pb_bufmgr_cache.c File Reference

Buffer cache. More...

Include dependency graph for pb_bufmgr_cache.c:

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Data Structures
struct	pb_cache_buffer
	Wrapper around a pipe buffer which adds delayed destruction. More...
struct	pb_cache_manager
Defines
#define	SUPER(__derived)   (&(__derived)->base)
	Convenience macro (type safe).
Functions
static struct pb_cache_buffer *	pb_cache_buffer (struct pb_buffer *buf)
static struct pb_cache_manager *	pb_cache_manager (struct pb_manager *mgr)
static void	_pb_cache_buffer_destroy (struct pb_cache_buffer *buf)
	Actually destroy the buffer.
static void	_pb_cache_buffer_list_check_free (struct pb_cache_manager *mgr)
	Free as many cache buffers from the list head as possible.
static void	pb_cache_buffer_destroy (struct pb_buffer *_buf)
static void *	pb_cache_buffer_map (struct pb_buffer *_buf, unsigned flags)
static void	pb_cache_buffer_unmap (struct pb_buffer *_buf)
static void	pb_cache_buffer_get_base_buffer (struct pb_buffer *_buf, struct pb_buffer **base_buf, unsigned *offset)
static boolean	pb_cache_is_buffer_compat (struct pb_cache_buffer *buf, size_t size, const struct pb_desc *desc)
static struct pb_buffer *	pb_cache_manager_create_buffer (struct pb_manager *_mgr, size_t size, const struct pb_desc *desc)
static void	pb_cache_manager_flush (struct pb_manager *_mgr)
static void	pb_cache_manager_destroy (struct pb_manager *mgr)
struct pb_manager *	pb_cache_manager_create (struct pb_manager *provider, unsigned usecs)
	Time-based buffer cache.
Variables
struct pb_vtbl	pb_cache_buffer_vtbl

---

Detailed Description

Buffer cache.

Author:

José Fonseca <jrfonseca-at-tungstengraphics-dot-com>

Thomas Hellström <thomas-at-tungstengraphics-dot-com>

Definition in file pb_bufmgr_cache.c.

---

Define Documentation

#define SUPER

(

__derived

)

(&(__derived)->base)

Convenience macro (type safe).

Definition at line 52 of file pb_bufmgr_cache.c.

---

Function Documentation

static void _pb_cache_buffer_destroy

(

struct pb_cache_buffer *

buf

)

[static]

Actually destroy the buffer.

Definition at line 109 of file pb_bufmgr_cache.c.

References assert, pb_buffer::base, pb_cache_buffer::base, pb_cache_buffer::buffer, FREE, pb_cache_buffer::head, LIST_DEL, pb_cache_buffer::mgr, pb_cache_manager::numDelayed, pb_reference(), and pipe_buffer::refcount.

{
   struct pb_cache_manager *mgr = buf->mgr;

   LIST_DEL(&buf->head);
   assert(mgr->numDelayed);
   --mgr->numDelayed;
   assert(!buf->base.base.refcount);
   pb_reference(&buf->buffer, NULL);
   FREE(buf);
}

static void _pb_cache_buffer_list_check_free

(

struct pb_cache_manager *

mgr

)

[static]

Free as many cache buffers from the list head as possible.

Definition at line 126 of file pb_bufmgr_cache.c.

References _pb_cache_buffer_destroy(), pb_cache_manager::delayed, pb_cache_buffer::end, LIST_ENTRY, list_head::next, util_time_get(), and util_time_timeout().

{
   struct list_head *curr, *next;
   struct pb_cache_buffer *buf;
   struct util_time now;
   
   util_time_get(&now);
   
   curr = mgr->delayed.next;
   next = curr->next;
   while(curr != &mgr->delayed) {
      buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);

      if(!util_time_timeout(&buf->start, &buf->end, &now))
         break;
         
      _pb_cache_buffer_destroy(buf);

      curr = next; 
      next = curr->next;
   }
}

static struct pb_cache_buffer* pb_cache_buffer

(

struct pb_buffer *

buf

)

[static, read]

Definition at line 90 of file pb_bufmgr_cache.c.

References assert.

{
   assert(buf);
   return (struct pb_cache_buffer *)buf;
}

static void pb_cache_buffer_destroy

(

struct pb_buffer *

_buf

)

[static]

Definition at line 151 of file pb_bufmgr_cache.c.

