From: Lai Siyao Date: Sun, 8 Mar 2015 00:24:28 +0000 (-0500) Subject: staging/lustre/llite: avoid nonatomic memory alloc under spinlock X-Git-Tag: firefly_0821_release~176^2~1998^2~138^2~354 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=aac2e54f9eb63d5cfaac1a115a939508712050da;p=firefly-linux-kernel-4.4.55.git staging/lustre/llite: avoid nonatomic memory alloc under spinlock ll_intent_drop_lock() may sleep in memory allocation, which should not be called inside spinlock. Signed-off-by: Lai Siyao Signed-off-by: Jian Yu Reviewed-on: http://review.whamcloud.com/10674 Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2272 Signed-off-by: Oleg Drokin Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/staging/lustre/lustre/llite/statahead.c b/drivers/staging/lustre/lustre/llite/statahead.c index fe732fa0d01f..b75562c6b5de 100644 --- a/drivers/staging/lustre/lustre/llite/statahead.c +++ b/drivers/staging/lustre/lustre/llite/statahead.c @@ -706,11 +706,21 @@ static int ll_statahead_interpret(struct ptlrpc_request *req, struct ll_inode_info *lli = ll_i2info(dir); struct ll_statahead_info *sai = NULL; struct ll_sa_entry *entry; + __u64 handle = 0; int wakeup; if (it_disposition(it, DISP_LOOKUP_NEG)) rc = -ENOENT; + if (rc == 0) { + /* release ibits lock ASAP to avoid deadlock when statahead + * thread enqueues lock on parent in readdir and another + * process enqueues lock on child with parent lock held, eg. + * unlink. */ + handle = it->d.lustre.it_lock_handle; + ll_intent_drop_lock(it); + } + spin_lock(&lli->lli_sa_lock); /* stale entry */ if (unlikely(lli->lli_sai == NULL || @@ -745,8 +755,7 @@ static int ll_statahead_interpret(struct ptlrpc_request *req, * when statahead thread tries to enqueue lock on parent * for readpage and other tries to enqueue lock on child * with parent's lock held, for example: unlink. */ - entry->se_handle = it->d.lustre.it_lock_handle; - ll_intent_drop_lock(it); + entry->se_handle = handle; wakeup = sa_received_empty(sai); list_add_tail(&entry->se_list, &sai->sai_entries_received);