diff options
| author | Christoph Hellwig <hch@lst.de> | 2022-09-15 10:41:58 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-09-20 08:24:38 -0600 |
| commit | 4088a47e78f95a5fea683cf67e0be006b13831fd (patch) | |
| tree | 08246485b7e6b1e1847ad759f7986625dca24f78 | |
| parent | 527eb453bbfe65e5a55a90edfb1f30b477e36b8c (diff) | |
btrfs: add manual PSI accounting for compressed reads
btrfs compressed reads try to always read the entire compressed chunk,
even if only a subset is requested. Currently this is covered by the
magic PSI accounting underneath submit_bio, but that is about to go
away. Instead add manual psi_memstall_{enter,leave} annotations.
Note that for readahead this really should be using readahead_expand,
but the additionals reads are also done for plain ->read_folio where
readahead_expand can't work, so this overall logic is left as-is for
now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/r/20220915094200.139713-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
| -rw-r--r-- | fs/btrfs/compression.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index e84d22c5c6a8..370788b9b124 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -15,6 +15,7 @@ #include <linux/string.h> #include <linux/backing-dev.h> #include <linux/writeback.h> +#include <linux/psi.h> #include <linux/slab.h> #include <linux/sched/mm.h> #include <linux/log2.h> @@ -519,7 +520,8 @@ static u64 bio_end_offset(struct bio *bio) */ static noinline int add_ra_bio_pages(struct inode *inode, u64 compressed_end, - struct compressed_bio *cb) + struct compressed_bio *cb, + unsigned long *pflags) { struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); unsigned long end_index; @@ -588,6 +590,9 @@ static noinline int add_ra_bio_pages(struct inode *inode, continue; } + if (PageWorkingset(page)) + psi_memstall_enter(pflags); + ret = set_page_extent_mapped(page); if (ret < 0) { unlock_page(page); @@ -674,6 +679,8 @@ void btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, u64 em_len; u64 em_start; struct extent_map *em; + /* Initialize to 1 to make skip psi_memstall_leave unless needed */ + unsigned long pflags = 1; blk_status_t ret; int ret2; int i; @@ -729,7 +736,7 @@ void btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, goto fail; } - add_ra_bio_pages(inode, em_start + em_len, cb); + add_ra_bio_pages(inode, em_start + em_len, cb, &pflags); /* include any pages we added in add_ra-bio_pages */ cb->len = bio->bi_iter.bi_size; @@ -810,6 +817,9 @@ void btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, } } + if (!pflags) + psi_memstall_leave(&pflags); + if (refcount_dec_and_test(&cb->pending_ios)) finish_compressed_bio_read(cb); return; |