References _pb_cache_buffer_list_check_free(), assert, pb_buffer::base, pb_cache_buffer::base, pb_cache_manager::delayed, pb_cache_buffer::end, pb_cache_buffer::head, LIST_ADDTAIL, pb_cache_buffer::mgr, pb_cache_manager::mutex, pb_cache_manager::numDelayed, pb_cache_buffer(), pipe_mutex_lock, pipe_mutex_unlock, pipe_buffer::refcount, pb_cache_manager::usecs, util_time_add(), and util_time_get().

{
   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);   
   struct pb_cache_manager *mgr = buf->mgr;

   pipe_mutex_lock(mgr->mutex);
   assert(buf->base.base.refcount == 0);
   
   _pb_cache_buffer_list_check_free(mgr);
   
   util_time_get(&buf->start);
   util_time_add(&buf->start, mgr->usecs, &buf->end);
   LIST_ADDTAIL(&buf->head, &mgr->delayed);
   ++mgr->numDelayed;
   pipe_mutex_unlock(mgr->mutex);
}

static void pb_cache_buffer_get_base_buffer	(	struct pb_buffer *	_buf,
		struct pb_buffer **	base_buf,
		unsigned *	offset
	)			[static]

Definition at line 187 of file pb_bufmgr_cache.c.

References pb_cache_buffer::buffer, pb_cache_buffer(), and pb_get_base_buffer().

{
   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);
   pb_get_base_buffer(buf->buffer, base_buf, offset);
}

static void* pb_cache_buffer_map	(	struct pb_buffer *	_buf,
		unsigned	flags
	)			[static]

Definition at line 170 of file pb_bufmgr_cache.c.

References pb_cache_buffer::buffer, pb_cache_buffer(), and pb_map().

{
   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);   
   return pb_map(buf->buffer, flags);
}

static void pb_cache_buffer_unmap

(

struct pb_buffer *

_buf

)

[static]

Definition at line 179 of file pb_bufmgr_cache.c.

References pb_cache_buffer::buffer, pb_cache_buffer(), and pb_unmap().

{
   struct pb_cache_buffer *buf = pb_cache_buffer(_buf);   
   pb_unmap(buf->buffer);
}

static boolean pb_cache_is_buffer_compat	(	struct pb_cache_buffer *	buf,
		size_t	size,
		const struct pb_desc *	desc
	)			[static]

Definition at line 206 of file pb_bufmgr_cache.c.

References pipe_buffer::alignment, pb_desc::alignment, pb_buffer::base, pb_cache_buffer::base, FALSE, pb_check_alignment(), pb_check_usage(), pipe_buffer::size, TRUE, pipe_buffer::usage, and pb_desc::usage.

{
   if(buf->base.base.size < size)
      return FALSE;

   /* be lenient with size */
   if(buf->base.base.size >= 2*size)
      return FALSE;
   
   if(!pb_check_alignment(desc->alignment, buf->base.base.alignment))
      return FALSE;
   
   if(!pb_check_usage(desc->usage, buf->base.base.usage))
      return FALSE;
   
   return TRUE;
}

static struct pb_cache_manager* pb_cache_manager

(

struct pb_manager *

mgr

)

[static, read]

Definition at line 98 of file pb_bufmgr_cache.c.

References assert.

{
   assert(mgr);
   return (struct pb_cache_manager *)mgr;
}

struct pb_manager* pb_cache_manager_create	(	struct pb_manager *	provider,
		unsigned	usecs
	)			[read]

Time-based buffer cache.

This manager keeps a cache of destroyed buffers during a time interval.

Definition at line 342 of file pb_bufmgr_cache.c.

References pb_cache_manager::base, CALLOC_STRUCT, pb_manager::create_buffer, pb_cache_manager::delayed, pb_manager::destroy, pb_manager::flush, LIST_INITHEAD, pb_cache_manager::mutex, pb_cache_manager::numDelayed, pb_cache_manager_create_buffer(), pb_cache_manager_destroy(), pb_cache_manager_flush(), pipe_mutex_init, pb_cache_manager::provider, and pb_cache_manager::usecs.

