From: Paolo Bonzini <pbonzini@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: Wanlong Gao <gaowanlong@cn.fujitsu.com>,
asias@redhat.com, Rusty Russell <rusty@rustcorp.com.au>,
mst@redhat.com, kvm@vger.kernel.org,
virtualization@lists.linux-foundation.org
Subject: [RFC PATCH 2/8] virtio-blk: reorganize virtblk_add_req
Date: Thu, 7 Feb 2013 13:22:26 +0100 [thread overview]
Message-ID: <1360239752-2470-3-git-send-email-pbonzini@redhat.com> (raw)
In-Reply-To: <1360239752-2470-1-git-send-email-pbonzini@redhat.com>
Right now, both virtblk_add_req and virtblk_add_req_wait call
virtqueue_add_buf. To prepare for the next patches, abstract the call
to virtqueue_add_buf into a new function __virtblk_add_req, and include
the waiting logic directly in virtblk_add_req.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
drivers/block/virtio_blk.c | 55 ++++++++++++++++----------------------------
1 files changed, 20 insertions(+), 35 deletions(-)
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 8ad21a2..fd8a689 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -100,50 +100,39 @@ static inline struct virtblk_req *virtblk_alloc_req(struct virtio_blk *vblk,
return vbr;
}
-static void virtblk_add_buf_wait(struct virtio_blk *vblk,
- struct virtblk_req *vbr,
- unsigned long out,
- unsigned long in)
+static inline int __virtblk_add_req(struct virtqueue *vq,
+ struct virtblk_req *vbr,
+ unsigned long out,
+ unsigned long in)
{
+ return virtqueue_add_buf(vq, vbr->sg, out, in, vbr, GFP_ATOMIC);
+}
+
+static void virtblk_add_req(struct virtblk_req *vbr,
+ unsigned int out, unsigned int in)
+{
+ struct virtio_blk *vblk = vbr->vblk;
DEFINE_WAIT(wait);
+ int ret;
- for (;;) {
+ spin_lock_irq(vblk->disk->queue->queue_lock);
+ while (unlikely((ret = __virtblk_add_req(vblk->vq, vbr,
+ out, in)) < 0)) {
prepare_to_wait_exclusive(&vblk->queue_wait, &wait,
TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(vblk->disk->queue->queue_lock);
+ io_schedule();
spin_lock_irq(vblk->disk->queue->queue_lock);
- if (virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
- GFP_ATOMIC) < 0) {
- spin_unlock_irq(vblk->disk->queue->queue_lock);
- io_schedule();
- } else {
- virtqueue_kick(vblk->vq);
- spin_unlock_irq(vblk->disk->queue->queue_lock);
- break;
- }
+ finish_wait(&vblk->queue_wait, &wait);
}
- finish_wait(&vblk->queue_wait, &wait);
-}
-
-static inline void virtblk_add_req(struct virtblk_req *vbr,
- unsigned int out, unsigned int in)
-{
- struct virtio_blk *vblk = vbr->vblk;
-
- spin_lock_irq(vblk->disk->queue->queue_lock);
- if (unlikely(virtqueue_add_buf(vblk->vq, vbr->sg, out, in, vbr,
- GFP_ATOMIC) < 0)) {
- spin_unlock_irq(vblk->disk->queue->queue_lock);
- virtblk_add_buf_wait(vblk, vbr, out, in);
- return;
- }
virtqueue_kick(vblk->vq);
spin_unlock_irq(vblk->disk->queue->queue_lock);
}
-static int virtblk_bio_send_flush(struct virtblk_req *vbr)
+static void virtblk_bio_send_flush(struct virtblk_req *vbr)
{
unsigned int out = 0, in = 0;
@@ -155,11 +144,9 @@ static int virtblk_bio_send_flush(struct virtblk_req *vbr)
sg_set_buf(&vbr->sg[out + in++], &vbr->status, sizeof(vbr->status));
virtblk_add_req(vbr, out, in);
-
- return 0;
}
-static int virtblk_bio_send_data(struct virtblk_req *vbr)
+static void virtblk_bio_send_data(struct virtblk_req *vbr)
{
struct virtio_blk *vblk = vbr->vblk;
unsigned int num, out = 0, in = 0;
@@ -188,8 +175,6 @@ static int virtblk_bio_send_data(struct virtblk_req *vbr)
}
virtblk_add_req(vbr, out, in);
-
- return 0;
}
static void virtblk_bio_send_data_work(struct work_struct *work)
--
1.7.1
next prev parent reply other threads:[~2013-02-07 12:22 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-07 12:22 [RFC PATCH 0/8] virtio: new API for addition of buffers, scatterlist changes Paolo Bonzini
2013-02-07 12:22 ` [RFC PATCH 1/8] virtio: add functions for piecewise addition of buffers Paolo Bonzini
2013-02-07 12:22 ` Paolo Bonzini [this message]
2013-02-07 12:22 ` [RFC PATCH 3/8] virtio-blk: use virtqueue_start_buf on bio path Paolo Bonzini
2013-02-07 12:22 ` [RFC PATCH 4/8] virtio-blk: use virtqueue_start_buf on req path Paolo Bonzini
2013-02-07 12:22 ` [RFC PATCH 5/8] scatterlist: introduce sg_unmark_end Paolo Bonzini
2013-02-07 12:35 ` Jens Axboe
2013-02-07 12:22 ` [RFC PATCH 6/8] virtio-net: unmark scatterlist ending after virtqueue_add_buf Paolo Bonzini
2013-02-07 12:22 ` [RFC PATCH 7/8] virtio-scsi: use virtqueue_start_buf Paolo Bonzini
2013-02-07 12:22 ` [RFC PATCH 8/8] virtio: reimplement virtqueue_add_buf using new functions Paolo Bonzini
2013-02-07 13:09 ` [RFC PATCH 0/8] virtio: new API for addition of buffers, scatterlist changes Michael S. Tsirkin
2013-02-07 13:14 ` Paolo Bonzini
2013-02-07 13:23 ` Michael S. Tsirkin
2013-02-07 13:20 ` Paolo Bonzini
2013-02-07 13:31 ` Michael S. Tsirkin
2013-02-07 13:30 ` Paolo Bonzini
2013-02-08 4:05 ` Rusty Russell
2013-02-08 6:35 ` Paolo Bonzini
2013-02-08 11:52 ` Jens Axboe
2013-02-13 9:46 ` Rusty Russell
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1360239752-2470-3-git-send-email-pbonzini@redhat.com \
--to=pbonzini@redhat.com \
--cc=asias@redhat.com \
--cc=gaowanlong@cn.fujitsu.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mst@redhat.com \
--cc=rusty@rustcorp.com.au \
--cc=virtualization@lists.linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).