diff mbox series

[tip:,perf/core] perf/amd/ibs: Make IBS a core pmu

Message ID 166929138346.4906.10749574210524260976.tip-bot2@tip-bot2
State New
Headers
Series [tip:,perf/core] perf/amd/ibs: Make IBS a core pmu |

Commit Message

tip-bot2 for Thomas Gleixner Nov. 24, 2022, 12:03 p.m. UTC 
  The following commit has been merged into the perf/core branch of tip:

Commit-ID:     30093056f7b2f759ff180d3a86d29f68315e469b
Gitweb:        https://git.kernel.org/tip/30093056f7b2f759ff180d3a86d29f68315e469b
Author:        Ravi Bangoria <ravi.bangoria@amd.com>
AuthorDate:    Tue, 15 Nov 2022 15:09:04 +05:30
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Thu, 24 Nov 2022 11:09:19 +01:00

perf/amd/ibs: Make IBS a core pmu

So far, only one pmu was allowed to be registered as core pmu and thus
IBS pmus were being registered as uncore. However, with the event context
rewrite, that limitation no longer exists and thus IBS pmus can also be
registered as core pmu. This makes IBS much more usable, for ex, user
will be able to do per-process precise monitoring on AMD:

Before patch:
  $ sudo perf record -e cycles:pp ls
  Error:
  Invalid event (cycles:pp) in per-thread mode, enable system wide with '-a'

After patch:
  $ sudo perf record -e cycles:pp ls
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data (33 samples) ]

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lkml.kernel.org/r/20221115093904.1799-1-ravi.bangoria@amd.com
---
 arch/x86/events/amd/ibs.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Borislav Petkov Dec. 8, 2022, 3:19 p.m. UTC | #1 
I believe this is one of the things Linus wanted to have on AMD hw.

On Thu, Nov 24, 2022 at 12:03:03PM -0000, tip-bot2 for Ravi Bangoria wrote:
> The following commit has been merged into the perf/core branch of tip:
> 
> Commit-ID:     30093056f7b2f759ff180d3a86d29f68315e469b
> Gitweb:        https://git.kernel.org/tip/30093056f7b2f759ff180d3a86d29f68315e469b
> Author:        Ravi Bangoria <ravi.bangoria@amd.com>
> AuthorDate:    Tue, 15 Nov 2022 15:09:04 +05:30
> Committer:     Peter Zijlstra <peterz@infradead.org>
> CommitterDate: Thu, 24 Nov 2022 11:09:19 +01:00
> 
> perf/amd/ibs: Make IBS a core pmu
> 
> So far, only one pmu was allowed to be registered as core pmu and thus
> IBS pmus were being registered as uncore. However, with the event context
> rewrite, that limitation no longer exists and thus IBS pmus can also be
> registered as core pmu. This makes IBS much more usable, for ex, user
> will be able to do per-process precise monitoring on AMD:
> 
> Before patch:
>   $ sudo perf record -e cycles:pp ls
>   Error:
>   Invalid event (cycles:pp) in per-thread mode, enable system wide with '-a'
> 
> After patch:
>   $ sudo perf record -e cycles:pp ls
>   [ perf record: Woken up 1 times to write data ]
>   [ perf record: Captured and wrote 0.017 MB perf.data (33 samples) ]
> 
> Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Acked-by: Ian Rogers <irogers@google.com>
> Link: https://lkml.kernel.org/r/20221115093904.1799-1-ravi.bangoria@amd.com
> ---
>  arch/x86/events/amd/ibs.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c
> index 3271735..fbc2ce8 100644
> --- a/arch/x86/events/amd/ibs.c
> +++ b/arch/x86/events/amd/ibs.c
> @@ -631,7 +631,7 @@ static const struct attribute_group *op_attr_update[] = {
>  
>  static struct perf_ibs perf_ibs_fetch = {
>  	.pmu = {
> -		.task_ctx_nr	= perf_invalid_context,
> +		.task_ctx_nr	= perf_hw_context,
>  
>  		.event_init	= perf_ibs_init,
>  		.add		= perf_ibs_add,
> @@ -655,7 +655,7 @@ static struct perf_ibs perf_ibs_fetch = {
>  
>  static struct perf_ibs perf_ibs_op = {
>  	.pmu = {
> -		.task_ctx_nr	= perf_invalid_context,
> +		.task_ctx_nr	= perf_hw_context,
>  
>  		.event_init	= perf_ibs_init,
>  		.add		= perf_ibs_add,
Ravi Bangoria Dec. 9, 2022, 3:32 a.m. UTC | #2 
On 08-Dec-22 8:49 PM, Borislav Petkov wrote:
> I believe this is one of the things Linus wanted to have on AMD hw.

Yes, https://lore.kernel.org/r/CAHk-=wgRm26_oT-JR+TRzDsfhD1TRxfWDM=j6kJerv+m=NU-yQ@mail.gmail.com

This patch solves per-thread profiling issue. However, -e cycles:p is
still root only because IBS hw does not support user/kernel filtering.

Thanks,
Ravi
diff mbox series

Patch

diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c
index 3271735..fbc2ce8 100644
--- a/arch/x86/events/amd/ibs.c
+++ b/arch/x86/events/amd/ibs.c
@@ -631,7 +631,7 @@  static const struct attribute_group *op_attr_update[] = {
 
 static struct perf_ibs perf_ibs_fetch = {
 	.pmu = {
-		.task_ctx_nr	= perf_invalid_context,
+		.task_ctx_nr	= perf_hw_context,
 
 		.event_init	= perf_ibs_init,
 		.add		= perf_ibs_add,
@@ -655,7 +655,7 @@  static struct perf_ibs perf_ibs_fetch = {
 
 static struct perf_ibs perf_ibs_op = {
 	.pmu = {
-		.task_ctx_nr	= perf_invalid_context,
+		.task_ctx_nr	= perf_hw_context,
 
 		.event_init	= perf_ibs_init,
 		.add		= perf_ibs_add,