From f00b54bc9e70e49f546ac2efeceb59540ff4a6fd Mon Sep 17 00:00:00 2001
From: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Date: Fri, 8 Oct 2021 02:11:19 +0200
Subject: [PATCH] radv: Rework modification detection of the meta cache.

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/19047>
---
 src/amd/vulkan/radv_meta.c           | 9 +++++++--
 src/amd/vulkan/radv_pipeline_cache.c | 2 --
 src/amd/vulkan/radv_private.h        | 2 +-
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/src/amd/vulkan/radv_meta.c b/src/amd/vulkan/radv_meta.c
index ea55b31aa89..7db1fbdd0cc 100644
--- a/src/amd/vulkan/radv_meta.c
+++ b/src/amd/vulkan/radv_meta.c
@@ -322,7 +322,8 @@ radv_load_meta_pipeline(struct radv_device *device)
 fail:
    result = radv_CreatePipelineCache(radv_device_to_handle(device), &create_info, NULL, &device->meta_state.cache);
    if (result == VK_SUCCESS) {
-      ret = radv_pipeline_cache_from_handle(device->meta_state.cache)->kernel_count > 0;
+      device->meta_state.initial_cache_entries = radv_pipeline_cache_from_handle(device->meta_state.cache)->kernel_count;
+      ret = device->meta_state.initial_cache_entries > 0;
    }
 
    free(data);
@@ -340,7 +341,11 @@ radv_store_meta_pipeline(struct radv_device *device)
    size_t size;
    void *data = NULL;
 
-   if (!radv_pipeline_cache_from_handle(device->meta_state.cache)->modified)
+   if (device->meta_state.cache == VK_NULL_HANDLE)
+      return;
+
+   /* Skip serialization if no entries were added. */
+   if (radv_pipeline_cache_from_handle(device->meta_state.cache)->kernel_count <= device->meta_state.initial_cache_entries)
       return;
 
    if (radv_GetPipelineCacheData(radv_device_to_handle(device),
diff --git a/src/amd/vulkan/radv_pipeline_cache.c b/src/amd/vulkan/radv_pipeline_cache.c
index 9e0e445a6a0..06b825b98b6 100644
--- a/src/amd/vulkan/radv_pipeline_cache.c
+++ b/src/amd/vulkan/radv_pipeline_cache.c
@@ -82,7 +82,6 @@ radv_pipeline_cache_init(struct radv_pipeline_cache *cache, struct radv_device *
    mtx_init(&cache->mutex, mtx_plain);
    cache->flags = 0;
 
-   cache->modified = false;
    cache->kernel_count = 0;
    cache->total_size = 0;
    cache->table_size = 1024;
@@ -571,7 +570,6 @@ radv_pipeline_cache_insert_shaders(struct radv_device *device, struct radv_pipel
 
    radv_pipeline_cache_add_entry(cache, entry);
 
-   cache->modified = true;
    radv_pipeline_cache_unlock(cache);
    return;
 }
diff --git a/src/amd/vulkan/radv_private.h b/src/amd/vulkan/radv_private.h
index 7aaace60fa6..880e33fd322 100644
--- a/src/amd/vulkan/radv_private.h
+++ b/src/amd/vulkan/radv_private.h
@@ -377,7 +377,6 @@ struct radv_pipeline_cache {
    uint32_t table_size;
    uint32_t kernel_count;
    struct cache_entry **hash_table;
-   bool modified;
 
    VkAllocationCallbacks alloc;
 };
@@ -442,6 +441,7 @@ struct radv_meta_state {
    VkAllocationCallbacks alloc;
 
    VkPipelineCache cache;
+   uint32_t initial_cache_entries;
 
    /*
     * For on-demand pipeline creation, makes sure that