Changeset 358cba0 for src/libcfa/concurrency/coroutine

Timestamp:

May 15, 2018, 4:17:15 PM (7 years ago)

Author:

Rob Schluntz <rschlunt@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, with_gc

Children:

2e5fa345

Parents:

7d0a3ba (diff), a61fa0bb (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge branch 'master' of plg.uwaterloo.ca:/u/cforall/software/cfa/cfa-cc

File:

• src/libcfa/concurrency/coroutine (modified) (5 diffs)

src/libcfa/concurrency/coroutine

@@ -72 +72 @@
 // Suspend implementation inlined for performance
 static inline void suspend() {
-        coroutine_desc * src = TL_GET( this_coroutine );                        // optimization
+        // optimization : read TLS once and reuse it
+        // Safety note: this is preemption safe since if
+        // preemption occurs after this line, the pointer
+        // will also migrate which means this value will
+        // stay in syn with the TLS
+        coroutine_desc * src = TL_GET( this_coroutine );
 
         assertf( src->last != 0,
@@ -89 +94 @@
 forall(dtype T | is_coroutine(T))
 static inline void resume(T & cor) {
-        coroutine_desc * src = TL_GET( this_coroutine );                        // optimization
+        // optimization : read TLS once and reuse it
+        // Safety note: this is preemption safe since if
+        // preemption occurs after this line, the pointer
+        // will also migrate which means this value will
+        // stay in syn with the TLS
+        coroutine_desc * src = TL_GET( this_coroutine );
         coroutine_desc * dst = get_coroutine(cor);
 
@@ -107 +117 @@
                 dst->last = src;
                 dst->starter = dst->starter ? dst->starter : src;
-        } // if
+        }
 
         // always done for performance testing
@@ -114 +124 @@
 
 static inline void resume(coroutine_desc * dst) {
-        coroutine_desc * src = TL_GET( this_coroutine );                        // optimization
+        // optimization : read TLS once and reuse it
+        // Safety note: this is preemption safe since if
+        // preemption occurs after this line, the pointer
+        // will also migrate which means this value will
+        // stay in syn with the TLS
+        coroutine_desc * src = TL_GET( this_coroutine );
 
         // not resuming self ?
@@ -125 +140 @@
                 // set last resumer
                 dst->last = src;
-        } // if
+        }
 
         // always done for performance testing