From b2d1f38b524121130befa3a9b37dca790cfa9ab9 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed Date: Fri, 7 Jun 2024 04:55:15 +0000 Subject: [PATCH] mm: swap: remove 'synchronous' argument to swap_read_folio() Commit [1] introduced IO polling support duding swapin to reduce swap read latency for block devices that can be polled. However later commit [2] removed polling support. Commit [3] removed the remnants of polling support from read_swap_cache_async() and __read_swap_cache_async(). However, it left behind some remnants in swap_read_folio(), the 'synchronous' argument. swap_read_folio() reads the folio synchronously if synchronous=true or if SWP_SYNCHRONOUS_IO is set in swap_info_struct. The only caller that passes synchronous=true is in do_swap_page() in the SWP_SYNCHRONOUS_IO case. Hence, the argument is redundant, it is only set to true when the swap read would have been synchronous anyway. Remove it. [1] Commit 23955622ff8d ("swap: add block io poll in swapin path") [2] Commit 9650b453a3d4 ("block: ignore RWF_HIPRI hint for sync dio") [3] Commit b243dcbf2f13 ("swap: remove remnants of polling from read_swap_cache_async") Link: https://lkml.kernel.org/r/20240607045515.1836558-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed Reviewed-by: "Huang, Ying" Reviewed-by: Christoph Hellwig Signed-off-by: Andrew Morton --- mm/memory.c | 2 +- mm/page_io.c | 6 +++--- mm/swap.h | 6 ++---- mm/swap_state.c | 10 +++++----- 4 files changed, 11 insertions(+), 13 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index edd987f1bd8c..44a81d737f1e 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -4115,7 +4115,7 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) /* To provide entry to swap_read_folio() */ folio->swap = entry; - swap_read_folio(folio, true, NULL); + swap_read_folio(folio, NULL); folio->private = NULL; } } else { diff --git a/mm/page_io.c b/mm/page_io.c index 41e8d738c6d2..f1a9cfab6e74 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -493,10 +493,10 @@ static void swap_read_folio_bdev_async(struct folio *folio, submit_bio(bio); } -void swap_read_folio(struct folio *folio, bool synchronous, - struct swap_iocb **plug) +void swap_read_folio(struct folio *folio, struct swap_iocb **plug) { struct swap_info_struct *sis = swp_swap_info(folio->swap); + bool synchronous = sis->flags & SWP_SYNCHRONOUS_IO; bool workingset = folio_test_workingset(folio); unsigned long pflags; bool in_thrashing; @@ -521,7 +521,7 @@ void swap_read_folio(struct folio *folio, bool synchronous, folio_unlock(folio); } else if (data_race(sis->flags & SWP_FS_OPS)) { swap_read_folio_fs(folio, plug); - } else if (synchronous || (sis->flags & SWP_SYNCHRONOUS_IO)) { + } else if (synchronous) { swap_read_folio_bdev_sync(folio, sis); } else { swap_read_folio_bdev_async(folio, sis); diff --git a/mm/swap.h b/mm/swap.h index 2c0e96272d49..baa1fa946b34 100644 --- a/mm/swap.h +++ b/mm/swap.h @@ -11,8 +11,7 @@ struct mempolicy; /* linux/mm/page_io.c */ int sio_pool_init(void); struct swap_iocb; -void swap_read_folio(struct folio *folio, bool do_poll, - struct swap_iocb **plug); +void swap_read_folio(struct folio *folio, struct swap_iocb **plug); void __swap_read_unplug(struct swap_iocb *plug); static inline void swap_read_unplug(struct swap_iocb *plug) { @@ -83,8 +82,7 @@ static inline unsigned int folio_swap_flags(struct folio *folio) } #else /* CONFIG_SWAP */ struct swap_iocb; -static inline void swap_read_folio(struct folio *folio, bool do_poll, - struct swap_iocb **plug) +static inline void swap_read_folio(struct folio *folio, struct swap_iocb **plug) { } static inline void swap_write_unplug(struct swap_iocb *sio) diff --git a/mm/swap_state.c b/mm/swap_state.c index 0803eedeabe3..994723cef821 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -567,7 +567,7 @@ struct folio *read_swap_cache_async(swp_entry_t entry, gfp_t gfp_mask, mpol_cond_put(mpol); if (page_allocated) - swap_read_folio(folio, false, plug); + swap_read_folio(folio, plug); return folio; } @@ -684,7 +684,7 @@ struct folio *swap_cluster_readahead(swp_entry_t entry, gfp_t gfp_mask, if (!folio) continue; if (page_allocated) { - swap_read_folio(folio, false, &splug); + swap_read_folio(folio, &splug); if (offset != entry_offset) { folio_set_readahead(folio); count_vm_event(SWAP_RA); @@ -701,7 +701,7 @@ skip: &page_allocated, false); if (unlikely(page_allocated)) { zswap_folio_swapin(folio); - swap_read_folio(folio, false, NULL); + swap_read_folio(folio, NULL); } return folio; } @@ -834,7 +834,7 @@ static struct folio *swap_vma_readahead(swp_entry_t targ_entry, gfp_t gfp_mask, if (!folio) continue; if (page_allocated) { - swap_read_folio(folio, false, &splug); + swap_read_folio(folio, &splug); if (addr != vmf->address) { folio_set_readahead(folio); count_vm_event(SWAP_RA); @@ -853,7 +853,7 @@ skip: &page_allocated, false); if (unlikely(page_allocated)) { zswap_folio_swapin(folio); - swap_read_folio(folio, false, NULL); + swap_read_folio(folio, NULL); } return folio; }