X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;ds=sidebyside;f=src%2Fmisc%2Fblock.c;h=1d06fec1467f52d47116daecc8c1d86a11b3d6e3;hb=54bac7d87af582675d09464790731a38dd86582a;hp=6cefb243d8880568a3c9797eec6dc2782fec1d44;hpb=3ac52259dd7a91b6b0508856e9fcb1111815ad64;p=vlc diff --git a/src/misc/block.c b/src/misc/block.c index 6cefb243d8..1d06fec146 100644 --- a/src/misc/block.c +++ b/src/misc/block.c @@ -31,6 +31,7 @@ #include #include #include +#include #include "vlc_block.h" /** @@ -64,6 +65,7 @@ void block_Init( block_t *restrict b, void *buf, size_t size ) b->i_dts = VLC_TS_INVALID; b->i_length = 0; b->i_rate = 0; + b->i_nb_samples = 0; b->p_buffer = buf; b->i_buffer = size; #ifndef NDEBUG @@ -78,18 +80,19 @@ static void BlockRelease( block_t *p_block ) static void BlockMetaCopy( block_t *restrict out, const block_t *in ) { + out->p_next = in->p_next; out->i_dts = in->i_dts; out->i_pts = in->i_pts; out->i_flags = in->i_flags; out->i_length = in->i_length; out->i_rate = in->i_rate; - out->i_samples = in->i_samples; + out->i_nb_samples = in->i_nb_samples; } -/* Memory alignment */ +/* Memory alignment (must be a multiple of sizeof(void*) and a power of two) */ #define BLOCK_ALIGN 16 -/* Initial size of reserved header and footer */ -#define BLOCK_PADDING_SIZE 32 +/* Initial reserved header and footer size (must be multiple of alignment) */ +#define BLOCK_PADDING 32 /* Maximum size of reserved footer before we release with realloc() */ #define BLOCK_WASTE_SIZE 2048 @@ -97,24 +100,41 @@ block_t *block_Alloc( size_t i_size ) { /* We do only one malloc * TODO: bench if doing 2 malloc but keeping a pool of buffer is better - * TODO: use memalign - * 16 -> align on 16 - * 2 * BLOCK_PADDING_SIZE -> pre + post padding + * 2 * BLOCK_PADDING -> pre + post padding */ - const size_t i_alloc = i_size + 2 * BLOCK_PADDING_SIZE + BLOCK_ALIGN; - block_sys_t *p_sys = malloc( sizeof( *p_sys ) + i_alloc ); + block_sys_t *p_sys; + uint8_t *buf; + +#define ALIGN(x) (((x) + BLOCK_ALIGN - 1) & ~(BLOCK_ALIGN - 1)) +#if 0 /*def HAVE_POSIX_MEMALIGN */ + /* posix_memalign(,16,) is much slower than malloc() on glibc. + * -- Courmisch, September 2009, glibc 2.5 & 2.9 */ + const size_t i_alloc = ALIGN(sizeof(*p_sys)) + (2 * BLOCK_PADDING) + + ALIGN(i_size); + void *ptr; + + if( posix_memalign( &ptr, BLOCK_ALIGN, i_alloc ) ) + return NULL; + + p_sys = ptr; + buf = p_sys->p_allocated_buffer + (-sizeof(*p_sys) & (BLOCK_ALIGN - 1)); +#else + const size_t i_alloc = sizeof(*p_sys) + BLOCK_ALIGN + (2 * BLOCK_PADDING) + + ALIGN(i_size); + p_sys = malloc( i_alloc ); if( p_sys == NULL ) return NULL; - /* Fill opaque data */ - p_sys->i_allocated_buffer = i_alloc; + buf = (void *)ALIGN((uintptr_t)p_sys->p_allocated_buffer); - block_Init( &p_sys->self, p_sys->p_allocated_buffer + BLOCK_PADDING_SIZE - + BLOCK_ALIGN - - ((uintptr_t)p_sys->p_allocated_buffer % BLOCK_ALIGN), - i_size ); +#endif + buf += BLOCK_PADDING; + + block_Init( &p_sys->self, buf, i_size ); p_sys->self.pf_release = BlockRelease; + /* Fill opaque data */ + p_sys->i_allocated_buffer = i_alloc - sizeof(*p_sys); return &p_sys->self; } @@ -193,9 +213,8 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) * minimize the payload size for memory copy. */ assert( i_prebody >= 0 ); if( (size_t)(p_block->p_buffer - p_start) < (size_t)i_prebody - || (size_t)(p_end - p_block->p_buffer) < p_block->i_buffer + i_body ) + || (size_t)(p_end - p_block->p_buffer) < i_body ) { - /* FIXME: this is really dumb, we should use realloc() */ block_t *p_rea = block_Alloc( requested ); if( p_rea ) { @@ -205,8 +224,27 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) memcpy( p_rea->p_buffer, p_block->p_buffer, p_block->i_buffer ); } block_Release( p_block ); + if( p_rea == NULL ) + return NULL; p_block = p_rea; } + else + /* We have a very large reserved footer now? Release some of it. + * XXX it might not preserve the alignment of p_buffer */ + if( p_end - (p_block->p_buffer + i_body) > BLOCK_WASTE_SIZE ) + { + block_t *p_rea = block_Alloc( requested ); + if( p_rea ) + { + BlockMetaCopy( p_rea, p_block ); + p_rea->p_buffer += i_prebody; + p_rea->i_buffer -= i_prebody; + memcpy( p_rea->p_buffer, p_block->p_buffer, p_block->i_buffer ); + block_Release( p_block ); + p_block = p_rea; + } + } + /* NOTE: p_start and p_end are corrupted from this point */ /* Third, expand payload */ @@ -223,23 +261,6 @@ block_t *block_Realloc( block_t *p_block, ssize_t i_prebody, size_t i_body ) /* Expand payload to requested size */ p_block->i_buffer = i_body; - /* We have a very large reserved footer now? Release some of it. - * XXX it might not preserve the alignment of p_buffer */ - if( (p_sys->p_allocated_buffer + p_sys->i_allocated_buffer) - - (p_block->p_buffer + p_block->i_buffer) > BLOCK_WASTE_SIZE ) - { - const ptrdiff_t i_prebody = p_block->p_buffer - p_sys->p_allocated_buffer; - const size_t i_new = i_prebody + p_block->i_buffer + 1 * BLOCK_PADDING_SIZE; - block_sys_t *p_new = realloc( p_sys, sizeof (*p_sys) + i_new ); - - if( p_new != NULL ) - { - p_sys = p_new; - p_sys->i_allocated_buffer = i_new; - p_block = &p_sys->self; - p_block->p_buffer = &p_sys->p_allocated_buffer[i_prebody]; - } - } return p_block; } @@ -487,23 +508,27 @@ void block_FifoRelease( block_fifo_t *p_fifo ) void block_FifoEmpty( block_fifo_t *p_fifo ) { - block_t *b; + block_t *block; vlc_mutex_lock( &p_fifo->lock ); - for( b = p_fifo->p_first; b != NULL; ) + block = p_fifo->p_first; + if (block != NULL) { - block_t *p_next; - - p_next = b->p_next; - block_Release( b ); - b = p_next; + p_fifo->i_depth = p_fifo->i_size = 0; + p_fifo->p_first = NULL; + p_fifo->pp_last = &p_fifo->p_first; } - - p_fifo->i_depth = p_fifo->i_size = 0; - p_fifo->p_first = NULL; - p_fifo->pp_last = &p_fifo->p_first; vlc_cond_broadcast( &p_fifo->wait_room ); vlc_mutex_unlock( &p_fifo->lock ); + + while (block != NULL) + { + block_t *buf; + + buf = block->p_next; + block_Release (block); + block = buf; + } } /** @@ -541,25 +566,29 @@ void block_FifoPace (block_fifo_t *fifo, size_t max_depth, size_t max_size) * Immediately queue one block at the end of a FIFO. * @param fifo queue * @param block head of a block list to queue (may be NULL) + * @return total number of bytes appended to the queue */ size_t block_FifoPut( block_fifo_t *p_fifo, block_t *p_block ) { - size_t i_size = 0; - vlc_mutex_lock( &p_fifo->lock ); + size_t i_size = 0, i_depth = 0; + block_t *p_last; - while (p_block != NULL) + if (p_block == NULL) + return 0; + for (p_last = p_block; ; p_last = p_last->p_next) { - i_size += p_block->i_buffer; - - *p_fifo->pp_last = p_block; - p_fifo->pp_last = &p_block->p_next; - p_fifo->i_depth++; - p_fifo->i_size += p_block->i_buffer; - - p_block = p_block->p_next; + i_size += p_last->i_buffer; + i_depth++; + if (!p_last->p_next) + break; } - /* We queued one block: wake up one read-waiting thread */ + vlc_mutex_lock (&p_fifo->lock); + *p_fifo->pp_last = p_block; + p_fifo->pp_last = &p_last->p_next; + p_fifo->i_depth += i_depth; + p_fifo->i_size += i_size; + /* We queued at least one block: wake up one read-waiting thread */ vlc_cond_signal( &p_fifo->wait ); vlc_mutex_unlock( &p_fifo->lock ); @@ -575,6 +604,12 @@ void block_FifoWake( block_fifo_t *p_fifo ) vlc_mutex_unlock( &p_fifo->lock ); } +/** + * Dequeue the first block from the FIFO. If necessary, wait until there is + * one block in the queue. This function is (always) cancellation point. + * + * @return a valid block, or NULL if block_FifoWake() was called. + */ block_t *block_FifoGet( block_fifo_t *p_fifo ) { block_t *b; @@ -617,6 +652,17 @@ block_t *block_FifoGet( block_fifo_t *p_fifo ) return b; } +/** + * Peeks the first block in the FIFO. + * If necessary, wait until there is one block. + * This function is (always) a cancellation point. + * + * @warning This function leaves the block in the FIFO. + * You need to protect against concurrent threads who could dequeue the block. + * Preferrably, there should be only one thread reading from the FIFO. + * + * @return a valid block. + */ block_t *block_FifoShow( block_fifo_t *p_fifo ) { block_t *b;