diff options
Diffstat (limited to 'tools/testing/selftests/powerpc/pmu/lib.c')
| -rw-r--r-- | tools/testing/selftests/powerpc/pmu/lib.c | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/pmu/lib.c b/tools/testing/selftests/powerpc/pmu/lib.c new file mode 100644 index 000000000..88690b97b --- /dev/null +++ b/tools/testing/selftests/powerpc/pmu/lib.c @@ -0,0 +1,227 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2014, Michael Ellerman, IBM Corp. + */ + +#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 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) +{ + long current; + char *end, buf[16]; + FILE *f; + bool rc; + + rc = false; + + 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 = strtol(buf, &end, 10); + + if (end == buf) { + printf("Couldn't parse " PARANOID_PATH "?\n"); + goto out_close; + } + + if (current >= level) + goto out_close; + + rc = true; +out_close: + fclose(f); +out: + return rc; +} + |