2020-02-13 15:04:49

by Madhuparna Bhowmik

Subject: [PATCH] fs: nfsd: fileache.c: Use built-in RCU list checking

From: Madhuparna Bhowmik <[email protected]>

list_for_each_entry_rcu() has built-in RCU and lock checking.

Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.

Signed-off-by: Madhuparna Bhowmik <[email protected]>
---
fs/nfsd/filecache.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 32a9bf22ac08..547d2d8bde62 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -736,7 +736,7 @@ nfsd_file_find_locked(struct inode *inode, unsigned int may_flags,
unsigned char need = may_flags & NFSD_FILE_MAY_MASK;

hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head,
- nf_node) {
+ nf_node, lockdep_is_held(&nfsd_file_hashtbl[hashval].nfb_lock)) {
if ((need & nf->nf_may) != need)
continue;
if (nf->nf_inode != inode)
--
2.17.1

2020-03-03 16:55:11

by J. Bruce Fields

Subject: Re: [PATCH] fs: nfsd: fileache.c: Use built-in RCU list checking

Applying for 5.7, thanks.--b.

On Thu, Feb 13, 2020 at 08:33:59PM +0530, [email protected] wrote:
> From: Madhuparna Bhowmik <[email protected]>
>
> list_for_each_entry_rcu() has built-in RCU and lock checking.
>
> Pass cond argument to list_for_each_entry_rcu() to silence
> false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
> by default.
>
> Signed-off-by: Madhuparna Bhowmik <[email protected]>
> ---
> fs/nfsd/filecache.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
> index 32a9bf22ac08..547d2d8bde62 100644
> --- a/fs/nfsd/filecache.c
> +++ b/fs/nfsd/filecache.c
> @@ -736,7 +736,7 @@ nfsd_file_find_locked(struct inode *inode, unsigned int may_flags,
> unsigned char need = may_flags & NFSD_FILE_MAY_MASK;
>
> hlist_for_each_entry_rcu(nf, &nfsd_file_hashtbl[hashval].nfb_head,
> - nf_node) {
> + nf_node, lockdep_is_held(&nfsd_file_hashtbl[hashval].nfb_lock)) {
> if ((need & nf->nf_may) != need)
> continue;
> if (nf->nf_inode != inode)
> --
> 2.17.1