| Message ID | 20240919021709.511329-1-ming.lei@redhat.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | lib/sbitmap: define swap_lock as raw_spinlock_t | expand |
On 2024/9/19 10:17, Ming Lei wrote: > When called from sbitmap_queue_get(), sbitmap_deferred_clear() may be run > with preempt disabled. In RT kernel, spin_lock() can sleep, then warning > of "BUG: sleeping function called from invalid context" can be triggered. > > Fix it by replacing it with raw_spin_lock. > > Cc: Yang Yang <yang.yang@vivo.com> > Fixes: 72d04bdcf3f7 ("sbitmap: fix io hung due to race on sbitmap_word::cleared") > Signed-off-by: Ming Lei <ming.lei@redhat.com> > --- > include/linux/sbitmap.h | 2 +- > lib/sbitmap.c | 4 ++-- > 2 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h > index c09cdcc99471..189140bf11fc 100644 > --- a/include/linux/sbitmap.h > +++ b/include/linux/sbitmap.h > @@ -40,7 +40,7 @@ struct sbitmap_word { > /** > * @swap_lock: serializes simultaneous updates of ->word and ->cleared > */ > - spinlock_t swap_lock; > + raw_spinlock_t swap_lock; > } ____cacheline_aligned_in_smp; > > /** > diff --git a/lib/sbitmap.c b/lib/sbitmap.c > index 5e2e93307f0d..d3412984170c 100644 > --- a/lib/sbitmap.c > +++ b/lib/sbitmap.c > @@ -65,7 +65,7 @@ static inline bool sbitmap_deferred_clear(struct sbitmap_word *map, > { > unsigned long mask, word_mask; > > - guard(spinlock_irqsave)(&map->swap_lock); > + guard(raw_spinlock_irqsave)(&map->swap_lock); > > if (!map->cleared) { > if (depth == 0) > @@ -136,7 +136,7 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, > } > > for (i = 0; i < sb->map_nr; i++) > - spin_lock_init(&sb->map[i].swap_lock); > + raw_spin_lock_init(&sb->map[i].swap_lock); > > return 0; > } Looks good. Feel free to add: Reviewed-by: Yang Yang <yang.yang@vivo.com> Thanks.
diff --git a/include/linux/sbitmap.h b/include/linux/sbitmap.h index c09cdcc99471..189140bf11fc 100644 --- a/include/linux/sbitmap.h +++ b/include/linux/sbitmap.h @@ -40,7 +40,7 @@ struct sbitmap_word { /** * @swap_lock: serializes simultaneous updates of ->word and ->cleared */ - spinlock_t swap_lock; + raw_spinlock_t swap_lock; } ____cacheline_aligned_in_smp; /** diff --git a/lib/sbitmap.c b/lib/sbitmap.c index 5e2e93307f0d..d3412984170c 100644 --- a/lib/sbitmap.c +++ b/lib/sbitmap.c @@ -65,7 +65,7 @@ static inline bool sbitmap_deferred_clear(struct sbitmap_word *map, { unsigned long mask, word_mask; - guard(spinlock_irqsave)(&map->swap_lock); + guard(raw_spinlock_irqsave)(&map->swap_lock); if (!map->cleared) { if (depth == 0) @@ -136,7 +136,7 @@ int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift, } for (i = 0; i < sb->map_nr; i++) - spin_lock_init(&sb->map[i].swap_lock); + raw_spin_lock_init(&sb->map[i].swap_lock); return 0; }
When called from sbitmap_queue_get(), sbitmap_deferred_clear() may be run with preempt disabled. In RT kernel, spin_lock() can sleep, then warning of "BUG: sleeping function called from invalid context" can be triggered. Fix it by replacing it with raw_spin_lock. Cc: Yang Yang <yang.yang@vivo.com> Fixes: 72d04bdcf3f7 ("sbitmap: fix io hung due to race on sbitmap_word::cleared") Signed-off-by: Ming Lei <ming.lei@redhat.com> --- include/linux/sbitmap.h | 2 +- lib/sbitmap.c | 4 ++-- 2 files changed, 3 insertions(+), 3 deletions(-)