diff options
Diffstat (limited to 'sysdeps/x86_64/cacheinfo.c')
| -rw-r--r-- | sysdeps/x86_64/cacheinfo.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/sysdeps/x86_64/cacheinfo.c b/sysdeps/x86_64/cacheinfo.c index f1cbf50957..b99fb9a762 100644 --- a/sysdeps/x86_64/cacheinfo.c +++ b/sysdeps/x86_64/cacheinfo.c @@ -585,6 +585,10 @@ init_cacheinfo (void) __cpuid (1, eax, ebx_1, ecx, edx); #endif + unsigned int family = (eax >> 8) & 0x0f; + unsigned int model = (eax >> 4) & 0x0f; + unsigned int extended_model = (eax >> 12) & 0xf0; + #ifndef DISABLE_PREFERRED_MEMORY_INSTRUCTION /* Intel prefers SSSE3 instructions for memory/string routines if they are available. */ @@ -647,6 +651,25 @@ init_cacheinfo (void) } } threads += 1; + if (threads > 2 && level == 2 && family == 6) + { + model += extended_model; + switch (model) + { + case 0x57: + /* Knights Landing has L2 cache shared by 2 cores. */ + case 0x37: + case 0x4a: + case 0x4d: + case 0x5a: + case 0x5d: + /* Silvermont has L2 cache shared by 2 cores. */ + threads = 2; + break; + default: + break; + } + } } else { |