2020-08-10 10:41:00

by Chao Yu

[permalink] [raw]
Subject: [PATCH] f2fs: compress: use more readable atomic_t type for {cic,dic}.ref

refcount_t type variable should never be less than one, so it's a
little bit hard to understand when we use it to indicate pending
compressed page count, let's change to use atomic_t for better
readability.

Signed-off-by: Chao Yu <[email protected]>
---
fs/f2fs/compress.c | 10 +++++-----
fs/f2fs/data.c | 6 +++---
fs/f2fs/f2fs.h | 4 ++--
3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/fs/f2fs/compress.c b/fs/f2fs/compress.c
index 3bb112e91cf6..38eb6707f883 100644
--- a/fs/f2fs/compress.c
+++ b/fs/f2fs/compress.c
@@ -677,7 +677,7 @@ void f2fs_decompress_pages(struct bio *bio, struct page *page, bool verity)
if (bio->bi_status || PageError(page))
dic->failed = true;

- if (refcount_dec_not_one(&dic->ref))
+ if (atomic_dec_return(&dic->pending_pages))
return;

trace_f2fs_decompress_pages_start(dic->inode, dic->cluster_idx,
@@ -746,7 +746,7 @@ void f2fs_decompress_pages(struct bio *bio, struct page *page, bool verity)
cops->destroy_decompress_ctx(dic);
out_free_dic:
if (verity)
- refcount_set(&dic->ref, dic->nr_cpages);
+ atomic_set(&dic->pending_pages, dic->nr_cpages);
if (!verity)
f2fs_decompress_end_io(dic->rpages, dic->cluster_size,
ret, false);
@@ -1161,7 +1161,7 @@ static int f2fs_write_compressed_pages(struct compress_ctx *cc,

cic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
cic->inode = inode;
- refcount_set(&cic->ref, cc->nr_cpages);
+ atomic_set(&cic->pending_pages, cc->nr_cpages);
cic->rpages = f2fs_kzalloc(sbi, sizeof(struct page *) <<
cc->log_cluster_size, GFP_NOFS);
if (!cic->rpages)
@@ -1296,7 +1296,7 @@ void f2fs_compress_write_end_io(struct bio *bio, struct page *page)

dec_page_count(sbi, F2FS_WB_DATA);

- if (refcount_dec_not_one(&cic->ref))
+ if (atomic_dec_return(&cic->pending_pages))
return;

for (i = 0; i < cic->nr_rpages; i++) {
@@ -1438,7 +1438,7 @@ struct decompress_io_ctx *f2fs_alloc_dic(struct compress_ctx *cc)

dic->magic = F2FS_COMPRESSED_PAGE_MAGIC;
dic->inode = cc->inode;
- refcount_set(&dic->ref, cc->nr_cpages);
+ atomic_set(&dic->pending_pages, cc->nr_cpages);
dic->cluster_idx = cc->cluster_idx;
dic->cluster_size = cc->cluster_size;
dic->log_cluster_size = cc->log_cluster_size;
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index c1b676be67b9..024e1695ae66 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -201,7 +201,7 @@ static void f2fs_verify_bio(struct bio *bio)
dic = (struct decompress_io_ctx *)page_private(page);

if (dic) {
- if (refcount_dec_not_one(&dic->ref))
+ if (atomic_dec_return(&dic->pending_pages))
continue;
f2fs_verify_pages(dic->rpages,
dic->cluster_size);
@@ -2222,8 +2222,8 @@ int f2fs_read_multi_pages(struct compress_ctx *cc, struct bio **bio_ret,
if (IS_ERR(bio)) {
ret = PTR_ERR(bio);
dic->failed = true;
- if (refcount_sub_and_test(dic->nr_cpages - i,
- &dic->ref)) {
+ if (!atomic_sub_return(dic->nr_cpages - i,
+ &dic->pending_pages)) {
f2fs_decompress_end_io(dic->rpages,
cc->cluster_size, true,
false);
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 16322ea5b463..61da996ea4cc 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1366,7 +1366,7 @@ struct compress_io_ctx {
struct inode *inode; /* inode the context belong to */
struct page **rpages; /* pages store raw data in cluster */
unsigned int nr_rpages; /* total page number in rpages */
- refcount_t ref; /* referrence count of raw page */
+ atomic_t pending_pages; /* in-flight compressed page count */
};

/* decompress io context for read IO path */
@@ -1385,7 +1385,7 @@ struct decompress_io_ctx {
struct compress_data *cbuf; /* virtual mapped address on cpages */
size_t rlen; /* valid data length in rbuf */
size_t clen; /* valid data length in cbuf */
- refcount_t ref; /* referrence count of compressed page */
+ atomic_t pending_pages; /* in-flight compressed page count */
bool failed; /* indicate IO error during decompression */
void *private; /* payload buffer for specified decompression algorithm */
void *private2; /* extra payload buffer */
--
2.26.2