{
   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;
   LIST_INITHEAD(&mgr->delayed);
   mgr->numDelayed = 0;
   pipe_mutex_init(mgr->mutex);
      
   return &mgr->base;
}

static struct pb_buffer* pb_cache_manager_create_buffer	(	struct pb_manager *	_mgr,
		size_t	size,
		const struct pb_desc *	desc
	)			[static, read]

Definition at line 228 of file pb_bufmgr_cache.c.

References _pb_cache_buffer_destroy(), pipe_buffer::alignment, pb_desc::alignment, assert, pb_buffer::base, pb_cache_buffer::base, pb_cache_buffer::buffer, CALLOC_STRUCT, pb_manager::create_buffer, pb_cache_manager::delayed, pb_cache_buffer::end, FREE, pb_cache_buffer::head, LIST_DEL, LIST_ENTRY, pb_cache_buffer::mgr, pb_cache_manager::mutex, list_head::next, pb_cache_is_buffer_compat(), pb_cache_manager(), pb_check_alignment(), pb_check_usage(), pipe_mutex_lock, pipe_mutex_unlock, pb_cache_manager::provider, pipe_buffer::refcount, pipe_buffer::size, pipe_buffer::usage, pb_desc::usage, util_time_get(), util_time_timeout(), and pb_buffer::vtbl.

{
   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;
   struct util_time now;
   
   pipe_mutex_lock(mgr->mutex);

   buf = NULL;
   curr = mgr->delayed.next;
   next = curr->next;
   
   /* search in the expired buffers, freeing them in the process */
   util_time_get(&now);
   while(curr != &mgr->delayed) {
      curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
      if(!buf && pb_cache_is_buffer_compat(curr_buf, size, desc))
         buf = curr_buf;
      else if(util_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;
      curr = next; 
      next = curr->next;
   }

   /* keep searching in the hot buffers */
   if(!buf) {
      while(curr != &mgr->delayed) {
         curr_buf = LIST_ENTRY(struct pb_cache_buffer, curr, head);
         if(pb_cache_is_buffer_compat(curr_buf, size, desc)) {
            buf = curr_buf;
            break;
         }
         /* no need to check the timeout here */
         curr = next;
         next = curr->next;
      }
   }
   
   if(buf) {
      LIST_DEL(&buf->head);
      pipe_mutex_unlock(mgr->mutex);
      ++buf->base.base.refcount;
      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);
   if(!buf->buffer) {
      FREE(buf);
      return NULL;
   }
   
   assert(buf->buffer->base.refcount >= 1);
   assert(pb_check_alignment(desc->alignment, buf->buffer->base.alignment));
   assert(pb_check_usage(desc->usage, buf->buffer->base.usage));
   assert(buf->buffer->base.size >= size);
   
   buf->base.base.refcount = 1;
   buf->base.base.alignment = buf->buffer->base.alignment;
   buf->base.base.usage = buf->buffer->base.usage;
   buf->base.base.size = buf->buffer->base.size;
   
   buf->base.vtbl = &pb_cache_buffer_vtbl;
   buf->mgr = mgr;
   
   return &buf->base;
}

static void pb_cache_manager_destroy

(

struct pb_manager *

mgr

)

[static]

Definition at line 334 of file pb_bufmgr_cache.c.

References FREE, and pb_cache_manager_flush().

{
   pb_cache_manager_flush(mgr);
   FREE(mgr);
}

static void pb_cache_manager_flush

(

struct pb_manager *

_mgr

)

[static]

Definition at line 310 of file pb_bufmgr_cache.c.

References _pb_cache_buffer_destroy(), assert, pb_cache_manager::delayed, pb_manager::flush, pb_cache_buffer::head, LIST_ENTRY, pb_cache_manager::mutex, list_head::next, pb_cache_manager(), pipe_mutex_lock, pipe_mutex_unlock, and pb_cache_manager::provider.

{
   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);
   
   assert(mgr->provider->flush);
   if(mgr->provider->flush)
      mgr->provider->flush(mgr->provider);
}

---

Variable Documentation

struct pb_vtbl pb_cache_buffer_vtbl

Initial value:

 {
      pb_cache_buffer_destroy,
      pb_cache_buffer_map,
      pb_cache_buffer_unmap,
      pb_cache_buffer_get_base_buffer
}

Definition at line 197 of file pb_bufmgr_cache.c.

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