From 133a2d1565cd37feab54e7e8b5a3b51b6256a038 Mon Sep 17 00:00:00 2001
From: Shinae Woo <shinae2012@gmail.com>
Date: Wed, 25 Jul 2018 14:23:38 -0700
Subject: [PATCH] Tread-safe track having per-worker statistics

---
 core/gate_hooks/track.cc | 17 ++++++++---------
 core/gate_hooks/track.h  | 34 ++++++++++++++++++++++++++++------
 2 files changed, 36 insertions(+), 15 deletions(-)

diff --git a/core/gate_hooks/track.cc b/core/gate_hooks/track.cc
index a8bd164e4..430fa2fb5 100644
--- a/core/gate_hooks/track.cc
+++ b/core/gate_hooks/track.cc
@@ -44,9 +44,7 @@ const GateHookCommands Track::cmds = {{"reset", "EmptyArg",
 Track::Track()
     : bess::GateHook(Track::kName, Track::kPriority),
       track_bytes_(),
-      cnt_(),
-      pkts_(),
-      bytes_() {}
+      worker_stats_() {}
 
 CommandResponse Track::Init(const bess::Gate *, const bess::pb::TrackArg &arg) {
   track_bytes_ = arg.bits();
@@ -54,23 +52,24 @@ CommandResponse Track::Init(const bess::Gate *, const bess::pb::TrackArg &arg) {
 }
 
 CommandResponse Track::CommandReset(const bess::pb::EmptyArg &) {
-  cnt_ = 0;
-  pkts_ = 0;
-  bytes_ = 0;
+  worker_stats_ = {};
   return CommandSuccess();
 }
 
 void Track::ProcessBatch(const bess::PacketBatch *batch) {
+
+  TrackStats *stat = &worker_stats_[current_worker.wid()];
+
   size_t cnt = batch->cnt();
-  cnt_ += 1;
-  pkts_ += cnt;
+  stat->cnt += 1;
+  stat->pkts += cnt;
 
   if (!track_bytes_) {
     return;
   }
 
   for (size_t i = 0; i < cnt; i++) {
-    bytes_ += batch->pkts()[i]->data_len() + kEthernetOverhead;
+    stat->bytes += batch->pkts()[i]->data_len() + kEthernetOverhead;
   }
 }
 
diff --git a/core/gate_hooks/track.h b/core/gate_hooks/track.h
index 16bab903e..5c772ed2d 100644
--- a/core/gate_hooks/track.h
+++ b/core/gate_hooks/track.h
@@ -43,11 +43,29 @@ class Track final : public bess::GateHook {
 
   CommandResponse Init(const bess::Gate *, const bess::pb::TrackArg &);
 
-  uint64_t cnt() const { return cnt_; }
+  uint64_t cnt() const {
+    uint64_t cnt = 0;
+    for (int i = 0; i < Worker::kMaxWorkers; i++) {
+      cnt += worker_stats_[i].cnt;
+    }
+    return cnt;
+  }
 
-  uint64_t pkts() const { return pkts_; }
+  uint64_t pkts() const {
+    uint64_t pkts = 0;
+    for (int i = 0; i < Worker::kMaxWorkers; i++) {
+      pkts += worker_stats_[i].pkts;
+    }
+    return pkts;
+  }
 
-  uint64_t bytes() const { return bytes_; }
+  uint64_t bytes() const {
+    uint64_t bytes = 0;
+    for (int i = 0; i < Worker::kMaxWorkers; i++) {
+      bytes += worker_stats_[i].bytes;
+    }
+    return bytes;
+  }
 
   void set_track_bytes(bool track) { track_bytes_ = track; }
 
@@ -60,9 +78,13 @@ class Track final : public bess::GateHook {
 
  private:
   bool track_bytes_;
-  uint64_t cnt_;
-  uint64_t pkts_;
-  uint64_t bytes_;
+  struct alignas(64) TrackStats {
+    uint64_t cnt;
+    uint64_t pkts;
+    uint64_t bytes;
+  };
+
+  std::array<TrackStats, Worker::kMaxWorkers> worker_stats_;
 };
 
 #endif  // BESS_GATE_HOOKS_TRACK_