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* [PATCH] perf tools: fix callstack entries and nr print message
@ 2022-05-09 11:47 Chengdong Li
  2022-05-09 13:45 ` Jiri Olsa
  0 siblings, 1 reply; 7+ messages in thread
From: Chengdong Li @ 2022-05-09 11:47 UTC (permalink / raw)
  To: alexey.v.bayduraev, peterz, mingo, acme, mark.rutland,
	alexander.shishkin, jolsa, namhyung, rickyman7, adrian.hunter,
	irogers, german.gomez, linux-perf-users, linux-kernel
  Cc: ak, likexu, chengdongli

From: Chengdong Li <chengdongli@tencent.com>

when generating callstack information from branch_stack(Intel LBR),
the actual number of callstack entry should be bigger than the number
of branch_stack, for example:

	branch_stack records:
		B() -> C()
		A() -> B()
	converted callstack records should be:
		C()
		B()
		A()
though, the number of callstack equals
to the number of branch stack plus 1.

This patch fix above issue in branch_stack__printf(). For example,

	# echo 'scale=2000; 4*a(1)' > cmd
	# perf record --call-graph lbr bc -l < cmd

Before applying this patch, `perf script -D` output:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:6    # which is not consistent with LBR records.
	.....  0: 000000000040a410
	.....  1: 0000000000408650    # ditto
	.....  2: 00000000004022f2
	.....  3: 00000000004015f5
	.....  4: 00007f5ed6dcb553
	.....  5: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

After applied:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:7
	.....  0: 000000000040a410
	.....  1: 000000000040573c
	.....  2: 0000000000408650
	.....  3: 00000000004022f2
	.....  4: 00000000004015f5
	.....  5: 00007f5ed6dcb553
	.....  6: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

Signed-off-by: Chengdong Li <chengdongli@tencent.com>
---
 tools/perf/util/session.c | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index f9a320694b85..568a1db98686 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1151,9 +1151,19 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 	struct branch_entry *entries = perf_sample__branch_entries(sample);
 	uint64_t i;
 
-	printf("%s: nr:%" PRIu64 "\n",
-		!callstack ? "... branch stack" : "... branch callstack",
-		sample->branch_stack->nr);
+	if (!callstack)
+		printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
+	else
+		/* the reason of adding 1 to nr is because after expanding
+		 * branch stack it generates nr + 1 callstack records. e.g.,
+		 *         B()->C()
+		 *         A()->B()
+		 * the final callstack should be:
+		 *         C()
+		 *         B()
+		 *         A()
+		 */
+		printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);
 
 	for (i = 0; i < sample->branch_stack->nr; i++) {
 		struct branch_entry *e = &entries[i];
@@ -1169,8 +1179,12 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 				(unsigned)e->flags.reserved,
 				e->flags.type ? branch_type_name(e->flags.type) : "");
 		} else {
-			printf("..... %2"PRIu64": %016" PRIx64 "\n",
-				i, i > 0 ? e->from : e->to);
+			if (i == 0)
+				printf("..... %2"PRIu64": %016" PRIx64 "\n"
+				       "..... %2"PRIu64": %016" PRIx64 "\n",
+						i, e->to, i+1, e->from);
+			else
+				printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);
 		}
 	}
 }
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 7+ messages in thread
* Re: [PATCH] perf tools: fix callstack entries and nr print message
  2022-05-09 11:47 [PATCH] perf tools: fix callstack entries and nr print message Chengdong Li
@ 2022-05-09 13:45 ` Jiri Olsa
  2022-05-10  0:40   ` [PATCH v2] " Chengdong Li
  2022-05-17  1:57   ` [RESEND PATCH " Chengdong Li
  0 siblings, 2 replies; 7+ messages in thread
From: Jiri Olsa @ 2022-05-09 13:45 UTC (permalink / raw)
  To: Chengdong Li
  Cc: alexey.v.bayduraev, peterz, mingo, acme, mark.rutland,
	alexander.shishkin, jolsa, namhyung, rickyman7, adrian.hunter,
	irogers, german.gomez, linux-perf-users, linux-kernel, ak,
	likexu, chengdongli

