intel: Unmap buffers during drm_intel_gem_bo_unmap

We cannot afford to cache the vma per open bo as this may exhaust the
per-process limits.

References: https://bugs.freedesktop.org/show_bug.cgi?id=43075
References: https://bugs.freedesktop.org/show_bug.cgi?id=40066
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

diff --git a/intel/intel_bufmgr_gem.c b/intel/intel_bufmgr_gem.c
index 0cfeb98..d862329 100644 (file)
--- a/intel/intel_bufmgr_gem.c
+++ b/intel/intel_bufmgr_gem.c
@@ -156,6 +156,7 @@ struct _drm_intel_bo_gem {
        void *mem_virtual;
        /** GTT virtual address for the buffer, saved across map/unmap cycles */
        void *gtt_virtual;
+       int map_count;
 
        /** BO cache list */
        drmMMListHead head;
@@ -879,11 +880,6 @@ drm_intel_gem_bo_free(drm_intel_bo *bo)
        struct drm_gem_close close;
        int ret;
 
-       if (bo_gem->mem_virtual)
-               munmap(bo_gem->mem_virtual, bo_gem->bo.size);
-       if (bo_gem->gtt_virtual)
-               munmap(bo_gem->gtt_virtual, bo_gem->bo.size);
-
        /* Close this object */
        memset(&close, 0, sizeof(close));
        close.handle = bo_gem->gem_handle;
@@ -1017,6 +1013,7 @@ static int drm_intel_gem_bo_map(drm_intel_bo *bo, int write_enable)
                struct drm_i915_gem_mmap mmap_arg;
 
                DBG("bo_map: %d (%s)\n", bo_gem->gem_handle, bo_gem->name);
+               assert(bo_gem->map_count == 0);
 
                memset(&mmap_arg, 0, sizeof(mmap_arg));
                mmap_arg.handle = bo_gem->gem_handle;
@@ -1038,6 +1035,7 @@ static int drm_intel_gem_bo_map(drm_intel_bo *bo, int write_enable)
        DBG("bo_map: %d (%s) -> %p\n", bo_gem->gem_handle, bo_gem->name,
            bo_gem->mem_virtual);
        bo->virtual = bo_gem->mem_virtual;
+       bo_gem->map_count++;
 
        set_domain.handle = bo_gem->gem_handle;
        set_domain.read_domains = I915_GEM_DOMAIN_CPU;
@@ -1077,6 +1075,7 @@ int drm_intel_gem_bo_map_gtt(drm_intel_bo *bo)
 
                DBG("bo_map_gtt: mmap %d (%s)\n", bo_gem->gem_handle,
                    bo_gem->name);
+               assert(bo_gem->map_count == 0);
 
                memset(&mmap_arg, 0, sizeof(mmap_arg));
                mmap_arg.handle = bo_gem->gem_handle;
@@ -1112,6 +1111,7 @@ int drm_intel_gem_bo_map_gtt(drm_intel_bo *bo)
        }
 
        bo->virtual = bo_gem->gtt_virtual;
+       bo_gem->map_count++;
 
        DBG("bo_map_gtt: %d (%s) -> %p\n", bo_gem->gem_handle, bo_gem->name,
            bo_gem->gtt_virtual);
@@ -1161,7 +1161,22 @@ static int drm_intel_gem_bo_unmap(drm_intel_bo *bo)
                bo_gem->mapped_cpu_write = false;
        }
 
-       bo->virtual = NULL;
+       /* We need to unmap after every innovation as we cannot track
+        * an open vma for every bo as that will exhaasut the system
+        * limits and cause later failures.
+        */
+       if (--bo_gem->map_count == 0) {
+               if (bo_gem->mem_virtual) {
+                       munmap(bo_gem->mem_virtual, bo_gem->bo.size);
+                       bo_gem->mem_virtual = NULL;
+               }
+               if (bo_gem->gtt_virtual) {
+                       munmap(bo_gem->gtt_virtual, bo_gem->bo.size);
+                       bo_gem->gtt_virtual = NULL;
+               }
+
+               bo->virtual = NULL;
+       }
        pthread_mutex_unlock(&bufmgr_gem->lock);
 
        return ret;