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<?xml version="1.0" encoding="UTF-8" standalone="yes"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>LKML: "tip-bot2 for Thomas Gleixner": [tip: timers/core] selftests/timers/posix-timers: Add a test for exact allocation mode</title><link href="/css/message.css" rel="stylesheet" type="text/css" /><link href="/css/wrap.css" rel="alternate stylesheet" type="text/css" title="wrap" /><link href="/css/nowrap.css" rel="stylesheet" type="text/css" title="nowrap" /><link href="/favicon.ico" rel="shortcut icon" /><script src="/js/simple-calendar.js" type="text/javascript"></script><script src="/js/styleswitcher.js" type="text/javascript"></script><link rel="alternate" type="application/rss+xml" title="lkml.org : last 100 messages" href="/rss.php" /><link rel="alternate" type="application/rss+xml" title="lkml.org : last messages by "tip-bot2 for Thomas Gleixner"" href="/groupie.php?aid=" /><script> var _paq = window._paq = window._paq || []; /* tracker methods like "setCustomDimension" should be called before "trackPageView" */ _paq.push(["setDoNotTrack", true]); _paq.push(["disableCookies"]); _paq.push(['trackPageView']); _paq.push(['enableLinkTracking']); (function() { var u="//m.lkml.org/"; _paq.push(['setTrackerUrl', u+'matomo.php']); _paq.push(['setSiteId', '1']); var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0]; g.async=true; g.src=u+'matomo.js'; s.parentNode.insertBefore(g,s); })(); </script></head><body onload="es.jasper.simpleCalendar.init();" itemscope="itemscope" itemtype="http://schema.org/BlogPosting"><table border="0" cellpadding="0" cellspacing="0"><tr><td width="180" align="center"><a href="/"><img style="border:0;width:135px;height:32px" src="/images/toprowlk.gif" alt="lkml.org" /></a></td><td width="32">聽</td><td class="nb"><div><a class="nb" href="/lkml"> [lkml]</a> 聽 <a class="nb" href="/lkml/2025"> [2025]</a> 聽 <a class="nb" href="/lkml/2025/3"> [Mar]</a> 聽 <a class="nb" href="/lkml/2025/3/13"> [13]</a> 聽 <a class="nb" href="/lkml/last100"> [last100]</a> 聽 <a href="/rss.php"><img src="/images/rss-or.gif" border="0" alt="RSS Feed" /></a></div><div>Views: <a href="#" class="nowrap" onclick="setActiveStyleSheet('wrap');return false;">[wrap]</a><a href="#" class="wrap" onclick="setActiveStyleSheet('nowrap');return false;">[no wrap]</a> 聽 <a class="nb" href="/lkml/mheaders/2025/3/13/617" onclick="this.href='/lkml/headers'+'/2025/3/13/617';">[headers]</a>聽 <a href="/lkml/bounce/2025/3/13/617">[forward]</a>聽 </div></td><td width="32">聽</td></tr><tr><td valign="top"><div class="es-jasper-simpleCalendar" baseurl="/lkml/"></div><div class="threadlist">Messages in this thread</div><ul class="threadlist"><li class="root"><a href="/lkml/2025/3/8/426">First message in thread</a></li><li><a href="/lkml/2025/3/8/445">Thomas Gleixner</a><ul><li><a href="/lkml/2025/3/10/254">Thomas Gleixner</a><ul><li><a href="/lkml/2025/3/11/1599">Frederic Weisbecker</a></li><li class="origin"><a href="">"tip-bot2 for Thomas Gleixner"</a></li></ul></li></ul></li></ul><div class="threadlist">Patch in this message</div><ul class="threadlist"><li><a href="/lkml/diff/2025/3/13/617/1">Get diff 1</a></li></ul></td><td width="32" rowspan="2" class="c" valign="top"><img src="/images/icornerl.gif" width="32" height="32" alt="/" /></td><td class="c" rowspan="2" valign="top" style="padding-top: 1em"><table><tr><td><table><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Thu, 13 Mar 2025 11:31:19 -0000</td></tr><tr><td class="lp">From</td><td class="rp" itemprop="author">"tip-bot2 for Thomas Gleixner" <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">[tip: timers/core] selftests/timers/posix-timers: Add a test for exact allocation mode</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">The following commit has been merged into the timers/core branch of tip: Commit-ID: 