[Cluster-devel] [PATCH 3/3] Revert "GFS2: Wait for iopen glock dequeues"

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,

All three look good to me.

Acked-by: Steven Whitehouse <swhiteho@redhat.com>

Steve.


On 17/03/17 14:14, Andreas Gruenbacher wrote:
> Revert commit 86d067a797d4e8546a7c92b985f31e8cd3ec39ad: it turns out
> that waiting for iopen glock dequeues here isn't needed anymore because
> the bugs that commit was meant to fix have been fixed otherwise.
>
> In addition, we want to avoid waiting on glocks in gfs2_evict_inode in
> shrinker context because the shrinker may be invoked on behalf of DLM,
> in which case calling into DLM again would deadlock.  This commit makes
> the described scenario less likely without completely avoiding it; it's
> still a step in the right direction, though.
>
> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
> ---
>   fs/gfs2/inode.c | 3 +--
>   fs/gfs2/super.c | 8 +++-----
>   2 files changed, 4 insertions(+), 7 deletions(-)
>
> diff --git a/fs/gfs2/inode.c b/fs/gfs2/inode.c
> index e279c3c..de919f1 100644
> --- a/fs/gfs2/inode.c
> +++ b/fs/gfs2/inode.c
> @@ -202,8 +202,7 @@ struct inode *gfs2_inode_lookup(struct super_block *sb, unsigned int type,
>   fail_refresh:
>   	ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
>   	ip->i_iopen_gh.gh_gl->gl_object = NULL;
> -	gfs2_glock_dq_wait(&ip->i_iopen_gh);
> -	gfs2_holder_uninit(&ip->i_iopen_gh);
> +	gfs2_glock_dq_uninit(&ip->i_iopen_gh);
>   fail_put:
>   	if (io_gl)
>   		gfs2_glock_put(io_gl);
> diff --git a/fs/gfs2/super.c b/fs/gfs2/super.c
> index 2a9a830..29b0473 100644
> --- a/fs/gfs2/super.c
> +++ b/fs/gfs2/super.c
> @@ -1539,8 +1539,7 @@ static void gfs2_evict_inode(struct inode *inode)
>   	error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
>   	if (unlikely(error)) {
>   		ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
> -		gfs2_glock_dq_wait(&ip->i_iopen_gh);
> -		gfs2_holder_uninit(&ip->i_iopen_gh);
> +		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
>   		goto out;
>   	}
>   
> @@ -1618,7 +1617,7 @@ static void gfs2_evict_inode(struct inode *inode)
>   	if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
>   		if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
>   			ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
> -			gfs2_glock_dq_wait(&ip->i_iopen_gh);
> +			gfs2_glock_dq(&ip->i_iopen_gh);
>   		}
>   		gfs2_holder_uninit(&ip->i_iopen_gh);
>   	}
> @@ -1640,8 +1639,7 @@ static void gfs2_evict_inode(struct inode *inode)
>   	if (gfs2_holder_initialized(&ip->i_iopen_gh)) {
>   		ip->i_iopen_gh.gh_gl->gl_object = NULL;
>   		ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
> -		gfs2_glock_dq_wait(&ip->i_iopen_gh);
> -		gfs2_holder_uninit(&ip->i_iopen_gh);
> +		gfs2_glock_dq_uninit(&ip->i_iopen_gh);
>   	}
>   }
>