diff --git a/mm/swapfile.c b/mm/swapfile.c index 668684dc9efa..4f4fc74239d6 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1463,25 +1463,10 @@ struct swap_info_struct *get_swap_device(swp_entry_t entry) return NULL; } -static unsigned char swap_entry_put(struct swap_info_struct *si, - swp_entry_t entry) -{ - struct swap_cluster_info *ci; - unsigned long offset = swp_offset(entry); - unsigned char usage; - - ci = lock_cluster(si, offset); - usage = swap_entry_put_locked(si, ci, entry, 1); - unlock_cluster(ci); - - return usage; -} - -static bool swap_entries_put_nr(struct swap_info_struct *si, - swp_entry_t entry, int nr) +static bool swap_entries_put_map(struct swap_info_struct *si, + swp_entry_t entry, int nr) { unsigned long offset = swp_offset(entry); - unsigned int type = swp_type(entry); struct swap_cluster_info *ci; bool has_cache = false; unsigned char count; @@ -1492,14 +1477,10 @@ static bool swap_entries_put_nr(struct swap_info_struct *si, count = swap_count(data_race(si->swap_map[offset])); if (count != 1 && count != SWAP_MAP_SHMEM) goto fallback; - /* cross into another cluster */ - if (nr > SWAPFILE_CLUSTER - offset % SWAPFILE_CLUSTER) - goto fallback; ci = lock_cluster(si, offset); if (!swap_is_last_map(si, offset, nr, &has_cache)) { - unlock_cluster(ci); - goto fallback; + goto locked_fallback; } if (!has_cache) swap_entries_free(si, ci, entry, nr); @@ -1511,15 +1492,34 @@ static bool swap_entries_put_nr(struct swap_info_struct *si, return has_cache; fallback: - for (i = 0; i < nr; i++) { - if (data_race(si->swap_map[offset + i])) { - count = swap_entry_put(si, swp_entry(type, offset + i)); - if (count == SWAP_HAS_CACHE) - has_cache = true; - } else { - WARN_ON_ONCE(1); - } + ci = lock_cluster(si, offset); +locked_fallback: + for (i = 0; i < nr; i++, entry.val++) { + count = swap_entry_put_locked(si, ci, entry, 1); + if (count == SWAP_HAS_CACHE) + has_cache = true; } + unlock_cluster(ci); + return has_cache; + +} + +static bool swap_entries_put_map_nr(struct swap_info_struct *si, + swp_entry_t entry, int nr) +{ + int cluster_nr, cluster_rest; + unsigned long offset = swp_offset(entry); + bool has_cache = false; + + cluster_rest = SWAPFILE_CLUSTER - offset % SWAPFILE_CLUSTER; + while (nr) { + cluster_nr = min(nr, cluster_rest); + has_cache |= swap_entries_put_map(si, entry, cluster_nr); + cluster_rest = SWAPFILE_CLUSTER; + nr -= cluster_nr; + entry.val += cluster_nr; + } + return has_cache; } @@ -1818,7 +1818,7 @@ void free_swap_and_cache_nr(swp_entry_t entry, int nr) /* * First free all entries in the range. */ - any_only_cache = swap_entries_put_nr(si, entry, nr); + any_only_cache = swap_entries_put_map_nr(si, entry, nr); /* * Short-circuit the below loop if none of the entries had their @@ -1828,13 +1828,7 @@ void free_swap_and_cache_nr(swp_entry_t entry, int nr) goto out; /* - * Now go back over the range trying to reclaim the swap cache. This is - * more efficient for large folios because we will only try to reclaim - * the swap once per folio in the common case. If we do - * swap_entry_put() and __try_to_reclaim_swap() in the same loop, the - * latter will get a reference and lock the folio for every individual - * page but will only succeed once the swap slot for every subpage is - * zero. + * Now go back over the range trying to reclaim the swap cache. */ for (offset = start_offset; offset < end_offset; offset += nr) { nr = 1;