diff options
| author | Christoph Hellwig <hch@lst.de> | 2025-02-24 15:48:54 -0800 |
|---|---|---|
| committer | Carlos Maiolino <cem@kernel.org> | 2025-02-25 13:05:59 +0100 |
| commit | 0d1120b9bbe48a2d119afe0dc64f9c0666745bc8 (patch) | |
| tree | 9aacd018c8475ddf5a93be7ee18f4cf1c627bb5e /fs/xfs/xfs_buf.h | |
| parent | efc5f7a9f3d887ce44b7610bc39388094b6f97d5 (diff) | |
xfs: remove most in-flight buffer accounting
The buffer cache keeps a bt_io_count per-CPU counter to track all
in-flight I/O, which is used to ensure no I/O is in flight when
unmounting the file system.
For most I/O we already keep track of inflight I/O at higher levels:
- for synchronous I/O (xfs_buf_read/xfs_bwrite/xfs_buf_delwri_submit),
the caller has a reference and waits for I/O completions using
xfs_buf_iowait
- for xfs_buf_delwri_submit_nowait the only caller (AIL writeback)
tracks the log items that the buffer attached to
This only leaves only xfs_buf_readahead_map as a submitter of
asynchronous I/O that is not tracked by anything else. Replace the
bt_io_count per-cpu counter with a more specific bt_readahead_count
counter only tracking readahead I/O. This allows to simply increment
it when submitting readahead I/O and decrementing it when it completed,
and thus simplify xfs_buf_rele and remove the needed for the
XBF_NO_IOACCT flags and the XFS_BSTATE_IN_FLIGHT buffer state.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Carlos Maiolino <cem@kernel.org>
Diffstat (limited to 'fs/xfs/xfs_buf.h')
| -rw-r--r-- | fs/xfs/xfs_buf.h | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h index 2e747555ad3f..80e06eecaf56 100644 --- a/fs/xfs/xfs_buf.h +++ b/fs/xfs/xfs_buf.h @@ -27,7 +27,6 @@ struct xfs_buf; #define XBF_READ (1u << 0) /* buffer intended for reading from device */ #define XBF_WRITE (1u << 1) /* buffer intended for writing to device */ #define XBF_READ_AHEAD (1u << 2) /* asynchronous read-ahead */ -#define XBF_NO_IOACCT (1u << 3) /* bypass I/O accounting (non-LRU bufs) */ #define XBF_ASYNC (1u << 4) /* initiator will not wait for completion */ #define XBF_DONE (1u << 5) /* all pages in the buffer uptodate */ #define XBF_STALE (1u << 6) /* buffer has been staled, do not find it */ @@ -58,7 +57,6 @@ typedef unsigned int xfs_buf_flags_t; { XBF_READ, "READ" }, \ { XBF_WRITE, "WRITE" }, \ { XBF_READ_AHEAD, "READ_AHEAD" }, \ - { XBF_NO_IOACCT, "NO_IOACCT" }, \ { XBF_ASYNC, "ASYNC" }, \ { XBF_DONE, "DONE" }, \ { XBF_STALE, "STALE" }, \ @@ -77,7 +75,6 @@ typedef unsigned int xfs_buf_flags_t; * Internal state flags. */ #define XFS_BSTATE_DISPOSE (1 << 0) /* buffer being discarded */ -#define XFS_BSTATE_IN_FLIGHT (1 << 1) /* I/O in flight */ struct xfs_buf_cache { struct rhashtable bc_hash; @@ -116,7 +113,7 @@ struct xfs_buftarg { struct shrinker *bt_shrinker; struct list_lru bt_lru; - struct percpu_counter bt_io_count; + struct percpu_counter bt_readahead_count; struct ratelimit_state bt_ioerror_rl; /* Atomic write unit values */ |