diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/memory.c | 6 | ||||
| -rw-r--r-- | mm/mincore.c | 3 | ||||
| -rw-r--r-- | mm/shmem.c | 4 | ||||
| -rw-r--r-- | mm/swap.h | 13 | ||||
| -rw-r--r-- | mm/swap_state.c | 109 | ||||
| -rw-r--r-- | mm/swapfile.c | 11 | ||||
| -rw-r--r-- | mm/userfaultfd.c | 5 |
7 files changed, 81 insertions, 70 deletions
diff --git a/mm/memory.c b/mm/memory.c index d9de6c056179..10ef528a5f44 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4660,9 +4660,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) if (unlikely(!si)) goto out; - folio = swap_cache_get_folio(entry, vma, vmf->address); - if (folio) + folio = swap_cache_get_folio(entry); + if (folio) { + swap_update_readahead(folio, vma, vmf->address); page = folio_file_page(folio, swp_offset(entry)); + } swapcache = folio; if (!folio) { diff --git a/mm/mincore.c b/mm/mincore.c index 2f3e1816a30d..8ec4719370e1 100644 --- a/mm/mincore.c +++ b/mm/mincore.c @@ -76,8 +76,7 @@ static unsigned char mincore_swap(swp_entry_t entry, bool shmem) if (!si) return 0; } - folio = filemap_get_entry(swap_address_space(entry), - swap_cache_index(entry)); + folio = swap_cache_get_folio(entry); if (shmem) put_swap_device(si); /* The swap cache space contains either folio, shadow or NULL */ diff --git a/mm/shmem.c b/mm/shmem.c index 29e1eb690125..410f27bc4752 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2317,7 +2317,7 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index, } /* Look it up and read it in.. */ - folio = swap_cache_get_folio(swap, NULL, 0); + folio = swap_cache_get_folio(swap); if (!folio) { if (data_race(si->flags & SWP_SYNCHRONOUS_IO)) { /* Direct swapin skipping swap cache & readahead */ @@ -2342,6 +2342,8 @@ static int shmem_swapin_folio(struct inode *inode, pgoff_t index, count_vm_event(PGMAJFAULT); count_memcg_event_mm(fault_mm, PGMAJFAULT); } + } else { + swap_update_readahead(folio, NULL, 0); } if (order > folio_order(folio)) { diff --git a/mm/swap.h b/mm/swap.h index 1ae44d4193b1..efb6d7ff9f30 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -62,8 +62,7 @@ void delete_from_swap_cache(struct folio *folio); void clear_shadow_from_swap_cache(int type, unsigned long begin, unsigned long end); void swapcache_clear(struct swap_info_struct *si, swp_entry_t entry, int nr); -struct folio *swap_cache_get_folio(swp_entry_t entry, - struct vm_area_struct *vma, unsigned long addr); +struct folio *swap_cache_get_folio(swp_entry_t entry); struct folio *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, struct vm_area_struct *vma, unsigned long addr, struct swap_iocb **plug); @@ -74,6 +73,8 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t flag, struct mempolicy *mpol, pgoff_t ilx); struct folio *swapin_readahead(swp_entry_t entry, gfp_t flag, struct vm_fault *vmf); +void swap_update_readahead(struct folio *folio, struct vm_area_struct *vma, + unsigned long addr); static inline unsigned int folio_swap_flags(struct folio *folio) { @@ -159,6 +160,11 @@ static inline struct folio *swapin_readahead(swp_entry_t swp, gfp_t gfp_mask, return NULL; } +static inline void swap_update_readahead(struct folio *folio, + struct vm_area_struct *vma, unsigned long addr) +{ +} + static inline int swap_writeout(struct folio *folio, struct swap_iocb **swap_plug) { @@ -169,8 +175,7 @@ static inline void swapcache_clear(struct swap_info_struct *si, swp_entry_t entr { } -static inline struct folio *swap_cache_get_folio(swp_entry_t entry, - struct vm_area_struct *vma, unsigned long addr) +static inline struct folio *swap_cache_get_folio(swp_entry_t entry) { return NULL; } diff --git a/mm/swap_state.c b/mm/swap_state.c index 99513b74b5d8..68ec531d0f2b 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -69,6 +69,27 @@ void show_swap_cache_info(void) printk("Total swap = %lukB\n", K(total_swap_pages)); } +/** + * swap_cache_get_folio - Looks up a folio in the swap cache. + * @entry: swap entry used for the lookup. + * + * A found folio will be returned unlocked and with its refcount increased. + * + * Context: Caller must ensure @entry is valid and protect the swap device + * with reference count or locks. + * Return: Returns the found folio on success, NULL otherwise. The caller + * must lock and check if the folio still matches the swap entry before + * use. + */ +struct folio *swap_cache_get_folio(swp_entry_t entry) +{ + struct folio *folio = filemap_get_folio(swap_address_space(entry), + swap_cache_index(entry)); + if (IS_ERR(folio)) + return NULL; + return folio; +} + void *get_shadow_from_swap_cache(swp_entry_t entry) { struct address_space *address_space = swap_address_space(entry); @@ -272,55 +293,43 @@ static inline bool swap_use_vma_readahead(void) return