[PATCHv2,RFC,bpf-next,1/7] bpf: Move bpf_prog_start/end functions to generic place

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 6428634da57e..90cd58520bd4 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -4494,3 +4494,100 @@  SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz
 
 	return err;
 }
+
+#define NO_START_TIME 1
+static u64 notrace bpf_prog_start_time(void)
+{
+	u64 start = NO_START_TIME;
+
+	if (static_branch_unlikely(&bpf_stats_enabled_key)) {
+		start = sched_clock();
+		if (unlikely(!start))
+			start = NO_START_TIME;
+	}
+	return start;
+}
+
+static void notrace inc_misses_counter(struct bpf_prog *prog)
+{
+	struct bpf_prog_stats *stats;
+
+	stats = this_cpu_ptr(prog->stats);
+	u64_stats_update_begin(&stats->syncp);
+	stats->misses++;
+	u64_stats_update_end(&stats->syncp);
+}
+
+/* The logic is similar to BPF_PROG_RUN, but with an explicit
+ * rcu_read_lock() and migrate_disable() which are required
+ * for the trampoline. The macro is split into
+ * call __bpf_prog_enter
+ * call prog->bpf_func
+ * call __bpf_prog_exit
+ *
+ * __bpf_prog_enter returns:
+ * 0 - skip execution of the bpf prog
+ * 1 - execute bpf prog
+ * [2..MAX_U64] - excute bpf prog and record execution time.
+ *     This is start time.
+ */
+u64 notrace __bpf_prog_enter(struct bpf_prog *prog)
+	__acquires(RCU)
+{
+	rcu_read_lock();
+	migrate_disable();
+	if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
+		inc_misses_counter(prog);
+		return 0;
+	}
+	return bpf_prog_start_time();
+}
+
+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*.
+	     * And vice versa.
+	     * Hence check that 'start' is valid.
+	     */
+	    start > NO_START_TIME) {
+		stats = this_cpu_ptr(prog->stats);
+		u64_stats_update_begin(&stats->syncp);
+		stats->cnt++;
+		stats->nsecs += sched_clock() - start;
+		u64_stats_update_end(&stats->syncp);
+	}
+}
+
+void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start)
+	__releases(RCU)
+{
+	update_prog_stats(prog, start);
+	__this_cpu_dec(*(prog->active));
+	migrate_enable();
+	rcu_read_unlock();
+}
+
+u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog)
+{
+	rcu_read_lock_trace();
+	migrate_disable();
+	might_fault();
+	if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
+		inc_misses_counter(prog);
+		return 0;
+	}
+	return bpf_prog_start_time();
+}
+
+void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start)
+{
+	update_prog_stats(prog, start);
+	__this_cpu_dec(*(prog->active));
+	migrate_enable();
+	rcu_read_unlock_trace();
+}
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 1f3a4be4b175..951cad26c5a9 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -489,103 +489,6 @@  void bpf_trampoline_put(struct bpf_trampoline *tr)
 	mutex_unlock(&trampoline_mutex);
 }
 
-#define NO_START_TIME 1
-static u64 notrace bpf_prog_start_time(void)
-{
-	u64 start = NO_START_TIME;
-
-	if (static_branch_unlikely(&bpf_stats_enabled_key)) {
-		start = sched_clock();
-		if (unlikely(!start))
-			start = NO_START_TIME;
-	}
-	return start;
-}
-
-static void notrace inc_misses_counter(struct bpf_prog *prog)
-{
-	struct bpf_prog_stats *stats;
-
-	stats = this_cpu_ptr(prog->stats);
-	u64_stats_update_begin(&stats->syncp);
-	stats->misses++;
-	u64_stats_update_end(&stats->syncp);
-}
-
-/* The logic is similar to BPF_PROG_RUN, but with an explicit
- * rcu_read_lock() and migrate_disable() which are required
- * for the trampoline. The macro is split into
- * call __bpf_prog_enter
- * call prog->bpf_func
- * call __bpf_prog_exit
- *
- * __bpf_prog_enter returns:
- * 0 - skip execution of the bpf prog
- * 1 - execute bpf prog
- * [2..MAX_U64] - excute bpf prog and record execution time.
- *     This is start time.
- */
-u64 notrace __bpf_prog_enter(struct bpf_prog *prog)
-	__acquires(RCU)
-{
-	rcu_read_lock();
-	migrate_disable();
-	if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
-		inc_misses_counter(prog);
-		return 0;
-	}
-	return bpf_prog_start_time();
-}
-
-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*.
-	     * And vice versa.
-	     * Hence check that 'start' is valid.
-	     */
-	    start > NO_START_TIME) {
-		stats = this_cpu_ptr(prog->stats);
-		u64_stats_update_begin(&stats->syncp);
-		stats->cnt++;
-		stats->nsecs += sched_clock() - start;
-		u64_stats_update_end(&stats->syncp);
-	}
-}
-
-void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start)
-	__releases(RCU)
-{
-	update_prog_stats(prog, start);
-	__this_cpu_dec(*(prog->active));
-	migrate_enable();
-	rcu_read_unlock();
-}
-
-u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog)
-{
-	rcu_read_lock_trace();
-	migrate_disable();
-	might_fault();
-	if (unlikely(__this_cpu_inc_return(*(prog->active)) != 1)) {
-		inc_misses_counter(prog);
-		return 0;
-	}
-	return bpf_prog_start_time();
-}
-
-void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start)
-{
-	update_prog_stats(prog, start);
-	__this_cpu_dec(*(prog->active));
-	migrate_enable();
-	rcu_read_unlock_trace();
-}
-
 void notrace __bpf_tramp_enter(struct bpf_tramp_image *tr)
 {
 	percpu_ref_get(&tr->pcref);