From: Harshad Shirwadkar harshadshirwadkar@gmail.com
[ Upstream commit 0915e464cb274648e1ef1663e1356e53ff400983 ]
Move fast commit stats updating logic to a separate function from ext4_fc_commit(). This significantly improves readability of ext4_fc_commit().
Signed-off-by: Harshad Shirwadkar harshadshirwadkar@gmail.com Link: https://lore.kernel.org/r/20211223202140.2061101-4-harshads@google.com Signed-off-by: Theodore Ts'o tytso@mit.edu Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ext4/ext4.h | 1 - fs/ext4/fast_commit.c | 99 +++++++++++++++++++++++-------------------- fs/ext4/fast_commit.h | 27 ++++++------ 3 files changed, 68 insertions(+), 59 deletions(-)
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index f80e4de726869..470fd3c2aef54 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1747,7 +1747,6 @@ struct ext4_sb_info { spinlock_t s_fc_lock; struct buffer_head *s_fc_bh; struct ext4_fc_stats s_fc_stats; - u64 s_fc_avg_commit_time; #ifdef CONFIG_EXT4_DEBUG int s_fc_debug_max_replay; #endif diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c index 48e522bb7bca4..1b935feec6f6b 100644 --- a/fs/ext4/fast_commit.c +++ b/fs/ext4/fast_commit.c @@ -1075,6 +1075,32 @@ static int ext4_fc_perform_commit(journal_t *journal) return ret; }
+static void ext4_fc_update_stats(struct super_block *sb, int status, + u64 commit_time, int nblks) +{ + struct ext4_fc_stats *stats = &EXT4_SB(sb)->s_fc_stats; + + jbd_debug(1, "Fast commit ended with status = %d", status); + if (status == EXT4_FC_STATUS_OK) { + stats->fc_num_commits++; + stats->fc_numblks += nblks; + if (likely(stats->s_fc_avg_commit_time)) + stats->s_fc_avg_commit_time = + (commit_time + + stats->s_fc_avg_commit_time * 3) / 4; + else + stats->s_fc_avg_commit_time = commit_time; + } else if (status == EXT4_FC_STATUS_FAILED || + status == EXT4_FC_STATUS_INELIGIBLE) { + if (status == EXT4_FC_STATUS_FAILED) + stats->fc_failed_commits++; + stats->fc_ineligible_commits++; + } else { + stats->fc_skipped_commits++; + } + trace_ext4_fc_commit_stop(sb, nblks, status); +} + /* * The main commit entry point. Performs a fast commit for transaction * commit_tid if needed. If it's not possible to perform a fast commit @@ -1087,7 +1113,7 @@ int ext4_fc_commit(journal_t *journal, tid_t commit_tid) struct ext4_sb_info *sbi = EXT4_SB(sb); int nblks = 0, ret, bsize = journal->j_blocksize; int subtid = atomic_read(&sbi->s_fc_subtid); - int reason = EXT4_FC_REASON_OK, fc_bufs_before = 0; + int status = EXT4_FC_STATUS_OK, fc_bufs_before = 0; ktime_t start_time, commit_time;
trace_ext4_fc_commit_start(sb); @@ -1104,69 +1130,52 @@ int ext4_fc_commit(journal_t *journal, tid_t commit_tid) if (atomic_read(&sbi->s_fc_subtid) <= subtid && commit_tid > journal->j_commit_sequence) goto restart_fc; - reason = EXT4_FC_REASON_ALREADY_COMMITTED; - goto out; + ext4_fc_update_stats(sb, EXT4_FC_STATUS_SKIPPED, 0, 0); + return 0; } else if (ret) { - sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++; - reason = EXT4_FC_REASON_FC_START_FAILED; - goto out; + /* + * Commit couldn't start. Just update stats and perform a + * full commit. + */ + ext4_fc_update_stats(sb, EXT4_FC_STATUS_FAILED, 0, 0); + return jbd2_complete_transaction(journal, commit_tid); } + /* * After establishing journal barrier via jbd2_fc_begin_commit(), check * if we are fast commit ineligible. */ if (ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE)) { - reason = EXT4_FC_REASON_INELIGIBLE; - goto out; + status = EXT4_FC_STATUS_INELIGIBLE; + goto fallback; }
