diff options
| author | Yazen Ghannam <Yazen.Ghannam@amd.com> | 2017-02-05 11:50:22 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-02-05 12:18:45 +0100 |
| commit | 08b259631b5a1d912af4832847b5642f377d9101 (patch) | |
| tree | 3a77b453bac2a4e76f4e12d1c40d4c07f3f3258d | |
| parent | 79a8b9aa388b0620cc1d525d7c0f0d9a8a85e08e (diff) | |
| download | linux-08b259631b5a1d912af4832847b5642f377d9101.tar.bz2 | |
x86/CPU/AMD: Fix Zen SMT topology
After:
a33d331761bc ("x86/CPU/AMD: Fix Bulldozer topology")
our SMT scheduling topology for Fam17h systems is broken, because
the ThreadId is included in the ApicId when SMT is enabled.
So, without further decoding cpu_core_id is unique for each thread
rather than the same for threads on the same core. This didn't affect
systems with SMT disabled. Make cpu_core_id be what it is defined to be.
Signed-off-by: Yazen Ghannam <Yazen.Ghannam@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: <stable@vger.kernel.org> # 4.9
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170205105022.8705-2-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
| -rw-r--r-- | arch/x86/kernel/cpu/amd.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index 20dc44d1e6be..2b4cf04239b6 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -319,6 +319,13 @@ static void amd_get_topology(struct cpuinfo_x86 *c) if (c->x86 == 0x15) c->cu_id = ebx & 0xff; + if (c->x86 >= 0x17) { + c->cpu_core_id = ebx & 0xff; + + if (smp_num_siblings > 1) + c->x86_max_cores /= smp_num_siblings; + } + /* * We may have multiple LLCs if L3 caches exist, so check if we * have an L3 cache by looking at the L3 cache CPUID leaf. |