Changeset bd0bdd37

Timestamp:

Mar 25, 2021, 3:09:01 PM (4 years ago)

Author:

Thierry Delisle <tdelisle@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

08e75215, 2d95a2d

Parents:

3143f28

Message:

Fix how bias is handled in the ready queue to be more consistent with multiple clusters.
Does not handle churn of processors yet.

Location:

libcfa/src/concurrency

Files:

• kernel.hfa (modified) (1 diff)
• kernel/startup.cfa (modified) (1 diff)
• kernel_private.hfa (modified) (1 diff)
• ready_queue.cfa (modified) (5 diffs)

libcfa/src/concurrency/kernel.hfa

@@ -69 +69 @@
         // Cluster from which to get threads
         struct cluster * cltr;
+
+        // Id within the cluster
+        unsigned cltr_id;
 
         // Set to true to notify the processor should terminate

libcfa/src/concurrency/kernel/startup.cfa

@@ -486 +486 @@
 
                 // Adjust the ready queue size
-                ready_queue_grow( cltr, target );
+                this.cltr_id = ready_queue_grow( cltr, target );
 
         // Unlock the RWlock

libcfa/src/concurrency/kernel_private.hfa

@@ -278 +278 @@
 //-----------------------------------------------------------------------
 // Increase the width of the ready queue (number of lanes) by 4
-void ready_queue_grow  (struct cluster * cltr, int target);
+unsigned ready_queue_grow  (struct cluster * cltr, int target);
 
 //-----------------------------------------------------------------------

libcfa/src/concurrency/ready_queue.cfa

@@ -252 +252 @@
                 preferred =
                         //*
-                        kernelTLS().this_processor ? kernelTLS().this_processor->id * 4 : -1;
+                        kernelTLS().this_processor ? kernelTLS().this_processor->cltr_id : -1;
                         /*/
                         thrd->link.preferred * 4;
@@ -330 +330 @@
         #if defined(BIAS)
                 // Don't bother trying locally too much
-                preferred = kernelTLS().this_processor->id * 4;
+                preferred = kernelTLS().this_processor->cltr_id;
         #endif
 
@@ -525 +525 @@
 
 // Grow the ready queue
-void ready_queue_grow  (struct cluster * cltr, int target) {
+unsigned ready_queue_grow(struct cluster * cltr, int target) {
+        unsigned preferred;
+        size_t ncount;
+
         /* paranoid */ verify( ready_mutate_islocked() );
         __cfadbg_print_safe(ready_queue, "Kernel : Growing ready queue\n");
@@ -540 +543 @@
                 // Find new count
                 // Make sure we always have atleast 1 list
-                size_t ncount = target >= 2 ? target * 4: 1;
+                if(target >= 2) {
+                        ncount = target * 4;
+                        preferred = ncount - 4;
+                } else {
+                        ncount = 1;
+                        preferred = 0;
+                }
 
                 // Allocate new array (uses realloc and memcpies the data)
@@ -575 +584 @@
 
         /* paranoid */ verify( ready_mutate_islocked() );
+        return preferred;
 }