[bpf-next v1] bpf: introduce stats update helper

[tong@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx]

From: Tonghao Zhang <tong@xxxxxxxxxxxxx>

This patch introduce a stats update helper to simplify codes.

Signed-off-by: Tonghao Zhang <tong@xxxxxxxxxxxxx>
Cc: Alexei Starovoitov <ast@xxxxxxxxxx>
Cc: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Cc: Andrii Nakryiko <andrii@xxxxxxxxxx>
Cc: Martin KaFai Lau <martin.lau@xxxxxxxxx>
Cc: Song Liu <song@xxxxxxxxxx>
Cc: Yonghong Song <yhs@xxxxxx>
Cc: John Fastabend <john.fastabend@xxxxxxxxx>
Cc: KP Singh <kpsingh@xxxxxxxxxx>
Cc: Stanislav Fomichev <sdf@xxxxxxxxxx>
Cc: Hao Luo <haoluo@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Hou Tao <houtao1@xxxxxxxxxx>
---
 include/linux/filter.h  | 22 +++++++++++++++-------
 kernel/bpf/trampoline.c | 10 +---------
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/include/linux/filter.h b/include/linux/filter.h
index 1727898f1641..582dfe1188e8 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -579,6 +579,20 @@ typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
 					  unsigned int (*bpf_func)(const void *,
 								   const struct bpf_insn *));
 
+static inline void bpf_prog_update_stats(const struct bpf_prog *prog, u64 start)
+{
+	struct bpf_prog_stats *stats;
+	unsigned long flags;
+
+	stats = this_cpu_ptr(prog->stats);
+	flags = u64_stats_update_begin_irqsave(&stats->syncp);
+
+	u64_stats_inc(&stats->cnt);
+	u64_stats_add(&stats->nsecs, sched_clock() - start);
+
+	u64_stats_update_end_irqrestore(&stats->syncp, flags);
+}
+
 static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
 					  const void *ctx,
 					  bpf_dispatcher_fn dfunc)
@@ -587,16 +601,10 @@ static __always_inline u32 __bpf_prog_run(const struct bpf_prog *prog,
 
 	cant_migrate();
 	if (static_branch_unlikely(&bpf_stats_enabled_key)) {
-		struct bpf_prog_stats *stats;
 		u64 start = sched_clock();
-		unsigned long flags;
 
 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
-		stats = this_cpu_ptr(prog->stats);
-		flags = u64_stats_update_begin_irqsave(&stats->syncp);
-		u64_stats_inc(&stats->cnt);
-		u64_stats_add(&stats->nsecs, sched_clock() - start);
-		u64_stats_update_end_irqrestore(&stats->syncp, flags);
+		bpf_prog_update_stats(prog, start);
 	} else {
 		ret = dfunc(ctx, prog->insnsi, prog->bpf_func);
 	}
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index d0ed7d6f5eec..07bc7c9a18d5 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -885,8 +885,6 @@ static u64 notrace __bpf_prog_enter_recur(struct bpf_prog *prog, struct bpf_tram
 static void notrace update_prog_stats(struct bpf_prog *prog,
 				      u64 start)
 {
-	struct bpf_prog_stats *stats;
-
 	if (static_branch_unlikely(&bpf_stats_enabled_key) &&
 	    /* static_key could be enabled in __bpf_prog_enter*
 	     * and disabled in __bpf_prog_exit*.
@@ -894,13 +892,7 @@ static void notrace update_prog_stats(struct bpf_prog *prog,
 	     * Hence check that 'start' is valid.
 	     */
 	    start > NO_START_TIME) {
-		unsigned long flags;
-
-		stats = this_cpu_ptr(prog->stats);
-		flags = u64_stats_update_begin_irqsave(&stats->syncp);
-		u64_stats_inc(&stats->cnt);
-		u64_stats_add(&stats->nsecs, sched_clock() - start);
-		u64_stats_update_end_irqrestore(&stats->syncp, flags);
+		bpf_prog_update_stats(prog, start);
 	}
 }
 
-- 
2.27.0