ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 12:43:29 +02:00
Code Issues Packages Projects Releases Wiki Activity

atomic: Add irqsave variant of atomic_dec_and_lock()

Browse Source 
There are in-tree users of atomic_dec_and_lock() which must acquire the
spin lock with interrupts disabled. To workaround the lack of an irqsave
variant of atomic_dec_and_lock() they use local_irq_save() at the call
site. This causes extra code and creates in some places unneeded long
interrupt disabled times. These places need also extra treatment for
PREEMPT_RT due to the disconnect of the irq disabling and the lock
function.

Implement the missing irqsave variant of the function.

Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r20180612161621.22645-3-bigeasy@linutronix.de
This commit is contained in:
Anna-Maria Gleixner
2018-06-12 18:16:20 +02:00
committed by Thomas Gleixner
parent f2ae679411
commit ccfbb5bed4
2 changed files with 21 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
include/linux/spinlock.h
View File

@@ -427,6 +427,11 @@ extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock);
#define atomic_dec_and_lock(atomic, lock) \
__cond_lock(lock, _atomic_dec_and_lock(atomic, lock))
extern int _atomic_dec_and_lock_irqsave(atomic_t *atomic, spinlock_t *lock,
unsigned long *flags);
#define atomic_dec_and_lock_irqsave(atomic, lock, flags) \
__cond_lock(lock, _atomic_dec_and_lock_irqsave(atomic, lock, &(flags)))
int alloc_bucket_spinlocks(spinlock_t **locks, unsigned int *lock_mask,
size_t max_size, unsigned int cpu_mult,
gfp_t gfp);