svn commit: r261515 - head/sys/dev/isp

[Alexander Motin]

Author: mav
Date: Wed Feb  5 16:22:02 2014
New Revision: 261515
URL: http://svnweb.freebsd.org/changeset/base/261515

Log:
  Fix I/O freezes in some cases, caused by r257916.
  
  Delaying isp_reqodx update, we should be ready to update it every time
  we read it.  Otherwise requests using several indexes may be requeued
  ndefinitely without ever updating the variable.
  
  MFC after:	3 days

Modified:
  head/sys/dev/isp/isp_library.c

Modified: head/sys/dev/isp/isp_library.c
==============================================================================
--- head/sys/dev/isp/isp_library.c	Wed Feb  5 14:44:59 2014	(r261514)
+++ head/sys/dev/isp/isp_library.c	Wed Feb  5 16:22:02 2014	(r261515)
@@ -144,7 +144,9 @@ isp_send_cmd(ispsoftc_t *isp, void *fqe,
 	while (seg < nsegs) {
 		nxtnxt = ISP_NXT_QENTRY(nxt, RQUEST_QUEUE_LEN(isp));
 		if (nxtnxt == isp->isp_reqodx) {
-			return (CMD_EAGAIN);
+			isp->isp_reqodx = ISP_READ(isp, isp->isp_rqstoutrp);
+			if (nxtnxt == isp->isp_reqodx)
+				return (CMD_EAGAIN);
 		}
 		ISP_MEMZERO(storage, QENTRY_LEN);
 		qe1 = ISP_QUEUE_ENTRY(isp->isp_rquest, nxt);
@@ -2210,7 +2212,9 @@ isp_send_tgt_cmd(ispsoftc_t *isp, void *
 	while (seg < nsegs) {
 		nxtnxt = ISP_NXT_QENTRY(nxt, RQUEST_QUEUE_LEN(isp));
 		if (nxtnxt == isp->isp_reqodx) {
-			return (CMD_EAGAIN);
+			isp->isp_reqodx = ISP_READ(isp, isp->isp_rqstoutrp);
+			if (nxtnxt == isp->isp_reqodx)
+				return (CMD_EAGAIN);
 		}
 		ISP_MEMZERO(storage, QENTRY_LEN);
 		qe1 = ISP_QUEUE_ENTRY(isp->isp_rquest, nxt);