[PATCH V2 5/6] perf: Use sample_flags for data_src

From: kan . liang
Date: Thu Sep 01 2022 - 09:13:17 EST


From: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>

Use the new sample_flags to indicate whether the data_src field is
filled by the PMU driver.

Remove the data_src field from the perf_sample_data_init() to minimize
the number of cache lines touched.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
---
arch/powerpc/perf/core-book3s.c | 4 +++-
arch/x86/events/intel/ds.c | 8 ++++++--
include/linux/perf_event.h | 3 +--
kernel/events/core.c | 3 +++
4 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c
index a5c95a2006ea..6ec7069e6482 100644
--- a/arch/powerpc/perf/core-book3s.c
+++ b/arch/powerpc/perf/core-book3s.c
@@ -2301,8 +2301,10 @@ static void record_and_restart(struct perf_event *event, unsigned long val,
}

if (event->attr.sample_type & PERF_SAMPLE_DATA_SRC &&
- ppmu->get_mem_data_src)
+ ppmu->get_mem_data_src) {
ppmu->get_mem_data_src(&data.data_src, ppmu->flags, regs);
+ data.sample_flags |= PERF_SAMPLE_DATA_SRC;
+ }

if (event->attr.sample_type & PERF_SAMPLE_WEIGHT_TYPE &&
ppmu->get_mem_weight) {
diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index f66a4905cc87..985bbbab057f 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1543,8 +1543,10 @@ static void setup_pebs_fixed_sample_data(struct perf_event *event,
/*
* data.data_src encodes the data source
*/
- if (sample_type & PERF_SAMPLE_DATA_SRC)
+ if (sample_type & PERF_SAMPLE_DATA_SRC) {
data->data_src.val = get_data_src(event, pebs->dse);
+ data->sample_flags |= PERF_SAMPLE_DATA_SRC;
+ }

/*
* We must however always use iregs for the unwinder to stay sane; the
@@ -1778,8 +1780,10 @@ static void setup_pebs_adaptive_sample_data(struct perf_event *event,
data->sample_flags |= PERF_SAMPLE_WEIGHT_TYPE;
}

- if (sample_type & PERF_SAMPLE_DATA_SRC)
+ if (sample_type & PERF_SAMPLE_DATA_SRC) {
data->data_src.val = get_data_src(event, meminfo->aux);
+ data->sample_flags |= PERF_SAMPLE_DATA_SRC;
+ }

if (sample_type & PERF_SAMPLE_ADDR_TYPE)
data->addr = meminfo->address;
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 06a587b5faa9..6849f10dfc7e 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1013,7 +1013,6 @@ struct perf_sample_data {
struct perf_raw_record *raw;
u64 period;
u64 txn;
- union perf_mem_data_src data_src;

/*
* The other fields, optionally {set,used} by
@@ -1021,6 +1020,7 @@ struct perf_sample_data {
*/
struct perf_branch_stack *br_stack;
union perf_sample_weight weight;
+ union perf_mem_data_src data_src;

u64 type;
u64 ip;
@@ -1063,7 +1063,6 @@ static inline void perf_sample_data_init(struct perf_sample_data *data,
data->addr = addr;
data->raw = NULL;
data->period = period;
- data->data_src.val = PERF_MEM_NA;
data->txn = 0;
}

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f0af45db02b3..163e2f478e61 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7411,6 +7411,9 @@ void perf_prepare_sample(struct perf_event_header *header,
if (filtered_sample_type & PERF_SAMPLE_WEIGHT_TYPE)
data->weight.full = 0;

+ if (filtered_sample_type & PERF_SAMPLE_DATA_SRC)
+ data->data_src.val = PERF_MEM_NA;
+
if (sample_type & PERF_SAMPLE_REGS_INTR) {
/* regs dump ABI info */
int size = sizeof(u64);
--
2.35.1