(trafficserver) branch ETVolatile created (now 974daa7cc1)

[wk...@apache.org]

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wkaras pushed a change to branch ETVolatile
in repository https://gitbox.apache.org/repos/asf/trafficserver.git


      at 974daa7cc1 Change volatile to atomic in EThread.h.

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     new 974daa7cc1 Change volatile to atomic in EThread.h.

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(trafficserver) 01/01: Change volatile to atomic in EThread.h.

[wk...@apache.org]

This is an automated email from the ASF dual-hosted git repository.

wkaras pushed a commit to branch ETVolatile
in repository https://gitbox.apache.org/repos/asf/trafficserver.git

commit 974daa7cc1e6eee66b4bd55b98c775ea9d1a064c
Author: Walt Karas <wk...@yahooinc.com>
AuthorDate: Tue Dec 12 17:15:53 2023 +0000

    Change volatile to atomic in EThread.h.
---
 include/iocore/eventsystem/EThread.h  | 6 ++++--
 src/iocore/eventsystem/UnixEThread.cc | 8 ++++----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/include/iocore/eventsystem/EThread.h b/include/iocore/eventsystem/EThread.h
index 8f7e069773..f0641a50e8 100644
--- a/include/iocore/eventsystem/EThread.h
+++ b/include/iocore/eventsystem/EThread.h
@@ -24,6 +24,8 @@
 
 #pragma once
 
+#include <atomic>
+
 #include "tscore/ink_platform.h"
 #include "tscore/ink_rand.h"
 #include "tscore/Version.h"
@@ -479,7 +481,7 @@ public:
     /// The slices.
     std::array<Slice, N_SLICES> _slice;
 
-    Slice *volatile current_slice = nullptr; ///< The current slice.
+    std::atomic<Slice *> current_slice{nullptr}; ///< The current slice.
 
     /** The number of time scales used in the event statistics.
         Currently these are 10s, 100s, 1000s.
@@ -599,7 +601,7 @@ inline auto
 EThread::Metrics::record_loop_time(ink_hrtime delta) -> self_type &
 {
   static auto constexpr DIVISOR = std::chrono::duration_cast<ts_nanoseconds>(LOOP_HISTOGRAM_BUCKET_SIZE).count();
-  current_slice->record_loop_duration(delta);
+  (*current_slice).record_loop_duration(delta);
   _loop_timing(delta / DIVISOR);
   return *this;
 }
diff --git a/src/iocore/eventsystem/UnixEThread.cc b/src/iocore/eventsystem/UnixEThread.cc
index 492b442cfe..0566a1c598 100644
--- a/src/iocore/eventsystem/UnixEThread.cc
+++ b/src/iocore/eventsystem/UnixEThread.cc
@@ -234,9 +234,9 @@ EThread::execute_regular()
         // Need @c const_cast to cast away @c volatile
         memcpy(prev_slice = this->metrics.next_slice(prev_slice), &SLICE_INIT, sizeof(SLICE_INIT));
       } while (metrics.current_slice != prev_slice);
-      metrics.current_slice->record_loop_start(loop_start_time);
+      (*metrics.current_slice).record_loop_start(loop_start_time);
     }
-    ++(metrics.current_slice->_count); // loop started, bump count.
+    ++((*metrics.current_slice)._count); // loop started, bump count.
 
     process_queue(&NegativeQueue, &ev_count, &nq_count);
 
@@ -277,7 +277,7 @@ EThread::execute_regular()
         // Therefore, we have to set the limitation of sleep time in order to handle the next retry in time.
         sleep_time = std::min(sleep_time, DELAY_FOR_RETRY);
       }
-      ++(metrics.current_slice->_wait);
+      ++((*metrics.current_slice)._wait);
     } else {
       sleep_time = 0;
     }
@@ -293,7 +293,7 @@ EThread::execute_regular()
 
     metrics.decay();
     metrics.record_loop_time(delta);
-    metrics.current_slice->record_event_count(ev_count);
+    (*metrics.current_slice).record_event_count(ev_count);
   }
 }