| Message ID | 20230529061355.125791-5-ying.huang@intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | swap: cleanup get/put_swap_device() usage | expand |
On 29.05.23 08:13, Huang Ying wrote: > __swap_duplicate() is called by > > - swap_shmem_alloc(): the folio in swap cache is locked. > > - copy_nonpresent_pte() -> swap_duplicate() and try_to_unmap_one() -> > swap_duplicate(): the page table lock is held. > > - __read_swap_cache_async() -> swapcache_prepare(): enclosed with > get/put_swap_device() in __read_swap_cache_async() already. > > So, it's safe to remove get/put_swap_device() in __swap_duplicate(). > > Signed-off-by: "Huang, Ying" <ying.huang@intel.com> > Reviewed-by: Yosry Ahmed <yosryahmed@google.com> > Cc: David Hildenbrand <david@redhat.com> > Cc: Hugh Dickins <hughd@google.com> > Cc: Johannes Weiner <hannes@cmpxchg.org> > Cc: Matthew Wilcox <willy@infradead.org> > Cc: Michal Hocko <mhocko@suse.com> > Cc: Minchan Kim <minchan@kernel.org> > Cc: Tim Chen <tim.c.chen@linux.intel.com> > Cc: Yang Shi <shy828301@gmail.com> > Cc: Yu Zhao <yuzhao@google.com> > Cc: Chris Li <chrisl@kernel.org> > --- Reviewed-by: David Hildenbrand <david@redhat.com>
diff --git a/mm/swapfile.c b/mm/swapfile.c index e9cce775fb25..4dbaea64635d 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -3264,9 +3264,7 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) unsigned char has_cache; int err; - p = get_swap_device(entry); - if (!p) - return -EINVAL; + p = swp_swap_info(entry); offset = swp_offset(entry); ci = lock_cluster_or_swap_info(p, offset); @@ -3313,7 +3311,6 @@ static int __swap_duplicate(swp_entry_t entry, unsigned char usage) unlock_out: unlock_cluster_or_swap_info(p, ci); - put_swap_device(p); return err; }