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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /tools/testing/selftests/proc/proc-uptime-002.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/proc/proc-uptime-002.c')
-rw-r--r--tools/testing/selftests/proc/proc-uptime-002.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/tools/testing/selftests/proc/proc-uptime-002.c b/tools/testing/selftests/proc/proc-uptime-002.c
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+++ b/tools/testing/selftests/proc/proc-uptime-002.c
@@ -0,0 +1,92 @@
+/*
+ * Copyright © 2018 Alexey Dobriyan <adobriyan@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 boottime value in /proc/uptime and CLOCK_BOOTTIME increment
+// monotonically while shifting across CPUs. We don't test idle time
+// monotonicity due to broken iowait task counting, cf: comment above
+// get_cpu_idle_time_us()
+#undef NDEBUG
+#include <assert.h>
+#include <errno.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)
+{
+ uint64_t u0, u1, c0, c1;
+ unsigned int len;
+ unsigned long *m;
+ unsigned int cpu;
+ 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) == -1 && errno == EINVAL);
+
+ fd = open("/proc/uptime", O_RDONLY);
+ assert(fd >= 0);
+
+ u0 = proc_uptime(fd);
+ c0 = clock_boottime();
+
+ 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);
+
+ u1 = proc_uptime(fd);
+ c1 = clock_boottime();
+
+ /* Is /proc/uptime monotonic ? */
+ assert(u1 >= u0);
+
+ /* Is CLOCK_BOOTTIME monotonic ? */
+ assert(c1 >= c0);
+
+ /* Is CLOCK_BOOTTIME VS /proc/uptime monotonic ? */
+ assert(c0 >= u0);
+
+ u0 = u1;
+ c0 = c1;
+ }
+
+ return 0;
+}