cros: Add UMA stat for graphics driver memory on tab discard

base/process_util_linux.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/process_util.h"
 
 #include <dirent.h>
 #include <malloc.h>
 #include <sys/time.h>
 #include <sys/types.h>
@@ skipping 605 matching lines @@
 
 SystemMemoryInfoKB::SystemMemoryInfoKB()
     : total(0),
       free(0),
       buffers(0),
       cached(0),
       active_anon(0),
       inactive_anon(0),
       active_file(0),
       inactive_file(0),
-      shmem(0) {
+      shmem(0),
+      gem_objects(-1),
+      gem_size(-1) {
 }
 
 bool GetSystemMemoryInfo(SystemMemoryInfoKB* meminfo) {
   // Synchronously reading files in /proc is safe.
   base::ThreadRestrictions::ScopedAllowIO allow_io;
 
   // Used memory is: total - free - buffers - caches
   FilePath meminfo_file("/proc/meminfo");
   std::string meminfo_data;
   if (!file_util::ReadFileToString(meminfo_file, &meminfo_data)) {
@@ skipping 34 matching lines @@
   // meminfo format varies on different hardware so we have to search for the
   // string.  It always appears after "Cached:".
   for (size_t i = kMemCachedIndex+2; i < meminfo_fields.size(); i += 3) {
     if (meminfo_fields[i] == "Shmem:") {
       base::StringToInt(meminfo_fields[i+1], &meminfo->shmem);
       break;
     }
   }
 #endif
 
-  // Check for gem data and report if present.
+  // Check for graphics memory data and report if present. Synchronously
+  // reading files in /sys is fast.
+#if defined(ARCH_CPU_ARM_FAMILY)
+  FilePath geminfo_file("/sys/kernel/debug/dri/0/exynos_gem_objects");
+#else
   FilePath geminfo_file("/sys/kernel/debug/dri/0/i915_gem_objects");
+#endif
   std::string geminfo_data;
-  FilePath mali_memory_file("/sys/devices/platform/mali.0/memory");
-  std::string mali_memory_data;
   meminfo->gem_objects = -1;
   meminfo->gem_size = -1;
   if (file_util::ReadFileToString(geminfo_file, &geminfo_data)) {
     int gem_objects = -1;
     long long gem_size = -1;
     int num_res = sscanf(geminfo_data.c_str(),
                          "%d objects, %lld bytes",
                          &gem_objects, &gem_size);
     if (num_res == 2) {
       meminfo->gem_objects = gem_objects;
       meminfo->gem_size = gem_size;
     }
-  } else {
-    if (file_util::ReadFileToString(mali_memory_file, &mali_memory_data)) {
-      long long mali_size = -1;
-      int num_res = sscanf(mali_memory_data.c_str(), "%lld bytes", &mali_size);
-      if (num_res == 1)
-        meminfo->gem_size = mali_size;
-    }
+  }
 
+#if defined(ARCH_CPU_ARM_FAMILY)
+  // Incorporate Mali graphics memory if present.
+  FilePath mali_memory_file("/sys/devices/platform/mali.0/memory");
+  std::string mali_memory_data;
+  if (file_util::ReadFileToString(mali_memory_file, &mali_memory_data)) {
+    long long mali_size = -1;
+    int num_res = sscanf(mali_memory_data.c_str(), "%lld bytes", &mali_size);
+    if (num_res == 1)
+      meminfo->gem_size += mali_size;
   }
+#endif  // defined(ARCH_CPU_ARM_FAMILY)
+
   return true;
 }
 
 size_t GetSystemCommitCharge() {
   SystemMemoryInfoKB meminfo;
   if (!GetSystemMemoryInfo(&meminfo))
     return 0;
   return meminfo.total - meminfo.free - meminfo.buffers - meminfo.cached;
 }
 
@@ skipping 150 matching lines @@
     int score_len = static_cast<int>(score_str.length());
     return (score_len == file_util::WriteFile(oom_file,
                                               score_str.c_str(),
                                               score_len));
   }
 
   return false;
 }
 
 }  // namespace base