[Intel-gfx] [PATCH libdrm 2/2] intel: Migrate handle/name lookups from linear lists to hashtables

Chris Wilson chris at chris-wilson.co.uk
Thu Sep 22 14:05:15 UTC 2016


Walking a linear list to find a matching PRIME handle or flinked name
does not scale and becomes a major burden with just a few objects.

References: https://bugs.freedesktop.org/show_bug.cgi?id=94631
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 intel/intel_bufmgr_gem.c | 127 +++++++++++++++++++++++++++--------------------
 xf86drm.h                |   1 +
 xf86drmHash.c            |  11 ++++
 3 files changed, 85 insertions(+), 54 deletions(-)

diff --git a/intel/intel_bufmgr_gem.c b/intel/intel_bufmgr_gem.c
index 0f212e9..6c9276c 100644
--- a/intel/intel_bufmgr_gem.c
+++ b/intel/intel_bufmgr_gem.c
@@ -39,6 +39,7 @@
 #endif
 
 #include <xf86drm.h>
+#include <xf86drmHash.h>
 #include <xf86atomic.h>
 #include <fcntl.h>
 #include <stdio.h>
@@ -130,7 +131,9 @@ typedef struct _drm_intel_bufmgr_gem {
 
 	drmMMListHead managers;
 
-	drmMMListHead named;
+	HashTable *name_table;
+	HashTable *handle_table;
+
 	drmMMListHead vma_cache;
 	int vma_count, vma_open, vma_max;
 
@@ -175,7 +178,6 @@ struct _drm_intel_bo_gem {
          * List contains both flink named and prime fd'd objects
 	 */
 	unsigned int global_name;
-	drmMMListHead name_list;
 
 	/**
 	 * Index of the buffer within the validation list while preparing a
@@ -808,6 +810,10 @@ retry:
 		if (!bo_gem)
 			return NULL;
 
+		/* drm_intel_gem_bo_free calls DRMLISTDEL() for an uninitialized
+		   list (vma_list), so better set the list head here */
+		DRMINITLISTHEAD(&bo_gem->vma_list);
+
 		bo_gem->bo.size = bo_size;
 
 		memclear(create);
@@ -816,23 +822,26 @@ retry:
 		ret = drmIoctl(bufmgr_gem->fd,
 			       DRM_IOCTL_I915_GEM_CREATE,
 			       &create);
-		bo_gem->gem_handle = create.handle;
-		bo_gem->bo.handle = bo_gem->gem_handle;
 		if (ret != 0) {
 			free(bo_gem);
 			return NULL;
 		}
+
+		bo_gem->gem_handle = create.handle;
+		bo_gem->bo.handle = bo_gem->gem_handle;
 		bo_gem->bo.bufmgr = bufmgr;
 		bo_gem->bo.align = alignment;
 
+		if (drmHashInsert(bufmgr_gem->handle_table,
+				  bo_gem->gem_handle, bo_gem)) {
+			drm_intel_gem_bo_free(&bo_gem->bo);
+			return NULL;
+		}
+
 		bo_gem->tiling_mode = I915_TILING_NONE;
 		bo_gem->swizzle_mode = I915_BIT_6_SWIZZLE_NONE;
 		bo_gem->stride = 0;
 
-		/* drm_intel_gem_bo_free calls DRMLISTDEL() for an uninitialized
-		   list (vma_list), so better set the list head here */
-		DRMINITLISTHEAD(&bo_gem->name_list);
-		DRMINITLISTHEAD(&bo_gem->vma_list);
 		if (drm_intel_gem_bo_set_tiling_internal(&bo_gem->bo,
 							 tiling_mode,
 							 stride)) {
@@ -956,6 +965,8 @@ drm_intel_gem_bo_alloc_userptr(drm_intel_bufmgr *bufmgr,
 	if (!bo_gem)
 		return NULL;
 
+	DRMINITLISTHEAD(&bo_gem->vma_list);
+
 	bo_gem->bo.size = size;
 
 	memclear(userptr);
@@ -985,8 +996,11 @@ drm_intel_gem_bo_alloc_userptr(drm_intel_bufmgr *bufmgr,
 	bo_gem->swizzle_mode = I915_BIT_6_SWIZZLE_NONE;
 	bo_gem->stride       = 0;
 
