diff options
| -rw-r--r-- | src/gallium/auxiliary/Makefile | 1 | ||||
| -rw-r--r-- | src/gallium/auxiliary/SConscript | 1 | ||||
| -rw-r--r-- | src/gallium/auxiliary/util/u_ringbuffer.c | 145 | ||||
| -rw-r--r-- | src/gallium/auxiliary/util/u_ringbuffer.h | 29 |
4 files changed, 176 insertions, 0 deletions
diff --git a/src/gallium/auxiliary/Makefile b/src/gallium/auxiliary/Makefile index e3af41c6e04..8f937e3b4e9 100644 --- a/src/gallium/auxiliary/Makefile +++ b/src/gallium/auxiliary/Makefile @@ -111,6 +111,7 @@ C_SOURCES = \ util/u_math.c \ util/u_mm.c \ util/u_rect.c \ + util/u_ringbuffer.c \ util/u_simple_shaders.c \ util/u_snprintf.c \ util/u_stream_stdc.c \ diff --git a/src/gallium/auxiliary/SConscript b/src/gallium/auxiliary/SConscript index 782eb533863..f957090b5fb 100644 --- a/src/gallium/auxiliary/SConscript +++ b/src/gallium/auxiliary/SConscript @@ -147,6 +147,7 @@ source = [ 'util/u_math.c', 'util/u_mm.c', 'util/u_rect.c', + 'util/u_ringbuffer.c', 'util/u_simple_shaders.c', 'util/u_snprintf.c', 'util/u_stream_stdc.c', diff --git a/src/gallium/auxiliary/util/u_ringbuffer.c b/src/gallium/auxiliary/util/u_ringbuffer.c new file mode 100644 index 00000000000..3f43a19e018 --- /dev/null +++ b/src/gallium/auxiliary/util/u_ringbuffer.c @@ -0,0 +1,145 @@ + +#include "pipe/p_thread.h" +#include "pipe/p_defines.h" +#include "util/u_ringbuffer.h" +#include "util/u_math.h" +#include "util/u_memory.h" + +/* Generic ringbuffer: + */ +struct util_ringbuffer +{ + struct util_packet *buf; + unsigned mask; + + /* Can this be done with atomic variables?? + */ + unsigned head; + unsigned tail; + pipe_condvar change; + pipe_mutex mutex; +}; + + +struct util_ringbuffer *util_ringbuffer_create( unsigned dwords ) +{ + struct util_ringbuffer *ring = CALLOC_STRUCT(util_ringbuffer); + if (ring == NULL) + return NULL; + + assert(util_is_power_of_two(dwords)); + + ring->buf = MALLOC( dwords * sizeof(unsigned) ); + if (ring->buf == NULL) + goto fail; + + ring->mask = dwords - 1; + + pipe_condvar_init(ring->change); + pipe_mutex_init(ring->mutex); + return ring; + +fail: + FREE(ring->buf); + FREE(ring); + return NULL; +} + +void util_ringbuffer_destroy( struct util_ringbuffer *ring ) +{ + pipe_condvar_destroy(ring->change); + pipe_mutex_destroy(ring->mutex); + FREE(ring->buf); + FREE(ring); +} + +static INLINE unsigned util_ringbuffer_space( const struct util_ringbuffer *ring ) +{ + return (ring->tail - (ring->head + 1)) & ring->mask; +} + +void util_ringbuffer_enqueue( struct util_ringbuffer *ring, + const struct util_packet *packet ) +{ + unsigned i; + + /* XXX: over-reliance on mutexes, etc: + */ + pipe_mutex_lock(ring->mutex); + + /* Wait for free space: + */ + while (util_ringbuffer_space(ring) < packet->dwords) + pipe_condvar_wait(ring->change, ring->mutex); + + /* Copy data to ring: + */ + for (i = 0; i < packet->dwords; i++) { + + /* Copy all dwords of the packet. Note we're abusing the + * typesystem a little - we're being passed a pointer to + * something, but probably not an array of packet structs: + */ + ring->buf[ring->head] = packet[i]; + ring->head++; + ring->head &= ring->mask; + } + + /* Signal change: + */ + pipe_condvar_signal(ring->change); + pipe_mutex_unlock(ring->mutex); +} + +enum pipe_error util_ringbuffer_dequeue( struct util_ringbuffer *ring, + struct util_packet *packet, + unsigned max_dwords, + boolean wait ) +{ + const struct util_packet *ring_packet; + unsigned i; + int ret = PIPE_OK; + + /* XXX: over-reliance on mutexes, etc: + */ + pipe_mutex_lock(ring->mutex); + + /* Wait for free space: + */ + if (wait) { + while (util_ringbuffer_space(ring) == 0) + pipe_condvar_wait(ring->change, ring->mutex); + } + else { + if (util_ringbuffer_space(ring) == 0) { + ret = PIPE_ERROR_OUT_OF_MEMORY; + goto out; + } + } + + ring_packet = &ring->buf[ring->tail]; + + /* Both of these are considered bugs. Raise an assert on debug builds. + */ + if (ring_packet->dwords > ring->mask + 1 - util_ringbuffer_space(ring) || + ring_packet->dwords > max_dwords) { + assert(0); + ret = PIPE_ERROR_BAD_INPUT; + goto out; + } + + /* Copy data from ring: + */ + for (i = 0; i < ring_packet->dwords; i++) { + packet[i] = ring->buf[ring->tail]; + ring->tail++; + ring->tail &= ring->mask; + } + +out: + /* Signal change: + */ + pipe_condvar_signal(ring->change); + pipe_mutex_unlock(ring->mutex); + return ret; +} diff --git a/src/gallium/auxiliary/util/u_ringbuffer.h b/src/gallium/auxiliary/util/u_ringbuffer.h new file mode 100644 index 00000000000..85f0ad6c1f6 --- /dev/null +++ b/src/gallium/auxiliary/util/u_ringbuffer.h @@ -0,0 +1,29 @@ + +#ifndef UTIL_RINGBUFFER_H +#define UTIL_RINGBUFFER_H + +#include "pipe/p_compiler.h" +#include "pipe/p_defines.h" /* only for pipe_error! */ + +/* Generic header + */ +struct util_packet { + unsigned dwords:8; + unsigned data24:24; +}; + +struct util_ringbuffer; + +struct util_ringbuffer *util_ringbuffer_create( unsigned dwords ); + +void util_ringbuffer_destroy( struct util_ringbuffer *ring ); + +void util_ringbuffer_enqueue( struct util_ringbuffer *ring, + const struct util_packet *packet ); + +enum pipe_error util_ringbuffer_dequeue( struct util_ringbuffer *ring, + struct util_packet *packet, + unsigned max_dwords, + boolean wait ); + +#endif |