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| author | Harshad Shirwadkar <harshadshirwadkar@gmail.com> | 2025-05-08 20:59:06 +0300 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2025-05-09 04:56:17 +0300 |
| commit | 86e07d4b9b0497afef78af773c74258c8f63030f (patch) | |
| tree | 726d0660d4607067a01fe70f1c0c459a4eaa9370 /fs/ext4/fast_commit.c | |
| parent | 69f35ca189300ddba29a16214159beef45bbd984 (diff) | |
| download | linux-86e07d4b9b0497afef78af773c74258c8f63030f.tar.xz | |
ext4: temporarily elevate commit thread priority
Unlike JBD2 based full commits, there is no dedicated journal thread
for fast commits. Thus to reduce scheduling delays between IO
submission and completion, temporarily elevate the committer thread's
priority to match the configured priority of the JBD2 journal
thread.
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20250508175908.1004880-8-harshadshirwadkar@gmail.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/fast_commit.c')
| -rw-r--r-- | fs/ext4/fast_commit.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index 06dda39326b4..5f6a8ec249b9 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -1216,6 +1216,7 @@ int ext4_fc_commit(journal_t *journal, tid_t commit_tid) int subtid = atomic_read(&sbi->s_fc_subtid); int status = EXT4_FC_STATUS_OK, fc_bufs_before = 0; ktime_t start_time, commit_time; + int old_ioprio, journal_ioprio; if (!test_opt2(sb, JOURNAL_FAST_COMMIT)) return jbd2_complete_transaction(journal, commit_tid); @@ -1223,6 +1224,7 @@ int ext4_fc_commit(journal_t *journal, tid_t commit_tid) trace_ext4_fc_commit_start(sb, commit_tid); start_time = ktime_get(); + old_ioprio = get_current_ioprio(); restart_fc: ret = jbd2_fc_begin_commit(journal, commit_tid); @@ -1253,6 +1255,15 @@ restart_fc: goto fallback; } + /* + * Now that we know that this thread is going to do a fast commit, + * elevate the priority to match that of the journal thread. + */ + if (journal->j_task->io_context) + journal_ioprio = sbi->s_journal->j_task->io_context->ioprio; + else + journal_ioprio = EXT4_DEF_JOURNAL_IOPRIO; + set_task_ioprio(current, journal_ioprio); fc_bufs_before = (sbi->s_fc_bytes + bsize - 1) / bsize; ret = ext4_fc_perform_commit(journal); if (ret < 0) { @@ -1267,6 +1278,7 @@ restart_fc: } atomic_inc(&sbi->s_fc_subtid); ret = jbd2_fc_end_commit(journal); + set_task_ioprio(current, old_ioprio); /* * weight the commit time higher than the average time so we * don't react too strongly to vast changes in the commit time @@ -1276,6 +1288,7 @@ restart_fc: return ret; fallback: + set_task_ioprio(current, old_ioprio); ret = jbd2_fc_end_commit_fallback(journal); ext4_fc_update_stats(sb, status, 0, 0, commit_tid); return ret; |