-	DRMINITLISTHEAD(&bo_gem->name_list);
-	DRMINITLISTHEAD(&bo_gem->vma_list);
+	if (drmHashInsert(bufmgr_gem->handle_table,
+			  bo_gem->gem_handle, bo_gem)) {
+		drm_intel_gem_bo_free(&bo_gem->bo);
+		return NULL;
+	}
 
 	bo_gem->name = name;
 	atomic_set(&bo_gem->refcount, 1);
@@ -1087,7 +1101,6 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
 	int ret;
 	struct drm_gem_open open_arg;
 	struct drm_i915_gem_get_tiling get_tiling;
-	drmMMListHead *list;
 
 	/* At the moment most applications only have a few named bo.
 	 * For instance, in a DRI client only the render buffers passed
@@ -1096,15 +1109,11 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
 	 * provides a sufficiently fast match.
 	 */
 	pthread_mutex_lock(&bufmgr_gem->lock);
-	for (list = bufmgr_gem->named.next;
-	     list != &bufmgr_gem->named;
-	     list = list->next) {
-		bo_gem = DRMLISTENTRY(drm_intel_bo_gem, list, name_list);
-		if (bo_gem->global_name == handle) {
-			drm_intel_gem_bo_reference(&bo_gem->bo);
-			pthread_mutex_unlock(&bufmgr_gem->lock);
-			return &bo_gem->bo;
-		}
+	bo_gem = drmHashLookupValue(bufmgr_gem->name_table, handle);
+	if (bo_gem) {
+		drm_intel_gem_bo_reference(&bo_gem->bo);
+		pthread_mutex_unlock(&bufmgr_gem->lock);
+		return &bo_gem->bo;
 	}
 
 	memclear(open_arg);
@@ -1122,15 +1131,11 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
          * object from the kernel before by looking through the list
          * again for a matching gem_handle
          */
-	for (list = bufmgr_gem->named.next;
-	     list != &bufmgr_gem->named;
-	     list = list->next) {
-		bo_gem = DRMLISTENTRY(drm_intel_bo_gem, list, name_list);
-		if (bo_gem->gem_handle == open_arg.handle) {
-			drm_intel_gem_bo_reference(&bo_gem->bo);
-			pthread_mutex_unlock(&bufmgr_gem->lock);
-			return &bo_gem->bo;
-		}
+	bo_gem = drmHashLookupValue(bufmgr_gem->handle_table, open_arg.handle);
+	if (bo_gem) {
+		drm_intel_gem_bo_reference(&bo_gem->bo);
+		pthread_mutex_unlock(&bufmgr_gem->lock);
+		return &bo_gem->bo;
 	}
 
 	bo_gem = calloc(1, sizeof(*bo_gem));
@@ -1139,6 +1144,8 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
 		return NULL;
 	}
 
+	DRMINITLISTHEAD(&bo_gem->vma_list);
+
 	bo_gem->bo.size = open_arg.size;
 	bo_gem->bo.offset = 0;
 	bo_gem->bo.offset64 = 0;
@@ -1153,14 +1160,23 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
 	bo_gem->reusable = false;
 	bo_gem->use_48b_address_range = false;
 
+	if (drmHashInsert(bufmgr_gem->handle_table,
+			  bo_gem->gem_handle, bo_gem) ||
+	    drmHashInsert(bufmgr_gem->name_table,
+			  bo_gem->global_name, bo_gem)) {
+		pthread_mutex_unlock(&bufmgr_gem->lock);
+		drm_intel_gem_bo_unreference(&bo_gem->bo);
+		return NULL;
+	}
+
 	memclear(get_tiling);
 	get_tiling.handle = bo_gem->gem_handle;
 	ret = drmIoctl(bufmgr_gem->fd,
 		       DRM_IOCTL_I915_GEM_GET_TILING,
 		       &get_tiling);
 	if (ret != 0) {
-		drm_intel_gem_bo_unreference(&bo_gem->bo);
 		pthread_mutex_unlock(&bufmgr_gem->lock);
+		drm_intel_gem_bo_unreference(&bo_gem->bo);
 		return NULL;
 	}
 	bo_gem->tiling_mode = get_tiling.tiling_mode;
@@ -1168,8 +1184,6 @@ drm_intel_bo_gem_create_from_name(drm_intel_bufmgr *bufmgr,
 	/* XXX stride is unknown */
 	drm_intel_bo_gem_set_in_aperture_size(bufmgr_gem, bo_gem, 0);
 
