Module Name: src
Committed By: jdolecek
Date: Wed Jun 14 20:17:46 UTC 2017
Modified Files:
src/sys/dev/ata [jdolecek-ncq]: wd.c
Log Message:
put back reset of retry count to 0 when starting processing a buf
do not use NCQ for retried transfers to speed up recovery, unless FUA
is requested
To generate a diff of this commit:
cvs rdiff -u -r1.428.2.14 -r1.428.2.15 src/sys/dev/ata/wd.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/ata/wd.c
diff -u src/sys/dev/ata/wd.c:1.428.2.14 src/sys/dev/ata/wd.c:1.428.2.15
--- src/sys/dev/ata/wd.c:1.428.2.14 Mon Apr 24 22:20:23 2017
+++ src/sys/dev/ata/wd.c Wed Jun 14 20:17:46 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: wd.c,v 1.428.2.14 2017/04/24 22:20:23 jdolecek Exp $ */
+/* $NetBSD: wd.c,v 1.428.2.15 2017/06/14 20:17:46 jdolecek Exp $ */
/*
* Copyright (c) 1998, 2001 Manuel Bouyer. All rights reserved.
@@ -54,7 +54,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: wd.c,v 1.428.2.14 2017/04/24 22:20:23 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: wd.c,v 1.428.2.15 2017/06/14 20:17:46 jdolecek Exp $");
#include "opt_ata.h"
@@ -650,6 +650,7 @@ wdstart(struct wd_softc *wd)
bp = bufq_get(wd->sc_q);
KASSERT(bp != NULL);
+ xfer->c_bio.retries = 0;
wdstart1(wd, bp, xfer);
}
@@ -685,8 +686,17 @@ wdstart1(struct wd_softc *wd, struct buf
((xfer->c_bio.bcount / wd->sc_dk.dk_label->d_secsize) > 128)))
xfer->c_bio.flags |= ATA_LBA48;
- /* If NCQ was negotiated, always use it */
- if (wd->drvp->drive_flags & ATA_DRIVE_NCQ) {
+ /*
+ * If NCQ was negotiated, always use it for the first attempt.
+ * Since device cancels all outstanding requests on error, downgrade
+ * to non-NCQ on retry, so that the retried transfer would not cause
+ * cascade failure for the other transfers if it fails again.
+ * If FUA was requested, we can't downgrade, as that would violate
+ * the semantics - FUA would not be honored. In that case, continue
+ * retrying with NCQ.
+ */
+ if (wd->drvp->drive_flags & ATA_DRIVE_NCQ &&
+ (xfer->c_bio.retries == 0 || (bp->b_flags & B_MEDIA_FUA))) {
xfer->c_bio.flags |= ATA_LBA48;
xfer->c_flags |= C_NCQ;
