--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Use the core scheduling prctl() to test core scheduling cookies control.
+ *
+ * Copyright (c) 2021 Oracle and/or its affiliates.
+ * Author: Chris Hyser <chris.hyser@oracle.com>
+ *
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses>.
+ */
+
+#define _GNU_SOURCE
+#include <sys/eventfd.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <sys/prctl.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <time.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if __GLIBC_PREREQ(2, 30) == 0
+#include <sys/syscall.h>
+static pid_t gettid(void)
+{
+ return syscall(SYS_gettid);
+}
+#endif
+
+#ifndef PR_SCHED_CORE
+#define PR_SCHED_CORE 62
+# define PR_SCHED_CORE_GET 0
+# define PR_SCHED_CORE_CREATE 1 /* create unique core_sched cookie */
+# define PR_SCHED_CORE_SHARE_TO 2 /* push core_sched cookie to pid */
+# define PR_SCHED_CORE_SHARE_FROM 3 /* pull core_sched cookie to pid */
+# define PR_SCHED_CORE_MAX 4
+#endif
+
+#define MAX_PROCESSES 128
+#define MAX_THREADS 128
+
+static const char USAGE[] = "cs_prctl_test [options]\n"
+" options:\n"
+" -P : number of processes to create.\n"
+" -T : number of threads per process to create.\n"
+" -d : delay time to keep tasks alive.\n"
+" -k : keep tasks alive until keypress.\n";
+
+enum pid_type {PIDTYPE_PID = 0, PIDTYPE_TGID, PIDTYPE_PGID};
+
+const int THREAD_CLONE_FLAGS = CLONE_THREAD | CLONE_SIGHAND | CLONE_FS | CLONE_VM | CLONE_FILES;
+
+static int _prctl(int option, unsigned long arg2, unsigned long arg3, unsigned long arg4,
+ unsigned long arg5)
+{
+ int res;
+
+ res = prctl(option, arg2, arg3, arg4, arg5);
+ printf("%d = prctl(%d, %ld, %ld, %ld, %lx)\n", res, option, (long)arg2, (long)arg3,
+ (long)arg4, arg5);
+ return res;
+}
+
+#define STACK_SIZE (1024 * 1024)
+
+#define handle_error(msg) __handle_error(__FILE__, __LINE__, msg)
+static void __handle_error(char *fn, int ln, char *msg)
+{
+ printf("(%s:%d) - ", fn, ln);
+ perror(msg);
+ exit(EXIT_FAILURE);
+}
+
+static void handle_usage(int rc, char *msg)
+{
+ puts(USAGE);
+ puts(msg);
+ putchar('\n');
+ exit(rc);
+}
+
+static unsigned long get_cs_cookie(int pid)
+{
+ unsigned long long cookie;
+ int ret;
+
+ ret = prctl(PR_SCHED_CORE, PR_SCHED_CORE_GET, pid, PIDTYPE_PID,
+ (unsigned long)&cookie);
+ if (ret) {
+ printf("Not a core sched system\n");
+ return -1UL;
+ }
+
+ return cookie;
+}
+
+struct child_args {
+ int num_threads;
+ int pfd[2];
+ int cpid;
+ int thr_tids[MAX_THREADS];
+};
+
+static int child_func_thread(void __attribute__((unused))*arg)
+{
+ while (1)
+ usleep(20000);
+ return 0;
+}
+
+static void create_threads(int num_threads, int thr_tids[])
+{
+ void *child_stack;
+ pid_t tid;
+ int i;
+
+ for (i = 0; i < num_threads; ++i) {
+ child_stack = malloc(STACK_SIZE);
+ if (!child_stack)
+ handle_error("child stack allocate");
