Revert of Create libsampler as V8 sampler library. (patchset #24 id:4…

…60001 of https://codereview.chromium.org/1922303002/ )

Reason for revert:
V8 Linux64 TSAN failure because ThreadSanitizer indicated data race.

Original issue's description:
> Create libsampler as V8 sampler library.
>
> This patch does five things:
>
> 1. Extracts sampler as libsampler to provide sampling functionality support.
> 2. Makes SampleStack virtual so embedders can override the behaviour of sample collecting.
> 3. Removes sampler.[h|cc].
> 4. Moves sampling thread into log.cc as workaround to keep the --prof functionality.
> 5. Creates SamplerManager to manage the relationship between samplers and threads.
>
> The reason we port hashmap.h is that in debug mode, STL containers are using
> mutexes from a mutex pool, which may lead to deadlock when using asynchronously
> signal handler.
>
> Currently libsampler is used in V8 temporarily.
>
> BUG=v8:4789
> LOG=n
>
> Committed: https://crrev.com/06cc9b7c176a6223971deaa9fbcafe1a05058c7b
> Cr-Commit-Position: refs/heads/master@{#36527}

TBR=jochen@chromium.org,alph@chromium.org,fmeawad@chromium.org,yangguo@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4789

Review-Url: https://codereview.chromium.org/2000323007
Cr-Commit-Position: refs/heads/master@{#36529}

BUILD.gn

@@ -105,11 +105,6 @@ config("libplatform_config") {
   include_dirs = [ "include" ]
 }
 
-# This config should be applied to code using the libsampler.
-config("libsampler_config") {
-  include_dirs = [ "include" ]
-}
-
 # This config should only be applied to code using V8 and not any V8 code
 # itself.
 config("external_config") {
@@ -1334,6 +1329,8 @@ v8_source_set("v8_base") {
     "src/profiler/profile-generator-inl.h",
     "src/profiler/profile-generator.cc",
     "src/profiler/profile-generator.h",
+    "src/profiler/sampler.cc",
+    "src/profiler/sampler.h",
     "src/profiler/sampling-heap-profiler.cc",
     "src/profiler/sampling-heap-profiler.h",
     "src/profiler/strings-storage.cc",
@@ -1819,7 +1816,6 @@ v8_source_set("v8_base") {
   defines = []
   deps = [
     ":v8_libbase",
-    ":v8_libsampler",
   ]
 
   if (is_win) {
@@ -1974,23 +1970,6 @@ v8_source_set("v8_libplatform") {
   ]
 }
 
-v8_source_set("v8_libsampler") {
-  sources = [
-    "src/libsampler/hashmap.h",
-    "src/libsampler/utils.h",
-    "src/libsampler/v8-sampler.cc",
-    "src/libsampler/v8-sampler.h",
-  ]
-
-  configs = [ ":internal_config_base" ]
-
-  public_configs = [ ":libsampler_config" ]
-
-  deps = [
-    ":v8_libbase",
-  ]
-}
-
 v8_source_set("fuzzer_support") {
   visibility = [ ":*" ]  # Only targets in this file can depend on this.
 

include/v8.h

@@ -6331,12 +6331,6 @@ class V8_EXPORT Isolate {
    */
   void VisitWeakHandles(PersistentHandleVisitor* visitor);
 
-  /**
-   * Check if this isolate is in use.
-   * True if at least one thread Enter'ed this isolate.
-   */
-  bool IsInUse();
-
  private:
   template <class K, class V, class Traits>
   friend class PersistentValueMapBase;

src/api.cc

@@ -7793,12 +7793,6 @@ void Isolate::VisitExternalResources(ExternalResourceVisitor* visitor) {
 }
 
 
-bool Isolate::IsInUse() {
-  i::Isolate* isolate = reinterpret_cast<i::Isolate*>(this);
-  return isolate->IsInUse();
-}
-
-
 class VisitorAdapter : public i::ObjectVisitor {
  public:
   explicit VisitorAdapter(PersistentHandleVisitor* visitor)

src/isolate.cc

@@ -27,10 +27,10 @@
 #include "src/ic/stub-cache.h"
 #include "src/interpreter/interpreter.h"
 #include "src/isolate-inl.h"
-#include "src/libsampler/v8-sampler.h"
 #include "src/log.h"
 #include "src/messages.h"
 #include "src/profiler/cpu-profiler.h"
+#include "src/profiler/sampler.h"
 #include "src/prototype.h"
 #include "src/regexp/regexp-stack.h"
 #include "src/runtime-profiler.h"
@@ -2006,7 +2006,7 @@ void Isolate::Deinit() {
   }
 
   // We must stop the logger before we tear down other components.
-  sampler::Sampler* sampler = logger_->sampler();
+  Sampler* sampler = logger_->sampler();
   if (sampler && sampler->IsActive()) sampler->Stop();
 
   delete deoptimizer_data_;