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Add a test case for it.<br /><br />It's skipped on older kernels when the prctl() fails.<br /><br />Signed-off-by: Thomas Gleixner <tglx@linutronix.de><br /><br />---<br />V3: Use the PRCTL defines<br />V2: Adopt to the ID counter change in the exact mode case<br />---<br /> tools/testing/selftests/timers/posix_timers.c | 66 +++++++++++++++++++++++++-<br /> 1 file changed, 65 insertions(+), 1 deletion(-)<br /><br />--- a/tools/testing/selftests/timers/posix_timers.c<br />+++ b/tools/testing/selftests/timers/posix_timers.c<br />@@ -7,6 +7,7 @@<br /> * Kernel loop code stolen from Steven Rostedt <srostedt@redhat.com><br /> */<br /> #define _GNU_SOURCE<br />+#include <sys/prctl.h><br /> #include <sys/time.h><br /> #include <sys/types.h><br /> #include <stdio.h><br />@@ -599,14 +600,77 @@ static void check_overrun(int which, con<br /> "check_overrun %s\n", name);<br /> }<br /> <br />+#include <sys/syscall.h><br />+<br />+static int do_timer_create(int *id)<br />+{<br />+ return syscall(__NR_timer_create, CLOCK_MONOTONIC, NULL, id);<br />+}<br />+<br />+static int do_timer_delete(int id)<br />+{<br />+ return syscall(__NR_timer_delete, id);<br />+}<br />+<br />+#ifndef define PR_TIMER_CREATE_RESTORE_IDS<br />+# define PR_TIMER_CREATE_RESTORE_IDS 77<br />+# define PR_TIMER_CREATE_RESTORE_IDS_OFF 0<br />+# define PR_TIMER_CREATE_RESTORE_IDS_ON 1<br />+#endif<br />+<br />+static void check_timer_create_exact(void)<br />+{<br />+ int id;<br />+<br />+ if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_ON, 0, 0, 0)) {<br />+ switch (errno) {<br />+ case EINVAL:<br />+ ksft_test_result_skip("check timer create exact, not supported\n");<br />+ return;<br />+ default:<br />+ ksft_test_result_skip("check timer create exact, errno = %d\n", errno);<br />+ return;<br />+ }<br />+ }<br />+<br />+ id = 8;<br />+ if (do_timer_create(&id) < 0)<br />+ fatal_error(NULL, "timer_create()");<br />+<br />+ if (do_timer_delete(id))<br />+ fatal_error(NULL, "timer_delete()");<br />+<br />+ if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_OFF, 0, 0, 0))<br />+ fatal_error(NULL, "prctl()");<br />+<br />+ if (id != 8) {<br />+ ksft_test_result_fail("check timer create exact %d != 8\n", id);<br />+ return;<br />+ }<br />+<br />+ /* Validate that it went back to normal mode and allocates ID 9 */<br />+ if (do_timer_create(&id) < 0)<br />+ fatal_error(NULL, "timer_create()");<br />+<br />+ if (do_timer_delete(id))<br />+ fatal_error(NULL, "timer_delete()");<br />+<br />+ if (id == 9)<br />+ ksft_test_result_pass("check timer create exact\n");<br />+ else<br />+ ksft_test_result_fail("check timer create exact. Disabling failed.\n");<br />+}<br />+<br /> int main(int argc, char **argv)<br /> {<br /> ksft_print_header();<br />- ksft_set_plan(18);<br />+ ksft_set_plan(19);<br /> <br /> ksft_print_msg("Testing posix timers. False negative may happen on CPU execution \n");<br /> ksft_print_msg("based timers if other threads run on the CPU...\n");<br /> <br />+ check_timer_create_exact();<br />+<br /> check_itimer(ITIMER_VIRTUAL, "ITIMER_VIRTUAL");<br /> check_itimer(ITIMER_PROF, "ITIMER_PROF");<br /> check_itimer(ITIMER_REAL, "ITIMER_REAL");<br /><br /></pre></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerr.gif" width="32" height="32" alt="\" /></td></tr><tr><td align="right" valign="bottom"> 聽 </td></tr><tr><td align="right" valign="bottom">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerl.gif" width="32" height="32" alt="\" /></td><td class="c">聽</td><td class="c" valign="bottom" style="padding-bottom: 0px"><img src="/images/bcornerr.gif" width="32" height="32" alt="/" /></td></tr><tr><td align="right" valign="top" colspan="2"> 聽 </td><td class="lm">Last update: 2025-03-08 17:52 聽聽 [W:0.641 / U:1.366 seconds]<br />漏2003-2020 <a href="http://blog.jasper.es/"><span itemprop="editor">Jasper Spaans</span></a>|hosted at <a href="https://www.digitalocean.com/?refcode=9a8e99d24cf9">Digital Ocean</a> and my Meterkast|<a href="http://blog.jasper.es/categories.html#lkml-ref">Read the blog</a></td><td>聽</td></tr></table><script language="javascript" src="/js/styleswitcher.js" type="text/javascript"></script></body></html>