[PATCH v3 11/21] xen: update ring.h

Juergen Gross
2022-05-05T08:18:43Z

Update include/xen/interface/io/ring.h to its newest version.

Switch the two improper use cases of RING_HAS_UNCONSUMED_RESPONSES() to
XEN_RING_NR_UNCONSUMED_RESPONSES() in order to avoid the nasty
XEN_RING_HAS_UNCONSUMED_IS_BOOL #define.

Signed-off-by: Juergen Gross <jgross@suse.com>
---
V2:
- new patch
---
drivers/net/xen-netfront.c | 4 ++--
include/xen/interface/io/ring.h | 19 ++++++++++++++-----
2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
index af3d3de7d9fa..966bee2a6902 100644
--- a/drivers/net/xen-netfront.c
+++ b/drivers/net/xen-netfront.c
@@ -866,7 +866,7 @@ static void xennet_set_rx_rsp_cons(struct netfront_queue *queue, RING_IDX val)

spin_lock_irqsave(&queue->rx_cons_lock, flags);
queue->rx.rsp_cons = val;
- queue->rx_rsp_unconsumed = RING_HAS_UNCONSUMED_RESPONSES(&queue->rx);
+ queue->rx_rsp_unconsumed = XEN_RING_NR_UNCONSUMED_RESPONSES(&queue->rx);
spin_unlock_irqrestore(&queue->rx_cons_lock, flags);
}

@@ -1498,7 +1498,7 @@ static bool xennet_handle_rx(struct netfront_queue *queue, unsigned int *eoi)
return false;

spin_lock_irqsave(&queue->rx_cons_lock, flags);
- work_queued = RING_HAS_UNCONSUMED_RESPONSES(&queue->rx);
+ work_queued = XEN_RING_NR_UNCONSUMED_RESPONSES(&queue->rx);
if (work_queued > queue->rx_rsp_unconsumed) {
queue->rx_rsp_unconsumed = work_queued;
*eoi = 0;
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h
index 2470ec45ebb2..ba4c4274b714 100644
--- a/include/xen/interface/io/ring.h
+++ b/include/xen/interface/io/ring.h
@@ -72,9 +72,8 @@ typedef unsigned int RING_IDX;
* of the shared memory area (PAGE_SIZE, for instance). To initialise
* the front half:
*
- * mytag_front_ring_t front_ring;
- * SHARED_RING_INIT((mytag_sring_t *)shared_page);
- * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ * mytag_front_ring_t ring;
+ * XEN_FRONT_RING_INIT(&ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
*
* Initializing the back follows similarly (note that only the front
* initializes the shared ring):
@@ -146,6 +145,11 @@ struct __name##_back_ring { \

#define FRONT_RING_INIT(_r, _s, __size) FRONT_RING_ATTACH(_r, _s, 0, __size)

+#define XEN_FRONT_RING_INIT(r, s, size) do { \
+ SHARED_RING_INIT(s); \
+ FRONT_RING_INIT(r, s, size); \
+} while (0)
+
#define BACK_RING_ATTACH(_r, _s, _i, __size) do { \
(_r)->rsp_prod_pvt = (_i); \
(_r)->req_cons = (_i); \
@@ -170,16 +174,21 @@ struct __name##_back_ring { \
(RING_FREE_REQUESTS(_r) == 0)

/* Test if there are outstanding messages to be processed on a ring. */
-#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+#define XEN_RING_NR_UNCONSUMED_RESPONSES(_r) \
((_r)->sring->rsp_prod - (_r)->rsp_cons)

-#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
+#define XEN_RING_NR_UNCONSUMED_REQUESTS(_r) ({ \
unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
unsigned int rsp = RING_SIZE(_r) - \
((_r)->req_cons - (_r)->rsp_prod_pvt); \
req < rsp ? req : rsp; \
})

+#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ (!!XEN_RING_NR_UNCONSUMED_RESPONSES(_r))
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
+ (!!XEN_RING_NR_UNCONSUMED_REQUESTS(_r))
+
/* Direct access to individual ring elements, by index. */
#define RING_GET_REQUEST(_r, _idx) \
(&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
--
2.35.3