On Mon, May 09, 2022 at 07:47:43PM +0800, Chengdong Li wrote:
> From: Chengdong Li <chengdongli@tencent.com>
> 
> when generating callstack information from branch_stack(Intel LBR),
> the actual number of callstack entry should be bigger than the number
> of branch_stack, for example:
> 
> 	branch_stack records:
> 		B() -> C()
> 		A() -> B()
> 	converted callstack records should be:
> 		C()
> 		B()
> 		A()
> though, the number of callstack equals
> to the number of branch stack plus 1.
> 
> This patch fix above issue in branch_stack__printf(). For example,
> 
> 	# echo 'scale=2000; 4*a(1)' > cmd
> 	# perf record --call-graph lbr bc -l < cmd
> 
> Before applying this patch, `perf script -D` output:
> 
> 	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
> 	... LBR call chain: nr:8
> 	.....  0: fffffffffffffe00
> 	.....  1: 000000000040a410
> 	.....  2: 000000000040573c
> 	.....  3: 0000000000408650
> 	.....  4: 00000000004022f2
> 	.....  5: 00000000004015f5
> 	.....  6: 00007f5ed6dcb553
> 	.....  7: 0000000000401698
> 	... FP chain: nr:2
> 	.....  0: fffffffffffffe00
> 	.....  1: 000000000040a6d8
> 	... branch callstack: nr:6    # which is not consistent with LBR records.
> 	.....  0: 000000000040a410
> 	.....  1: 0000000000408650    # ditto
> 	.....  2: 00000000004022f2
> 	.....  3: 00000000004015f5
> 	.....  4: 00007f5ed6dcb553
> 	.....  5: 0000000000401698
> 	 ... thread: bc:17990
> 	 ...... dso: /usr/bin/bc
> 	bc 17990 1220022.677386:     894172 cycles:
> 			  40a410 [unknown] (/usr/bin/bc)
> 			  40573c [unknown] (/usr/bin/bc)
> 			  408650 [unknown] (/usr/bin/bc)
> 			  4022f2 [unknown] (/usr/bin/bc)
> 			  4015f5 [unknown] (/usr/bin/bc)
> 		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
> 			  401698 [unknown] (/usr/bin/bc)
> 
> After applied:
> 
> 	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
> 	... LBR call chain: nr:8
> 	.....  0: fffffffffffffe00
> 	.....  1: 000000000040a410
> 	.....  2: 000000000040573c
> 	.....  3: 0000000000408650
> 	.....  4: 00000000004022f2
> 	.....  5: 00000000004015f5
> 	.....  6: 00007f5ed6dcb553
> 	.....  7: 0000000000401698
> 	... FP chain: nr:2
> 	.....  0: fffffffffffffe00
> 	.....  1: 000000000040a6d8
> 	... branch callstack: nr:7
> 	.....  0: 000000000040a410
> 	.....  1: 000000000040573c
> 	.....  2: 0000000000408650
> 	.....  3: 00000000004022f2
> 	.....  4: 00000000004015f5
> 	.....  5: 00007f5ed6dcb553
> 	.....  6: 0000000000401698
> 	 ... thread: bc:17990
> 	 ...... dso: /usr/bin/bc
> 	bc 17990 1220022.677386:     894172 cycles:
> 			  40a410 [unknown] (/usr/bin/bc)
> 			  40573c [unknown] (/usr/bin/bc)
> 			  408650 [unknown] (/usr/bin/bc)
> 			  4022f2 [unknown] (/usr/bin/bc)
> 			  4015f5 [unknown] (/usr/bin/bc)
> 		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
> 			  401698 [unknown] (/usr/bin/bc)
> 
> Signed-off-by: Chengdong Li <chengdongli@tencent.com>
> ---
>  tools/perf/util/session.c | 24 +++++++++++++++++++-----
>  1 file changed, 19 insertions(+), 5 deletions(-)
> 
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index f9a320694b85..568a1db98686 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -1151,9 +1151,19 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>  	struct branch_entry *entries = perf_sample__branch_entries(sample);
>  	uint64_t i;
>  
> -	printf("%s: nr:%" PRIu64 "\n",
> -		!callstack ? "... branch stack" : "... branch callstack",
> -		sample->branch_stack->nr);
> +	if (!callstack)
> +		printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
> +	else
> +		/* the reason of adding 1 to nr is because after expanding
> +		 * branch stack it generates nr + 1 callstack records. e.g.,
> +		 *         B()->C()
> +		 *         A()->B()
> +		 * the final callstack should be:
> +		 *         C()
> +		 *         B()
> +		 *         A()
> +		 */
> +		printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);

