diff options
Diffstat (limited to 'sysdeps')
| -rw-r--r-- | sysdeps/x86/dl-cacheinfo.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/sysdeps/x86/dl-cacheinfo.h b/sysdeps/x86/dl-cacheinfo.h index ec88945..877e73d 100644 --- a/sysdeps/x86/dl-cacheinfo.h +++ b/sysdeps/x86/dl-cacheinfo.h @@ -749,8 +749,16 @@ dl_init_cacheinfo (struct cpu_features *cpu_features) reflected in the manual. */ unsigned long int maximum_non_temporal_threshold = SIZE_MAX >> 4; unsigned long int minimum_non_temporal_threshold = 0x4040; + + /* If `non_temporal_threshold` less than `minimum_non_temporal_threshold` + it most likely means we failed to detect the cache info. We don't want + to default to `minimum_non_temporal_threshold` as such a small value, + while correct, has bad performance. We default to 64MB as reasonable + default bound. 64MB is likely conservative in that most/all systems would + choose a lower value so it should never forcing non-temporal stores when + they otherwise wouldn't be used. */ if (non_temporal_threshold < minimum_non_temporal_threshold) - non_temporal_threshold = minimum_non_temporal_threshold; + non_temporal_threshold = 64 * 1024 * 1024; else if (non_temporal_threshold > maximum_non_temporal_threshold) non_temporal_threshold = maximum_non_temporal_threshold; |