[PATCH 5/8] perf bpf filter: Add 'pid' sample data support

Namhyung Kim
2023-02-19T06:13:50Z

The pid is special because it's saved in the PERF_SAMPLE_TID together.
So it needs to differenciate tid and pid using the 'part' field in the
perf bpf filter entry struct.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
tools/perf/util/bpf-filter.c | 4 +++-
tools/perf/util/bpf-filter.h | 3 ++-
tools/perf/util/bpf-filter.l | 11 ++++++++++-
tools/perf/util/bpf-filter.y | 7 +++++--
tools/perf/util/bpf_skel/sample-filter.h | 3 ++-
tools/perf/util/bpf_skel/sample_filter.bpf.c | 5 ++++-
6 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/tools/perf/util/bpf-filter.c b/tools/perf/util/bpf-filter.c
index 11fb391c92e9..2e02dc965dd9 100644
--- a/tools/perf/util/bpf-filter.c
+++ b/tools/perf/util/bpf-filter.c
@@ -43,6 +43,7 @@ int perf_bpf_filter__prepare(struct evsel *evsel)
list_for_each_entry(expr, &evsel->bpf_filters, list) {
struct perf_bpf_filter_entry entry = {
.op = expr->op,
+ .part = expr->part,
.flags = expr->sample_flags,
.value = expr->val,
};
@@ -83,7 +84,7 @@ u64 perf_bpf_filter__lost_count(struct evsel *evsel)
return skel ? skel->bss->dropped : 0;
}

-struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags,
+struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags, int part,
enum perf_bpf_filter_op op,
unsigned long val)
{
@@ -92,6 +93,7 @@ struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flag
expr = malloc(sizeof(*expr));
if (expr != NULL) {
expr->sample_flags = sample_flags;
+ expr->part = part;
expr->op = op;
expr->val = val;
}
diff --git a/tools/perf/util/bpf-filter.h b/tools/perf/util/bpf-filter.h
index 36b44c8188ab..4fb33d296d9c 100644
--- a/tools/perf/util/bpf-filter.h
+++ b/tools/perf/util/bpf-filter.h
@@ -9,6 +9,7 @@
struct perf_bpf_filter_expr {
struct list_head list;
enum perf_bpf_filter_op op;
+ int part;
unsigned long sample_flags;
unsigned long val;
};
@@ -16,7 +17,7 @@ struct perf_bpf_filter_expr {
struct evsel;

#ifdef HAVE_BPF_SKEL
-struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags,
+struct perf_bpf_filter_expr *perf_bpf_filter_expr__new(unsigned long sample_flags, int part,
enum perf_bpf_filter_op op,
unsigned long val);
int perf_bpf_filter__parse(struct list_head *expr_head, const char *str);
diff --git a/tools/perf/util/bpf-filter.l b/tools/perf/util/bpf-filter.l
index 34c6a9fd4fa4..5117c76c7c7a 100644
--- a/tools/perf/util/bpf-filter.l
+++ b/tools/perf/util/bpf-filter.l
@@ -10,7 +10,15 @@

static int sample(unsigned long sample_flag)
{
- perf_bpf_filter_lval.sample = sample_flag;
+ perf_bpf_filter_lval.sample.type = sample_flag;
+ perf_bpf_filter_lval.sample.part = 0;
+ return BFT_SAMPLE;
+}
+
+static int sample_part(unsigned long sample_flag, int part)
+{
+ perf_bpf_filter_lval.sample.type = sample_flag;
+ perf_bpf_filter_lval.sample.part = part;
return BFT_SAMPLE;
}

@@ -46,6 +54,7 @@ num_hex 0[Xx][0-9a-fA-F]+
ip { return sample(PERF_SAMPLE_IP); }
id { return sample(PERF_SAMPLE_ID); }
tid { return sample(PERF_SAMPLE_TID); }
+pid { return sample_part(PERF_SAMPLE_TID, 1); }
cpu { return sample(PERF_SAMPLE_CPU); }
time { return sample(PERF_SAMPLE_TIME); }
addr { return sample(PERF_SAMPLE_ADDR); }
diff --git a/tools/perf/util/bpf-filter.y b/tools/perf/util/bpf-filter.y
index 510e944a6fa2..0c6035937a6e 100644
--- a/tools/perf/util/bpf-filter.y
+++ b/tools/perf/util/bpf-filter.y
@@ -19,7 +19,10 @@ static void perf_bpf_filter_error(struct list_head *expr __maybe_unused,
%union
{
unsigned long num;
- unsigned long sample;
+ struct {
+ unsigned long type;
+ int part;
+ } sample;
enum perf_bpf_filter_op op;
struct perf_bpf_filter_expr *expr;
}
@@ -47,7 +50,7 @@ filter_term
filter_term:
BFT_SAMPLE BFT_OP BFT_NUM
{
- $$ = perf_bpf_filter_expr__new($1, $2, $3);
+ $$ = perf_bpf_filter_expr__new($1.type, $1.part, $2, $3);
}

%%
diff --git a/tools/perf/util/bpf_skel/sample-filter.h b/tools/perf/util/bpf_skel/sample-filter.h
index 862060bfda14..6b9fd554ad7b 100644
--- a/tools/perf/util/bpf_skel/sample-filter.h
+++ b/tools/perf/util/bpf_skel/sample-filter.h
@@ -17,7 +17,8 @@ enum perf_bpf_filter_op {
/* BPF map entry for filtering */
struct perf_bpf_filter_entry {
enum perf_bpf_filter_op op;
- __u64 flags;
+ __u32 part; /* sub-sample type info when it has multiple values */
+ __u64 flags; /* perf sample type flags */
__u64 value;
};

diff --git a/tools/perf/util/bpf_skel/sample_filter.bpf.c b/tools/perf/util/bpf_skel/sample_filter.bpf.c
index 1aa6a4cacd51..e9a0633d638d 100644
--- a/tools/perf/util/bpf_skel/sample_filter.bpf.c
+++ b/tools/perf/util/bpf_skel/sample_filter.bpf.c
@@ -32,7 +32,10 @@ static inline __u64 perf_get_sample(struct bpf_perf_event_data_kern *kctx,
case PERF_SAMPLE_ID:
return kctx->data->id;
case PERF_SAMPLE_TID:
- return kctx->data->tid_entry.tid;
+ if (entry->part)
+ return kctx->data->tid_entry.pid;
+ else
+ return kctx->data->tid_entry.tid;
case PERF_SAMPLE_CPU:
return kctx->data->cpu_entry.cpu;
case PERF_SAMPLE_TIME:
--
2.39.2.637.g21b0678d19-goog