[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-ID: <20250302185753.311903554@linutronix.de>
Date: Sun, 2 Mar 2025 20:36:42 +0100 (CET)
From: Thomas Gleixner <tglx@...utronix.de>
To: LKML <linux-kernel@...r.kernel.org>
Cc: Anna-Maria Behnsen <anna-maria@...utronix.de>,
Frederic Weisbecker <frederic@...nel.org>,
Benjamin Segall <bsegall@...gle.com>,
Eric Dumazet <edumazet@...gle.com>,
Andrey Vagin <avagin@...nvz.org>,
Pavel Tikhomirov <ptikhomirov@...tuozzo.com>,
Peter Zijlstra <peterz@...radead.org>
Subject: [patch V2 00/17] posix-timers: Rework the global hash table and
provide a sane mechanism for CRIU
This is a follow up on V1 of this work, which can be found here:
https://lore.kernel.org/all/20250224095736.145530367@linutronix.de
It addresses the scalability problem of the posix timer hash and provides a
performant mechanism to restore Posix timers with a given ID along with a
couple of preperatory cleanups and enhancements. More details about
implementation choices are in the change logs and the cover letter of V1.
Changes vs. V1:
- Simplify the timer removal cleanup - PeterZ
- Use guards consistently - PeterZ
- Switch to jhash32()
- Avoid false sharing by reordering struct k_itimer
- Advance the ID counter when restoring
- A few additional cleanups
The series survives all posix timer tests and did not show any regressions
so far.
The series is based on:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip timers/core
and is also available from git:
git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git timers/posix
Thanks,
tglx
---
Eric Dumazet (3):
posix-timers: Initialise timer before adding it to the hash table
posix-timers: Add cond_resched() to posix_timer_add() search loop
posix-timers: Make signal_struct::next_posix_timer_id an atomic_t
Peter Zijlstra (1):
posix-timers: Make lock_timer() use guard()
Thomas Gleixner (13):
posix-timers: Cleanup includes
posix-timers: Remove a few paranoid warnings
posix-timers: Remove SLAB_PANIC from kmem cache
posix-timers: Use guards in a few places
posix-timers: Simplify lock/unlock_timer()
posix-timers: Rework timer removal
posix-timers: Improve hash table performance
posix-timers: Switch to jhash32()
posix-timers: Avoid false cacheline sharing
posix-timers: Make per process list RCU safe
posix-timers: Don't iterate /proc/$PID/timers with sighand::siglock held
posix-timers: Provide a mechanism to allocate a given timer ID
selftests/timers/posix-timers: Add a test for exact allocation mode
fs/proc/base.c | 48 --
include/linux/cleanup.h | 22 -
include/linux/posix-timers.h | 30 +
include/linux/sched/signal.h | 3
include/uapi/linux/prctl.h | 10
kernel/signal.c | 2
kernel/sys.c | 5
kernel/time/posix-timers.c | 530 +++++++++++++-------------
tools/testing/selftests/timers/posix_timers.c | 60 ++
9 files changed, 403 insertions(+), 307 deletions(-)
Powered by blists - more mailing lists