From 047d4abc4df740d48e0386ecc7d52f6d312187af Mon Sep 17 00:00:00 2001 From: Gao Xiang Date: Sat, 16 Feb 2019 16:46:50 +0800 Subject: [PATCH] staging: erofs: remove rcu_read_lock() in erofs_try_to_free_cached_page page_private(page) cannot be changed if page lock is taken. Besides, the corresponding workgroup won't be freed if the page is already protected by page lock, therefore no need to take rcu read lock. Signed-off-by: Gao Xiang Reviewed-by: Chao Yu Signed-off-by: Greg Kroah-Hartman --- drivers/staging/erofs/unzip_vle.c | 16 +++++----------- 1 file changed, 5 insertions(+), 11 deletions(-) diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c index 2b5951f233db..a127d8db76d8 100644 --- a/drivers/staging/erofs/unzip_vle.c +++ b/drivers/staging/erofs/unzip_vle.c @@ -238,14 +238,9 @@ int erofs_try_to_free_cached_page(struct address_space *mapping, { struct erofs_sb_info *const sbi = EROFS_SB(mapping->host->i_sb); const unsigned int clusterpages = erofs_clusterpages(sbi); - - struct z_erofs_vle_workgroup *grp; + struct z_erofs_vle_workgroup *const grp = (void *)page_private(page); int ret = 0; /* 0 - busy */ - /* prevent the workgroup from being freed */ - rcu_read_lock(); - grp = (void *)page_private(page); - if (erofs_workgroup_try_to_freeze(&grp->obj, 1)) { unsigned int i; @@ -257,12 +252,11 @@ int erofs_try_to_free_cached_page(struct address_space *mapping, } } erofs_workgroup_unfreeze(&grp->obj, 1); - } - rcu_read_unlock(); - if (ret) { - ClearPagePrivate(page); - put_page(page); + if (ret) { + ClearPagePrivate(page); + put_page(page); + } } return ret; }