-	DRMINITLISTHEAD(&bo_gem->vma_list);
-	DRMLISTADDTAIL(&bo_gem->name_list, &bufmgr_gem->named);
 	pthread_mutex_unlock(&bufmgr_gem->lock);
 	DBG("bo_create_from_handle: %d (%s)\n", handle, bo_gem->name);
 
@@ -1200,6 +1214,8 @@ drm_intel_gem_bo_free(drm_intel_bo *bo)
 		bufmgr_gem->vma_count--;
 	}
 
+	drmHashDelete(bufmgr_gem->handle_table, bo_gem->gem_handle);
+
 	/* Close this object */
 	memclear(close);
 	close.handle = bo_gem->gem_handle;
@@ -1377,7 +1393,8 @@ drm_intel_gem_bo_unreference_final(drm_intel_bo *bo, time_t time)
 		drm_intel_gem_bo_mark_mmaps_incoherent(bo);
 	}
 
-	DRMLISTDEL(&bo_gem->name_list);
+	if (bo_gem->global_name)
+		drmHashDelete(bufmgr_gem->name_table, bo_gem->global_name);
 
 	bucket = drm_intel_gem_bo_bucket_for_size(bufmgr_gem, bo->size);
 	/* Put the buffer into our internal cache for reuse if we can. */
@@ -2610,7 +2627,6 @@ drm_intel_bo_gem_create_from_prime(drm_intel_bufmgr *bufmgr, int prime_fd, int s
 	uint32_t handle;
 	drm_intel_bo_gem *bo_gem;
 	struct drm_i915_gem_get_tiling get_tiling;
-	drmMMListHead *list;
 
 	pthread_mutex_lock(&bufmgr_gem->lock);
 	ret = drmPrimeFDToHandle(bufmgr_gem->fd, prime_fd, &handle);
@@ -2625,15 +2641,11 @@ drm_intel_bo_gem_create_from_prime(drm_intel_bufmgr *bufmgr, int prime_fd, int s
 	 * for named buffers, we must not create two bo's pointing at the same
 	 * kernel object
 	 */
-	for (list = bufmgr_gem->named.next;
-	     list != &bufmgr_gem->named;
-	     list = list->next) {
-		bo_gem = DRMLISTENTRY(drm_intel_bo_gem, list, name_list);
-		if (bo_gem->gem_handle == handle) {
-			drm_intel_gem_bo_reference(&bo_gem->bo);
-			pthread_mutex_unlock(&bufmgr_gem->lock);
-			return &bo_gem->bo;
-		}
+	bo_gem = drmHashLookupValue(bufmgr_gem->name_table, handle);
+	if (bo_gem) {
+		drm_intel_gem_bo_reference(&bo_gem->bo);
+		pthread_mutex_unlock(&bufmgr_gem->lock);
+		return &bo_gem->bo;
 	}
 
 	bo_gem = calloc(1, sizeof(*bo_gem));
@@ -2641,6 +2653,9 @@ drm_intel_bo_gem_create_from_prime(drm_intel_bufmgr *bufmgr, int prime_fd, int s
 		pthread_mutex_unlock(&bufmgr_gem->lock);
 		return NULL;
 	}
+
+	DRMINITLISTHEAD(&bo_gem->vma_list);
+
 	/* Determine size of bo.  The fd-to-handle ioctl really should
 	 * return the size, but it doesn't.  If we have kernel 3.12 or
 	 * later, we can lseek on the prime fd to get the size.  Older
@@ -2656,6 +2671,12 @@ drm_intel_bo_gem_create_from_prime(drm_intel_bufmgr *bufmgr, int prime_fd, int s
 	bo_gem->bo.bufmgr = bufmgr;
 
 	bo_gem->gem_handle = handle;
+	if (drmHashInsert(bufmgr_gem->handle_table,
+			  bo_gem->gem_handle, bo_gem)) {
+		drm_intel_gem_bo_free(&bo_gem->bo);
+		pthread_mutex_unlock(&bufmgr_gem->lock);
+		return NULL;
+	}
 
 	atomic_set(&bo_gem->refcount, 1);
 
