diff options
| author | Kairui Song <kasong@tencent.com> | 2025-09-17 00:00:52 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2025-09-21 14:22:23 -0700 |
| commit | 0fcf8ef4fdab8e5c91d1bce39c7fe6565974ffad (patch) | |
| tree | 6bf00db454b02ef68dbef708cfd820a4a6eecf2b /mm/swap_state.c | |
| parent | 4522aed4fffbbd18ab3581d733d0572d45780d07 (diff) | |
mm, swap: tidy up swap device and cluster info helpers
swp_swap_info is the most commonly used helper for retrieving swap info.
It has an internal check that may lead to a NULL return value, but almost
none of its caller checks the return value, making the internal check
pointless. In fact, most of these callers already ensured the entry is
valid and never expect a NULL value.
Tidy this up and improve the function names. If the caller can make sure
the swap entry/type is valid and the device is pinned, use the new
introduced __swap_entry_to_info/__swap_type_to_info instead. They have
more debug sanity checks and lower overhead as they are inlined.
Callers that may expect a NULL value should use
swap_entry_to_info/swap_type_to_info instead.
No feature change. The rearranged codes should have had no effect, or
they should have been hitting NULL de-ref bugs already. Only some new
sanity checks are added so potential issues may show up in debug build.
The new helpers will be frequently used with swap table later when working
with swap cache folios. A locked swap cache folio ensures the entries are
valid and stable so these helpers are very helpful.
Link: https://lkml.kernel.org/r/20250916160100.31545-8-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Acked-by: Chris Li <chrisl@kernel.org>
Reviewed-by: Barry Song <baohua@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Suggested-by: Chris Li <chrisl@kernel.org>
Cc: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: "Huang, Ying" <ying.huang@linux.alibaba.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: kernel test robot <oliver.sang@intel.com>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: SeongJae Park <sj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'mm/swap_state.c')
| -rw-r--r-- | mm/swap_state.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/mm/swap_state.c b/mm/swap_state.c index 9225d6b695ad..0ad4f3b41f1b 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -336,7 +336,7 @@ struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, struct mempolicy *mpol, pgoff_t ilx, bool *new_page_allocated, bool skip_if_exists) { - struct swap_info_struct *si = swp_swap_info(entry); + struct swap_info_struct *si = __swap_entry_to_info(entry); struct folio *folio; struct folio *new_folio = NULL; struct folio *result = NULL; @@ -560,7 +560,7 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, unsigned long offset = entry_offset; unsigned long start_offset, end_offset; unsigned long mask; - struct swap_info_struct *si = swp_swap_info(entry); + struct swap_info_struct *si = __swap_entry_to_info(entry); struct blk_plug plug; struct swap_iocb *splug = NULL; bool page_allocated; |