From c5f841f1780dad7efb7eca092f60742d47f47d25 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Mon, 30 Mar 2009 21:55:22 -0600 Subject: [PATCH] virtio: more neatening of virtio_ring macros. Impact: cleanup Roel Kluin drew attention to these macros with his patch: here I neaten them a little further: 1) Add a comment on what START_USE and END_USE are checking, 2) Brackets around _vq in BAD_RING, 3) Neaten formatting for START_USE so it's less than 80 cols. Signed-off-by: Rusty Russell --- drivers/virtio/virtio_ring.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 12273bf9b3b2..5c52369ab9bb 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -24,9 +24,15 @@ #ifdef DEBUG /* For development, we want to crash whenever the ring is screwed. */ #define BAD_RING(_vq, fmt...) \ - do { dev_err(&_vq->vq.vdev->dev, fmt); BUG(); } while(0) -#define START_USE(_vq) \ - do { if ((_vq)->in_use) panic("in_use = %i\n", (_vq)->in_use); (_vq)->in_use = __LINE__; mb(); } while(0) + do { dev_err(&(_vq)->vq.vdev->dev, fmt); BUG(); } while(0) +/* Caller is supposed to guarantee no reentry. */ +#define START_USE(_vq) \ + do { \ + if ((_vq)->in_use) \ + panic("in_use = %i\n", (_vq)->in_use); \ + (_vq)->in_use = __LINE__; \ + mb(); \ + } while(0) #define END_USE(_vq) \ do { BUG_ON(!(_vq)->in_use); (_vq)->in_use = 0; mb(); } while(0) #else