@@ -2667,8 +2688,6 @@ drm_intel_bo_gem_create_from_prime(drm_intel_bufmgr *bufmgr, int prime_fd, int s
 	bo_gem->reusable = false;
 	bo_gem->use_48b_address_range = false;
 
-	DRMINITLISTHEAD(&bo_gem->vma_list);
-	DRMLISTADDTAIL(&bo_gem->name_list, &bufmgr_gem->named);
 	pthread_mutex_unlock(&bufmgr_gem->lock);
 
 	memclear(get_tiling);
@@ -2695,11 +2714,6 @@ drm_intel_bo_gem_export_to_prime(drm_intel_bo *bo, int *prime_fd)
 	drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *) bo->bufmgr;
 	drm_intel_bo_gem *bo_gem = (drm_intel_bo_gem *) bo;
 
-	pthread_mutex_lock(&bufmgr_gem->lock);
-        if (DRMLISTEMPTY(&bo_gem->name_list))
-                DRMLISTADDTAIL(&bo_gem->name_list, &bufmgr_gem->named);
-	pthread_mutex_unlock(&bufmgr_gem->lock);
-
 	if (drmPrimeHandleToFD(bufmgr_gem->fd, bo_gem->gem_handle,
 			       DRM_CLOEXEC, prime_fd) != 0)
 		return -errno;
@@ -2725,16 +2739,20 @@ drm_intel_gem_bo_flink(drm_intel_bo *bo, uint32_t * name)
 		pthread_mutex_lock(&bufmgr_gem->lock);
 
 		ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_GEM_FLINK, &flink);
-		if (ret != 0) {
+		if (ret) {
 			pthread_mutex_unlock(&bufmgr_gem->lock);
 			return -errno;
 		}
 
+		if (drmHashInsert(bufmgr_gem->name_table,
+				  bo_gem->global_name, bo_gem)) {
+			pthread_mutex_unlock(&bufmgr_gem->lock);
+			return -ENOMEM;
+		}
+
 		bo_gem->global_name = flink.name;
 		bo_gem->reusable = false;
 
-                if (DRMLISTEMPTY(&bo_gem->name_list))
-                        DRMLISTADDTAIL(&bo_gem->name_list, &bufmgr_gem->named);
 		pthread_mutex_unlock(&bufmgr_gem->lock);
 	}
 
@@ -3691,7 +3709,8 @@ drm_intel_bufmgr_gem_init(int fd, int batch_size)
 	    drm_intel_gem_get_pipe_from_crtc_id;
 	bufmgr_gem->bufmgr.bo_references = drm_intel_gem_bo_references;
 
-	DRMINITLISTHEAD(&bufmgr_gem->named);
+	bufmgr_gem->name_table = drmHashCreate();
+	bufmgr_gem->handle_table = drmHashCreate();
 	init_cache_buckets(bufmgr_gem);
 
 	DRMINITLISTHEAD(&bufmgr_gem->vma_cache);
diff --git a/xf86drm.h b/xf86drm.h
index 481d882..df1885e 100644
--- a/xf86drm.h
+++ b/xf86drm.h
@@ -695,6 +695,7 @@ extern void          drmFree(void *pt);
 extern void *drmHashCreate(void);
 extern int  drmHashDestroy(void *t);
 extern int  drmHashLookup(void *t, unsigned long key, void **value);
+extern void *drmHashLookupValue(void *t, unsigned long key);
 extern int  drmHashInsert(void *t, unsigned long key, void *value);
 extern int  drmHashDelete(void *t, unsigned long key);
 extern int  drmHashFirst(void *t, unsigned long *key, void **value);
diff --git a/xf86drmHash.c b/xf86drmHash.c
index f287e61..f689240 100644
--- a/xf86drmHash.c
+++ b/xf86drmHash.c
@@ -185,6 +185,17 @@ int drmHashLookup(void *t, unsigned long key, void **value)
     return 0;			/* Found */
 }
 
+void *drmHashLookupValue(void *t, unsigned long key)
+{
+    HashBucketPtr bucket;
+
+    bucket = HashFind(t, key, NULL);
+    if (!bucket)
+	    return NULL;
+
+    return bucket->value;
+}
+
 int drmHashInsert(void *t, unsigned long key, void *value)
 {
     HashTablePtr  table = (HashTablePtr)t;
-- 
2.9.3



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