please use { }

>  
>  	for (i = 0; i < sample->branch_stack->nr; i++) {
>  		struct branch_entry *e = &entries[i];
> @@ -1169,8 +1179,12 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>  				(unsigned)e->flags.reserved,
>  				e->flags.type ? branch_type_name(e->flags.type) : "");
>  		} else {
> -			printf("..... %2"PRIu64": %016" PRIx64 "\n",
> -				i, i > 0 ? e->from : e->to);
> +			if (i == 0)
> +				printf("..... %2"PRIu64": %016" PRIx64 "\n"
> +				       "..... %2"PRIu64": %016" PRIx64 "\n",
> +						i, e->to, i+1, e->from);
> +			else
> +				printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);

same here

thanks,
jirka

^ permalink raw reply	[flat|nested] 7+ messages in thread
* [PATCH v2] perf tools: fix callstack entries and nr print message
  2022-05-09 13:45 ` Jiri Olsa
@ 2022-05-10  0:40   ` Chengdong Li
  2022-05-11  1:35     ` Bryton Lee
  2022-05-17  1:57   ` [RESEND PATCH " Chengdong Li
  1 sibling, 1 reply; 7+ messages in thread
From: Chengdong Li @ 2022-05-10  0:40 UTC (permalink / raw)
  To: alexey.v.bayduraev, peterz, mingo, acme, mark.rutland,
	alexander.shishkin, jolsa, namhyung, rickyman7, adrian.hunter,
	irogers, german.gomez, linux-perf-users, linux-kernel
  Cc: ak, likexu, chengdongli

From: Chengdong Li <chengdongli@tencent.com>

when generating callstack information from branch_stack(Intel LBR),
the actual number of callstack entry should be bigger than the number
of branch_stack, for example:

	branch_stack records:
		B() -> C()
		A() -> B()
	converted callstack records should be:
		C()
		B()
		A()
though, the number of callstack equals
to the number of branch stack plus 1.

This patch fixes above issue in branch_stack__printf(). For example,

	# echo 'scale=2000; 4*a(1)' > cmd
	# perf record --call-graph lbr bc -l < cmd

Before applying this patch, `perf script -D` output:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:6    # which is not consistent with LBR records.
	.....  0: 000000000040a410
	.....  1: 0000000000408650    # ditto
	.....  2: 00000000004022f2
	.....  3: 00000000004015f5
	.....  4: 00007f5ed6dcb553
	.....  5: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

After applied:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:7
	.....  0: 000000000040a410
	.....  1: 000000000040573c
	.....  2: 0000000000408650
	.....  3: 00000000004022f2
	.....  4: 00000000004015f5
	.....  5: 00007f5ed6dcb553
	.....  6: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

Change from v1:
	- refined code style according to Jiri's review comments.

