Message ID | 20190322154425.3852517-21-arnd@arndb.de (mailing list archive) |
---|---|
State | New, archived |
Headers | show |
Series | candidates from spreadtrum 4.4 product kernel | expand |
On Fri, Mar 22, 2019 at 04:44:11PM +0100, Arnd Bergmann wrote: > From: Al Viro <viro@ZenIV.linux.org.uk> > > It's not hard to trigger a bunch of d_invalidate() on the same > dentry in parallel. They end up fighting each other - any > dentry picked for removal by one will be skipped by the rest > and we'll go for the next iteration through the entire > subtree, even if everything is being skipped. Morevoer, we > immediately go back to scanning the subtree. The only thing > we really need is to dissolve all mounts in the subtree and > as soon as we've nothing left to do, we can just unhash the > dentry and bugger off. > > Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> > (cherry picked from commit 81be24d263dbeddaba35827036d6f6787a59c2c3) > Signed-off-by: Arnd Bergmann <arnd@arndb.de> > --- > fs/dcache.c | 10 ++++------ > 1 file changed, 4 insertions(+), 6 deletions(-) Also added to 4.9.y
diff --git a/fs/dcache.c b/fs/dcache.c index 9ffe60702299..cb554e406545 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -1510,7 +1510,7 @@ static void check_and_drop(void *_data) { struct detach_data *data = _data; - if (!data->mountpoint && !data->select.found) + if (!data->mountpoint && list_empty(&data->select.dispose)) __d_drop(data->select.start); } @@ -1552,17 +1552,15 @@ void d_invalidate(struct dentry *dentry) d_walk(dentry, &data, detach_and_collect, check_and_drop); - if (data.select.found) + if (!list_empty(&data.select.dispose)) shrink_dentry_list(&data.select.dispose); + else if (!data.mountpoint) + return; if (data.mountpoint) { detach_mounts(data.mountpoint); dput(data.mountpoint); } - - if (!data.mountpoint && !data.select.found) - break; - cond_resched(); } }