Adding 'isolates' argument to LOG to get rid of multiple TLS fetches in profiling.

src/platform-linux.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 239 matching lines @@
 
 
 void* OS::Allocate(const size_t requested,
                    size_t* allocated,
                    bool is_executable) {
   // TODO(805): Port randomization of allocated executable memory to Linux.
   const size_t msize = RoundUp(requested, sysconf(_SC_PAGESIZE));
   int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
   void* mbase = mmap(NULL, msize, prot, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   if (mbase == MAP_FAILED) {
-    LOG(StringEvent("OS::Allocate", "mmap failed"));
+    LOG(i::Isolate::Current(),
+        StringEvent("OS::Allocate", "mmap failed"));
     return NULL;
   }
   *allocated = msize;
   UpdateAllocatedSpaceLimits(mbase, msize);
   return mbase;
 }
 
 
 void OS::Free(void* address, const size_t size) {
   // TODO(1240712): munmap has a return value which is ignored here.
@@ skipping 100 matching lines @@
   // This function assumes that the layout of the file is as follows:
   // hex_start_addr-hex_end_addr rwxp <unused data> [binary_file_name]
   // If we encounter an unexpected situation we abort scanning further entries.
   FILE* fp = fopen("/proc/self/maps", "r");
   if (fp == NULL) return;
 
   // Allocate enough room to be able to store a full file name.
   const int kLibNameLen = FILENAME_MAX + 1;
   char* lib_name = reinterpret_cast<char*>(malloc(kLibNameLen));
 
+  i::Isolate* isolate = ISOLATE;
   // This loop will terminate once the scanning hits an EOF.
   while (true) {
     uintptr_t start, end;
     char attr_r, attr_w, attr_x, attr_p;
     // Parse the addresses and permission bits at the beginning of the line.
     if (fscanf(fp, "%" V8PRIxPTR "-%" V8PRIxPTR, &start, &end) != 2) break;
     if (fscanf(fp, " %c%c%c%c", &attr_r, &attr_w, &attr_x, &attr_p) != 4) break;
 
     int c;
     if (attr_r == 'r' && attr_w != 'w' && attr_x == 'x') {
@@ skipping 13 matching lines @@
 
         // Drop the newline character read by fgets. We do not need to check
         // for a zero-length string because we know that we at least read the
         // '/' character.
         lib_name[strlen(lib_name) - 1] = '\0';
       } else {
         // No library name found, just record the raw address range.
         snprintf(lib_name, kLibNameLen,
                  "%08" V8PRIxPTR "-%08" V8PRIxPTR, start, end);
       }
-      LOG(SharedLibraryEvent(lib_name, start, end));
+      LOG(isolate, SharedLibraryEvent(lib_name, start, end));
     } else {
       // Entry not describing executable data. Skip to end of line to setup
       // reading the next entry.
       do {
         c = getc(fp);
       } while ((c != EOF) && (c != '\n'));
       if (c == EOF) break;
     }
   }
   free(lib_name);
@@ skipping 606 matching lines @@
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SignalSender::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal