[Mesa-dev] [PATCH 2/5] gallium/pb_cache: divide the cache into buckets for reducing cache misses
Marek Olšák
maraeo at gmail.com
Mon Jul 18 12:35:51 UTC 2016
From: Marek Olšák <marek.olsak at amd.com>
---
src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c | 4 +-
src/gallium/auxiliary/pipebuffer/pb_cache.c | 49 ++++++++++++++--------
src/gallium/auxiliary/pipebuffer/pb_cache.h | 12 ++++--
src/gallium/winsys/amdgpu/drm/amdgpu_bo.c | 4 +-
src/gallium/winsys/radeon/drm/radeon_drm_bo.c | 4 +-
5 files changed, 47 insertions(+), 26 deletions(-)
diff --git a/src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c b/src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c
index 4dbf3ff..250f739 100644
--- a/src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c
+++ b/src/gallium/auxiliary/pipebuffer/pb_bufmgr_cache.c
@@ -210,7 +210,7 @@ pb_cache_manager_create_buffer(struct pb_manager *_mgr,
/* get a buffer from the cache */
buf = (struct pb_cache_buffer *)
pb_cache_reclaim_buffer(&mgr->cache, size, desc->alignment,
- desc->usage);
+ desc->usage, 0);
if (buf)
return &buf->base;
@@ -243,7 +243,7 @@ pb_cache_manager_create_buffer(struct pb_manager *_mgr,
buf->base.vtbl = &pb_cache_buffer_vtbl;
buf->mgr = mgr;
- pb_cache_init_entry(&mgr->cache, &buf->cache_entry, &buf->base);
+ pb_cache_init_entry(&mgr->cache, &buf->cache_entry, &buf->base, 0);
return &buf->base;
}
diff --git a/src/gallium/auxiliary/pipebuffer/pb_cache.c b/src/gallium/auxiliary/pipebuffer/pb_cache.c
index 6a43cbc..664867b 100644
--- a/src/gallium/auxiliary/pipebuffer/pb_cache.c
+++ b/src/gallium/auxiliary/pipebuffer/pb_cache.c
@@ -53,7 +53,7 @@ destroy_buffer_locked(struct pb_cache_entry *entry)
* Free as many cache buffers from the list head as possible.
*/
static void
-release_expired_buffers_locked(struct pb_cache *mgr)
+release_expired_buffers_locked(struct list_head *cache)
{
struct list_head *curr, *next;
struct pb_cache_entry *entry;
@@ -61,9 +61,9 @@ release_expired_buffers_locked(struct pb_cache *mgr)
now = os_time_get();
- curr = mgr->cache.next;
+ curr = cache->next;
next = curr->next;
- while (curr != &mgr->cache) {
+ while (curr != cache) {
entry = LIST_ENTRY(struct pb_cache_entry, curr, head);
if (!os_time_timeout(entry->start, entry->end, now))
@@ -84,11 +84,14 @@ void
pb_cache_add_buffer(struct pb_cache_entry *entry)
{
struct pb_cache *mgr = entry->mgr;
+ struct list_head *cache = &mgr->buckets[entry->bucket_index];
+ unsigned i;
pipe_mutex_lock(mgr->mutex);
assert(!pipe_is_referenced(&entry->buffer->reference));
- release_expired_buffers_locked(mgr);
+ for (i = 0; i < ARRAY_SIZE(mgr->buckets); i++)
+ release_expired_buffers_locked(&mgr->buckets[i]);
/* Directly release any buffer that exceeds the limit. */
if (mgr->cache_size + entry->buffer->size > mgr->max_cache_size) {
@@ -99,7 +102,7 @@ pb_cache_add_buffer(struct pb_cache_entry *entry)
entry->start = os_time_get();
entry->end = entry->start + mgr->usecs;
- LIST_ADDTAIL(&entry->head, &mgr->cache);
+ LIST_ADDTAIL(&entry->head, cache);
++mgr->num_buffers;
mgr->cache_size += entry->buffer->size;
pipe_mutex_unlock(mgr->mutex);
@@ -140,23 +143,25 @@ pb_cache_is_buffer_compat(struct pb_cache_entry *entry,
*/
struct pb_buffer *
pb_cache_reclaim_buffer(struct pb_cache *mgr, pb_size size,
- unsigned alignment, unsigned usage)
+ unsigned alignment, unsigned usage,
+ unsigned bucket_index)
{
struct pb_cache_entry *entry;
struct pb_cache_entry *cur_entry;
struct list_head *cur, *next;
int64_t now;
int ret = 0;
+ struct list_head *cache = &mgr->buckets[bucket_index];
pipe_mutex_lock(mgr->mutex);
entry = NULL;
- cur = mgr->cache.next;
+ cur = cache->next;
next = cur->next;
/* search in the expired buffers, freeing them in the process */
now = os_time_get();
- while (cur != &mgr->cache) {
+ while (cur != cache) {
cur_entry = LIST_ENTRY(struct pb_cache_entry, cur, head);
if (!entry && (ret = pb_cache_is_buffer_compat(cur_entry, size,
@@ -178,7 +183,7 @@ pb_cache_reclaim_buffer(struct pb_cache *mgr, pb_size size,
/* keep searching in the hot buffers */
if (!entry && ret != -1) {
- while (cur != &mgr->cache) {
+ while (cur != cache) {
cur_entry = LIST_ENTRY(struct pb_cache_entry, cur, head);
ret = pb_cache_is_buffer_compat(cur_entry, size, alignment, usage);
@@ -219,26 +224,32 @@ pb_cache_release_all_buffers(struct pb_cache *mgr)
{
struct list_head *curr, *next;
struct pb_cache_entry *buf;
+ unsigned i;
pipe_mutex_lock(mgr->mutex);
- curr = mgr->cache.next;
- next = curr->next;
- while (curr != &mgr->cache) {
- buf = LIST_ENTRY(struct pb_cache_entry, curr, head);
- destroy_buffer_locked(buf);
- curr = next;
+ for (i = 0; i < ARRAY_SIZE(mgr->buckets); i++) {
+ struct list_head *cache = &mgr->buckets[i];
+
+ curr = cache->next;
next = curr->next;
+ while (curr != cache) {
+ buf = LIST_ENTRY(struct pb_cache_entry, curr, head);
+ destroy_buffer_locked(buf);
+ curr = next;
+ next = curr->next;
+ }
}
pipe_mutex_unlock(mgr->mutex);
}
void
pb_cache_init_entry(struct pb_cache *mgr, struct pb_cache_entry *entry,
- struct pb_buffer *buf)
+ struct pb_buffer *buf, unsigned bucket_index)
{
memset(entry, 0, sizeof(*entry));
entry->buffer = buf;
entry->mgr = mgr;
+ entry->bucket_index = bucket_index;
}
/**
@@ -262,7 +273,11 @@ pb_cache_init(struct pb_cache *mgr, uint usecs, float size_factor,
void (*destroy_buffer)(struct pb_buffer *buf),
bool (*can_reclaim)(struct pb_buffer *buf))
{
- LIST_INITHEAD(&mgr->cache);
+ unsigned i;
+
+ for (i = 0; i < ARRAY_SIZE(mgr->buckets); i++)
+ LIST_INITHEAD(&mgr->buckets[i]);
+
pipe_mutex_init(mgr->mutex);
mgr->cache_size = 0;
mgr->max_cache_size = maximum_cache_size;
diff --git a/src/gallium/auxiliary/pipebuffer/pb_cache.h b/src/gallium/auxiliary/pipebuffer/pb_cache.h
index f0fa012..aa83cc8 100644
--- a/src/gallium/auxiliary/pipebuffer/pb_cache.h
+++ b/src/gallium/auxiliary/pipebuffer/pb_cache.h
@@ -42,11 +42,16 @@ struct pb_cache_entry
struct pb_buffer *buffer; /**< Pointer to the structure this is part of. */
struct pb_cache *mgr;
int64_t start, end; /**< Caching time interval */
+ unsigned bucket_index;
};
struct pb_cache
{
- struct list_head cache;
+ /* The cache is divided into buckets for minimizing cache misses.
+ * The driver controls which buffer goes into which bucket.
+ */
+ struct list_head buckets[8];
+
pipe_mutex mutex;
uint64_t cache_size;
uint64_t max_cache_size;
@@ -61,10 +66,11 @@ struct pb_cache
void pb_cache_add_buffer(struct pb_cache_entry *entry);
struct pb_buffer *pb_cache_reclaim_buffer(struct pb_cache *mgr, pb_size size,
- unsigned alignment, unsigned usage);
+ unsigned alignment, unsigned usage,
+ unsigned bucket_index);
void pb_cache_release_all_buffers(struct pb_cache *mgr);
void pb_cache_init_entry(struct pb_cache *mgr, struct pb_cache_entry *entry,
- struct pb_buffer *buf);
+ struct pb_buffer *buf, unsigned bucket_index);
void pb_cache_init(struct pb_cache *mgr, uint usecs, float size_factor,
unsigned bypass_usage, uint64_t maximum_cache_size,
void (*destroy_buffer)(struct pb_buffer *buf),
diff --git a/src/gallium/winsys/amdgpu/drm/amdgpu_bo.c b/src/gallium/winsys/amdgpu/drm/amdgpu_bo.c
index b4dc6c7..3545b78 100644
--- a/src/gallium/winsys/amdgpu/drm/amdgpu_bo.c
+++ b/src/gallium/winsys/amdgpu/drm/amdgpu_bo.c
@@ -303,7 +303,7 @@ static struct amdgpu_winsys_bo *amdgpu_create_bo(struct amdgpu_winsys *ws,
return NULL;
}
- pb_cache_init_entry(&ws->bo_cache, &bo->cache_entry, &bo->base);
+ pb_cache_init_entry(&ws->bo_cache, &bo->cache_entry, &bo->base, 0);
request.alloc_size = size;
request.phys_alignment = alignment;
@@ -508,7 +508,7 @@ amdgpu_bo_create(struct radeon_winsys *rws,
/* Get a buffer from the cache. */
bo = (struct amdgpu_winsys_bo*)
- pb_cache_reclaim_buffer(&ws->bo_cache, size, alignment, usage);
+ pb_cache_reclaim_buffer(&ws->bo_cache, size, alignment, usage, 0);
if (bo)
return &bo->base;
diff --git a/src/gallium/winsys/radeon/drm/radeon_drm_bo.c b/src/gallium/winsys/radeon/drm/radeon_drm_bo.c
index 52b1ccd..82dec8e 100644
--- a/src/gallium/winsys/radeon/drm/radeon_drm_bo.c
+++ b/src/gallium/winsys/radeon/drm/radeon_drm_bo.c
@@ -551,7 +551,7 @@ static struct radeon_bo *radeon_create_bo(struct radeon_drm_winsys *rws,
bo->va = 0;
bo->initial_domain = initial_domains;
pipe_mutex_init(bo->map_mutex);
- pb_cache_init_entry(&rws->bo_cache, &bo->cache_entry, &bo->base);
+ pb_cache_init_entry(&rws->bo_cache, &bo->cache_entry, &bo->base, 0);
if (rws->info.has_virtual_memory) {
struct drm_radeon_gem_va va;
@@ -746,7 +746,7 @@ radeon_winsys_bo_create(struct radeon_winsys *rws,
assert(flags < sizeof(usage) * 8 - 3);
usage |= 1 << (flags + 3);
- bo = radeon_bo(pb_cache_reclaim_buffer(&ws->bo_cache, size, alignment, usage));
+ bo = radeon_bo(pb_cache_reclaim_buffer(&ws->bo_cache, size, alignment, usage, 0));
if (bo)
return &bo->base;
--
2.7.4
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