31 lines
907 B
Diff
31 lines
907 B
Diff
From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Wed, 13 Jun 2012 16:56:31 +0200
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Subject: [03/12] [SCSI] virtio-scsi: unlock during kick
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commit b5ee8f2802c559fccb177c0a117f5cd56c1049cc upstream.
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Separate virtqueue_kick_prepare from virtqueue_notify, so that the
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expensive vmexit is done without holding the lock.
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Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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Signed-off-by: James Bottomley <JBottomley@Parallels.com>
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---
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drivers/scsi/virtio_scsi.c | 4 +++-
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1 file changed, 3 insertions(+), 1 deletion(-)
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--- a/drivers/scsi/virtio_scsi.c
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+++ b/drivers/scsi/virtio_scsi.c
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@@ -264,9 +264,11 @@ static int virtscsi_kick_cmd(struct virt
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ret = virtqueue_add_buf_gfp(vq, vscsi->sg, out_num, in_num, cmd, gfp);
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if (ret >= 0)
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- virtqueue_kick(vq);
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+ ret = virtqueue_kick_prepare(vq);
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spin_unlock_irqrestore(&vscsi->vq_lock, flags);
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+ if (ret > 0)
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+ virtqueue_notify(vq);
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return ret;
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}
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