[Mesa-dev] [PATCH] radv: Fix pipeline cache locking issues

[Alex Smith]

Need to lock around the whole process of retrieving cached shaders, and
around GetPipelineCacheData.

This fixes GPU hangs observed when creating multiple pipelines in
parallel, which appeared to be due to invalid shader code being pulled
from the cache.

Signed-off-by: Alex Smith <asmith at feralinteractive.com>
---
 src/amd/vulkan/radv_pipeline_cache.c | 30 +++++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 7 deletions(-)

diff --git a/src/amd/vulkan/radv_pipeline_cache.c b/src/amd/vulkan/radv_pipeline_cache.c
index 034dc35af8..a75356b822 100644
--- a/src/amd/vulkan/radv_pipeline_cache.c
+++ b/src/amd/vulkan/radv_pipeline_cache.c
@@ -177,15 +177,20 @@ radv_create_shader_variants_from_pipeline_cache(struct radv_device *device,
 					        struct radv_shader_variant **variants)
 {
 	struct cache_entry *entry;
-	if (cache)
-		entry = radv_pipeline_cache_search(cache, sha1);
-	else
-		entry = radv_pipeline_cache_search(device->mem_cache, sha1);
+
+	if (!cache)
+		cache = device->mem_cache;
+
+	pthread_mutex_lock(&cache->mutex);
+
+	entry = radv_pipeline_cache_search_unlocked(cache, sha1);
 
 	if (!entry) {
 		if (!device->physical_device->disk_cache ||
-		    (device->instance->debug_flags & RADV_DEBUG_NO_CACHE))
+		    (device->instance->debug_flags & RADV_DEBUG_NO_CACHE)) {
+			pthread_mutex_unlock(&cache->mutex);
 			return false;
+		}
 
 		uint8_t disk_sha1[20];
 		disk_cache_compute_key(device->physical_device->disk_cache,
@@ -193,8 +198,10 @@ radv_create_shader_variants_from_pipeline_cache(struct radv_device *device,
 		entry = (struct cache_entry *)
 			disk_cache_get(device->physical_device->disk_cache,
 				       disk_sha1, NULL);
-		if (!entry)
+		if (!entry) {
+			pthread_mutex_unlock(&cache->mutex);
 			return false;
+		}
 	}
 
 	char *p = entry->code;
@@ -204,8 +211,10 @@ radv_create_shader_variants_from_pipeline_cache(struct radv_device *device,
 			struct cache_entry_variant_info info;
 
 			variant = calloc(1, sizeof(struct radv_shader_variant));
-			if (!variant)
+			if (!variant) {
+				pthread_mutex_unlock(&cache->mutex);
 				return false;
+			}
 
 			memcpy(&info, p, sizeof(struct cache_entry_variant_info));
 			p += sizeof(struct cache_entry_variant_info);
@@ -231,6 +240,7 @@ radv_create_shader_variants_from_pipeline_cache(struct radv_device *device,
 			p_atomic_inc(&entry->variants[i]->ref_count);
 
 	memcpy(variants, entry->variants, sizeof(entry->variants));
+	pthread_mutex_unlock(&cache->mutex);
 	return true;
 }
 
@@ -509,12 +519,17 @@ VkResult radv_GetPipelineCacheData(
 	RADV_FROM_HANDLE(radv_pipeline_cache, cache, _cache);
 	struct cache_header *header;
 	VkResult result = VK_SUCCESS;
+
+	pthread_mutex_lock(&cache->mutex);
+
 	const size_t size = sizeof(*header) + cache->total_size;
 	if (pData == NULL) {
+		pthread_mutex_unlock(&cache->mutex);
 		*pDataSize = size;
 		return VK_SUCCESS;
 	}
 	if (*pDataSize < sizeof(*header)) {
+		pthread_mutex_unlock(&cache->mutex);
 		*pDataSize = 0;
 		return VK_INCOMPLETE;
 	}
@@ -545,6 +560,7 @@ VkResult radv_GetPipelineCacheData(
 	}
 	*pDataSize = p - pData;
 
+	pthread_mutex_unlock(&cache->mutex);
 	return result;
 }
 
-- 
2.13.6