diff options
Diffstat (limited to 'fs/erofs/zdata.c')
-rw-r--r-- | fs/erofs/zdata.c | 172 |
1 files changed, 99 insertions, 73 deletions
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index 86fd3bf62af6..6cb356c4217b 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -20,6 +20,11 @@ enum z_erofs_cache_alloctype { DONTALLOC, /* don't allocate any cached pages */ DELAYEDALLOC, /* delayed allocation (at the time of submitting io) */ + /* + * try to use cached I/O if page allocation succeeds or fallback + * to in-place I/O instead to avoid any direct reclaim. + */ + TRYALLOC, }; /* @@ -154,13 +159,16 @@ static DEFINE_MUTEX(z_pagemap_global_lock); static void preload_compressed_pages(struct z_erofs_collector *clt, struct address_space *mc, - enum z_erofs_cache_alloctype type) + enum z_erofs_cache_alloctype type, + struct list_head *pagepool) { const struct z_erofs_pcluster *pcl = clt->pcl; const unsigned int clusterpages = BIT(pcl->clusterbits); struct page **pages = clt->compressedpages; pgoff_t index = pcl->obj.index + (pages - pcl->compressed_pages); bool standalone = true; + gfp_t gfp = (mapping_gfp_mask(mc) & ~__GFP_DIRECT_RECLAIM) | + __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN; if (clt->mode < COLLECT_PRIMARY_FOLLOWED) return; @@ -168,6 +176,7 @@ static void preload_compressed_pages(struct z_erofs_collector *clt, for (; pages < pcl->compressed_pages + clusterpages; ++pages) { struct page *page; compressed_page_t t; + struct page *newpage = NULL; /* the compressed page was loaded before */ if (READ_ONCE(*pages)) @@ -179,7 +188,15 @@ static void preload_compressed_pages(struct z_erofs_collector *clt, t = tag_compressed_page_justfound(page); } else if (type == DELAYEDALLOC) { t = tagptr_init(compressed_page_t, PAGE_UNALLOCATED); + } else if (type == TRYALLOC) { + newpage = erofs_allocpage(pagepool, gfp); + if (!newpage) + goto dontalloc; + + set_page_private(newpage, Z_EROFS_PREALLOCATED_PAGE); + t = tag_compressed_page_justfound(newpage); } else { /* DONTALLOC */ +dontalloc: if (standalone) clt->compressedpages = pages; standalone = false; @@ -189,8 +206,12 @@ static void preload_compressed_pages(struct z_erofs_collector *clt, if (!cmpxchg_relaxed(pages, NULL, tagptr_cast_ptr(t))) continue; - if (page) + if (page) { put_page(page); + } else if (newpage) { + set_page_private(newpage, 0); + list_add(&newpage->lru, pagepool); + } } if (standalone) /* downgrade to PRIMARY_FOLLOWED_NOINPLACE */ @@ -226,11 +247,8 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, /* barrier is implied in the following 'unlock_page' */ WRITE_ONCE(pcl->compressed_pages[i], NULL); - set_page_private(page, 0); - ClearPagePrivate(page); - + detach_page_private(page); unlock_page(page); - put_page(page); } return 0; } @@ -254,10 +272,8 @@ int erofs_try_to_free_cached_page(struct address_space *mapping, } erofs_workgroup_unfreeze(&pcl->obj, 1); - if (ret) { - ClearPagePrivate(page); - put_page(page); - } + if (ret) + detach_page_private(page); } return ret; } @@ -297,34 +313,33 @@ static int z_erofs_attach_page(struct z_erofs_collector *clt, return ret ? 0 : -EAGAIN; } -static enum z_erofs_collectmode -try_to_claim_pcluster(struct z_erofs_pcluster *pcl, - z_erofs_next_pcluster_t *owned_head) +static void z_erofs_try_to_claim_pcluster(struct z_erofs_collector *clt) { - /* let's claim these following types of pclusters */ -retry: - if (pcl->next == Z_EROFS_PCLUSTER_NIL) { - /* type 1, nil pcluster */ - if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_NIL, - *owned_head) != Z_EROFS_PCLUSTER_NIL) - goto retry; + struct z_erofs_pcluster *pcl = clt->pcl; + z_erofs_next_pcluster_t *owned_head = &clt->owned_head; + /* type 1, nil pcluster (this pcluster doesn't belong to any chain.) */ + if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_NIL, + *owned_head) == Z_EROFS_PCLUSTER_NIL) { *owned_head = &pcl->next; - /* lucky, I