2019-06-28 21:59:56

by Kim Phillips

[permalink] [raw]
Subject: [PATCH 1/2 RESEND3] perf/x86/amd/uncore: Do not set ThreadMask and SliceMask for non-L3 PMCs

From: Kim Phillips <[email protected]>

Commit d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask
for L3 Cache perf events") enables L3 PMC events for all threads and
slices by writing 1s in ChL3PmcCfg (L3 PMC PERF_CTL) register fields.

Those bitfields overlap with high order event select bits in the Data
Fabric PMC control register, however.

So when a user requests raw Data Fabric events (-e amd_df/event=0xYYY/),
the two highest order bits get inadvertently set, changing the counter
select to events that don't exist, and for which no counts are read.

This patch changes the logic to write the L3 masks only when dealing
with L3 PMC counters.

AMD Family 16h and below Northbridge (NB) counters were not affected.

Signed-off-by: Kim Phillips <[email protected]>
Cc: <[email protected]> # v4.19+
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Martin Liska <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Cc: Janakarajan Natarajan <[email protected]>
Cc: Gary Hook <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected]
Fixes: d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events")
---
RESEND3: file sent with header:

Content-Type: text/plain; charset="us-ascii"

to work around a bug in the Microsoft Outlook SMTP servers.

arch/x86/events/amd/uncore.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index 85e6984c560b..c2c4ae5fbbfc 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -206,7 +206,7 @@ static int amd_uncore_event_init(struct perf_event *event)
* SliceMask and ThreadMask need to be set for certain L3 events in
* Family 17h. For other events, the two fields do not affect the count.
*/
- if (l3_mask)
+ if (l3_mask && is_llc_event(event))
hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);

if (event->cpu < 0)
--
2.22.0


2019-06-28 22:00:38

by Kim Phillips

[permalink] [raw]
Subject: [PATCH 2/2 RESEND3] perf/x86/amd/uncore: set the thread mask for F17h L3 PMCs

From: Kim Phillips <[email protected]>

Fill in the L3 performance event select register ThreadMask
bitfield, to enable per hardware thread accounting.

Signed-off-by: Kim Phillips <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Martin Liska <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Cc: Janakarajan Natarajan <[email protected]>
Cc: Gary Hook <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Vince Weaver <[email protected]>
Cc: [email protected]
---
RESEND3: file sent with header:

Content-Type: text/plain; charset="us-ascii"

to work around a bug in the Microsoft Outlook SMTP servers.

arch/x86/events/amd/uncore.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index c2c4ae5fbbfc..a6ea07f2aa84 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -202,15 +202,22 @@ static int amd_uncore_event_init(struct perf_event *event)
hwc->config = event->attr.config & AMD64_RAW_EVENT_MASK_NB;
hwc->idx = -1;

+ if (event->cpu < 0)
+ return -EINVAL;
+
/*
* SliceMask and ThreadMask need to be set for certain L3 events in
* Family 17h. For other events, the two fields do not affect the count.
*/
- if (l3_mask && is_llc_event(event))
- hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);
+ if (l3_mask && is_llc_event(event)) {
+ int thread = 2 * (cpu_data(event->cpu).cpu_core_id % 4);

- if (event->cpu < 0)
- return -EINVAL;
+ if (smp_num_siblings > 1)
+ thread += cpu_data(event->cpu).apicid & 1;
+
+ hwc->config |= (1ULL << (AMD64_L3_THREAD_SHIFT + thread) &
+ AMD64_L3_THREAD_MASK) | AMD64_L3_SLICE_MASK;
+ }

uncore = event_to_amd_uncore(event);
if (!uncore)
--
2.22.0

2019-07-01 08:32:21

by Peter Zijlstra

[permalink] [raw]
Subject: Re: [PATCH 1/2 RESEND3] perf/x86/amd/uncore: Do not set ThreadMask and SliceMask for non-L3 PMCs

On Fri, Jun 28, 2019 at 09:59:20PM +0000, Phillips, Kim wrote:
> From: Kim Phillips <[email protected]>
>
> Commit d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask
> for L3 Cache perf events") enables L3 PMC events for all threads and
> slices by writing 1s in ChL3PmcCfg (L3 PMC PERF_CTL) register fields.
>
> Those bitfields overlap with high order event select bits in the Data
> Fabric PMC control register, however.
>
> So when a user requests raw Data Fabric events (-e amd_df/event=0xYYY/),
> the two highest order bits get inadvertently set, changing the counter
> select to events that don't exist, and for which no counts are read.
>
> This patch changes the logic to write the L3 masks only when dealing
> with L3 PMC counters.
>
> AMD Family 16h and below Northbridge (NB) counters were not affected.


