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Diffstat (limited to 'fs/erofs/zdata.c')
-rw-r--r--fs/erofs/zdata.c172
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",