Module Name: src
Committed By: jdolecek
Date: Sun Aug 26 21:04:16 UTC 2018
Modified Files:
src/sys/arch/xen/xen: xbd_xenbus.c
Log Message:
add event counter for the unaligned map to get a handle on how often this
actually happens
To generate a diff of this commit:
cvs rdiff -u -r1.87 -r1.88 src/sys/arch/xen/xen/xbd_xenbus.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/arch/xen/xen/xbd_xenbus.c
diff -u src/sys/arch/xen/xen/xbd_xenbus.c:1.87 src/sys/arch/xen/xen/xbd_xenbus.c:1.88
--- src/sys/arch/xen/xen/xbd_xenbus.c:1.87 Sun Aug 26 11:31:56 2018
+++ src/sys/arch/xen/xen/xbd_xenbus.c Sun Aug 26 21:04:16 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: xbd_xenbus.c,v 1.87 2018/08/26 11:31:56 bouyer Exp $ */
+/* $NetBSD: xbd_xenbus.c,v 1.88 2018/08/26 21:04:16 jdolecek Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -50,7 +50,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.87 2018/08/26 11:31:56 bouyer Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.88 2018/08/26 21:04:16 jdolecek Exp $");
#include "opt_xen.h"
@@ -151,6 +151,7 @@ struct xbd_xenbus_softc {
u_long sc_info; /* VDISK_* */
u_long sc_handle; /* from backend */
int sc_cache_flush; /* backend supports BLKIF_OP_FLUSH_DISKCACHE */
+ struct evcnt sc_cnt_map_unalign;
};
#if 0
@@ -301,6 +302,9 @@ xbd_xenbus_attach(device_t parent, devic
panic("%s: can't alloc ring", device_xname(self));
sc->sc_ring.sring = ring;
+ evcnt_attach_dynamic(&sc->sc_cnt_map_unalign, EVCNT_TYPE_MISC,
+ NULL, device_xname(self), "map unaligned");
+
/* resume shared structures and tell backend that we are ready */
if (xbd_xenbus_resume(self, PMF_Q_NONE) == false) {
uvm_km_free(kernel_map, (vaddr_t)ring, PAGE_SIZE,
@@ -384,6 +388,8 @@ xbd_xenbus_detach(device_t dev, int flag
uvm_km_free(kernel_map, (vaddr_t)sc->sc_ring.sring,
PAGE_SIZE, UVM_KMF_WIRED);
+ evcnt_detach(&sc->sc_cnt_map_unalign);
+
pmf_device_deregister(dev);
return 0;
@@ -982,6 +988,8 @@ xbd_diskstart(device_t self, struct buf
xbdreq->req_bp = bp;
xbdreq->req_data = bp->b_data;
if (__predict_false((vaddr_t)bp->b_data & (XEN_BSIZE - 1))) {
+ sc->sc_cnt_map_unalign.ev_count++;
+
if (__predict_false(xbd_map_align(xbdreq) != 0)) {
DPRINTF(("xbd_diskstart: no align\n"));
error = EAGAIN;
