diff options
| author | Javier González <javier@cnexlabs.com> | 2017-10-13 14:46:17 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2017-10-13 08:34:57 -0600 |
| commit | 6ca2f71f3e3d94d188000b420ce0529b07f3ce95 (patch) | |
| tree | e99c846fd3bbbd5786e41425371584763abe0d0a | |
| parent | 55e836d401601e7903b36db015ce899dc11085ab (diff) | |
| download | blackbird-obmc-linux-6ca2f71f3e3d94d188000b420ce0529b07f3ce95.tar.gz blackbird-obmc-linux-6ca2f71f3e3d94d188000b420ce0529b07f3ce95.zip | |
lightnvm: pblk: simplify path on REQ_PREFLUSH
On REQ_PREFLUSH, directly tag the I/O context flags to signal a flush in
the write to cache path, instead of finding the correct entry context
and imposing a memory barrier. This simplifies the code and might
potentially prevent race conditions when adding functionality to the
write path.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | drivers/lightnvm/pblk-cache.c | 4 | ||||
| -rw-r--r-- | drivers/lightnvm/pblk-rb.c | 8 |
2 files changed, 4 insertions, 8 deletions
diff --git a/drivers/lightnvm/pblk-cache.c b/drivers/lightnvm/pblk-cache.c index 1d6b8e3585f1..0d227ef7d1b9 100644 --- a/drivers/lightnvm/pblk-cache.c +++ b/drivers/lightnvm/pblk-cache.c @@ -43,8 +43,10 @@ retry: if (unlikely(!bio_has_data(bio))) goto out; - w_ctx.flags = flags; pblk_ppa_set_empty(&w_ctx.ppa); + w_ctx.flags = flags; + if (bio->bi_opf & REQ_PREFLUSH) + w_ctx.flags |= PBLK_FLUSH_ENTRY; for (i = 0; i < nr_entries; i++) { void *data = bio_data(bio); diff --git a/drivers/lightnvm/pblk-rb.c b/drivers/lightnvm/pblk-rb.c index 74c768ce09ef..05e6b2e9221d 100644 --- a/drivers/lightnvm/pblk-rb.c +++ b/drivers/lightnvm/pblk-rb.c @@ -355,7 +355,6 @@ static int pblk_rb_sync_point_set(struct pblk_rb *rb, struct bio *bio, { struct pblk_rb_entry *entry; unsigned int subm, sync_point; - int flags; subm = READ_ONCE(rb->subm); @@ -369,12 +368,6 @@ static int pblk_rb_sync_point_set(struct pblk_rb *rb, struct bio *bio, sync_point = (pos == 0) ? (rb->nr_entries - 1) : (pos - 1); entry = &rb->entries[sync_point]; - flags = READ_ONCE(entry->w_ctx.flags); - flags |= PBLK_FLUSH_ENTRY; - - /* Release flags on context. Protect from writes */ - smp_store_release(&entry->w_ctx.flags, flags); - /* Protect syncs */ smp_store_release(&rb->sync_point, sync_point); @@ -454,6 +447,7 @@ static int pblk_rb_may_write_flush(struct pblk_rb *rb, unsigned int nr_entries, /* Protect from read count */ smp_store_release(&rb->mem, mem); + return 1; } |