Signed-off-by: Chengdong Li <chengdongli@tencent.com>
---
 tools/perf/util/session.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index f9a320694b85..a7f93f5a1ac8 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1151,9 +1151,20 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 	struct branch_entry *entries = perf_sample__branch_entries(sample);
 	uint64_t i;
 
-	printf("%s: nr:%" PRIu64 "\n",
-		!callstack ? "... branch stack" : "... branch callstack",
-		sample->branch_stack->nr);
+	if (!callstack) {
+		printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
+	} else {
+		/* the reason of adding 1 to nr is because after expanding
+		 * branch stack it generates nr + 1 callstack records. e.g.,
+		 *         B()->C()
+		 *         A()->B()
+		 * the final callstack should be:
+		 *         C()
+		 *         B()
+		 *         A()
+		 */
+		printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);
+	}
 
 	for (i = 0; i < sample->branch_stack->nr; i++) {
 		struct branch_entry *e = &entries[i];
@@ -1169,8 +1180,13 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 				(unsigned)e->flags.reserved,
 				e->flags.type ? branch_type_name(e->flags.type) : "");
 		} else {
-			printf("..... %2"PRIu64": %016" PRIx64 "\n",
-				i, i > 0 ? e->from : e->to);
+			if (i == 0) {
+				printf("..... %2"PRIu64": %016" PRIx64 "\n"
+				       "..... %2"PRIu64": %016" PRIx64 "\n",
+						i, e->to, i+1, e->from);
+			} else {
+				printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);
+			}
 		}
 	}
 }
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 7+ messages in thread
* Re: [PATCH v2] perf tools: fix callstack entries and nr print message
  2022-05-10  0:40   ` [PATCH v2] " Chengdong Li
@ 2022-05-11  1:35     ` Bryton Lee
  0 siblings, 0 replies; 7+ messages in thread
From: Bryton Lee @ 2022-05-11  1:35 UTC (permalink / raw)
  To: jolsa, linux-perf-users, linux-kernel
  Cc: ak, likexu, chengdongli, mark.rutland, mingo,
	Arnaldo Carvalho de Melo, Adrian Hunter, alexander.shishkin,
	irogers, german.gomez, rickyman7, Namhyung Kim, peterz,
	alexey.v.bayduraev

Hi Jiri,

Could you kindly review my patch again? I sent out my updates
yesterday. I am happy to know your guidance.

