commit c4bfa6dfbb15e34171f31854c04cb8abcfdba01b
author Lionel Landwerlin <lionel.g.landwerlin@intel.com> Thu Oct 03 11:05:45 2019 +0300
committer Marge Bot <eric+marge@anholt.net> Fri Aug 07 11:27:54 2020 +0000
tree b8e586031a1ec0d7724ec77ec658add44fa9a9de
parent 63c90acc9eba2c7252794b415ad4d5ace6956c4e

intel/dump_gpu: further track mapping of BOs

We can go further in tracking what BOs are written to by the driver by
tracking when a buffer in unmapped. A BO could be mmap, written, unmap
and never be written to again. In such case we can just write the BO's
content on the first exec buf after unmap and never write it again.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2201>

src/intel/tools/intel_dump_gpu.c

diff --git a/src/intel/tools/intel_dump_gpu.c b/src/intel/tools/intel_dump_gpu.c
index 1b6a1fa..67f8559 100644
--- a/src/intel/tools/intel_dump_gpu.c
+++ b/src/intel/tools/intel_dump_gpu.c
@@ -48,9 +48,11 @@
 
 static int close_init_helper(int fd);
 static int ioctl_init_helper(int fd, unsigned long request, ...);
+static int munmap_init_helper(void *addr, size_t length);
 
 static int (*libc_close)(int fd) = close_init_helper;
 static int (*libc_ioctl)(int fd, unsigned long request, ...) = ioctl_init_helper;
+static int (*libc_munmap)(void *addr, size_t length) = munmap_init_helper;
 
 static int drm_fd = -1;
 static char *output_filename = NULL;
@@ -65,7 +67,12 @@
    uint32_t size;
    uint64_t offset;
    void *map;
-   bool mapped;
+   /* Tracks userspace mmapping of the buffer */
+   bool user_mapped : 1;
+   /* Using the i915-gem mmapping ioctl & execbuffer ioctl, track whether a
+    * buffer has been updated.
+    */
+   bool dirty : 1;
 };
 
 static struct bo *bos;
@@ -286,7 +293,7 @@
       else
          data = bo->map;
 
-      if (bo->mapped) {
+      if (bo->dirty) {
          if (bo == batch_bo) {
             aub_write_trace_block(&aub_file, AUB_TRACE_TYPE_BATCH,
                                   GET_PTR(data), bo->size, bo->offset);
@@ -294,6 +301,9 @@
             aub_write_trace_block(&aub_file, AUB_TRACE_TYPE_NOTYPE,
                                   GET_PTR(data), bo->size, bo->offset);
          }
+
+         if (!bo->user_mapped)
+            bo->dirty = false;
       }
 
       if (data != bo->map)
@@ -334,7 +344,7 @@
 
    bo->size = size;
    bo->map = map;
-   bo->mapped = false;
+   bo->user_mapped = false;
 }
 
 static void
@@ -346,7 +356,7 @@
       munmap(bo->map, bo->size);
    bo->size = 0;
    bo->map = NULL;
-   bo->mapped = false;
+   bo->user_mapped = false;
 }
 
 __attribute__ ((visibility ("default"))) int
@@ -646,7 +656,8 @@
          if (ret == 0) {
             struct drm_i915_gem_mmap *mmap = argp;
             struct bo *bo = get_bo(fd, mmap->handle);
-            bo->mapped = true;
+            bo->user_mapped = true;
+            bo->dirty = true;
          }
          return ret;
       }
@@ -664,6 +675,7 @@
 {
    libc_close = dlsym(RTLD_NEXT, "close");
    libc_ioctl = dlsym(RTLD_NEXT, "ioctl");
+   libc_munmap = dlsym(RTLD_NEXT, "munmap");
    fail_if(libc_close == NULL || libc_ioctl == NULL,
            "failed to get libc ioctl or close\n");
 }
@@ -689,6 +701,20 @@
    return libc_ioctl(fd, request, argp);
 }
 
+static int
+munmap_init_helper(void *addr, size_t length)
+{
+   init();
+   for (uint32_t i = 0; i < MAX_FD_COUNT * MAX_BO_COUNT; i++) {
+      struct bo *bo = &bos[i];
+      if (bo->map == addr) {
+         bo->user_mapped = false;
+         break;
+      }
+   }
+   return libc_munmap(addr, length);
+}
+
 static void __attribute__ ((destructor))
 fini(void)
 {