svn commit: r322976 - head/sys/cam/scsi

[Warner Losh]

Author: imp
Date: Mon Aug 28 19:25:49 2017
New Revision: 322976
URL: https://svnweb.freebsd.org/changeset/base/322976

Log:
  Add comment about where we need to place this routine, and why.
  
  Sponsored by: Netflix

Modified:
  head/sys/cam/scsi/scsi_da.c

Modified: head/sys/cam/scsi/scsi_da.c
==============================================================================
--- head/sys/cam/scsi/scsi_da.c	Mon Aug 28 19:17:28 2017	(r322975)
+++ head/sys/cam/scsi/scsi_da.c	Mon Aug 28 19:25:49 2017	(r322976)
@@ -4200,6 +4200,12 @@ dadone(struct cam_periph *periph, union ccb *done_ccb)
 		if (LIST_EMPTY(&softc->pending_ccbs))
 			softc->flags |= DA_FLAG_WAS_OTAG;
 
+		/*
+		 * We need to call cam_iosched before we call biodone so that we
+		 * don't measure any activity that happens in the completion
+		 * routine, which in the case of sendfile can be quite
+		 * extensive.
+		 */
 		cam_iosched_bio_complete(softc->cam_iosched, bp, done_ccb);
 		xpt_release_ccb(done_ccb);
 		if (state == DA_CCB_DELETE) {