Thanks,
Chengdong

On Tue, May 10, 2022 at 8:41 AM Chengdong Li <brytonlee01@gmail.com> wrote:
>
> From: Chengdong Li <chengdongli@tencent.com>
>
> when generating callstack information from branch_stack(Intel LBR),
> the actual number of callstack entry should be bigger than the number
> of branch_stack, for example:
>
>         branch_stack records:
>                 B() -> C()
>                 A() -> B()
>         converted callstack records should be:
>                 C()
>                 B()
>                 A()
> though, the number of callstack equals
> to the number of branch stack plus 1.
>
> This patch fixes above issue in branch_stack__printf(). For example,
>
>         # echo 'scale=2000; 4*a(1)' > cmd
>         # perf record --call-graph lbr bc -l < cmd
>
> Before applying this patch, `perf script -D` output:
>
>         1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
>         ... LBR call chain: nr:8
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a410
>         .....  2: 000000000040573c
>         .....  3: 0000000000408650
>         .....  4: 00000000004022f2
>         .....  5: 00000000004015f5
>         .....  6: 00007f5ed6dcb553
>         .....  7: 0000000000401698
>         ... FP chain: nr:2
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a6d8
>         ... branch callstack: nr:6    # which is not consistent with LBR records.
>         .....  0: 000000000040a410
>         .....  1: 0000000000408650    # ditto
>         .....  2: 00000000004022f2
>         .....  3: 00000000004015f5
>         .....  4: 00007f5ed6dcb553
>         .....  5: 0000000000401698
>          ... thread: bc:17990
>          ...... dso: /usr/bin/bc
>         bc 17990 1220022.677386:     894172 cycles:
>                           40a410 [unknown] (/usr/bin/bc)
>                           40573c [unknown] (/usr/bin/bc)
>                           408650 [unknown] (/usr/bin/bc)
>                           4022f2 [unknown] (/usr/bin/bc)
>                           4015f5 [unknown] (/usr/bin/bc)
>                     7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
>                           401698 [unknown] (/usr/bin/bc)
>
> After applied:
>
>         1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
>         ... LBR call chain: nr:8
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a410
>         .....  2: 000000000040573c
>         .....  3: 0000000000408650
>         .....  4: 00000000004022f2
>         .....  5: 00000000004015f5
>         .....  6: 00007f5ed6dcb553
>         .....  7: 0000000000401698
>         ... FP chain: nr:2
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a6d8
>         ... branch callstack: nr:7
>         .....  0: 000000000040a410
>         .....  1: 000000000040573c
>         .....  2: 0000000000408650
>         .....  3: 00000000004022f2
>         .....  4: 00000000004015f5
>         .....  5: 00007f5ed6dcb553
>         .....  6: 0000000000401698
>          ... thread: bc:17990
>          ...... dso: /usr/bin/bc
>         bc 17990 1220022.677386:     894172 cycles:
>                           40a410 [unknown] (/usr/bin/bc)
>                           40573c [unknown] (/usr/bin/bc)
>                           408650 [unknown] (/usr/bin/bc)
>                           4022f2 [unknown] (/usr/bin/bc)
>                           4015f5 [unknown] (/usr/bin/bc)
>                     7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
>                           401698 [unknown] (/usr/bin/bc)
>
> Change from v1:
>         - refined code style according to Jiri's review comments.
>
> Signed-off-by: Chengdong Li <chengdongli@tencent.com>
> ---
>  tools/perf/util/session.c | 26 +++++++++++++++++++++-----
>  1 file changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index f9a320694b85..a7f93f5a1ac8 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -1151,9 +1151,20 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>         struct branch_entry *entries = perf_sample__branch_entries(sample);
>         uint64_t i;
>
> -       printf("%s: nr:%" PRIu64 "\n",
> -               !callstack ? "... branch stack" : "... branch callstack",
> -               sample->branch_stack->nr);
> +       if (!callstack) {
> +               printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
> +       } else {
> +               /* the reason of adding 1 to nr is because after expanding
> +                * branch stack it generates nr + 1 callstack records. e.g.,
> +                *         B()->C()
> +                *         A()->B()
> +                * the final callstack should be:
> +                *         C()
> +                *         B()
> +                *         A()
> +                */
> +               printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);
> +       }
>
>         for (i = 0; i < sample->branch_stack->nr; i++) {
>                 struct branch_entry *e = &entries[i];
> @@ -1169,8 +1180,13 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>                                 (unsigned)e->flags.reserved,
>                                 e->flags.type ? branch_type_name(e->flags.type) : "");
>                 } else {
> -                       printf("..... %2"PRIu64": %016" PRIx64 "\n",
> -                               i, i > 0 ? e->from : e->to);
> +                       if (i == 0) {
> +                               printf("..... %2"PRIu64": %016" PRIx64 "\n"
> +                                      "..... %2"PRIu64": %016" PRIx64 "\n",
> +                                               i, e->to, i+1, e->from);
> +                       } else {
> +                               printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);
> +                       }
>                 }
>         }
>  }
> --
> 2.27.0
>


-- 
Best Regards

Bryton.Lee

^ permalink raw reply	[flat|nested] 7+ messages in thread
* [RESEND PATCH v2] perf tools: fix callstack entries and nr print message
  2022-05-09 13:45 ` Jiri Olsa
  2022-05-10  0:40   ` [PATCH v2] " Chengdong Li
@ 2022-05-17  1:57   ` Chengdong Li
  2022-05-17 23:14     ` Namhyung Kim
  1 sibling, 1 reply; 7+ messages in thread
From: Chengdong Li @ 2022-05-17  1:57 UTC (permalink / raw)
  To: alexey.v.bayduraev, peterz, mingo, acme, mark.rutland,
	alexander.shishkin, jolsa, namhyung, rickyman7, adrian.hunter,
	irogers, german.gomez, linux-perf-users, linux-kernel
  Cc: ak, likexu, chengdongli

From: Chengdong Li <chengdongli@tencent.com>

when generating callstack information from branch_stack(Intel LBR),
the actual number of callstack entry should be bigger than the number
of branch_stack, for example:

	branch_stack records:
		B() -> C()
		A() -> B()
	converted callstack records should be:
		C()
		B()
		A()
though, the number of callstack equals
to the number of branch stack plus 1.

