diff options
Diffstat (limited to 'tools/testing/selftests/bpf/benchs/bench_trigger.c')
| -rw-r--r-- | tools/testing/selftests/bpf/benchs/bench_trigger.c | 162 |
1 files changed, 154 insertions, 8 deletions
diff --git a/tools/testing/selftests/bpf/benchs/bench_trigger.c b/tools/testing/selftests/bpf/benchs/bench_trigger.c index f41a491a8cc0..7f957c55a3ca 100644 --- a/tools/testing/selftests/bpf/benchs/bench_trigger.c +++ b/tools/testing/selftests/bpf/benchs/bench_trigger.c @@ -2,6 +2,7 @@ /* Copyright (c) 2020 Facebook */ #include "bench.h" #include "trigger_bench.skel.h" +#include "trace_helpers.h" /* BPF triggering benchmarks */ static struct trigger_ctx { @@ -10,7 +11,7 @@ static struct trigger_ctx { static struct counter base_hits; -static void trigger_validate() +static void trigger_validate(void) { if (env.consumer_cnt != 1) { fprintf(stderr, "benchmark doesn't support multi-consumer!\n"); @@ -44,7 +45,7 @@ static void trigger_measure(struct bench_res *res) res->hits = atomic_swap(&ctx.skel->bss->hits, 0); } -static void setup_ctx() +static void setup_ctx(void) { setup_libbpf(); @@ -66,37 +67,37 @@ static void attach_bpf(struct bpf_program *prog) } } -static void trigger_tp_setup() +static void trigger_tp_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_tp); } -static void trigger_rawtp_setup() +static void trigger_rawtp_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_raw_tp); } -static void trigger_kprobe_setup() +static void trigger_kprobe_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_kprobe); } -static void trigger_fentry_setup() +static void trigger_fentry_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_fentry); } -static void trigger_fentry_sleep_setup() +static void trigger_fentry_sleep_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_fentry_sleep); } -static void trigger_fmodret_setup() +static void trigger_fmodret_setup(void) { setup_ctx(); attach_bpf(ctx.skel->progs.bench_trigger_fmodret); @@ -107,6 +108,101 @@ static void *trigger_consumer(void *input) return NULL; } +/* make sure call is not inlined and not avoided by compiler, so __weak and + * inline asm volatile in the body of the function + * + * There is a performance difference between uprobing at nop location vs other + * instructions. So use two different targets, one of which starts with nop + * and another doesn't. + * + * GCC doesn't generate stack setup preample for these functions due to them + * having no input arguments and doing nothing in the body. + */ +__weak void uprobe_target_with_nop(void) +{ + asm volatile ("nop"); +} + +__weak void uprobe_target_without_nop(void) +{ + asm volatile (""); +} + +static void *uprobe_base_producer(void *input) +{ + while (true) { + uprobe_target_with_nop(); + atomic_inc(&base_hits.value); + } + return NULL; +} + +static void *uprobe_producer_with_nop(void *input) +{ + while (true) + uprobe_target_with_nop(); + return NULL; +} + +static void *uprobe_producer_without_nop(void *input) +{ + while (true) + uprobe_target_without_nop(); + return NULL; +} + +static void usetup(bool use_retprobe, bool use_nop) +{ + size_t uprobe_offset; + ssize_t base_addr; + struct bpf_link *link; + + setup_libbpf(); + + ctx.skel = trigger_bench__open_and_load(); + if (!ctx.skel) { + fprintf(stderr, "failed to open skeleton\n"); + exit(1); + } + + base_addr = get_base_addr(); + if (use_nop) + uprobe_offset = get_uprobe_offset(&uprobe_target_with_nop, base_addr); + else + uprobe_offset = get_uprobe_offset(&uprobe_target_without_nop, base_addr); + + link = bpf_program__attach_uprobe(ctx.skel->progs.bench_trigger_uprobe, + use_retprobe, + -1 /* all PIDs */, + "/proc/self/exe", + uprobe_offset); + if (!link) { + fprintf(stderr, "failed to attach uprobe!\n"); + exit(1); + } + ctx.skel->links.bench_trigger_uprobe = link; +} + +static void uprobe_setup_with_nop(void) +{ + usetup(false, true); +} + +static void uretprobe_setup_with_nop(void) +{ + usetup(true, true); +} + +static void uprobe_setup_without_nop(void) +{ + usetup(false, false); +} + +static void uretprobe_setup_without_nop(void) +{ + usetup(true, false); +} + const struct bench bench_trig_base = { .name = "trig-base", .validate = trigger_validate, @@ -182,3 +278,53 @@ const struct bench bench_trig_fmodret = { .report_progress = hits_drops_report_progress, .report_final = hits_drops_report_final, }; + +const struct bench bench_trig_uprobe_base = { + .name = "trig-uprobe-base", + .setup = NULL, /* no uprobe/uretprobe is attached */ + .producer_thread = uprobe_base_producer, + .consumer_thread = trigger_consumer, + .measure = trigger_base_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; + +const struct bench bench_trig_uprobe_with_nop = { + .name = "trig-uprobe-with-nop", + .setup = uprobe_setup_with_nop, + .producer_thread = uprobe_producer_with_nop, + .consumer_thread = trigger_consumer, + .measure = trigger_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; + +const struct bench bench_trig_uretprobe_with_nop = { + .name = "trig-uretprobe-with-nop", + .setup = uretprobe_setup_with_nop, + .producer_thread = uprobe_producer_with_nop, + .consumer_thread = trigger_consumer, + .measure = trigger_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; + +const struct bench bench_trig_uprobe_without_nop = { + .name = "trig-uprobe-without-nop", + .setup = uprobe_setup_without_nop, + .producer_thread = uprobe_producer_without_nop, + .consumer_thread = trigger_consumer, + .measure = trigger_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; + +const struct bench bench_trig_uretprobe_without_nop = { + .name = "trig-uretprobe-without-nop", + .setup = uretprobe_setup_without_nop, + .producer_thread = uprobe_producer_without_nop, + .consumer_thread = trigger_consumer, + .measure = trigger_measure, + .report_progress = hits_drops_report_progress, + .report_final = hits_drops_report_final, +}; |