From: Alexander.Boyko Date: Wed, 28 May 2014 17:52:13 +0000 (+0400) Subject: LU-5116 ptlrpc: race at req processing X-Git-Tag: 2.5.60~45 X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=56e5a6bb4fc0329092f85016b8664da0b6ffa8a8 LU-5116 ptlrpc: race at req processing Race between ptlrpc_resend_req() and ptlrpc_check_set(). 1 thread do ptlrpc_check_set()->after_reply() 2 thread do ptlrpc_resend_req() The result is request with rq_resend = 1 and MSG_REPLY flag. When this request will came to server it will cause client eviction. The patch skip ptlrpc_resend_req logic if rq_replied is set, and clear rq_resend flag at reply_in_callback() when client got reply. Signed-off-by: Alexander Boyko Xyratex-bug-id: MRP-1888 Change-Id: If47b9a1f559ab16e4b416332ada7c73a8758d46c Reviewed-on: http://review.whamcloud.com/10471 Reviewed-by: Andreas Dilger Tested-by: Jenkins Tested-by: Maloo Reviewed-by: Mike Pershin Reviewed-by: Chris Horn Reviewed-by: Oleg Drokin --- diff --git a/lustre/ptlrpc/client.c b/lustre/ptlrpc/client.c index 3f3e220..ea8a206 100644 --- a/lustre/ptlrpc/client.c +++ b/lustre/ptlrpc/client.c @@ -2565,10 +2565,19 @@ EXPORT_SYMBOL(ptlrpc_cleanup_client); void ptlrpc_resend_req(struct ptlrpc_request *req) { DEBUG_REQ(D_HA, req, "going to resend"); + spin_lock(&req->rq_lock); + + /* Request got reply but linked to the import list still. + Let ptlrpc_check_set() to process it. */ + if (ptlrpc_client_replied(req)) { + spin_unlock(&req->rq_lock); + DEBUG_REQ(D_HA, req, "it has reply, so skip it"); + return; + } + lustre_msg_set_handle(req->rq_reqmsg, &(struct lustre_handle){ 0 }); req->rq_status = -EAGAIN; - spin_lock(&req->rq_lock); req->rq_resend = 1; req->rq_net_err = 0; req->rq_timedout = 0; diff --git a/lustre/ptlrpc/events.c b/lustre/ptlrpc/events.c index 024d22c..d7f9a11 100644 --- a/lustre/ptlrpc/events.c +++ b/lustre/ptlrpc/events.c @@ -153,6 +153,8 @@ void reply_in_callback(lnet_event_t *ev) /* Real reply */ req->rq_rep_swab_mask = 0; req->rq_replied = 1; + /* Got reply, no resend required */ + req->rq_resend = 0; req->rq_reply_off = ev->offset; req->rq_nob_received = ev->mlength; /* LNetMDUnlink can't be called under the LNET_LOCK, diff --git a/lustre/ptlrpc/niobuf.c b/lustre/ptlrpc/niobuf.c index e75599a..f779054 100644 --- a/lustre/ptlrpc/niobuf.c +++ b/lustre/ptlrpc/niobuf.c @@ -690,6 +690,8 @@ int ptl_send_rpc(struct ptlrpc_request *request, int noreply) /* If this is a re-transmit, we're required to have disengaged * cleanly from the previous attempt */ LASSERT(!request->rq_receiving_reply); + LASSERT(!((lustre_msg_get_flags(request->rq_reqmsg) & MSG_REPLAY) && + (request->rq_import->imp_state == LUSTRE_IMP_FULL))); if (unlikely(obd != NULL && obd->obd_fail)) { CDEBUG(D_HA, "muting rpc for failed imp obd %s\n",