diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2016-10-06 11:39:11 +0200 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2016-10-31 00:21:43 +0200 |
commit | d3c3589b8b3cd4fabf4cd137facb42a7fb36bd7f (patch) | |
tree | d71957ed6843a84c8328587604b9bdfe84363094 /tools/virtio/ringtest/virtio_ring_0_9.c | |
parent | 44d65ea1615099ae252407f2554338d450cfdb1c (diff) |
ringtest: commonize implementation of poll_avail/poll_used
Provide new primitives used_empty/avail_empty and
build poll_avail/poll_used on top of it.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'tools/virtio/ringtest/virtio_ring_0_9.c')
-rw-r--r-- | tools/virtio/ringtest/virtio_ring_0_9.c | 64 |
1 files changed, 15 insertions, 49 deletions
diff --git a/tools/virtio/ringtest/virtio_ring_0_9.c b/tools/virtio/ringtest/virtio_ring_0_9.c index 761866212aac..bbc3043b2fb1 100644 --- a/tools/virtio/ringtest/virtio_ring_0_9.c +++ b/tools/virtio/ringtest/virtio_ring_0_9.c @@ -194,24 +194,16 @@ void *get_buf(unsigned *lenp, void **bufp) return datap; } -void poll_used(void) +bool used_empty() { + unsigned short last_used_idx = guest.last_used_idx; #ifdef RING_POLL - unsigned head = (ring_size - 1) & guest.last_used_idx; + unsigned short head = last_used_idx & (ring_size - 1); + unsigned index = ring.used->ring[head].id; - for (;;) { - unsigned index = ring.used->ring[head].id; - - if ((index ^ guest.last_used_idx ^ 0x8000) & ~(ring_size - 1)) - busy_wait(); - else - break; - } + return (index ^ last_used_idx ^ 0x8000) & ~(ring_size - 1); #else - unsigned head = guest.last_used_idx; - - while (ring.used->idx == head) - busy_wait(); + return ring.used->idx == last_used_idx; #endif } @@ -224,22 +216,11 @@ void disable_call() bool enable_call() { - unsigned short last_used_idx; - - vring_used_event(&ring) = (last_used_idx = guest.last_used_idx); + vring_used_event(&ring) = guest.last_used_idx; /* Flush call index write */ /* Barrier D (for pairing) */ smp_mb(); -#ifdef RING_POLL - { - unsigned short head = last_used_idx & (ring_size - 1); - unsigned index = ring.used->ring[head].id; - - return (index ^ last_used_idx ^ 0x8000) & ~(ring_size - 1); - } -#else - return ring.used->idx == last_used_idx; -#endif + return used_empty(); } void kick_available(void) @@ -266,36 +247,21 @@ void disable_kick() bool enable_kick() { - unsigned head = host.used_idx; - - vring_avail_event(&ring) = head; + vring_avail_event(&ring) = host.used_idx; /* Barrier C (for pairing) */ smp_mb(); -#ifdef RING_POLL - { - unsigned index = ring.avail->ring[head & (ring_size - 1)]; - - return (index ^ head ^ 0x8000) & ~(ring_size - 1); - } -#else - return head == ring.avail->idx; -#endif + return avail_empty(); } -void poll_avail(void) +bool avail_empty() { unsigned head = host.used_idx; #ifdef RING_POLL - for (;;) { - unsigned index = ring.avail->ring[head & (ring_size - 1)]; - if ((index ^ head ^ 0x8000) & ~(ring_size - 1)) - busy_wait(); - else - break; - } + unsigned index = ring.avail->ring[head & (ring_size - 1)]; + + return ((index ^ head ^ 0x8000) & ~(ring_size - 1)); #else - while (ring.avail->idx == head) - busy_wait(); + return head == ring.avail->idx; #endif } |