From d3c3589b8b3cd4fabf4cd137facb42a7fb36bd7f Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 6 Oct 2016 11:39:11 +0200 Subject: [PATCH] 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 Signed-off-by: Michael S. Tsirkin --- tools/virtio/ringtest/main.c | 12 +++++ tools/virtio/ringtest/main.h | 4 +- tools/virtio/ringtest/noring.c | 6 ++- tools/virtio/ringtest/ptr_ring.c | 22 ++------- tools/virtio/ringtest/ring.c | 18 +++---- tools/virtio/ringtest/virtio_ring_0_9.c | 64 ++++++------------------- 6 files changed, 43 insertions(+), 83 deletions(-) diff --git a/tools/virtio/ringtest/main.c b/tools/virtio/ringtest/main.c index bda7f0dad981..b00ecd619969 100644 --- a/tools/virtio/ringtest/main.c +++ b/tools/virtio/ringtest/main.c @@ -96,6 +96,12 @@ void set_affinity(const char *arg) assert(!ret); } +void poll_used(void) +{ + while (used_empty()) + busy_wait(); +} + static void __attribute__((__flatten__)) run_guest(void) { int completed_before; @@ -149,6 +155,12 @@ static void __attribute__((__flatten__)) run_guest(void) } } +void poll_avail(void) +{ + while (avail_empty()) + busy_wait(); +} + static void __attribute__((__flatten__)) run_host(void) { int completed_before; diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h index 16917acb0ade..34e63cc4c572 100644 --- a/tools/virtio/ringtest/main.h +++ b/tools/virtio/ringtest/main.h @@ -56,15 +56,15 @@ void alloc_ring(void); int add_inbuf(unsigned, void *, void *); void *get_buf(unsigned *, void **); void disable_call(); +bool used_empty(); bool enable_call(); void kick_available(); -void poll_used(); /* host side */ void disable_kick(); +bool avail_empty(); bool enable_kick(); bool use_buf(unsigned *, void **); void call_used(); -void poll_avail(); /* implemented by main */ extern bool do_sleep; diff --git a/tools/virtio/ringtest/noring.c b/tools/virtio/ringtest/noring.c index eda2f4824130..b8d1c1daac7c 100644 --- a/tools/virtio/ringtest/noring.c +++ b/tools/virtio/ringtest/noring.c @@ -24,8 +24,9 @@ void *get_buf(unsigned *lenp, void **bufp) return "Buffer"; } -void poll_used(void) +bool used_empty() { + return false; } void disable_call() @@ -54,8 +55,9 @@ bool enable_kick() assert(0); } -void poll_avail(void) +bool avail_empty() { + return false; } bool use_buf(unsigned *lenp, void **bufp) diff --git a/tools/virtio/ringtest/ptr_ring.c b/tools/virtio/ringtest/ptr_ring.c index bd2ad1d3b7a9..635b07b4fdd3 100644 --- a/tools/virtio/ringtest/ptr_ring.c +++ b/tools/virtio/ringtest/ptr_ring.c @@ -133,18 +133,9 @@ void *get_buf(unsigned *lenp, void **bufp) return datap; } -void poll_used(void) +bool used_empty() { - void *b; - - do { - if (tailcnt == headcnt || __ptr_ring_full(&array)) { - b = NULL; - barrier(); - } else { - b = "Buffer\n"; - } - } while (!b); + return (tailcnt == headcnt || __ptr_ring_full(&array)); } void disable_call() @@ -173,14 +164,9 @@ bool enable_kick() assert(0); } -void poll_avail(void) +bool avail_empty() { - void *b; - - do { - barrier(); - b = __ptr_ring_peek(&array); - } while (!b); + return !__ptr_ring_peek(&array); } bool use_buf(unsigned *lenp, void **bufp) diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c index c25c8d248b6b..747c5dd47be8 100644 --- a/tools/virtio/ringtest/ring.c +++ b/tools/virtio/ringtest/ring.c @@ -163,12 +163,11 @@ void *get_buf(unsigned *lenp, void **bufp) return datap; } -void poll_used(void) +bool used_empty() { unsigned head = (ring_size - 1) & guest.last_used_idx; - while (ring[head].flags & DESC_HW) - busy_wait(); + return (ring[head].flags & DESC_HW); } void disable_call() @@ -180,13 +179,11 @@ void disable_call() bool enable_call() { - unsigned head = (ring_size - 1) & guest.last_used_idx; - event->call_index = guest.last_used_idx; /* Flush call index write */ /* Barrier D (for pairing) */ smp_mb(); - return ring[head].flags & DESC_HW; + return used_empty(); } void kick_available(void) @@ -213,20 +210,17 @@ void disable_kick() bool enable_kick() { - unsigned head = (ring_size - 1) & host.used_idx; - event->kick_index = host.used_idx; /* Barrier C (for pairing) */ smp_mb(); - return !(ring[head].flags & DESC_HW); + return avail_empty(); } -void poll_avail(void) +bool avail_empty() { unsigned head = (ring_size - 1) & host.used_idx; - while (!(ring[head].flags & DESC_HW)) - busy_wait(); + return !(ring[head].flags & DESC_HW); } bool use_buf(unsigned *lenp, void **bufp) 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 }