From: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx> Subject: bdi: use irqsave variant of refcount_dec_and_lock() The irqsave variant of refcount_dec_and_lock handles irqsave/restore when taking/releasing the spin lock. With this variant the call of local_irq_save/restore is no longer required. [bigeasy@xxxxxxxxxxxxx: s@atomic_dec_and_lock@refcount_dec_and_lock@g] Link: http://lkml.kernel.org/r/20180703200141.28415-5-bigeasy@xxxxxxxxxxxxx Signed-off-by: Anna-Maria Gleixner <anna-maria@xxxxxxxxxxxxx> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx> Acked-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/backing-dev.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) --- a/mm/backing-dev.c~bdi-use-irqsave-variant-of-refcount_dec_and_lock +++ a/mm/backing-dev.c @@ -508,11 +508,8 @@ void wb_congested_put(struct bdi_writeba { unsigned long flags; - local_irq_save(flags); - if (!refcount_dec_and_lock(&congested->refcnt, &cgwb_lock)) { - local_irq_restore(flags); + if (!refcount_dec_and_lock_irqsave(&congested->refcnt, &cgwb_lock, &flags)) return; - } /* bdi might already have been destroyed leaving @congested unlinked */ if (congested->__bdi) { _