+
+ tid = clone(child_func_thread, child_stack + STACK_SIZE, THREAD_CLONE_FLAGS, NULL);
+ if (tid == -1)
+ handle_error("clone thread");
+ thr_tids[i] = tid;
+ }
+}
+
+static int child_func_process(void *arg)
+{
+ struct child_args *ca = (struct child_args *)arg;
+
+ close(ca->pfd[0]);
+
+ create_threads(ca->num_threads, ca->thr_tids);
+
+ write(ca->pfd[1], &ca->thr_tids, sizeof(int) * ca->num_threads);
+ close(ca->pfd[1]);
+
+ while (1)
+ usleep(20000);
+ return 0;
+}
+
+static unsigned char child_func_process_stack[STACK_SIZE];
+
+void create_processes(int num_processes, int num_threads, struct child_args proc[])
+{
+ pid_t cpid;
+ int i;
+
+ for (i = 0; i < num_processes; ++i) {
+ proc[i].num_threads = num_threads;
+
+ if (pipe(proc[i].pfd) == -1)
+ handle_error("pipe() failed");
+
+ cpid = clone(child_func_process, child_func_process_stack + STACK_SIZE,
+ SIGCHLD, &proc[i]);
+ proc[i].cpid = cpid;
+ close(proc[i].pfd[1]);
+ }
+
+ for (i = 0; i < num_processes; ++i) {
+ read(proc[i].pfd[0], &proc[i].thr_tids, sizeof(int) * proc[i].num_threads);
+ close(proc[i].pfd[0]);
+ }
+}
+
+void disp_processes(int num_processes, struct child_args proc[])
+{
+ int i, j;
+
+ printf("tid=%d, / tgid=%d / pgid=%d: %lx\n", gettid(), getpid(), getpgid(0),
+ get_cs_cookie(getpid()));
+
+ for (i = 0; i < num_processes; ++i) {
+ printf(" tid=%d, / tgid=%d / pgid=%d: %lx\n", proc[i].cpid, proc[i].cpid,
+ getpgid(proc[i].cpid), get_cs_cookie(proc[i].cpid));
+ for (j = 0; j < proc[i].num_threads; ++j) {
+ printf(" tid=%d, / tgid=%d / pgid=%d: %lx\n", proc[i].thr_tids[j],
+ proc[i].cpid, getpgid(0), get_cs_cookie(proc[i].thr_tids[j]));
+ }
+ }
+ puts("\n");
+}
+
+static int errors;
+
+#define validate(v) _validate(__LINE__, v, #v)
+void _validate(int line, int val, char *msg)
+{
+ if (!val) {
+ ++errors;
+ printf("(%d) FAILED: %s\n", line, msg);
+ } else {
+ printf("(%d) PASSED: %s\n", line, msg);
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ struct child_args procs[MAX_PROCESSES];
+
+ int keypress = 0;
+ int num_processes = 2;
+ int num_threads = 3;
+ int delay = 0;
+ int res = 0;
+ int pidx;
+ int pid;
+ int opt;
+
+ while ((opt = getopt(argc, argv, ":hkT:P:d:")) != -1) {
+ switch (opt) {
+ case 'P':
+ num_processes = (int)strtol(optarg, NULL, 10);
+ break;
+ case 'T':
+ num_threads = (int)strtoul(optarg, NULL, 10);
+ break;
+ case 'd':
+ delay = (int)strtol(optarg, NULL, 10);
+ break;
+ case 'k':
+ keypress = 1;
+ break;
+ case 'h':
+ printf(USAGE);
+ exit(EXIT_SUCCESS);
+ default:
+ handle_usage(20, "unknown option");
+ }
+ }
+
+ if (num_processes < 1 || num_processes > MAX_PROCESSES)
+ handle_usage(1, "Bad processes value");
+
+ if (num_threads < 1 || num_threads > MAX_THREADS)
+ handle_usage(2, "Bad thread value");
+
+ if (keypress)
+ delay = -1;
+
+ srand(time(NULL));
+
+ /* put into separate process group */
