/**************************************************************************
*
* Copyright 2007-2008 VMware, Inc.
* All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sub license, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial portions
* of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
* IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
**************************************************************************/
/**
* \file
* Buffer cache.
*
* \author Jose Fonseca <jfonseca-at-vmware-dot-com>
* \author Thomas Hellström <thellstom-at-vmware-dot-com>
*/
#include "pipe/p_compiler.h"
#include "util/u_debug.h"
#include "os/os_thread.h"
#include "util/u_memory.h"
#include "util/list.h"
#include "util/u_time.h"
#include "pb_buffer.h"
#include "pb_bufmgr.h"
/**
* Convenience macro (type safe).
*/
#define SUPER(__derived) (&(__derived)->base)
struct pb_cache_manager;
/**
* Wrapper around a pipe buffer which adds delayed destruction.
*/
struct pb_cache_buffer
{
struct pb_buffer base;
struct pb_buffer *buffer;
struct pb_cache_manager *mgr;
/** Caching time interval */
int64_t start, end;
struct list_head head;
};
struct pb_cache_manager
{
struct pb_manager base;
struct pb_manager *provider;
unsigned usecs;
pipe_mutex mutex;
struct list_head delayed;
pb_size numDelayed;
float size_factor;
unsigned bypass_usage;
uint64_t cache_size, max_cache_size;
};
static INLINE struct pb_cache_buffer *
pb_cache_buffer(struct pb_buffer *buf)
{
return (struct pb_cache_buffer *)buf;
}
static INLINE struct pb_cache_manager *
pb_cache_manager(struct pb_manager *mgr)
{
return (struct pb_cache_manager *)mgr;
}
/**
* Actually destroy the buffer.
*/
static INLINE void
_pb_cache_buffer_destroy(struct pb_cache_buffer *buf)
{
struct pb_cache_manager *mgr = buf->mgr;
LIST_DEL(&buf->head);
--mgr->numDelayed;
mgr->cache_size -= buf->base.size;
assert(!pipe_is_referenced
(&buf
->base.
reference)); pb_reference(&buf->buffer, NULL);
FREE(buf);
}
/**
* Free as many cache buffers from the list head as possible.
*/
static void
_pb_cache_buffer_list_check_free(struct pb_cache_manager *mgr)
{
struct list_head *curr, *next;
struct pb_cache_buffer *buf;
int64_t now;
now = os_time_get();
curr = mgr->delayed.next;
next = curr->next;
while(curr != &mgr->delayed) {
buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
if(!os_time_timeout(buf->start, buf->end, now))
break;
_pb_cache_buffer_destroy(buf);
curr = next;
next = curr->next;
}
}
static void
pb_cache_buffer_destroy(struct pb_buffer *_buf)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
struct pb_cache_manager *mgr = buf->mgr;
pipe_mutex_lock(mgr->mutex);
assert(!pipe_is_referenced
(&buf
->base.
reference));
_pb_cache_buffer_list_check_free(mgr);
/* Directly release any buffer that exceeds the limit. */
if (mgr->cache_size + buf->base.size > mgr->max_cache_size) {
pb_reference(&buf->buffer, NULL);
FREE(buf);
pipe_mutex_unlock(mgr->mutex);
return;
}
buf->start = os_time_get();
buf->end = buf->start + mgr->usecs;
LIST_ADDTAIL(&buf->head, &mgr->delayed);
++mgr->numDelayed;
mgr->cache_size += buf->base.size;
pipe_mutex_unlock(mgr->mutex);
}
static void *
pb_cache_buffer_map(struct pb_buffer *_buf,
unsigned flags, void *flush_ctx)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
return pb_map(buf->buffer, flags, flush_ctx);
}
static void
pb_cache_buffer_unmap(struct pb_buffer *_buf)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
pb_unmap(buf->buffer);
}
static enum pipe_error
pb_cache_buffer_validate(struct pb_buffer *_buf,
struct pb_validate *vl,
unsigned flags)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
return pb_validate(buf->buffer, vl, flags);
}
static void
pb_cache_buffer_fence(struct pb_buffer *_buf,
struct pipe_fence_handle *fence)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
pb_fence(buf->buffer, fence);
}
static void
pb_cache_buffer_get_base_buffer(struct pb_buffer *_buf,
struct pb_buffer **base_buf,
pb_size *offset)
{
struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
pb_get_base_buffer(buf->buffer, base_buf, offset);
}
const struct pb_vtbl
pb_cache_buffer_vtbl = {
pb_cache_buffer_destroy,
pb_cache_buffer_map,
pb_cache_buffer_unmap,
pb_cache_buffer_validate,
pb_cache_buffer_fence,
pb_cache_buffer_get_base_buffer
};
static INLINE int
pb_cache_is_buffer_compat(struct pb_cache_buffer *buf,
pb_size size,
const struct pb_desc *desc)
{
if (desc->usage & buf->mgr->bypass_usage)
return 0;
if(buf->base.size < size)
return 0;
/* be lenient with size */
if(buf->base.size > (unsigned) (buf->mgr->size_factor * size))
