[release/9.0-staging] handle case of Proc Index > MAX_SUPPORTED_CPUS (#109385)

github-actions[bot] · mangod9 · web-flow · commit d31f39417d7e · 2024-11-06T13:29:55.000-08:00
* handle case of Proc Index &gt; MAX_SUPPORTED_CPUS

* PR feedback

* Update comment

---------

Co-authored-by: Manish Godse &lt;61718172+mangod9@users.noreply.github.com&gt;
diff --git a/src/coreclr/gc/gc.cpp b/src/coreclr/gc/gc.cpp
@@ -6404,7 +6404,11 @@ class heap_select
         if (GCToOSInterface::CanGetCurrentProcessorNumber())
         {
             uint32_t proc_no = GCToOSInterface::GetCurrentProcessorNumber();
-            proc_no_to_heap_no[proc_no] = (uint16_t)heap_number;
+            // For a 32-bit process running on a machine with > 64 procs, 
+            // even though the process can only use up to 32 procs, the processor 
+            // index can be >= 64; or in the cpu group case, if the process is not running in cpu group #0, 
+            // the GetCurrentProcessorNumber will return a number that's >= 64.
+            proc_no_to_heap_no[proc_no % MAX_SUPPORTED_CPUS] = (uint16_t)heap_number;
         }
     }
 
@@ -6426,7 +6430,11 @@ class heap_select
         if (GCToOSInterface::CanGetCurrentProcessorNumber())
         {
             uint32_t proc_no = GCToOSInterface::GetCurrentProcessorNumber();
-            int adjusted_heap = proc_no_to_heap_no[proc_no];
+            // For a 32-bit process running on a machine with > 64 procs, 
+            // even though the process can only use up to 32 procs, the processor 
+            // index can be >= 64; or in the cpu group case, if the process is not running in cpu group #0, 
+            // the GetCurrentProcessorNumber will return a number that's >= 64.
+            int adjusted_heap = proc_no_to_heap_no[proc_no % MAX_SUPPORTED_CPUS];
             // with dynamic heap count, need to make sure the value is in range.
             if (adjusted_heap >= gc_heap::n_heaps)
             {

Original file line number	Diff line number	Diff line change
`@@ -6404,7 +6404,11 @@ class heap_select`
`6404`	`6404`	`if (GCToOSInterface::CanGetCurrentProcessorNumber())`
`6405`	`6405`	`{`
`6406`	`6406`	`uint32_t proc_no = GCToOSInterface::GetCurrentProcessorNumber();`
`6407`		`- proc_no_to_heap_no[proc_no] = (uint16_t)heap_number;`
	`6407`	`+ // For a 32-bit process running on a machine with > 64 procs,`
	`6408`	`+ // even though the process can only use up to 32 procs, the processor`
	`6409`	`+ // index can be >= 64; or in the cpu group case, if the process is not running in cpu group #0,`
	`6410`	`+ // the GetCurrentProcessorNumber will return a number that's >= 64.`
	`6411`	`+ proc_no_to_heap_no[proc_no % MAX_SUPPORTED_CPUS] = (uint16_t)heap_number;`
`6408`	`6412`	`}`
`6409`	`6413`	`}`
`6410`	`6414`
`@@ -6426,7 +6430,11 @@ class heap_select`
`6426`	`6430`	`if (GCToOSInterface::CanGetCurrentProcessorNumber())`
`6427`	`6431`	`{`
`6428`	`6432`	`uint32_t proc_no = GCToOSInterface::GetCurrentProcessorNumber();`
`6429`		`- int adjusted_heap = proc_no_to_heap_no[proc_no];`
	`6433`	`+ // For a 32-bit process running on a machine with > 64 procs,`
	`6434`	`+ // even though the process can only use up to 32 procs, the processor`
	`6435`	`+ // index can be >= 64; or in the cpu group case, if the process is not running in cpu group #0,`
	`6436`	`+ // the GetCurrentProcessorNumber will return a number that's >= 64.`
	`6437`	`+ int adjusted_heap = proc_no_to_heap_no[proc_no % MAX_SUPPORTED_CPUS];`
`6430`	`6438`	`// with dynamic heap count, need to make sure the value is in range.`
`6431`	`6439`	`if (adjusted_heap >= gc_heap::n_heaps)`
`6432`	`6440`	`{`