On 10/2/19 1:14 PM, Mikulas Patocka wrote: > This is simple refactoring that moves code for modifying the semaphore > cow_count into separate functions. It is needed by the following patch. > > Signed-off-by: Mikulas Patocka <[email protected]> > Cc: [email protected] # v5.0+ > Fixes: 721b1d98fb51 ("dm snapshot: Fix excessive memory usage and workqueue > stalls") >
Reviewed-by: Nikos Tsironis <[email protected]> > --- > drivers/md/dm-snap.c | 20 +++++++++++++++----- > 1 file changed, 15 insertions(+), 5 deletions(-) > > Index: linux-2.6/drivers/md/dm-snap.c > =================================================================== > --- linux-2.6.orig/drivers/md/dm-snap.c 2019-10-01 15:19:20.000000000 > +0200 > +++ linux-2.6/drivers/md/dm-snap.c 2019-10-01 15:23:10.000000000 +0200 > @@ -1512,6 +1512,16 @@ static void snapshot_dtr(struct dm_targe > kfree(s); > } > > +static void account_start_copy(struct dm_snapshot *s) > +{ > + down(&s->cow_count); > +} > + > +static void account_end_copy(struct dm_snapshot *s) > +{ > + up(&s->cow_count); > +} > + > /* > * Flush a list of buffers. > */ > @@ -1732,7 +1742,7 @@ static void copy_callback(int read_err, > rb_link_node(&pe->out_of_order_node, parent, p); > rb_insert_color(&pe->out_of_order_node, &s->out_of_order_tree); > } > - up(&s->cow_count); > + account_end_copy(s); > } > > /* > @@ -1756,7 +1766,7 @@ static void start_copy(struct dm_snap_pe > dest.count = src.count; > > /* Hand over to kcopyd */ > - down(&s->cow_count); > + account_start_copy(s); > dm_kcopyd_copy(s->kcopyd_client, &src, 1, &dest, 0, copy_callback, pe); > } > > @@ -1776,7 +1786,7 @@ static void start_full_bio(struct dm_sna > pe->full_bio = bio; > pe->full_bio_end_io = bio->bi_end_io; > > - down(&s->cow_count); > + account_start_copy(s); > callback_data = dm_kcopyd_prepare_callback(s->kcopyd_client, > copy_callback, pe); > > @@ -1866,7 +1876,7 @@ static void zero_callback(int read_err, > struct bio *bio = context; > struct dm_snapshot *s = bio->bi_private; > > - up(&s->cow_count); > + account_end_copy(s); > bio->bi_status = write_err ? BLK_STS_IOERR : 0; > bio_endio(bio); > } > @@ -1880,7 +1890,7 @@ static void zero_exception(struct dm_sna > dest.sector = bio->bi_iter.bi_sector; > dest.count = s->store->chunk_size; > > - down(&s->cow_count); > + account_start_copy(s); > WARN_ON_ONCE(bio->bi_private); > bio->bi_private = s; > dm_kcopyd_zero(s->kcopyd_client, 1, &dest, 0, zero_callback, bio); > -- dm-devel mailing list [email protected] https://www.redhat.com/mailman/listinfo/dm-devel