READ_ONCE(enable_vma_readahead) && !atomic_read(&nr_rotate_swap); } -/* - * Lookup a swap entry in the swap cache. A found folio will be returned - * unlocked and with its refcount incremented - we rely on the kernel - * lock getting page table operations atomic even if we drop the folio - * lock before returning. - * - * Caller must lock the swap device or hold a reference to keep it valid. +/** + * swap_update_readahead - Update the readahead statistics of VMA or globally. + * @folio: the swap cache folio that just got hit. + * @vma: the VMA that should be updated, could be NULL for global update. + * @addr: the addr that triggered the swapin, ignored if @vma is NULL. */ -struct folio *swap_cache_get_folio(swp_entry_t entry, - struct vm_area_struct *vma, unsigned long addr) +void swap_update_readahead(struct folio *folio, struct vm_area_struct *vma, + unsigned long addr) { - struct folio *folio; - - folio = filemap_get_folio(swap_address_space(entry), swap_cache_index(entry)); - if (!IS_ERR(folio)) { - bool vma_ra = swap_use_vma_readahead(); - bool readahead; + bool readahead, vma_ra = swap_use_vma_readahead(); - /* - * At the moment, we don't support PG_readahead for anon THP - * so let's bail out rather than confusing the readahead stat. - */ - if (unlikely(folio_test_large(folio))) - return folio; - - readahead = folio_test_clear_readahead(folio); - if (vma && vma_ra) { - unsigned long ra_val; - int win, hits; - - ra_val = GET_SWAP_RA_VAL(vma); - win = SWAP_RA_WIN(ra_val); - hits = SWAP_RA_HITS(ra_val); - if (readahead) - hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX); - atomic_long_set(&vma->swap_readahead_info, - SWAP_RA_VAL(addr, win, hits)); - } - - if (readahead) { - count_vm_event(SWAP_RA_HIT); - if (!vma || !vma_ra) - atomic_inc(&swapin_readahead_hits); - } - } else { - folio = NULL; + /* + * At the moment, we don't support PG_readahead for anon THP + * so let's bail out rather than confusing the readahead stat. + */ + if (unlikely(folio_test_large(folio))) + return; + + readahead = folio_test_clear_readahead(folio); + if (vma && vma_ra) { + unsigned long ra_val; + int win, hits; + + ra_val = GET_SWAP_RA_VAL(vma); + win = SWAP_RA_WIN(ra_val); + hits = SWAP_RA_HITS(ra_val); + if (readahead) + hits = min_t(int, hits + 1, SWAP_RA_HITS_MAX); + atomic_long_set(&vma->swap_readahead_info, + SWAP_RA_VAL(addr, win, hits)); } - return folio; + if (readahead) { + count_vm_event(SWAP_RA_HIT); + if (!vma || !vma_ra) + atomic_inc(&swapin_readahead_hits); + } } struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, @@ -336,14 +345,10 @@ struct folio *__read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, *new_page_allocated = false; for (;;) { int err; - /* - * First check the swap cache. Since this is normally - * called after swap_cache_get_folio() failed, re-calling - * that would confuse statistics. - */ - folio = filemap_get_folio(swap_address_space(entry), - swap_cache_index(entry)); - if (!IS_ERR(folio)) + + /* Check the swap cache in case the folio is already there */ + folio = swap_cache_get_folio(entry); + if (folio) goto got_folio; /* diff --git a/mm/swapfile.c b/mm/swapfile.c index a7ffabbe65ef..4b8ab2cb49ca 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -213,15 +213,14 @@ static int __try_to_reclaim_swap(struct swap_info_struct *si, unsigned long offset, unsigned long flags) { swp_entry_t entry = swp_entry(si->type, offset); - struct address_space *address_space = swap_address_space(entry); struct swap_cluster_info *ci; struct folio *folio; int ret, nr_pages; bool need_reclaim; again: - folio = filemap_get_folio(address_space, swap_cache_index(entry)); - if (IS_ERR(folio)) + folio = swap_cache_get_folio(entry); + if (!folio) return 0; nr_pages = folio_nr_pages(folio); @@ -2131,7 +2130,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, pte_unmap(pte); pte = NULL; - folio = swap_cache_get_folio(entry, vma, addr); + folio = swap_cache_get_folio(entry); if (!folio) { struct vm_fault vmf = { .vma = vma, @@ -2357,8 +2356,8 @@ retry: (i = find_next_to_unuse(si, i)) != 0) { entry = swp_entry(type, i); - folio = filemap_get_folio(swap_address_space(entry), swap_cache_index(entry)); - if (IS_ERR(folio)) + folio = swap_cache_get_folio(entry); + if (!folio) continue; /* diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c index 50aaa8dcd24c..af61b95c89e4 100644 --- a/mm/userfaultfd.c +++ b/mm/userfaultfd.c @@ -1489,9 +1489,8 @@ retry: * separately to allow proper handling. */ if (!src_folio) - folio = filemap_get_folio(swap_address_space(entry), - swap_cache_index(entry)); - if (!IS_ERR_OR_NULL(folio)) { + folio = swap_cache_get_folio(entry); + if (folio) { if (folio_test_large(folio)) { ret = -EBUSY; folio_put(folio); |