| Message ID | 1546839359-5478-1-git-send-email-dongli.zhang@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v4,1/2] xen/blkback: add stack variable 'blkif' in connect_ring() | expand |
> -----Original Message----- > From: Dongli Zhang [mailto:dongli.zhang@oracle.com] > Sent: 07 January 2019 05:36 > To: xen-devel@lists.xenproject.org; linux-block@vger.kernel.org; linux- > kernel@vger.kernel.org > Cc: konrad.wilk@oracle.com; Roger Pau Monne <roger.pau@citrix.com>; > axboe@kernel.dk; Paul Durrant <Paul.Durrant@citrix.com> > Subject: [PATCH v4 1/2] xen/blkback: add stack variable 'blkif' in > connect_ring() > > As 'be->blkif' is used for many times in connect_ring(), the stack > variable > 'blkif' is added to substitute 'be-blkif'. > > Suggested-by: Paul Durrant <paul.durrant@citrix.com> > Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> That looks better :-) Reviewed-by: Paul Durrant <paul.durrant@citrix.com> > --- > drivers/block/xen-blkback/xenbus.c | 27 ++++++++++++++------------- > 1 file changed, 14 insertions(+), 13 deletions(-) > > diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen- > blkback/xenbus.c > index a4bc74e..a4aadac 100644 > --- a/drivers/block/xen-blkback/xenbus.c > +++ b/drivers/block/xen-blkback/xenbus.c > @@ -1023,6 +1023,7 @@ static int read_per_ring_refs(struct xen_blkif_ring > *ring, const char *dir) > static int connect_ring(struct backend_info *be) > { > struct xenbus_device *dev = be->dev; > + struct xen_blkif *blkif = be->blkif; > unsigned int pers_grants; > char protocol[64] = ""; > int err, i; > @@ -1033,25 +1034,25 @@ static int connect_ring(struct backend_info *be) > > pr_debug("%s %s\n", __func__, dev->otherend); > > - be->blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; > + blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; > err = xenbus_scanf(XBT_NIL, dev->otherend, "protocol", > "%63s", protocol); > if (err <= 0) > strcpy(protocol, "unspecified, assuming default"); > else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_NATIVE)) > - be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; > + blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; > else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_32)) > - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; > + blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; > else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_64)) > - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; > + blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; > else { > xenbus_dev_fatal(dev, err, "unknown fe protocol %s", > protocol); > return -ENOSYS; > } > pers_grants = xenbus_read_unsigned(dev->otherend, "feature- > persistent", > 0); > - be->blkif->vbd.feature_gnt_persistent = pers_grants; > - be->blkif->vbd.overflow_max_grants = 0; > + blkif->vbd.feature_gnt_persistent = pers_grants; > + blkif->vbd.overflow_max_grants = 0; > > /* > * Read the number of hardware queues from frontend. > @@ -1067,16 +1068,16 @@ static int connect_ring(struct backend_info *be) > requested_num_queues, xenblk_max_queues); > return -ENOSYS; > } > - be->blkif->nr_rings = requested_num_queues; > - if (xen_blkif_alloc_rings(be->blkif)) > + blkif->nr_rings = requested_num_queues; > + if (xen_blkif_alloc_rings(blkif)) > return -ENOMEM; > > pr_info("%s: using %d queues, protocol %d (%s) %s\n", dev->nodename, > - be->blkif->nr_rings, be->blkif->blk_protocol, protocol, > + blkif->nr_rings, blkif->blk_protocol, protocol, > pers_grants ? "persistent grants" : ""); > > - if (be->blkif->nr_rings == 1) > - return read_per_ring_refs(&be->blkif->rings[0], dev- > >otherend); > + if (blkif->nr_rings == 1) > + return read_per_ring_refs(&blkif->rings[0], dev->otherend); > else { > xspathsize = strlen(dev->otherend) + xenstore_path_ext_size; > xspath = kmalloc(xspathsize, GFP_KERNEL); > @@ -1085,10 +1086,10 @@ static int connect_ring(struct backend_info *be) > return -ENOMEM; > } > > - for (i = 0; i < be->blkif->nr_rings; i++) { > + for (i = 0; i < blkif->nr_rings; i++) { > memset(xspath, 0, xspathsize); > snprintf(xspath, xspathsize, "%s/queue-%u", dev- > >otherend, i); > - err = read_per_ring_refs(&be->blkif->rings[i], xspath); > + err = read_per_ring_refs(&blkif->rings[i], xspath); > if (err) { > kfree(xspath); > return err; > -- > 2.7.4
