[14/18] ext4: use a per-superblock fsverity workqueue

Commit Message

Darrick J. Wong April 30, 2024, 3:23 a.m. UTC

From: Darrick J. Wong <[e-mail]>

Switch ext4 to use a per-sb fsverity workqueue instead of a systemwide
workqueue.

Signed-off-by: Darrick J. Wong <[e-mail]>
---
 fs/ext4/super.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

Patch

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 044135796f2b6..d54c74c222999 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -5332,6 +5332,17 @@  static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
 #endif
 #ifdef CONFIG_FS_VERITY
 	sb->s_vop = &ext4_verityops;
+	/*
+	 * Use a high-priority workqueue to prioritize verification work, which
+	 * blocks reads from completing, over regular application tasks.
+	 *
+	 * For performance reasons, don't use an unbound workqueue.  Using an
+	 * unbound workqueue for crypto operations causes excessive scheduler
+	 * latency on ARM64.
+	 */
+	err = fsverity_init_wq(sb, WQ_HIGHPRI, num_online_cpus());
+	if (err)
+		goto failed_mount3a;
 #endif
 #ifdef CONFIG_QUOTA
 	sb->dq_op = &ext4_quota_operations;