This patch fixes above issue in branch_stack__printf(). For example,

	# echo 'scale=2000; 4*a(1)' > cmd
	# perf record --call-graph lbr bc -l < cmd

Before applying this patch, `perf script -D` output:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:6    # which is not consistent with LBR records.
	.....  0: 000000000040a410
	.....  1: 0000000000408650    # ditto
	.....  2: 00000000004022f2
	.....  3: 00000000004015f5
	.....  4: 00007f5ed6dcb553
	.....  5: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

After applied:

	1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
	... LBR call chain: nr:8
	.....  0: fffffffffffffe00
	.....  1: 000000000040a410
	.....  2: 000000000040573c
	.....  3: 0000000000408650
	.....  4: 00000000004022f2
	.....  5: 00000000004015f5
	.....  6: 00007f5ed6dcb553
	.....  7: 0000000000401698
	... FP chain: nr:2
	.....  0: fffffffffffffe00
	.....  1: 000000000040a6d8
	... branch callstack: nr:7
	.....  0: 000000000040a410
	.....  1: 000000000040573c
	.....  2: 0000000000408650
	.....  3: 00000000004022f2
	.....  4: 00000000004015f5
	.....  5: 00007f5ed6dcb553
	.....  6: 0000000000401698
	 ... thread: bc:17990
	 ...... dso: /usr/bin/bc
	bc 17990 1220022.677386:     894172 cycles:
			  40a410 [unknown] (/usr/bin/bc)
			  40573c [unknown] (/usr/bin/bc)
			  408650 [unknown] (/usr/bin/bc)
			  4022f2 [unknown] (/usr/bin/bc)
			  4015f5 [unknown] (/usr/bin/bc)
		    7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
			  401698 [unknown] (/usr/bin/bc)

Change from v1:
	- refined code style according to Jiri's review comments.

Signed-off-by: Chengdong Li <chengdongli@tencent.com>
---
 tools/perf/util/session.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index f9a320694b85..a7f93f5a1ac8 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1151,9 +1151,20 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 	struct branch_entry *entries = perf_sample__branch_entries(sample);
 	uint64_t i;
 
-	printf("%s: nr:%" PRIu64 "\n",
-		!callstack ? "... branch stack" : "... branch callstack",
-		sample->branch_stack->nr);
+	if (!callstack) {
+		printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
+	} else {
+		/* the reason of adding 1 to nr is because after expanding
+		 * branch stack it generates nr + 1 callstack records. e.g.,
+		 *         B()->C()
+		 *         A()->B()
+		 * the final callstack should be:
+		 *         C()
+		 *         B()
+		 *         A()
+		 */
+		printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);
+	}
 
 	for (i = 0; i < sample->branch_stack->nr; i++) {
 		struct branch_entry *e = &entries[i];
@@ -1169,8 +1180,13 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
 				(unsigned)e->flags.reserved,
 				e->flags.type ? branch_type_name(e->flags.type) : "");
 		} else {
-			printf("..... %2"PRIu64": %016" PRIx64 "\n",
-				i, i > 0 ? e->from : e->to);
+			if (i == 0) {
+				printf("..... %2"PRIu64": %016" PRIx64 "\n"
+				       "..... %2"PRIu64": %016" PRIx64 "\n",
+						i, e->to, i+1, e->from);
+			} else {
+				printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);
+			}
 		}
 	}
 }
-- 
2.27.0


^ permalink raw reply related	[flat|nested] 7+ messages in thread
* Re: [RESEND PATCH v2] perf tools: fix callstack entries and nr print message
  2022-05-17  1:57   ` [RESEND PATCH " Chengdong Li
@ 2022-05-17 23:14     ` Namhyung Kim
  2022-05-21 17:57       ` Arnaldo Carvalho de Melo
  0 siblings, 1 reply; 7+ messages in thread
From: Namhyung Kim @ 2022-05-17 23:14 UTC (permalink / raw)
  To: Chengdong Li
  Cc: Alexey Bayduraev, Peter Zijlstra, Ingo Molnar,
	Arnaldo Carvalho de Melo, Mark Rutland, Alexander Shishkin,
	Jiri Olsa, Riccardo Mancini, Adrian Hunter, Ian Rogers,
	German Gomez, linux-perf-users, linux-kernel, Andi Kleen, likexu,
	chengdongli