am the followee :) */ - return COLLECT_PRIMARY_FOLLOWED; - } else if (pcl->next == Z_EROFS_PCLUSTER_TAIL) { - /* - * type 2, link to the end of a existing open chain, - * be careful that its submission itself is governed - * by the original owned chain. - */ - if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_TAIL, - *owned_head) != Z_EROFS_PCLUSTER_TAIL) - goto retry; + /* so we can attach this pcluster to our submission chain. */ + clt->mode = COLLECT_PRIMARY_FOLLOWED; + return; + } + + /* + * type 2, link to the end of an existing open chain, be careful + * that its submission is controlled by the original attached chain. + */ + if (cmpxchg(&pcl->next, Z_EROFS_PCLUSTER_TAIL, + *owned_head) == Z_EROFS_PCLUSTER_TAIL) { *owned_head = Z_EROFS_PCLUSTER_TAIL; - return COLLECT_PRIMARY_HOOKED; + clt->mode = COLLECT_PRIMARY_HOOKED; + clt->tailpcl = NULL; + return; } - return COLLECT_PRIMARY; /* :( better luck next time */ + /* type 3, it belongs to a chain, but it isn't the end of the chain */ + clt->mode = COLLECT_PRIMARY; } static int z_erofs_lookup_collection(struct z_erofs_collector *clt, @@ -369,10 +384,8 @@ static int z_erofs_lookup_collection(struct z_erofs_collector *clt, /* used to check tail merging loop due to corrupted images */ if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL) clt->tailpcl = pcl; - clt->mode = try_to_claim_pcluster(pcl, &clt->owned_head); - /* clean tailpcl if the current owned_head is Z_EROFS_PCLUSTER_TAIL */ - if (clt->owned_head == Z_EROFS_PCLUSTER_TAIL) - clt->tailpcl = NULL; + + z_erofs_try_to_claim_pcluster(clt); clt->cl = cl; return 0; } @@ -562,7 +575,7 @@ static bool should_alloc_managed_pages(struct z_erofs_decompress_frontend *fe, } static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe, - struct page *page) + struct page *page, struct list_head *pagepool) { struct inode *const inode = fe->inode; struct erofs_sb_info *const sbi = EROFS_I_SB(inode); @@ -615,11 +628,12 @@ restart_now: /* preload all compressed pages (maybe downgrade role if necessary) */ if (should_alloc_managed_pages(fe, sbi->ctx.cache_strategy, map->m_la)) - cache_strategy = DELAYEDALLOC; + cache_strategy = TRYALLOC; else cache_strategy = DONTALLOC; - preload_compressed_pages(clt, MNGD_MAPPING(sbi), cache_strategy); + preload_compressed_pages(clt, MNGD_MAPPING(sbi), + cache_strategy, pagepool); hitted: /* @@ -648,12 +662,12 @@ hitted: retry: err = z_erofs_attach_page(clt, page, page_type); - /* should allocate an additional staging page for pagevec */ + /* should allocate an additional short-lived page for pagevec */ if (err == -EAGAIN) { struct page *const newpage = alloc_page(GFP_NOFS | __GFP_NOFAIL); - newpage->mapping = Z_EROFS_MAPPING_STAGING; + set_page_private(newpage, Z_EROFS_SHORTLIVED_PAGE); err = z_erofs_attach_page(clt, newpage, Z_EROFS_PAGE_TYPE_EXCLUSIVE); if (!err) @@ -710,6 +724,11 @@ static void z_erofs_decompress_kickoff(struct z_erofs_decompressqueue *io, queue_work(z_erofs_workqueue, &io->u.work); } +static bool z_erofs_page_is_invalidated(struct page *page) +{ + return !page->mapping && !z_erofs_is_shortlived_page(page); +} + static void z_erofs_decompressqueue_endio(struct bio *bio) { tagptr1_t t = tagptr_init(tagptr1_t, bio->bi_private); @@ -722,7 +741,7 @@ static void z_erofs_decompressqueue_endio(struct bio *bio) struct page *page = bvec->bv_page; DBG_BUGON(PageUptodate(page)); - DBG_BUGON(!page->mapping); + DBG_BUGON(z_erofs_page_is_invalidated(page)); if (err) SetPageError(page); @@ -795,9 +814,9 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, /* all pages in pagevec ought to be valid */ DBG_BUGON(!page); - DBG_BUGON(!page->mapping); + DBG_BUGON(z_erofs_page_is_invalidated(page)); - if (z_erofs_put_stagingpage(pagepool, page)) + if (z_erofs_put_shortlivedpage(pagepool, page)) continue; if (page_type == Z_EROFS_VLE_PAGE_TYPE_HEAD) @@ -831,9 +850,9 