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-rw-r--r--kernel/tools/testing/selftests/powerpc/pmu/lib.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/kernel/tools/testing/selftests/powerpc/pmu/lib.c b/kernel/tools/testing/selftests/powerpc/pmu/lib.c
new file mode 100644
index 000000000..a07104c2a
--- /dev/null
+++ b/kernel/tools/testing/selftests/powerpc/pmu/lib.c
@@ -0,0 +1,253 @@
+/*
+ * Copyright 2014, Michael Ellerman, IBM Corp.
+ * Licensed under GPLv2.
+ */
+
+#define _GNU_SOURCE /* For CPU_ZERO etc. */
+
+#include <errno.h>
+#include <sched.h>
+#include <setjmp.h>
+#include <stdlib.h>
+#include <sys/wait.h>
+
+#include "utils.h"
+#include "lib.h"
+
+
+int pick_online_cpu(void)
+{
+ cpu_set_t mask;
+ int cpu;
+
+ CPU_ZERO(&mask);
+
+ if (sched_getaffinity(0, sizeof(mask), &mask)) {
+ perror("sched_getaffinity");
+ return -1;
+ }
+
+ /* We prefer a primary thread, but skip 0 */
+ for (cpu = 8; cpu < CPU_SETSIZE; cpu += 8)
+ if (CPU_ISSET(cpu, &mask))
+ return cpu;
+
+ /* Search for anything, but in reverse */
+ for (cpu = CPU_SETSIZE - 1; cpu >= 0; cpu--)
+ if (CPU_ISSET(cpu, &mask))
+ return cpu;
+
+ printf("No cpus in affinity mask?!\n");
+ return -1;
+}
+
+int bind_to_cpu(int cpu)
+{
+ cpu_set_t mask;
+
+ printf("Binding to cpu %d\n", cpu);
+
+ CPU_ZERO(&mask);
+ CPU_SET(cpu, &mask);
+
+ return sched_setaffinity(0, sizeof(mask), &mask);
+}
+
+#define PARENT_TOKEN 0xAA
+#define CHILD_TOKEN 0x55
+
+int sync_with_child(union pipe read_pipe, union pipe write_pipe)
+{
+ char c = PARENT_TOKEN;
+
+ FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
+ FAIL_IF(read(read_pipe.read_fd, &c, 1) != 1);
+ if (c != CHILD_TOKEN) /* sometimes expected */
+ return 1;
+
+ return 0;
+}
+
+int wait_for_parent(union pipe read_pipe)
+{
+ char c;
+
+ FAIL_IF(read(read_pipe.read_fd, &c, 1) != 1);
+ FAIL_IF(c != PARENT_TOKEN);
+
+ return 0;
+}
+
+int notify_parent(union pipe write_pipe)
+{
+ char c = CHILD_TOKEN;
+
+ FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
+
+ return 0;
+}
+
+int notify_parent_of_error(union pipe write_pipe)
+{
+ char c = ~CHILD_TOKEN;
+
+ FAIL_IF(write(write_pipe.write_fd, &c, 1) != 1);
+
+ return 0;
+}
+
+int wait_for_child(pid_t child_pid)
+{
+ int rc;
+
+ if (waitpid(child_pid, &rc, 0) == -1) {
+ perror("waitpid");
+ return 1;
+ }
+
+ if (WIFEXITED(rc))
+ rc = WEXITSTATUS(rc);
+ else
+ rc = 1; /* Signal or other */
+
+ return rc;
+}
+
+int kill_child_and_wait(pid_t child_pid)
+{
+ kill(child_pid, SIGTERM);
+
+ return wait_for_child(child_pid);
+}
+
+static int eat_cpu_child(union pipe read_pipe, union pipe write_pipe)
+{
+ volatile int i = 0;
+
+ /*
+ * We are just here to eat cpu and die. So make sure we can be killed,
+ * and also don't do any custom SIGTERM handling.
+ */
+ signal(SIGTERM, SIG_DFL);
+
+ notify_parent(write_pipe);
+ wait_for_parent(read_pipe);
+
+ /* Soak up cpu forever */
+ while (1) i++;
+
+ return 0;
+}
+
+pid_t eat_cpu(int (test_function)(void))
+{
+ union pipe read_pipe, write_pipe;
+ int cpu, rc;
+ pid_t pid;
+
+ cpu = pick_online_cpu();
+ FAIL_IF(cpu < 0);
+ FAIL_IF(bind_to_cpu(cpu));
+
+ if (pipe(read_pipe.fds) == -1)
+ return -1;
+
+ if (pipe(write_pipe.fds) == -1)
+ return -1;
+
+ pid = fork();
+ if (pid == 0)
+ exit(eat_cpu_child(write_pipe, read_pipe));
+
+ if (sync_with_child(read_pipe, write_pipe)) {
+ rc = -1;
+ goto out;
+ }
+
+ printf("main test running as pid %d\n", getpid());
+
+ rc = test_function();
+out:
+ kill(pid, SIGKILL);
+
+ return rc;
+}
+
+struct addr_range libc, vdso;
+
+int parse_proc_maps(void)
+{
+ unsigned long start, end;
+ char execute, name[128];
+ FILE *f;
+ int rc;
+
+ f = fopen("/proc/self/maps", "r");
+ if (!f) {
+ perror("fopen");
+ return -1;
+ }
+
+ do {
+ /* This skips line with no executable which is what we want */
+ rc = fscanf(f, "%lx-%lx %*c%*c%c%*c %*x %*d:%*d %*d %127s\n",
+ &start, &end, &execute, name);
+ if (rc <= 0)
+ break;
+
+ if (execute != 'x')
+ continue;
+
+ if (strstr(name, "libc")) {
+ libc.first = start;
+ libc.last = end - 1;
+ } else if (strstr(name, "[vdso]")) {
+ vdso.first = start;
+ vdso.last = end - 1;
+ }
+ } while(1);
+
+ fclose(f);
+
+ return 0;
+}
+
+#define PARANOID_PATH "/proc/sys/kernel/perf_event_paranoid"
+
+bool require_paranoia_below(int level)
+{
+ unsigned long current;
+ char *end, buf[16];
+ FILE *f;
+ int rc;
+
+ rc = -1;
+
+ f = fopen(PARANOID_PATH, "r");
+ if (!f) {
+ perror("fopen");
+ goto out;
+ }
+
+ if (!fgets(buf, sizeof(buf), f)) {
+ printf("Couldn't read " PARANOID_PATH "?\n");
+ goto out_close;
+ }
+
+ current = strtoul(buf, &end, 10);
+
+ if (end == buf) {
+ printf("Couldn't parse " PARANOID_PATH "?\n");
+ goto out_close;
+ }
+
+ if (current >= level)
+ goto out;
+
+ rc = 0;
+out_close:
+ fclose(f);
+out:
+ return rc;
+}
+