return 0;
if(!pb_check_alignment(desc->alignment, buf->base.alignment))
return 0;
if(!pb_check_usage(desc->usage, buf->base.usage))
return 0;
if (buf->mgr->provider->is_buffer_busy) {
if (buf->mgr->provider->is_buffer_busy(buf->mgr->provider, buf->buffer))
return -1;
} else {
void *ptr = pb_map(buf->buffer, PB_USAGE_DONTBLOCK, NULL);
if (!ptr)
return -1;
pb_unmap(buf->buffer);
}
return 1;
}
static struct pb_buffer *
pb_cache_manager_create_buffer(struct pb_manager *_mgr,
pb_size size,
const struct pb_desc *desc)
{
struct pb_cache_manager *mgr = pb_cache_manager(_mgr);
struct pb_cache_buffer *buf;
struct pb_cache_buffer *curr_buf;
struct list_head *curr, *next;
int64_t now;
int ret = 0;
pipe_mutex_lock(mgr->mutex);
buf = NULL;
curr = mgr->delayed.next;
next = curr->next;
/* search in the expired buffers, freeing them in the process */
now = os_time_get();
while(curr != &mgr->delayed) {
curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
if(!buf && (ret = pb_cache_is_buffer_compat(curr_buf, size, desc) > 0))
buf = curr_buf;
else if(os_time_timeout(curr_buf->start, curr_buf->end, now))
_pb_cache_buffer_destroy(curr_buf);
else
/* This buffer (and all hereafter) are still hot in cache */
break;
if (ret == -1)
break;
curr = next;
next = curr->next;
}
/* keep searching in the hot buffers */
if(!buf && ret != -1) {
while(curr != &mgr->delayed) {
curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
ret = pb_cache_is_buffer_compat(curr_buf, size, desc);
if (ret > 0) {
buf = curr_buf;
break;
}
if (ret == -1)
break;
/* no need to check the timeout here */
curr = next;
next = curr->next;
}
}
if(buf) {
mgr->cache_size -= buf->base.size;
LIST_DEL(&buf->head);
--mgr->numDelayed;
pipe_mutex_unlock(mgr->mutex);
/* Increase refcount */
pipe_reference_init(&buf->base.reference, 1);
return &buf->base;
}
pipe_mutex_unlock(mgr->mutex);
buf = CALLOC_STRUCT(pb_cache_buffer);
if(!buf)
return NULL;
buf->buffer = mgr->provider->create_buffer(mgr->provider, size, desc);
/* Empty the cache and try again. */
if (!buf->buffer) {
mgr->base.flush(&mgr->base);
buf->buffer = mgr->provider->create_buffer(mgr->provider, size, desc);
}
if(!buf->buffer) {
FREE(buf);
return NULL;
}
assert(pipe_is_referenced
(&buf
->buffer
->reference
)); assert(pb_check_alignment
(desc
->alignment
, buf
->buffer
->alignment
)); assert(pb_check_usage
(desc
->usage
& ~mgr
->bypass_usage
, buf
->buffer
->usage
)); assert(buf
->buffer
->size
>= size
);
pipe_reference_init(&buf->base.reference, 1);
buf->base.alignment = buf->buffer->alignment;
buf->base.usage = buf->buffer->usage;
buf->base.size = buf->buffer->size;
buf->base.vtbl = &pb_cache_buffer_vtbl;
buf->mgr = mgr;
return &buf->base;
}
static void
pb_cache_manager_flush(struct pb_manager *_mgr)
{
struct pb_cache_manager *mgr = pb_cache_manager(_mgr);
struct list_head *curr, *next;
struct pb_cache_buffer *buf;
pipe_mutex_lock(mgr->mutex);
curr = mgr->delayed.next;
next = curr->next;
while(curr != &mgr->delayed) {
buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
_pb_cache_buffer_destroy(buf);
curr = next;
next = curr->next;
}
pipe_mutex_unlock(mgr->mutex);
if(mgr->provider->flush)
mgr->provider->flush(mgr->provider);
}
static void
pb_cache_manager_destroy(struct pb_manager *mgr)
{
pb_cache_manager_flush(mgr);
FREE(mgr);
}
/**
* Create a caching buffer manager
*
* @param provider The buffer manager to which cache miss buffer requests
* should be redirected.
* @param usecs Unused buffers may be released from the cache after this
* time
* @param size_factor Declare buffers that are size_factor times bigger than
* the requested size as cache hits.
* @param bypass_usage Bitmask. If (requested usage & bypass_usage) != 0,
* buffer allocation requests are redirected to the provider.
* @param maximum_cache_size Maximum size of all unused buffers the cache can
* hold.
*/
struct pb_manager *
pb_cache_manager_create(struct pb_manager *provider,
unsigned usecs,
float size_factor,
unsigned bypass_usage,
uint64_t maximum_cache_size)
{
struct pb_cache_manager *mgr;
if(!provider)
return NULL;
mgr = CALLOC_STRUCT(pb_cache_manager);
if (!mgr)
return NULL;
mgr->base.destroy = pb_cache_manager_destroy;
mgr->base.create_buffer = pb_cache_manager_create_buffer;
mgr->base.flush = pb_cache_manager_flush;
mgr->provider = provider;
mgr->usecs = usecs;
mgr->size_factor = size_factor;
mgr->bypass_usage = bypass_usage;
LIST_INITHEAD(&mgr->delayed);
mgr->numDelayed = 0;
mgr->max_cache_size = maximum_cache_size;
pipe_mutex_init(mgr->mutex);
return &mgr->base;
}