On Fri, Oct 15, 2021 at 12:26:34PM -0700, sunil.k.pandey wrote:
> 4764049dd620affcd3e2658dc7f03a6616370a29 is the first bad commit
> commit 4764049dd620affcd3e2658dc7f03a6616370a29
> Author: Jakub Jelinek <ja...@redhat.com>
> Date:   Fri Oct 15 16:25:25 2021 +0200
> 
>     openmp: Fix up handling of OMP_PLACES=threads(1)
> 
> caused
> 
> FAIL: libgomp.c/places-10.c execution test

Reproduced on gcc112 in CompileFarm (my ws isn't NUMA).
If numa-domains is used with num-places count, sometimes the function
could create more places than requested and crash.  This depended on the
content of /sys/devices/system/node/online file, e.g. if the file
contains
0-1,16-17
and all NUMA nodes contain at least one CPU in the cpuset of the program,
then numa_domains(2) or numa_domains(4) (or 5+) work fine while
numa_domains(1) or numa_domains(3) misbehave.  I.e. the function was able
to stop after reaching limit on the , separators (or trivially at the end),
but not within in the ranges.

Fixed thusly, tested on powerpc64le-linux, committed to trunk.

2021-10-18  Jakub Jelinek  <ja...@redhat.com>

        * config/linux/affinity.c (gomp_affinity_init_numa_domains): Add
        && gomp_places_list_len < count after nfirst <= nlast loop condition.

--- libgomp/config/linux/affinity.c.jj  2021-10-15 16:28:30.374460522 +0200
+++ libgomp/config/linux/affinity.c     2021-10-18 14:44:51.559667127 +0200
@@ -401,7 +401,7 @@ gomp_affinity_init_numa_domains (unsigne
            break;
          q = end;
        }
-      for (; nfirst <= nlast; nfirst++)
+      for (; nfirst <= nlast && gomp_places_list_len < count; nfirst++)
        {
          sprintf (name + prefix_len, "node%lu/cpulist", nfirst);
          f = fopen (name, "r");


        Jakub

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