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, /* all compressed pages ought to be valid */ DBG_BUGON(!page); - DBG_BUGON(!page->mapping); + DBG_BUGON(z_erofs_page_is_invalidated(page)); - if (!z_erofs_page_is_staging(page)) { + if (!z_erofs_is_shortlived_page(page)) { if (erofs_page_is_managed(sbi, page)) { if (!PageUptodate(page)) err = -EIO; @@ -858,7 +877,7 @@ static int z_erofs_decompress_pcluster(struct super_block *sb, overlapped = true; } - /* PG_error needs checking for inplaced and staging pages */ + /* PG_error needs checking for all non-managed pages */ if (PageError(page)) { DBG_BUGON(PageUptodate(page)); err = -EIO; @@ -897,8 +916,8 @@ out: if (erofs_page_is_managed(sbi, page)) continue; - /* recycle all individual staging pages */ - (void)z_erofs_put_stagingpage(pagepool, page); + /* recycle all individual short-lived pages */ + (void)z_erofs_put_shortlivedpage(pagepool, page); WRITE_ONCE(compressed_pages[i], NULL); } @@ -908,10 +927,10 @@ out: if (!page) continue; - DBG_BUGON(!page->mapping); + DBG_BUGON(z_erofs_page_is_invalidated(page)); - /* recycle all individual staging pages */ - if (z_erofs_put_stagingpage(pagepool, page)) + /* recycle all individual short-lived pages */ + if (z_erofs_put_shortlivedpage(pagepool, page)) continue; if (err < 0) @@ -1008,16 +1027,30 @@ repeat: justfound = tagptr_unfold_tags(t); page = tagptr_unfold_ptr(t); + /* + * preallocated cached pages, which is used to avoid direct reclaim + * otherwise, it will go inplace I/O path instead. + */ + if (page->private == Z_EROFS_PREALLOCATED_PAGE) { + WRITE_ONCE(pcl->compressed_pages[nr], page); + set_page_private(page, 0); + tocache = true; + goto out_tocache; + } mapping = READ_ONCE(page->mapping); /* - * unmanaged (file) pages are all locked solidly, + * file-backed online pages in plcuster are all locked steady, * therefore it is impossible for `mapping' to be NULL. */ if (mapping && mapping != mc) /* ought to be unmanaged pages */ goto out; + /* directly return for shortlived page as well */ + if (z_erofs_is_shortlived_page(page)) + goto out; + lock_page(page); /* only true if page reclaim goes wrong, should never happen */ @@ -1061,28 +1094,21 @@ repeat: put_page(page); out_allocpage: page = erofs_allocpage(pagepool, gfp | __GFP_NOFAIL); - if (!tocache || add_to_page_cache_lru(page, mc, index + nr, gfp)) { - /* non-LRU / non-movable temporary page is needed */ - page->mapping = Z_EROFS_MAPPING_STAGING; - tocache = false; - } - if (oldpage != cmpxchg(&pcl->compressed_pages[nr], oldpage, page)) { - if (tocache) { - /* since it added to managed cache successfully */ - unlock_page(page); - put_page(page); - } else { - list_add(&page->lru, pagepool); - } + list_add(&page->lru, pagepool); cond_resched(); goto repeat; } - - if (tocache) { - set_page_private(page, (unsigned long)pcl); - SetPagePrivate(page); +out_tocache: + if (!tocache || add_to_page_cache_lru(page, mc, index + nr, gfp)) { + /* turn into temporary page if fails (1 ref) */ + set_page_private(page, Z_EROFS_SHORTLIVED_PAGE); + goto out; } + attach_page_private(page, pcl); + /* drop a refcount added by allocpage (then we have 2 refs here) */ + put_page(page); + out: /* the only exit (for tracing and debugging) */ return page; } @@ -1284,7 +1310,7 @@ static int z_erofs_readpage(struct file *file, struct page *page) f.headoffset = (erofs_off_t)page->index << PAGE_SHIFT; - err = z_erofs_do_read_page(&f, page); + err = z_erofs_do_read_page(&f, page, &pagepool); (void)z_erofs_collector_end(&f.clt); /* if some compressed cluster ready, need submit them anyway */ @@ -1338,7 +1364,7 @@ static void z_erofs_readahead(struct readahead_control *rac) /* traversal in reverse order */ head = (void *)page_private(page); - err = z_erofs_do_read_page(&f, page); + err = z_erofs_do_read_page(&f, page, &pagepool); if (err) erofs_err(inode->i_sb, "readahead error at page %lu @ nid %llu", |