[PATCH] erofs: free pcluster right after decompression if cache decompression is disabled

[Chunhai Guo]

When the erofs cache decompression is disabled
(EROFS_ZIP_CACHE_DISABLED), all pages in pcluster are freed right after
decompression. There is no need to cache the pcluster as well and it can
be freed.

Signed-off-by: Chunhai Guo <guochunhai at vivo.com>
---
 fs/erofs/internal.h |  3 ++-
 fs/erofs/zdata.c    |  4 ++--
 fs/erofs/zutil.c    | 32 +++++++++++++++++++-------------
 3 files changed, 23 insertions(+), 16 deletions(-)

diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index e768990bf20f..cc6a61a422d8 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -449,7 +449,8 @@ static inline void erofs_pagepool_add(struct page **pagepool, struct page *page)
 void erofs_release_pages(struct page **pagepool);
 
 #ifdef CONFIG_EROFS_FS_ZIP
-void erofs_workgroup_put(struct erofs_workgroup *grp);
+void erofs_workgroup_put(struct erofs_sb_info *sbi,
+		struct erofs_workgroup *grp);
 struct erofs_workgroup *erofs_find_workgroup(struct super_block *sb,
 					     pgoff_t index);
 struct erofs_workgroup *erofs_insert_workgroup(struct super_block *sb,
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index 428ab617e0e4..03b939dc2943 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -924,7 +924,7 @@ static void z_erofs_pcluster_end(struct z_erofs_decompress_frontend *fe)
 	 * any longer if the pcluster isn't hosted by ourselves.
 	 */
 	if (fe->mode < Z_EROFS_PCLUSTER_FOLLOWED_NOINPLACE)
-		erofs_workgroup_put(&pcl->obj);
+		erofs_workgroup_put(EROFS_I_SB(fe->inode), &pcl->obj);
 
 	fe->pcl = NULL;
 }
@@ -1355,7 +1355,7 @@ static void z_erofs_decompress_queue(const struct z_erofs_decompressqueue *io,
 		if (z_erofs_is_inline_pcluster(be.pcl))
 			z_erofs_free_pcluster(be.pcl);
 		else
-			erofs_workgroup_put(&be.pcl->obj);
+			erofs_workgroup_put(EROFS_SB(io->sb), &be.pcl->obj);
 	}
 }
 
diff --git a/fs/erofs/zutil.c b/fs/erofs/zutil.c
index 9b53883e5caf..4f5783cca5c6 100644
--- a/fs/erofs/zutil.c
+++ b/fs/erofs/zutil.c
@@ -284,18 +284,6 @@ static void  __erofs_workgroup_free(struct erofs_workgroup *grp)
 	erofs_workgroup_free_rcu(grp);
 }
 
-void erofs_workgroup_put(struct erofs_workgroup *grp)
-{
-	if (lockref_put_or_lock(&grp->lockref))
-		return;
-
-	DBG_BUGON(__lockref_is_dead(&grp->lockref));
-	if (grp->lockref.count == 1)
-		atomic_long_inc(&erofs_global_shrink_cnt);
-	--grp->lockref.count;
-	spin_unlock(&grp->lockref.lock);
-}
-
 static bool erofs_try_to_release_workgroup(struct erofs_sb_info *sbi,
 					   struct erofs_workgroup *grp)
 {
@@ -310,7 +298,8 @@ static bool erofs_try_to_release_workgroup(struct erofs_sb_info *sbi,
 	 * the XArray. Otherwise some cached pages could be still attached to
 	 * the orphan old workgroup when the new one is available in the tree.
 	 */
-	if (erofs_try_to_free_all_cached_folios(sbi, grp))
+	if (!erofs_is_cache_disabled(sbi)
+			&& erofs_try_to_free_all_cached_folios(sbi, grp))
 		goto out;
 
 	/*
@@ -329,6 +318,23 @@ static bool erofs_try_to_release_workgroup(struct erofs_sb_info *sbi,
 	return free;
 }
 
+void erofs_workgroup_put(struct erofs_sb_info *sbi, struct erofs_workgroup *grp)
+{
+	if (lockref_put_or_lock(&grp->lockref))
+		return;
+
+	DBG_BUGON(__lockref_is_dead(&grp->lockref));
+	if (--grp->lockref.count == 0)
+		atomic_long_inc(&erofs_global_shrink_cnt);
+	spin_unlock(&grp->lockref.lock);
+
+	if (erofs_is_cache_disabled(sbi)) {
+		xa_lock(&sbi->managed_pslots);
+		erofs_try_to_release_workgroup(sbi, grp);
+		xa_unlock(&sbi->managed_pslots);
+	}
+}
+
 static unsigned long erofs_shrink_workstation(struct erofs_sb_info *sbi,
 					      unsigned long nr_shrink)
 {
-- 
2.25.1