// SPDX-License-Identifier: GPL-2.0/* Copyright (C) 2022. Huawei Technologies Co., Ltd */#define _GNU_SOURCE#include <sched.h>#include <unistd.h>#include <stdlib.h>#include <stdbool.h>#include <errno.h>#include <string.h>#include <pthread.h> #include <bpf/bpf.h>#include <bpf/libbpf.h> #include "bpf_util.h"#include "test_maps.h"#include "task_local_storage_helpers.h"#include "read_bpf_task_storage_busy.skel.h" struct lookup_ctx {	bool start;	bool stop;	int pid_fd;	int map_fd;	int loop;}; static void *lookup_fn(void *arg){	struct lookup_ctx *ctx = arg;	long value;	int i = 0; 	while (!ctx->start)		usleep(1); 	while (!ctx->stop && i++ < ctx->loop)		bpf_map_lookup_elem(ctx->map_fd, &ctx->pid_fd, &value);	return NULL;} static void abort_lookup(struct lookup_ctx *ctx, pthread_t *tids, unsigned int nr){	unsigned int i; 	ctx->stop = true;	ctx->start = true;	for (i = 0; i < nr; i++)		pthread_join(tids[i], NULL);} void test_task_storage_map_stress_lookup(void){#define MAX_NR_THREAD 4096	unsigned int i, nr = 256, loop = 8192, cpu = 0;	struct read_bpf_task_storage_busy *skel;	pthread_t tids[MAX_NR_THREAD];	struct lookup_ctx ctx;	cpu_set_t old, new;	const char *cfg;	int err; 	cfg = getenv("TASK_STORAGE_MAP_NR_THREAD");	if (cfg) {		nr = atoi(cfg);		if (nr > MAX_NR_THREAD)			nr = MAX_NR_THREAD;	}	cfg = getenv("TASK_STORAGE_MAP_NR_LOOP");	if (cfg)		loop = atoi(cfg);	cfg = getenv("TASK_STORAGE_MAP_PIN_CPU");	if (cfg)		cpu = atoi(cfg); 	skel = read_bpf_task_storage_busy__open_and_load();	err = libbpf_get_error(skel);	CHECK(err, "open_and_load", "error %d\n", err); 	/* Only for a fully preemptible kernel */	if (!skel->kconfig->CONFIG_PREEMPTION) {		printf("%s SKIP (no CONFIG_PREEMPTION)\n", __func__);		read_bpf_task_storage_busy__destroy(skel);		skips++;		return;	} 	/* Save the old affinity setting */	sched_getaffinity(getpid(), sizeof(old), &old); 	/* Pinned on a specific CPU */	CPU_ZERO(&new);	CPU_SET(cpu, &new);	sched_setaffinity(getpid(), sizeof(new), &new); 	ctx.start = false;	ctx.stop = false;	ctx.pid_fd = sys_pidfd_open(getpid(), 0);	ctx.map_fd = bpf_map__fd(skel->maps.task);	ctx.loop = loop;	for (i = 0; i < nr; i++) {		err = pthread_create(&tids[i], NULL, lookup_fn, &ctx);		if (err) {			abort_lookup(&ctx, tids, i);			CHECK(err, "pthread_create", "error %d\n", err);			goto out;		}	} 	ctx.start = true;	for (i = 0; i < nr; i++)		pthread_join(tids[i], NULL); 	skel->bss->pid = getpid();	err = read_bpf_task_storage_busy__attach(skel);	CHECK(err, "attach", "error %d\n", err); 	/* Trigger program */	sys_gettid();	skel->bss->pid = 0; 	CHECK(skel->bss->busy != 0, "bad bpf_task_storage_busy", "got %d\n", skel->bss->busy);out:	read_bpf_task_storage_busy__destroy(skel);	/* Restore affinity setting */	sched_setaffinity(getpid(), sizeof(old), &old);	printf("%s:PASS\n", __func__);}