Thanks!

Subject: [tip:perf/urgent] perf/x86/amd/uncore: Do not set 'ThreadMask' and 'SliceMask' for non-L3 PMCs

Commit-ID: 16f4641166b10e199f0d7b68c2c5f004fef0bda3
Gitweb: https://git.kernel.org/tip/16f4641166b10e199f0d7b68c2c5f004fef0bda3
Author: Kim Phillips <[email protected]>
AuthorDate: Fri, 28 Jun 2019 21:59:20 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sat, 13 Jul 2019 11:21:26 +0200

perf/x86/amd/uncore: Do not set 'ThreadMask' and 'SliceMask' for non-L3 PMCs

The following commit:

d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events")

enables L3 PMC events for all threads and slices by writing 1's in
'ChL3PmcCfg' (L3 PMC PERF_CTL) register fields.

Those bitfields overlap with high order event select bits in the Data
Fabric PMC control register, however.

So when a user requests raw Data Fabric events (-e amd_df/event=0xYYY/),
the two highest order bits get inadvertently set, changing the counter
select to events that don't exist, and for which no counts are read.

This patch changes the logic to write the L3 masks only when dealing
with L3 PMC counters.

AMD Family 16h and below Northbridge (NB) counters were not affected.

Signed-off-by: Kim Phillips <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Gary Hook <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Janakarajan Natarajan <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Martin Liska <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Fixes: d7cbbe49a930 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events")
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/events/amd/uncore.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index 85e6984c560b..c2c4ae5fbbfc 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -206,7 +206,7 @@ static int amd_uncore_event_init(struct perf_event *event)
* SliceMask and ThreadMask need to be set for certain L3 events in
* Family 17h. For other events, the two fields do not affect the count.
*/
- if (l3_mask)
+ if (l3_mask && is_llc_event(event))
hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);

if (event->cpu < 0)

Subject: [tip:perf/urgent] perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs

Commit-ID: 2f217d58a8a086d3399fecce39fb358848e799c4
Gitweb: https://git.kernel.org/tip/2f217d58a8a086d3399fecce39fb358848e799c4
Author: Kim Phillips <[email protected]>
AuthorDate: Fri, 28 Jun 2019 21:59:33 +0000
Committer: Ingo Molnar <[email protected]>
CommitDate: Sat, 13 Jul 2019 11:21:27 +0200

perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs

Fill in the L3 performance event select register ThreadMask
bitfield, to enable per hardware thread accounting.

Signed-off-by: Kim Phillips <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Gary Hook <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Cc: Janakarajan Natarajan <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Martin Liska <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Pu Wen <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Suravee Suthikulpanit <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Vince Weaver <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
arch/x86/events/amd/uncore.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c
index c2c4ae5fbbfc..a6ea07f2aa84 100644
--- a/arch/x86/events/amd/uncore.c
+++ b/arch/x86/events/amd/uncore.c
@@ -202,15 +202,22 @@ static int amd_uncore_event_init(struct perf_event *event)
hwc->config = event->attr.config & AMD64_RAW_EVENT_MASK_NB;
hwc->idx = -1;

+ if (event->cpu < 0)
+ return -EINVAL;
+
/*
* SliceMask and ThreadMask need to be set for certain L3 events in
* Family 17h. For other events, the two fields do not affect the count.
*/
- if (l3_mask && is_llc_event(event))
- hwc->config |= (AMD64_L3_SLICE_MASK | AMD64_L3_THREAD_MASK);
+ if (l3_mask && is_llc_event(event)) {
+ int thread = 2 * (cpu_data(event->cpu).cpu_core_id % 4);

- if (event->cpu < 0)
- return -EINVAL;
+ if (smp_num_siblings > 1)
+ thread += cpu_data(event->cpu).apicid & 1;
+
+ hwc->config |= (1ULL << (AMD64_L3_THREAD_SHIFT + thread) &
+ AMD64_L3_THREAD_MASK) | AMD64_L3_SLICE_MASK;
+ }

uncore = event_to_amd_uncore(event);
if (!uncore)