fc_bufs_before = (sbi->s_fc_bytes + bsize - 1) / bsize; ret = ext4_fc_perform_commit(journal); if (ret < 0) { - sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++; - reason = EXT4_FC_REASON_FC_FAILED; - goto out; + status = EXT4_FC_STATUS_FAILED; + goto fallback; } nblks = (sbi->s_fc_bytes + bsize - 1) / bsize - fc_bufs_before; ret = jbd2_fc_wait_bufs(journal, nblks); if (ret < 0) { - sbi->s_fc_stats.fc_ineligible_reason_count[EXT4_FC_COMMIT_FAILED]++; - reason = EXT4_FC_REASON_FC_FAILED; - goto out; + status = EXT4_FC_STATUS_FAILED; + goto fallback; } atomic_inc(&sbi->s_fc_subtid); - jbd2_fc_end_commit(journal); -out: - spin_lock(&sbi->s_fc_lock); - if (reason != EXT4_FC_REASON_OK && - reason != EXT4_FC_REASON_ALREADY_COMMITTED) { - sbi->s_fc_stats.fc_ineligible_commits++; - } else { - sbi->s_fc_stats.fc_num_commits++; - sbi->s_fc_stats.fc_numblks += nblks; - } - spin_unlock(&sbi->s_fc_lock); - nblks = (reason == EXT4_FC_REASON_OK) ? nblks : 0; - trace_ext4_fc_commit_stop(sb, nblks, reason); - commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); + ret = jbd2_fc_end_commit(journal); /* - * weight the commit time higher than the average time so we don't - * react too strongly to vast changes in the commit time + * weight the commit time higher than the average time so we + * don't react too strongly to vast changes in the commit time */ - if (likely(sbi->s_fc_avg_commit_time)) - sbi->s_fc_avg_commit_time = (commit_time + - sbi->s_fc_avg_commit_time * 3) / 4; - else - sbi->s_fc_avg_commit_time = commit_time; - jbd_debug(1, - "Fast commit ended with blks = %d, reason = %d, subtid - %d", - nblks, reason, subtid); - if (reason == EXT4_FC_REASON_FC_FAILED) - return jbd2_fc_end_commit_fallback(journal); - if (reason == EXT4_FC_REASON_FC_START_FAILED || - reason == EXT4_FC_REASON_INELIGIBLE) - return jbd2_complete_transaction(journal, commit_tid); - return 0; + commit_time = ktime_to_ns(ktime_sub(ktime_get(), start_time)); + ext4_fc_update_stats(sb, status, commit_time, nblks); + return ret; + +fallback: + ret = jbd2_fc_end_commit_fallback(journal); + ext4_fc_update_stats(sb, status, 0, 0); + return ret; }
/* @@ -2132,7 +2141,7 @@ int ext4_fc_info_show(struct seq_file *seq, void *v) "fc stats:\n%ld commits\n%ld ineligible\n%ld numblks\n%lluus avg_commit_time\n", stats->fc_num_commits, stats->fc_ineligible_commits, stats->fc_numblks, - div_u64(sbi->s_fc_avg_commit_time, 1000)); + div_u64(stats->s_fc_avg_commit_time, 1000)); seq_puts(seq, "Ineligible reasons:\n"); for (i = 0; i < EXT4_FC_REASON_MAX; i++) seq_printf(seq, ""%s":\t%d\n", fc_ineligible_reasons[i], diff --git a/fs/ext4/fast_commit.h b/fs/ext4/fast_commit.h index 937c381b4c85e..083ad1cb705a7 100644 --- a/fs/ext4/fast_commit.h +++ b/fs/ext4/fast_commit.h @@ -71,21 +71,19 @@ struct ext4_fc_tail { };
/* - * Fast commit reason codes + * Fast commit status codes + */ +enum { + EXT4_FC_STATUS_OK = 0, + EXT4_FC_STATUS_INELIGIBLE, + EXT4_FC_STATUS_SKIPPED, + EXT4_FC_STATUS_FAILED, +}; + +/* + * Fast commit ineligiblity reasons: */ enum { - /* - * Commit status codes: - */ - EXT4_FC_REASON_OK = 0, - EXT4_FC_REASON_INELIGIBLE, - EXT4_FC_REASON_ALREADY_COMMITTED, - EXT4_FC_REASON_FC_START_FAILED, - EXT4_FC_REASON_FC_FAILED, - - /* - * Fast commit ineligiblity reasons: - */ EXT4_FC_REASON_XATTR = 0, EXT4_FC_REASON_CROSS_RENAME, EXT4_FC_REASON_JOURNAL_FLAG_CHANGE, @@ -117,7 +115,10 @@ struct ext4_fc_stats { unsigned int fc_ineligible_reason_count[EXT4_FC_REASON_MAX]; unsigned long fc_num_commits; unsigned long fc_ineligible_commits; + unsigned long fc_failed_commits; + unsigned long fc_skipped_commits; unsigned long fc_numblks; + u64 s_fc_avg_commit_time; };
#define EXT4_FC_REPLAY_REALLOC_INCREMENT 4