Hello,

On Mon, May 16, 2022 at 6:57 PM Chengdong Li <brytonlee01@gmail.com> wrote:
>
> From: Chengdong Li <chengdongli@tencent.com>
>
> when generating callstack information from branch_stack(Intel LBR),
> the actual number of callstack entry should be bigger than the number
> of branch_stack, for example:
>
>         branch_stack records:
>                 B() -> C()
>                 A() -> B()
>         converted callstack records should be:
>                 C()
>                 B()
>                 A()
> though, the number of callstack equals
> to the number of branch stack plus 1.
>
> This patch fixes above issue in branch_stack__printf(). For example,
>
>         # echo 'scale=2000; 4*a(1)' > cmd
>         # perf record --call-graph lbr bc -l < cmd
>
> Before applying this patch, `perf script -D` output:
>
>         1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
>         ... LBR call chain: nr:8
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a410
>         .....  2: 000000000040573c
>         .....  3: 0000000000408650
>         .....  4: 00000000004022f2
>         .....  5: 00000000004015f5
>         .....  6: 00007f5ed6dcb553
>         .....  7: 0000000000401698
>         ... FP chain: nr:2
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a6d8
>         ... branch callstack: nr:6    # which is not consistent with LBR records.
>         .....  0: 000000000040a410
>         .....  1: 0000000000408650    # ditto
>         .....  2: 00000000004022f2
>         .....  3: 00000000004015f5
>         .....  4: 00007f5ed6dcb553
>         .....  5: 0000000000401698
>          ... thread: bc:17990
>          ...... dso: /usr/bin/bc
>         bc 17990 1220022.677386:     894172 cycles:
>                           40a410 [unknown] (/usr/bin/bc)
>                           40573c [unknown] (/usr/bin/bc)
>                           408650 [unknown] (/usr/bin/bc)
>                           4022f2 [unknown] (/usr/bin/bc)
>                           4015f5 [unknown] (/usr/bin/bc)
>                     7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
>                           401698 [unknown] (/usr/bin/bc)
>
> After applied:
>
>         1220022677386876 0x2a40 [0xd8]: PERF_RECORD_SAMPLE(IP, 0x4002): 17990/17990: 0x40a6d6 period: 894172 addr: 0
>         ... LBR call chain: nr:8
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a410
>         .....  2: 000000000040573c
>         .....  3: 0000000000408650
>         .....  4: 00000000004022f2
>         .....  5: 00000000004015f5
>         .....  6: 00007f5ed6dcb553
>         .....  7: 0000000000401698
>         ... FP chain: nr:2
>         .....  0: fffffffffffffe00
>         .....  1: 000000000040a6d8
>         ... branch callstack: nr:7
>         .....  0: 000000000040a410
>         .....  1: 000000000040573c
>         .....  2: 0000000000408650
>         .....  3: 00000000004022f2
>         .....  4: 00000000004015f5
>         .....  5: 00007f5ed6dcb553
>         .....  6: 0000000000401698
>          ... thread: bc:17990
>          ...... dso: /usr/bin/bc
>         bc 17990 1220022.677386:     894172 cycles:
>                           40a410 [unknown] (/usr/bin/bc)
>                           40573c [unknown] (/usr/bin/bc)
>                           408650 [unknown] (/usr/bin/bc)
>                           4022f2 [unknown] (/usr/bin/bc)
>                           4015f5 [unknown] (/usr/bin/bc)
>                     7f5ed6dcb553 __libc_start_main+0xf3 (/usr/lib64/libc-2.17.so)
>                           401698 [unknown] (/usr/bin/bc)
>
> Change from v1:
>         - refined code style according to Jiri's review comments.
>
> Signed-off-by: Chengdong Li <chengdongli@tencent.com>

Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks,
Namhyung


> ---
>  tools/perf/util/session.c | 26 +++++++++++++++++++++-----
>  1 file changed, 21 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index f9a320694b85..a7f93f5a1ac8 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -1151,9 +1151,20 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>         struct branch_entry *entries = perf_sample__branch_entries(sample);
>         uint64_t i;
>
> -       printf("%s: nr:%" PRIu64 "\n",
> -               !callstack ? "... branch stack" : "... branch callstack",
> -               sample->branch_stack->nr);
> +       if (!callstack) {
> +               printf("%s: nr:%" PRIu64 "\n", "... branch stack", sample->branch_stack->nr);
> +       } else {
> +               /* the reason of adding 1 to nr is because after expanding
> +                * branch stack it generates nr + 1 callstack records. e.g.,
> +                *         B()->C()
> +                *         A()->B()
> +                * the final callstack should be:
> +                *         C()
> +                *         B()
> +                *         A()
> +                */
> +               printf("%s: nr:%" PRIu64 "\n", "... branch callstack", sample->branch_stack->nr+1);
> +       }
>
>         for (i = 0; i < sample->branch_stack->nr; i++) {
>                 struct branch_entry *e = &entries[i];
> @@ -1169,8 +1180,13 @@ static void branch_stack__printf(struct perf_sample *sample, bool callstack)
>                                 (unsigned)e->flags.reserved,
>                                 e->flags.type ? branch_type_name(e->flags.type) : "");
>                 } else {
> -                       printf("..... %2"PRIu64": %016" PRIx64 "\n",
> -                               i, i > 0 ? e->from : e->to);
> +                       if (i == 0) {
> +                               printf("..... %2"PRIu64": %016" PRIx64 "\n"
> +                                      "..... %2"PRIu64": %016" PRIx64 "\n",
> +                                               i, e->to, i+1, e->from);
> +                       } else {
> +                               printf("..... %2"PRIu64": %016" PRIx64 "\n", i+1, e->from);
> +                       }
>                 }
>         }
>  }
> --
> 2.27.0
>

^ permalink raw reply	[flat|nested] 7+ messages in thread
* Re: [RESEND PATCH v2] perf tools: fix callstack entries and nr print message
  2022-05-17 23:14     ` Namhyung Kim
@ 2022-05-21 17:57       ` Arnaldo Carvalho de Melo
  0 siblings, 0 replies; 7+ messages in thread
From: Arnaldo Carvalho de Melo @ 2022-05-21 17:57 UTC (permalink / raw)
  To: Namhyung Kim
  Cc: Chengdong Li, Alexey Bayduraev, Peter Zijlstra, Ingo Molnar,
	Mark Rutland, Alexander Shishkin, Jiri Olsa, Riccardo Mancini,
	Adrian Hunter, Ian Rogers, German Gomez, linux-perf-users,
	linux-kernel, Andi Kleen, likexu, chengdongli

Em Tue, May 17, 2022 at 04:14:49PM -0700, Namhyung Kim escreveu:
> On Mon, May 16, 2022 at 6:57 PM Chengdong Li <brytonlee01@gmail.com> wrote:
> > Signed-off-by: Chengdong Li <chengdongli@tencent.com>
> 
> Acked-by: Namhyung Kim <namhyung@kernel.org>

Thanks, applied.

- Arnaldo


^ permalink raw reply	[flat|nested] 7+ messages in thread
end of thread, other threads:[~2022-05-21 17:58 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-09 11:47 [PATCH] perf tools: fix callstack entries and nr print message Chengdong Li
2022-05-09 13:45 ` Jiri Olsa
2022-05-10  0:40   ` [PATCH v2] " Chengdong Li
2022-05-11  1:35     ` Bryton Lee
2022-05-17  1:57   ` [RESEND PATCH " Chengdong Li
2022-05-17 23:14     ` Namhyung Kim
2022-05-21 17:57       ` Arnaldo Carvalho de Melo

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