The only tests I could come up with for /proc/uptime are: * test that values increase monotonically for 1 second, * bounce around CPUs and test the same thing.
Avoid glibc like plague for affinity given patches like this: https://marc.info/?l=linux-kernel&m=152130031912594&w=4 Signed-off-by: Alexey Dobriyan <adobri...@gmail.com> --- tools/testing/selftests/proc/.gitignore | 2 tools/testing/selftests/proc/Makefile | 2 tools/testing/selftests/proc/proc-uptime-001.c | 45 ++++++++++++++ tools/testing/selftests/proc/proc-uptime-002.c | 79 +++++++++++++++++++++++++ tools/testing/selftests/proc/proc-uptime.h | 74 +++++++++++++++++++++++ 5 files changed, 202 insertions(+) --- a/tools/testing/selftests/proc/.gitignore +++ b/tools/testing/selftests/proc/.gitignore @@ -4,4 +4,6 @@ /proc-self-map-files-002 /proc-self-syscall /proc-self-wchan +/proc-uptime-001 +/proc-uptime-002 /read --- a/tools/testing/selftests/proc/Makefile +++ b/tools/testing/selftests/proc/Makefile @@ -7,6 +7,8 @@ TEST_GEN_PROGS += proc-self-map-files-001 TEST_GEN_PROGS += proc-self-map-files-002 TEST_GEN_PROGS += proc-self-syscall TEST_GEN_PROGS += proc-self-wchan +TEST_GEN_PROGS += proc-uptime-001 +TEST_GEN_PROGS += proc-uptime-002 TEST_GEN_PROGS += read include ../lib.mk new file mode 100644 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime-001.c @@ -0,0 +1,45 @@ +/* + * Copyright © 2018 Alexey Dobriyan <adobri...@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +// Test that values in /proc/uptime increment monotonically. +#undef NDEBUG +#include <assert.h> +#include <stdint.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "proc-uptime.h" + +int main(void) +{ + uint64_t start, u0, u1, i0, i1; + int fd; + + fd = open("/proc/uptime", O_RDONLY); + assert(fd >= 0); + + proc_uptime(fd, &u0, &i0); + start = u0; + do { + proc_uptime(fd, &u1, &i1); + assert(u1 >= u0); + assert(i1 >= i0); + u0 = u1; + i0 = i1; + } while (u1 - start < 100); + + return 0; +} new file mode 100644 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime-002.c @@ -0,0 +1,79 @@ +/* + * Copyright © 2018 Alexey Dobriyan <adobri...@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +// Test that values in /proc/uptime increment monotonically +// while shifting across CPUs. +#define _GNU_SOURCE +#undef NDEBUG +#include <assert.h> +#include <unistd.h> +#include <sys/syscall.h> +#include <stdlib.h> +#include <string.h> + +#include <stdint.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +#include "proc-uptime.h" + +static inline int sys_sched_getaffinity(pid_t pid, unsigned int len, unsigned long *m) +{ + return syscall(SYS_sched_getaffinity, pid, len, m); +} + +static inline int sys_sched_setaffinity(pid_t pid, unsigned int len, unsigned long *m) +{ + return syscall(SYS_sched_setaffinity, pid, len, m); +} + +int main(void) +{ + unsigned int len; + unsigned long *m; + unsigned int cpu; + uint64_t u0, u1, i0, i1; + int fd; + + /* find out "nr_cpu_ids" */ + m = NULL; + len = 0; + do { + len += sizeof(unsigned long); + free(m); + m = malloc(len); + } while (sys_sched_getaffinity(0, len, m) == -EINVAL); + + fd = open("/proc/uptime", O_RDONLY); + assert(fd >= 0); + + proc_uptime(fd, &u0, &i0); + for (cpu = 0; cpu < len * 8; cpu++) { + memset(m, 0, len); + m[cpu / (8 * sizeof(unsigned long))] |= 1UL << (cpu % (8 * sizeof(unsigned long))); + + /* CPU might not exist, ignore error */ + sys_sched_setaffinity(0, len, m); + + proc_uptime(fd, &u1, &i1); + assert(u1 >= u0); + assert(i1 >= i0); + u0 = u1; + i0 = i1; + } + + return 0; +} new file mode 100644 --- /dev/null +++ b/tools/testing/selftests/proc/proc-uptime.h @@ -0,0 +1,74 @@ +/* + * Copyright © 2018 Alexey Dobriyan <adobri...@gmail.com> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ +#undef NDEBUG +#include <assert.h> +#include <errno.h> +#include <string.h> +#include <stdlib.h> +#include <unistd.h> + +static unsigned long long xstrtoull(const char *p, char **end) +{ + if (*p == '0') { + *end = (char *)p + 1; + return 0; + } else if ('1' <= *p && *p <= '9') { + unsigned long long val; + + errno = 0; + val = strtoull(p, end, 10); + assert(errno == 0); + return val; + } else + assert(0); +} + +static void proc_uptime(int fd, uint64_t *uptime, uint64_t *idle) +{ + uint64_t val1, val2; + char buf[64], *p; + ssize_t rv; + + /* save "p < end" checks */ + memset(buf, 0, sizeof(buf)); + rv = pread(fd, buf, sizeof(buf), 0); + assert(0 <= rv && rv <= sizeof(buf)); + buf[sizeof(buf) - 1] = '\0'; + + p = buf; + + val1 = xstrtoull(p, &p); + assert(p[0] == '.'); + assert('0' <= p[1] && p[1] <= '9'); + assert('0' <= p[2] && p[2] <= '9'); + assert(p[3] == ' '); + + val2 = (p[1] - '0') * 10 + p[2] - '0'; + *uptime = val1 * 100 + val2; + + p += 4; + + val1 = xstrtoull(p, &p); + assert(p[0] == '.'); + assert('0' <= p[1] && p[1] <= '9'); + assert('0' <= p[2] && p[2] <= '9'); + assert(p[3] == '\n'); + + val2 = (p[1] - '0') * 10 + p[2] - '0'; + *idle = val1 * 100 + val2; + + assert(p + 4 == buf + rv); +}
