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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2020 Facebook */
#define _GNU_SOURCE
#include <unistd.h>
#include "bench.h"
#include "trigger_bench.skel.h"
#include "trace_helpers.h"
/* adjust slot shift in inc_hits() if changing */
#define MAX_BUCKETS 256
#pragma GCC diagnostic ignored "-Wattributes"
/* BPF triggering benchmarks */
static struct trigger_ctx {
struct trigger_bench *skel;
} ctx;
static struct counter base_hits[MAX_BUCKETS];
static __always_inline void inc_counter(struct counter *counters)
{
static __thread int tid = 0;
unsigned slot;
if (unlikely(tid == 0))
tid = syscall(SYS_gettid);
/* multiplicative hashing, it's fast */
slot = 2654435769U * tid;
slot >>= 24;
atomic_inc(&base_hits[slot].value); /* use highest byte as an index */
}
static long sum_and_reset_counters(struct counter *counters)
{
int i;
long sum = 0;
for (i = 0; i < MAX_BUCKETS; i++)
sum += atomic_swap(&counters[i].value, 0);
return sum;
}
static void trigger_validate(void)
{
if (env.consumer_cnt != 0) {
fprintf(stderr, "benchmark doesn't support consumer!\n");
exit(1);
}
}
static void *trigger_base_producer(void *input)
{
while (true) {
(void)syscall(__NR_getpgid);
inc_counter(base_hits);
}
return NULL;
}
static void trigger_base_measure(struct bench_res *res)
{
res->hits = sum_and_reset_counters(base_hits);
}
static void *trigger_producer(void *input)
{
while (true)
(void)syscall(__NR_getpgid);
return NULL;
}
static void trigger_measure(struct bench_res *res)
{
res->hits = sum_and_reset_counters(ctx.skel->bss->hits);
}
static void setup_ctx(void)
{
setup_libbpf();
ctx.skel = trigger_bench__open_and_load();
if (!ctx.skel) {
fprintf(stderr, "failed to open skeleton\n");
exit(1);
}
}
static void attach_bpf(struct bpf_program *prog)
{
struct bpf_link *link;
link = bpf_program__attach(prog);
if (!link) {
fprintf(stderr, "failed to attach program!\n");
exit(1);
}
}
static void trigger_tp_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_tp);
}
static void trigger_rawtp_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_raw_tp);
}
static void trigger_kprobe_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_kprobe);
}
static void trigger_kretprobe_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_kretprobe);
}
static void trigger_kprobe_multi_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_kprobe_multi);
}
static void trigger_kretprobe_multi_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_kretprobe_multi);
}
static void trigger_fentry_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_fentry);
}
static void trigger_fexit_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_fexit);
}
static void trigger_fentry_sleep_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_fentry_sleep);
}
static void trigger_fmodret_setup(void)
{
setup_ctx();
attach_bpf(ctx.skel->progs.bench_trigger_fmodret);
}
/* 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.
*/
__nocf_check __weak void uprobe_target_nop(void)
{
asm volatile ("nop");
}
__weak void opaque_noop_func(void)
{
}
__nocf_check __weak int uprobe_target_push(void)
{
/* overhead of function call is negligible compared to uprobe
* triggering, so this shouldn't affect benchmark results much
*/
opaque_noop_func();
return 1;
}
__nocf_check __weak void uprobe_target_ret(void)
{
asm volatile ("");
}
static void *uprobe_base_producer(void *input)
{
while (true) {
uprobe_target_nop();
inc_counter(base_hits);
}
return NULL;
}
static void *uprobe_producer_nop(void *input)
{
while (true)
uprobe_target_nop();
return NULL;
}
static void *uprobe_producer_push(void *input)
{
while (true)
uprobe_target_push();
return NULL;
}
static void *uprobe_producer_ret(void *input)
{
while (true)
uprobe_target_ret();
return NULL;
}
static void usetup(bool use_retprobe, void *target_addr)
{
size_t uprobe_offset;
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);
}
uprobe_offset = get_uprobe_offset(target_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_nop(void)
{
usetup(false, &uprobe_target_nop);
}
static void uretprobe_setup_nop(void)
{
usetup(true, &uprobe_target_nop);
}
static void uprobe_setup_push(void)
{
usetup(false, &uprobe_target_push);
}
static void uretprobe_setup_push(void)
{
usetup(true, &uprobe_target_push);
}
static void uprobe_setup_ret(void)
{
usetup(false, &uprobe_target_ret);
}
static void uretprobe_setup_ret(void)
{
usetup(true, &uprobe_target_ret);
}
const struct bench bench_trig_base = {
.name = "trig-base",
.validate = trigger_validate,
.producer_thread = trigger_base_producer,
.measure = trigger_base_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_tp = {
.name = "trig-tp",
.validate = trigger_validate,
.setup = trigger_tp_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_rawtp = {
.name = "trig-rawtp",
.validate = trigger_validate,
.setup = trigger_rawtp_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_kprobe = {
.name = "trig-kprobe",
.validate = trigger_validate,
.setup = trigger_kprobe_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_kretprobe = {
.name = "trig-kretprobe",
.validate = trigger_validate,
.setup = trigger_kretprobe_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_kprobe_multi = {
.name = "trig-kprobe-multi",
.validate = trigger_validate,
.setup = trigger_kprobe_multi_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_kretprobe_multi = {
.name = "trig-kretprobe-multi",
.validate = trigger_validate,
.setup = trigger_kretprobe_multi_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_fentry = {
.name = "trig-fentry",
.validate = trigger_validate,
.setup = trigger_fentry_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_fexit = {
.name = "trig-fexit",
.validate = trigger_validate,
.setup = trigger_fexit_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_fentry_sleep = {
.name = "trig-fentry-sleep",
.validate = trigger_validate,
.setup = trigger_fentry_sleep_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_fmodret = {
.name = "trig-fmodret",
.validate = trigger_validate,
.setup = trigger_fmodret_setup,
.producer_thread = trigger_producer,
.measure = trigger_measure,
.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,
.measure = trigger_base_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uprobe_nop = {
.name = "trig-uprobe-nop",
.setup = uprobe_setup_nop,
.producer_thread = uprobe_producer_nop,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uretprobe_nop = {
.name = "trig-uretprobe-nop",
.setup = uretprobe_setup_nop,
.producer_thread = uprobe_producer_nop,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uprobe_push = {
.name = "trig-uprobe-push",
.setup = uprobe_setup_push,
.producer_thread = uprobe_producer_push,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uretprobe_push = {
.name = "trig-uretprobe-push",
.setup = uretprobe_setup_push,
.producer_thread = uprobe_producer_push,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uprobe_ret = {
.name = "trig-uprobe-ret",
.setup = uprobe_setup_ret,
.producer_thread = uprobe_producer_ret,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
const struct bench bench_trig_uretprobe_ret = {
.name = "trig-uretprobe-ret",
.setup = uretprobe_setup_ret,
.producer_thread = uprobe_producer_ret,
.measure = trigger_measure,
.report_progress = hits_drops_report_progress,
.report_final = hits_drops_report_final,
};
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