#include #include #include #include struct once_work { struct work_struct work; struct static_key *key; }; static void once_deferred(struct work_struct *w) { struct once_work *work; work = container_of(w, struct once_work, work); BUG_ON(!static_key_enabled(work->key)); static_key_slow_dec(work->key); kfree(work); } static void once_disable_jump(struct static_key *key) { struct once_work *w; w = kmalloc(sizeof(*w), GFP_ATOMIC); if (!w) return; INIT_WORK(&w->work, once_deferred); w->key = key; schedule_work(&w->work); } static DEFINE_SPINLOCK(once_lock); bool __do_once_start(bool *done, unsigned long *flags) __acquires(once_lock) { spin_lock_irqsave(&once_lock, *flags); if (*done) { spin_unlock_irqrestore(&once_lock, *flags); /* Keep sparse happy by restoring an even lock count on * this lock. In case we return here, we don't call into * __do_once_done but return early in the DO_ONCE() macro. */ __acquire(once_lock); return false; } return true; } EXPORT_SYMBOL(__do_once_start); void __do_once_done(bool *done, struct static_key *once_key, unsigned long *flags) __releases(once_lock) { *done = true; spin_unlock_irqrestore(&once_lock, *flags); once_disable_jump(once_key); } EXPORT_SYMBOL(__do_once_done); p-back'>packet-rx-pump-back net-next plumbingsTobias Klauser
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorThomas Gleixner <tglx@linutronix.de>2017-01-31 09:37:34 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100
commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch)
treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /sound/soc/codecs/tas5720.c
parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'sound/soc/codecs/tas5720.c')