+ if (setpgid(0, 0) != 0)
+ handle_error("process group");
+
+ printf("\n## Create a thread/process/process group hiearchy\n");
+ create_processes(num_processes, num_threads, procs);
+ disp_processes(num_processes, procs);
+ validate(get_cs_cookie(0) == 0);
+
+ printf("\n## Set a cookie on entire process group\n");
+ if (_prctl(PR_SCHED_CORE, PR_SCHED_CORE_CREATE, 0, PIDTYPE_PGID, 0) < 0)
+ handle_error("core_sched create failed -- PGID");
+ disp_processes(num_processes, procs);
+
+ validate(get_cs_cookie(0) != 0);
+
+ /* get a random process pid */
+ pidx = rand() % num_processes;
+ pid = procs[pidx].cpid;
+
+ validate(get_cs_cookie(0) == get_cs_cookie(pid));
+ validate(get_cs_cookie(0) == get_cs_cookie(procs[pidx].thr_tids[0]));
+
+ printf("\n## Set a new cookie on entire process/TGID [%d]\n", pid);
+ if (_prctl(PR_SCHED_CORE, PR_SCHED_CORE_CREATE, pid, PIDTYPE_TGID, 0) < 0)
+ handle_error("core_sched create failed -- TGID");
+ disp_processes(num_processes, procs);
+
+ validate(get_cs_cookie(0) != get_cs_cookie(pid));
+ validate(get_cs_cookie(pid) != 0);
+ validate(get_cs_cookie(pid) == get_cs_cookie(procs[pidx].thr_tids[0]));
+
+ printf("\n## Copy the cookie of current/PGID[%d], to pid [%d] as PIDTYPE_PID\n",
+ getpid(), pid);
+ if (_prctl(PR_SCHED_CORE, PR_SCHED_CORE_SHARE_TO, pid, PIDTYPE_PID, 0) < 0)
+ handle_error("core_sched share to itself failed -- PID");
+ disp_processes(num_processes, procs);
+
+ validate(get_cs_cookie(0) == get_cs_cookie(pid));
+ validate(get_cs_cookie(pid) != 0);
+ validate(get_cs_cookie(pid) != get_cs_cookie(procs[pidx].thr_tids[0]));
+
+ printf("\n## Copy cookie from a thread [%d] to current/PGID [%d] as PIDTYPE_PID\n",
+ procs[pidx].thr_tids[0], getpid());
+ if (_prctl(PR_SCHED_CORE, PR_SCHED_CORE_SHARE_FROM, procs[pidx].thr_tids[0],
+ PIDTYPE_PID, 0) < 0)
+ handle_error("core_sched share from thread failed -- PID");
+ disp_processes(num_processes, procs);
+
+ validate(get_cs_cookie(0) == get_cs_cookie(procs[pidx].thr_tids[0]));
+ validate(get_cs_cookie(pid) != get_cs_cookie(procs[pidx].thr_tids[0]));
+
+ printf("\n## Copy cookie from current [%d] to current as pidtype PGID\n", getpid());
+ if (_prctl(PR_SCHED_CORE, PR_SCHED_CORE_SHARE_TO, 0, PIDTYPE_PGID, 0) < 0)
+ handle_error("core_sched share to self failed -- PGID");
+ disp_processes(num_processes, procs);
+
+ validate(get_cs_cookie(0) == get_cs_cookie(pid));
+ validate(get_cs_cookie(pid) != 0);
+ validate(get_cs_cookie(pid) == get_cs_cookie(procs[pidx].thr_tids[0]));
+
+ if (errors) {
+ printf("TESTS FAILED. errors: %d\n", errors);
+ res = 10;
+ } else {
+ printf("SUCCESS !!!\n");
+ }
+
+ if (keypress)
+ getchar();
+ else
+ sleep(delay);
+
+ for (pidx = 0; pidx < num_processes; ++pidx)
+ kill(procs[pidx].cpid, 15);
+
+ return res;
+}
projects / platform / kernel / linux-rpi.git / commitdiff