diff options
Diffstat (limited to 'test/nptl/tst-cputimer3.c')
-rw-r--r-- | test/nptl/tst-cputimer3.c | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/test/nptl/tst-cputimer3.c b/test/nptl/tst-cputimer3.c new file mode 100644 index 000000000..056766a37 --- /dev/null +++ b/test/nptl/tst-cputimer3.c @@ -0,0 +1,130 @@ +/* Tests for POSIX timer implementation using another process's CPU clock. */ + +#include <unistd.h> + +#if _POSIX_THREADS && defined _POSIX_CPUTIME + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <fcntl.h> +#include <time.h> +#include <signal.h> +#include <sys/wait.h> + +static clockid_t child_clock; + +#define TEST_CLOCK child_clock +#define TEST_CLOCK_MISSING(clock) \ + (setup_test () ? "other-process CPU clock timer support" : NULL) + +/* This function is intended to rack up both user and system time. */ +static void +chew_cpu (void) +{ + while (1) + { + static volatile char buf[4096]; + for (int i = 0; i < 100; ++i) + for (size_t j = 0; j < sizeof buf; ++j) + buf[j] = 0xaa; + int nullfd = open ("/dev/null", O_WRONLY); + for (int i = 0; i < 100; ++i) + for (size_t j = 0; j < sizeof buf; ++j) + buf[j] = 0xbb; + write (nullfd, (char *) buf, sizeof buf); + close (nullfd); + if (getppid () == 1) + _exit (2); + } +} + +static pid_t child; +static void +cleanup_child (void) +{ + if (child <= 0) + return; + if (kill (child, SIGKILL) < 0 && errno != ESRCH) + printf ("cannot kill child %d: %m\n", child); + else + { + int status; + errno = 0; + if (waitpid (child, &status, 0) != child) + printf ("waitpid %d: %m\n", child); + } +} +#define CLEANUP_HANDLER cleanup_child () + +static int +setup_test (void) +{ + /* Test timers on a process CPU clock by having a child process eating + CPU. First make sure we can make such timers at all. */ + + int pipefd[2]; + if (pipe (pipefd) < 0) + { + printf ("pipe: %m\n"); + exit (1); + } + + child = fork (); + + if (child == 0) + { + char c; + close (pipefd[1]); + if (read (pipefd[0], &c, 1) == 1) + chew_cpu (); + _exit (1); + } + + if (child < 0) + { + printf ("fork: %m\n"); + exit (1); + } + + atexit (&cleanup_child); + + close (pipefd[0]); + + int e = clock_getcpuclockid (child, &child_clock); + if (e == EPERM) + { + puts ("clock_getcpuclockid does not support other processes"); + return 1; + } + if (e != 0) + { + printf ("clock_getcpuclockid: %s\n", strerror (e)); + exit (1); + } + + timer_t t; + if (timer_create (TEST_CLOCK, NULL, &t) != 0) + { + printf ("timer_create: %m\n"); + return 1; + } + timer_delete (t); + + /* Get the child started chewing. */ + if (write (pipefd[1], "x", 1) != 1) + { + printf ("write to pipe: %m\n"); + return 1; + } + close (pipefd[1]); + + return 0; +} + +#else +# define TEST_CLOCK_MISSING(clock) "process clocks" +#endif + +#include "tst-timer4.c" |