8e63360d869913265e5e4b623dcd23feff9fd000 Gitweb: <a href="https://git.kernel.org/tip/8e63360d869913265e5e4b623dcd23feff9fd000">https://git.kernel.org/tip/8e63360d869913265e5e4b623dcd23feff9fd000</a> Author: Thomas Gleixner <tglx@linutronix.de> AuthorDate: Mon, 10 Mar 2025 09:11:42 +01:00 Committer: Thomas Gleixner <tglx@linutronix.de> CommitterDate: Thu, 13 Mar 2025 12:07:18 +01:00 selftests/timers/posix-timers: Add a test for exact allocation mode The exact timer ID allocation mode is used by CRIU to restore timers with a given ID. Add a test case for it. It's skipped on older kernels when the prctl() fails. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Frederic Weisbecker <frederic@kernel.org> Link: <a href="https://lore.kernel.org/all/8734fl2tkx.ffs@tglx">https://lore.kernel.org/all/8734fl2tkx.ffs@tglx</a> --- tools/testing/selftests/timers/posix_timers.c | 73 +++++++++++++++++- 1 file changed, 72 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/timers/posix_timers.c b/tools/testing/selftests/timers/posix_timers.c index 9814b3a..f0eceb0 100644 --- a/tools/testing/selftests/timers/posix_timers.c +++ b/tools/testing/selftests/timers/posix_timers.c @@ -7,6 +7,7 @@ * Kernel loop code stolen from Steven Rostedt <srostedt@redhat.com> */ #define _GNU_SOURCE +#include <sys/prctl.h> #include <sys/time.h> #include <sys/types.h> #include <stdio.h> @@ -599,14 +600,84 @@ static void check_overrun(int which, const char *name) "check_overrun %s\n", name); } +#include <sys/syscall.h> + +static int do_timer_create(int *id) +{ + return syscall(__NR_timer_create, CLOCK_MONOTONIC, NULL, id); +} + +static int do_timer_delete(int id) +{ + return syscall(__NR_timer_delete, id); +} + +#ifndef PR_TIMER_CREATE_RESTORE_IDS +# define PR_TIMER_CREATE_RESTORE_IDS 77 +# define PR_TIMER_CREATE_RESTORE_IDS_OFF 0 +# define PR_TIMER_CREATE_RESTORE_IDS_ON 1 +# define PR_TIMER_CREATE_RESTORE_IDS_GET 2 +#endif + +static void check_timer_create_exact(void) +{ + int id; + + if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_ON, 0, 0, 0)) { + switch (errno) { + case EINVAL: + ksft_test_result_skip("check timer create exact, not supported\n"); + return; + default: + ksft_test_result_skip("check timer create exact, errno = %d\n", errno); + return; + } + } + + if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_GET, 0, 0, 0) != 1) + fatal_error(NULL, "prctl(GET) failed\n"); + + id = 8; + if (do_timer_create(&id) < 0) + fatal_error(NULL, "timer_create()"); + + if (do_timer_delete(id)) + fatal_error(NULL, "timer_delete()"); + + if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_OFF, 0, 0, 0)) + fatal_error(NULL, "prctl(OFF)"); + + if (prctl(PR_TIMER_CREATE_RESTORE_IDS, PR_TIMER_CREATE_RESTORE_IDS_GET, 0, 0, 0) != 0) + fatal_error(NULL, "prctl(GET) failed\n"); + + if (id != 8) { + ksft_test_result_fail("check timer create exact %d != 8\n", id); + return; + } + + /* Validate that it went back to normal mode and allocates ID 9 */ + if (do_timer_create(&id) < 0) + fatal_error(NULL, "timer_create()"); + + if (do_timer_delete(id)) + fatal_error(NULL, "timer_delete()"); + + if (id == 9) + ksft_test_result_pass("check timer create exact\n"); + else + ksft_test_result_fail("check timer create exact. Disabling failed.\n"); +} + int main(int argc, char **argv) { ksft_print_header(); - ksft_set_plan(18); + ksft_set_plan(19); ksft_print_msg("Testing posix timers. False negative may happen on CPU execution \n"); ksft_print_msg("based timers if other threads run on the CPU...\n"); + check_timer_create_exact(); + check_itimer(ITIMER_VIRTUAL, "ITIMER_VIRTUAL"); check_itimer(ITIMER_PROF, "ITIMER_PROF"); check_itimer(ITIMER_REAL, "ITIMER_REAL"); </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: 2025-03-13 12:32 聽聽 [W:0.477 / U:0.595 seconds] 漏2003-2020 <a href="http://blog.jasper.es/">Jasper Spaans</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>