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Thomas Gleixner"</a></li></ul></li></ul></li></ul></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">From</td><td class="rp" itemprop="author">Thomas Gleixner <></td></tr><tr><td class="lp">Subject</td><td class="rp" itemprop="name">[patch V3 00/18] posix-timers: Rework the global hash table and provide a sane mechanism for CRIU</td></tr><tr><td class="lp">Date</td><td class="rp" itemprop="datePublished">Sat, 8 Mar 2025 17:48:08 +0100 (CET)</td></tr></table></td><td></td></tr></table><pre itemprop="articleBody">This is a follow up on V2 of this work, which can be found here:<br /><br /> <a href="https://lore.kernel.org/all/20250224095736.145530367@linutronix.de">https://lore.kernel.org/all/20250224095736.145530367@linutronix.de</a><br /><br />It addresses the scalability problem of the posix timer hash and provides a<br />performant mechanism to restore Posix timers with a given ID along with a<br />couple of preperatory cleanups and enhancements. More details about<br />implementation choices are in the change logs and the cover letter of V1:<br /><br /> <a href="https://lore.kernel.org/all/20250302185753.311903554@linutronix.de">https://lore.kernel.org/all/20250302185753.311903554@linutronix.de</a><br /><br />Changes vs. V2:<br /><br /> - Ensure consistency on timer_create() (new patch) - Frederic<br /> - Pick up the lock_timer() conditional unlock fix (was V2a)<br /> - Use proper defines in selftests<br /> - Pick up review/ack tags<br /><br />The series survives all posix timer tests and did not show any regressions<br />so far.<br /><br />The series is based on:<br /><br /> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip timers/core<br /><br />and is also available from git:<br /><br /> git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git timers/posix<br /><br />Thanks,<br /><br /> tglx<br />---<br />Eric Dumazet (3):<br /> posix-timers: Initialise timer before adding it to the hash table<br /> posix-timers: Add cond_resched() to posix_timer_add() search loop<br /> posix-timers: Make signal_struct:: Next_posix_timer_id an atomic_t<br /><br />Peter Zijlstra (1):<br /> posix-timers: Make lock_timer() use guard()<br /><br />Thomas Gleixner (14):<br /> posix-timers: Ensure that timer initialization is fully visible<br /> posix-timers: Cleanup includes<br /> posix-timers: Remove a few paranoid warnings<br /> posix-timers: Remove SLAB_PANIC from kmem cache<br /> posix-timers: Use guards in a few places<br /> posix-timers: Simplify lock/unlock_timer()<br /> posix-timers: Rework timer removal<br /> posix-timers: Improve hash table performance<br /> posix-timers: Switch to jhash32()<br /> posix-timers: Avoid false cacheline sharing<br /> posix-timers: Make per process list RCU safe<br /> posix-timers: Dont iterate /proc/$PID/timers with sighand:: Siglock held<br /> posix-timers: Provide a mechanism to allocate a given timer ID<br /> selftests/timers/posix-timers: Add a test for exact allocation mode<br /><br /><br /> fs/proc/base.c | 48 --<br /> include/linux/cleanup.h | 22 -<br /> include/linux/posix-timers.h | 30 +<br /> include/linux/sched/signal.h | 3 <br /> include/uapi/linux/prctl.h | 10 <br /> kernel/signal.c | 2 <br /> kernel/sys.c | 5 <br /> kernel/time/posix-timers.c | 540 +++++++++++++-------------<br /> tools/testing/selftests/timers/posix_timers.c | 66 +++<br /> 9 files changed, 418 insertions(+), 308 deletions(-)<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 17:49 聽聽 [W:1.231 / U:2.238 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>