/lck-2867/test/test2.c:45 (inline)
/home/perf-dev/lck-2867/test/test2.c:61 (inline)

I tag A/B/C/D in above c code to indicate the source line,
actually the inline stack is equal to:

0.05% test2 test2 [.] main
|
---D
C
B
A

Jin Yao (5):
perf report: Refactor common code in srcline.c
perf report: Find the inline stack for a given address
perf report: Create new inline option
perf report: Show inline stack for stdio mode
perf report: Show inline stack for browser mode

tools/perf/Documentation/perf-report.txt | 4 +
tools/perf/builtin-report.c | 2 +
tools/perf/ui/browsers/hists.c | 171 ++++++++++++++++++++--
tools/perf/ui/stdio/hist.c | 79 ++++++++++-
tools/perf/util/hist.c | 5 +
tools/perf/util/sort.h | 1 +
tools/perf/util/srcline.c | 237 +++++++++++++++++++++++++++----
tools/perf/util/symbol-elf.c | 5 +
tools/perf/util/symbol.h | 5 +-
tools/perf/util/util.h | 16 +++
10 files changed, 487 insertions(+), 38 deletions(-)

--
2.7.4

2017-03-16 13:44:39

by Jin Yao

[permalink] [raw]

[permalink] [raw]

Subject: Re: [PATCH v5 2/5] perf report: Find the inline stack for a given address

Hi Ravi, Arnaldo,

The build error happens when BFD lib is not set in build environment.

Anyway the patch series should be improved to get better compatibility
for this case. For easy patch management, I send the v6 patch series for
fixing this issue. Very sorry for the inconvenience.

Thanks

Jin Yao

On 3/25/2017 3:18 PM, Ravi Bangoria wrote:
> Hi Jin / Arnaldo,
>
> I see a build failure with this patch:
>
> On Friday 17 March 2017 03:12 AM, Jin Yao wrote:
>> It would be useful for perf to support a mode to query the
>> inline stack for a given callgraph address. This would simplify
>> finding the right code in code that does a lot of inlining.
>>
>> The srcline.c has contained the code which supports to translate
>> the address to filename:line_nr. This patch just extends the
>> function to let it support getting the inline stacks.
> ...
>> + while (getline(&filename, &len, fp) != -1) {
>> + if (filename_split(filename, &line_nr) != 1) {
>> + free(filename);
>> + goto out;
>> + }
>> +
>> + if (inline_list__append(filename, NULL, line_nr, node) != 0)
> util/srcline.c: In function ?addr2inlines?:
> util/srcline.c:403:7: error: too few arguments to function ?inline_list__append?
> if (inline_list__append(filename, NULL, line_nr, node) != 0)
> ^
> util/srcline.c:34:12: note: declared here
> static int inline_list__append(char *filename, char *funcname, int line_nr,
> ^
> util/srcline.c: At top level:
> util/srcline.c:60:13: error: ?inline_list__reverse? defined but not used [-Werror=unused-function]
> static void inline_list__reverse(struct inline_node *node)
> ^
> cc1: all warnings being treated as errors
> mv: cannot stat ?util/.srcline.o.tmp?: No such file or directory
>
> Thanks,
> Ravi
>