On Mon, Jan 07, 2019 at 01:35:58PM +0800, Dongli Zhang wrote: > As 'be->blkif' is used for many times in connect_ring(), the stack variable > 'blkif' is added to substitute 'be-blkif'. > > Suggested-by: Paul Durrant <paul.durrant@citrix.com> > Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c index a4bc74e..a4aadac 100644 --- a/drivers/block/xen-blkback/xenbus.c +++ b/drivers/block/xen-blkback/xenbus.c @@ -1023,6 +1023,7 @@ static int read_per_ring_refs(struct xen_blkif_ring *ring, const char *dir) static int connect_ring(struct backend_info *be) { struct xenbus_device *dev = be->dev; + struct xen_blkif *blkif = be->blkif; unsigned int pers_grants; char protocol[64] = ""; int err, i; @@ -1033,25 +1034,25 @@ static int connect_ring(struct backend_info *be) pr_debug("%s %s\n", __func__, dev->otherend); - be->blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; + blkif->blk_protocol = BLKIF_PROTOCOL_DEFAULT; err = xenbus_scanf(XBT_NIL, dev->otherend, "protocol", "%63s", protocol); if (err <= 0) strcpy(protocol, "unspecified, assuming default"); else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_NATIVE)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; + blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE; else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_32)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; + blkif->blk_protocol = BLKIF_PROTOCOL_X86_32; else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_64)) - be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; + blkif->blk_protocol = BLKIF_PROTOCOL_X86_64; else { xenbus_dev_fatal(dev, err, "unknown fe protocol %s", protocol); return -ENOSYS; } pers_grants = xenbus_read_unsigned(dev->otherend, "feature-persistent", 0); - be->blkif->vbd.feature_gnt_persistent = pers_grants; - be->blkif->vbd.overflow_max_grants = 0; + blkif->vbd.feature_gnt_persistent = pers_grants; + blkif->vbd.overflow_max_grants = 0; /* * Read the number of hardware queues from frontend. @@ -1067,16 +1068,16 @@ static int connect_ring(struct backend_info *be) requested_num_queues, xenblk_max_queues); return -ENOSYS; } - be->blkif->nr_rings = requested_num_queues; - if (xen_blkif_alloc_rings(be->blkif)) + blkif->nr_rings = requested_num_queues; + if (xen_blkif_alloc_rings(blkif)) return -ENOMEM; pr_info("%s: using %d queues, protocol %d (%s) %s\n", dev->nodename, - be->blkif->nr_rings, be->blkif->blk_protocol, protocol, + blkif->nr_rings, blkif->blk_protocol, protocol, pers_grants ? "persistent grants" : ""); - if (be->blkif->nr_rings == 1) - return read_per_ring_refs(&be->blkif->rings[0], dev->otherend); + if (blkif->nr_rings == 1) + return read_per_ring_refs(&blkif->rings[0], dev->otherend); else { xspathsize = strlen(dev->otherend) + xenstore_path_ext_size; xspath = kmalloc(xspathsize, GFP_KERNEL); @@ -1085,10 +1086,10 @@ static int connect_ring(struct backend_info *be) return -ENOMEM; } - for (i = 0; i < be->blkif->nr_rings; i++) { + for (i = 0; i < blkif->nr_rings; i++) { memset(xspath, 0, xspathsize); snprintf(xspath, xspathsize, "%s/queue-%u", dev->otherend, i); - err = read_per_ring_refs(&be->blkif->rings[i], xspath); + err = read_per_ring_refs(&blkif->rings[i], xspath); if (err) { kfree(xspath); return err;
As 'be->blkif' is used for many times in connect_ring(), the stack variable 'blkif' is added to substitute 'be-blkif'. Suggested-by: Paul Durrant <paul.durrant@citrix.com> Signed-off-by: Dongli Zhang <dongli.zhang@oracle.com> --- drivers/block/xen-blkback/xenbus.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-)