[WIP] bench: benchmark per-CPU array/hashmap lookups

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
anakryiko · Apr 4, 2024 · 8dec900 · 8dec900
1 parent 8b06116
commit 8dec900
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diff --git a/tools/testing/selftests/bpf/bench.c b/tools/testing/selftests/bpf/bench.c
@@ -510,6 +510,10 @@ extern const struct bench bench_trig_fmodret;
 extern const struct bench bench_trig_tp;
 extern const struct bench bench_trig_rawtp;
 
+extern const struct bench bench_trig_arr_inc;
+extern const struct bench bench_trig_hash_inc;
+extern const struct bench bench_trig_glob_arr_inc;
+
 /* uprobe/uretprobe benchmarks */
 extern const struct bench bench_trig_uprobe_nop;
 extern const struct bench bench_trig_uretprobe_nop;
@@ -562,6 +566,11 @@ static const struct bench *benchs[] = {
 	&bench_trig_fmodret,
 	&bench_trig_tp,
 	&bench_trig_rawtp,
+
+	&bench_trig_arr_inc,
+	&bench_trig_hash_inc,
+	&bench_trig_glob_arr_inc,
+
 	/* uprobes */
 	&bench_trig_uprobe_nop,
 	&bench_trig_uretprobe_nop,

diff --git a/tools/testing/selftests/bpf/benchs/bench_trigger.c b/tools/testing/selftests/bpf/benchs/bench_trigger.c
@@ -225,6 +225,33 @@ static void trigger_fentry_setup(void)
 	attach_bpf(ctx.skel->progs.bench_trigger_fentry);
 }
 
+static void trigger_arr_inc_setup(void)
+{
+	setup_ctx();
+	bpf_program__set_autoload(ctx.skel->progs.trigger_driver, false);
+	bpf_program__set_autoload(ctx.skel->progs.trigger_arr_inc, true);
+	load_ctx();
+	ctx.driver_prog_fd = bpf_program__fd(ctx.skel->progs.trigger_arr_inc);
+}
+
+static void trigger_hash_inc_setup(void)
+{
+	setup_ctx();
+	bpf_program__set_autoload(ctx.skel->progs.trigger_driver, false);
+	bpf_program__set_autoload(ctx.skel->progs.trigger_hash_inc, true);
+	load_ctx();
+	ctx.driver_prog_fd = bpf_program__fd(ctx.skel->progs.trigger_hash_inc);
+}
+
+static void trigger_glob_arr_inc_setup(void)
+{
+	setup_ctx();
+	bpf_program__set_autoload(ctx.skel->progs.trigger_driver, false);
+	bpf_program__set_autoload(ctx.skel->progs.trigger_glob_arr_inc, true);
+	load_ctx();
+	ctx.driver_prog_fd = bpf_program__fd(ctx.skel->progs.trigger_glob_arr_inc);
+}
+
 static void trigger_fexit_setup(void)
 {
 	setup_ctx();
@@ -435,6 +462,10 @@ BENCH_TRIG_KERNEL(fmodret, "fmodret");
 BENCH_TRIG_KERNEL(tp, "tp");
 BENCH_TRIG_KERNEL(rawtp, "rawtp");
 
+BENCH_TRIG_KERNEL(arr_inc, "arr-inc");
+BENCH_TRIG_KERNEL(hash_inc, "hash-inc");
+BENCH_TRIG_KERNEL(glob_arr_inc, "glob-arr-inc");
+
 /* uprobe benchmarks */
 #define BENCH_TRIG_USERMODE(KIND, PRODUCER, NAME)			\
 const struct bench bench_trig_##KIND = {				\

diff --git a/tools/testing/selftests/bpf/progs/trigger_bench.c b/tools/testing/selftests/bpf/progs/trigger_bench.c
@@ -25,6 +25,50 @@ static __always_inline void inc_counter(void)
 	__sync_add_and_fetch(&hits[cpu & CPU_MASK].value, 1);
 }
 
+static __always_inline void inc_counter2(int amount)
+{
+	int cpu = bpf_get_smp_processor_id();
+
+	__sync_add_and_fetch(&hits[cpu & CPU_MASK].value, amount);
+}
+
+struct {
+        __uint(type, BPF_MAP_TYPE_PERCPU_HASH);
+        __type(key, int);
+        __type(value, int);
+        __uint(max_entries, 1);
+} hash_map SEC(".maps");
+
+struct {
+        __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
+        __type(key, int);
+        __type(value, int);
+        __uint(max_entries, 1);
+} array_map SEC(".maps");
+
+static int zero = 0;
+
+static void __always_inline hash_inc(void *map) {
+        int *p;
+
+        p = bpf_map_lookup_elem(map, &zero);
+        if (!p) {
+                bpf_map_update_elem(map, &zero, &zero, BPF_ANY);
+                p = bpf_map_lookup_elem(map, &zero);
+                if (!p)
+                        return;
+        }
+        *p += 1;
+}
+
+struct counter arr[256];
+
+static void __always_inline glob_arr_inc(void) {
+	int cpu = bpf_get_smp_processor_id();
+
+	arr[cpu].value += 1;
+}
+
 SEC("?uprobe")
 int bench_trigger_uprobe(void *ctx)
 {
@@ -34,6 +78,45 @@ int bench_trigger_uprobe(void *ctx)
 
 const volatile int batch_iters = 0;
 
+SEC("?raw_tp")
+int trigger_arr_inc(void *ctx)
+{
+	int i;
+
+	for (i = 0; i < batch_iters; i++)
+		hash_inc(&array_map);
+
+	inc_counter2(batch_iters);
+
+	return 0;
+}
+
+SEC("?raw_tp")
+int trigger_hash_inc(void *ctx)
+{
+	int i;
+
+	for (i = 0; i < batch_iters; i++)
+		hash_inc(&hash_map);
+
+	inc_counter2(batch_iters);
+
+	return 0;
+}
+
+SEC("?raw_tp")
+int trigger_glob_arr_inc(void *ctx)
+{
+	int i;
+
+	for (i = 0; i < batch_iters; i++)
+		glob_arr_inc();
+
+	inc_counter2(batch_iters);
+
+	return 0;
+}
+
 SEC("?raw_tp")
 int trigger_count(void *ctx)
 {