From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
When we're scanning the directory tree, we bump nr_dirs every time we
think we're going to queue a new directory to process, and we decrement
it every time we're finished doing something with a directory
(successful or not). We forgot to undo a counter increment when
workqueue_add fails, so refactor the code into helpers and call them
as necessary for correct operation.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
scrub/vfs.c | 38 +++++++++++++++++++++++++++++---------
1 file changed, 29 insertions(+), 9 deletions(-)
diff --git a/scrub/vfs.c b/scrub/vfs.c
index ea2866d9..b358ab4a 100644
--- a/scrub/vfs.c
+++ b/scrub/vfs.c
@@ -45,6 +45,32 @@ struct scan_fs_tree_dir {
static void scan_fs_dir(struct workqueue *wq, xfs_agnumber_t agno, void *arg);
+/* Increment the number of directories that are queued for processing. */
+static void
+inc_nr_dirs(
+ struct scan_fs_tree *sft)
+{
+ pthread_mutex_lock(&sft->lock);
+ sft->nr_dirs++;
+ pthread_mutex_unlock(&sft->lock);
+}
+
+/*
+ * Decrement the number of directories that are queued for processing and if
+ * we ran out of dirs to process, wake up anyone who was waiting for processing
+ * to finish.
+ */
+static void
+dec_nr_dirs(
+ struct scan_fs_tree *sft)
+{
+ pthread_mutex_lock(&sft->lock);
+ sft->nr_dirs--;
+ if (sft->nr_dirs == 0)
+ pthread_cond_signal(&sft->wakeup);
+ pthread_mutex_unlock(&sft->lock);
+}
+
/* Queue a directory for scanning. */
static bool
queue_subdir(
@@ -73,11 +99,10 @@ queue_subdir(
new_sftd->sft = sft;
new_sftd->rootdir = is_rootdir;
- pthread_mutex_lock(&sft->lock);
- sft->nr_dirs++;
- pthread_mutex_unlock(&sft->lock);
+ inc_nr_dirs(sft);
error = workqueue_add(wq, scan_fs_dir, 0, new_sftd);
if (error) {
+ dec_nr_dirs(sft);
str_info(ctx, ctx->mntpoint,
_("Could not queue subdirectory scan work."));
return false;
@@ -172,12 +197,7 @@ scan_fs_dir(
str_errno(ctx, sftd->path);
out:
- pthread_mutex_lock(&sft->lock);
- sft->nr_dirs--;
- if (sft->nr_dirs == 0)
- pthread_cond_signal(&sft->wakeup);
- pthread_mutex_unlock(&sft->lock);
-
+ dec_nr_dirs(sft);
free(sftd->path);
free(sftd);
}
