Message ID | 20200530091250.58420-1-yehs2007@zoho.com (mailing list archive) |
---|---|
State | Rejected, archived |
Delegated to: | Mike Snitzer |
Headers | show |
Series | dm writecache: reinitialize lru in writeback instead of endio | expand |
On Sat, 30 May 2020, Huaisheng Ye wrote: > From: Huaisheng Ye <yehs1@lenovo.com> > > When wc_entry has been removed from wbl->list in writeback, it will > be not used again except waiting to be set free in writecache_free_entry. > > That is a little of annoying, it has to reinitialize lru of wc_entry > in endio before calling writecache_free_entry. > > Using list_del_init instead of list_del in writeback for simpler code. > > Signed-off-by: Huaisheng Ye <yehs1@lenovo.com> This patch doesn't fix anything, so I think we don't need it. Actually, it's better to keep the list entry uninitialized, because it helps us catch bugs where this uninitialized list entry could be used improperly. Mikulas > --- > drivers/md/dm-writecache.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c > index 7bbc21b..66f3a3b 100644 > --- a/drivers/md/dm-writecache.c > +++ b/drivers/md/dm-writecache.c > @@ -1519,7 +1519,6 @@ static void __writecache_endio_pmem(struct dm_writecache *wc, struct list_head * > e = wb->wc_list[i]; > BUG_ON(!e->write_in_progress); > e->write_in_progress = false; > - INIT_LIST_HEAD(&e->lru); > if (!writecache_has_error(wc)) > writecache_free_entry(wc, e); > BUG_ON(!wc->writeback_size); > @@ -1555,7 +1554,6 @@ static void __writecache_endio_ssd(struct dm_writecache *wc, struct list_head *l > do { > BUG_ON(!e->write_in_progress); > e->write_in_progress = false; > - INIT_LIST_HEAD(&e->lru); > if (!writecache_has_error(wc)) > writecache_free_entry(wc, e); > > @@ -1654,7 +1652,7 @@ static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeba > while (wbl->size) { > wbl->size--; > e = container_of(wbl->list.prev, struct wc_entry, lru); > - list_del(&e->lru); > + list_del_init(&e->lru); > > max_pages = e->wc_list_contiguous; > > @@ -1685,7 +1683,7 @@ static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeba > if (!wc_add_block(wb, f, GFP_NOWAIT | __GFP_NOWARN)) > break; > wbl->size--; > - list_del(&f->lru); > + list_del_init(&f->lru); > wb->wc_list[wb->wc_list_n++] = f; > e = f; > } > @@ -1712,7 +1710,7 @@ static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writebac > > wbl->size--; > e = container_of(wbl->list.prev, struct wc_entry, lru); > - list_del(&e->lru); > + list_del_init(&e->lru); > > n_sectors = e->wc_list_contiguous << (wc->block_size_bits - SECTOR_SHIFT); > > @@ -1732,7 +1730,7 @@ static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writebac > wbl->size--; > f = container_of(wbl->list.prev, struct wc_entry, lru); > BUG_ON(f != e + 1); > - list_del(&f->lru); > + list_del_init(&f->lru); > e = f; > } > > -- > 1.8.3.1 > -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c index 7bbc21b..66f3a3b 100644 --- a/drivers/md/dm-writecache.c +++ b/drivers/md/dm-writecache.c @@ -1519,7 +1519,6 @@ static void __writecache_endio_pmem(struct dm_writecache *wc, struct list_head * e = wb->wc_list[i]; BUG_ON(!e->write_in_progress); e->write_in_progress = false; - INIT_LIST_HEAD(&e->lru); if (!writecache_has_error(wc)) writecache_free_entry(wc, e); BUG_ON(!wc->writeback_size); @@ -1555,7 +1554,6 @@ static void __writecache_endio_ssd(struct dm_writecache *wc, struct list_head *l do { BUG_ON(!e->write_in_progress); e->write_in_progress = false; - INIT_LIST_HEAD(&e->lru); if (!writecache_has_error(wc)) writecache_free_entry(wc, e); @@ -1654,7 +1652,7 @@ static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeba while (wbl->size) { wbl->size--; e = container_of(wbl->list.prev, struct wc_entry, lru); - list_del(&e->lru); + list_del_init(&e->lru); max_pages = e->wc_list_contiguous; @@ -1685,7 +1683,7 @@ static void __writecache_writeback_pmem(struct dm_writecache *wc, struct writeba if (!wc_add_block(wb, f, GFP_NOWAIT | __GFP_NOWARN)) break; wbl->size--; - list_del(&f->lru); + list_del_init(&f->lru); wb->wc_list[wb->wc_list_n++] = f; e = f; } @@ -1712,7 +1710,7 @@ static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writebac wbl->size--; e = container_of(wbl->list.prev, struct wc_entry, lru); - list_del(&e->lru); + list_del_init(&e->lru); n_sectors = e->wc_list_contiguous << (wc->block_size_bits - SECTOR_SHIFT); @@ -1732,7 +1730,7 @@ static void __writecache_writeback_ssd(struct dm_writecache *wc, struct writebac wbl->size--; f = container_of(wbl->list.prev, struct wc_entry, lru); BUG_ON(f != e + 1); - list_del(&f->lru); + list_del_init(&f->lru); e = f; }