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lib/flex_proportions.c: remove local_irq_ops in fprop_new_period() 

commit e78d4833c03e28> "lib: Fix possible deadlock in flexible proportion
code" adds the local_irq_ops because percpu_counter_{sum |add} ops'lock
can cause deadlock by interrupts.  Now percpu_counter _{sum|add} ops use
raw_spin_(un)lock_irq*, so revert the commit and resolve the conflict.

Link: https://lkml.kernel.org/r/20220604131502.5190-1-wuchi.zero@gmail.com
Signed-off-by: wuchi <wuchi.zero@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
wuchi 2022-06-04 21:15:02 +08:00 committed by akpm
parent 0cc011c576
commit a91befde35
1 changed files with 2 additions and 8 deletions
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10
lib/flex_proportions.c
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@ -63,18 +63,13 @@ void fprop_global_destroy(struct fprop_global *p)
*/
bool fprop_new_period(struct fprop_global *p, int periods)
{
s64 events;
unsigned long flags;
s64 events = percpu_counter_sum(&p->events);
local_irq_save(flags);
events = percpu_counter_sum(&p->events);
/*
* Don't do anything if there are no events.
*/
if (events <= 1) {
local_irq_restore(flags);
if (events <= 1)
return false;
}
write_seqcount_begin(&p->sequence);
if (periods < 64)
events -= events >> periods;
@ -82,7 +77,6 @@ bool fprop_new_period(struct fprop_global *p, int periods)
percpu_counter_add(&p->events, -events);
p->period += periods;
write_seqcount_end(&p->sequence);
local_irq_restore(flags);
return true;
}