summaryrefslogtreecommitdiff
path: root/arch/x86/entry
diff options
context:
space:
mode:
authorChang S. Bae <chang.seok.bae@intel.com>2018-09-19 02:08:58 +0300
committerIngo Molnar <mingo@kernel.org>2018-10-08 11:41:10 +0300
commitffebbaedc8616cffe648202e364dce6a045d65a2 (patch)
treedb77803dfcd20c32ec9703f8d382943479941559 /arch/x86/entry
parentc4755613a1339ea77dbb15de75c9f74217209265 (diff)
downloadlinux-ffebbaedc8616cffe648202e364dce6a045d65a2.tar.xz
x86/vdso: Introduce helper functions for CPU and node number
Clean up the CPU/node number related code a bit, to make it more apparent how we are encoding/extracting the CPU and node fields from the segment limit. No change in functionality intended. [ mingo: Wrote new changelog. ] Suggested-by: Andy Lutomirski <luto@kernel.org> Suggested-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Markus T Metzger <markus.t.metzger@intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Shankar <ravi.v.shankar@intel.com> Cc: Rik van Riel <riel@surriel.com> Link: http://lkml.kernel.org/r/1537312139-5580-8-git-send-email-chang.seok.bae@intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/entry')
-rw-r--r--arch/x86/entry/vdso/vgetcpu.c9
-rw-r--r--arch/x86/entry/vdso/vma.c19
2 files changed, 8 insertions, 20 deletions
diff --git a/arch/x86/entry/vdso/vgetcpu.c b/arch/x86/entry/vdso/vgetcpu.c
index 8ec3d1f4ce9a..de78fc9cd963 100644
--- a/arch/x86/entry/vdso/vgetcpu.c
+++ b/arch/x86/entry/vdso/vgetcpu.c
@@ -13,14 +13,7 @@
notrace long
__vdso_getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *unused)
{
- unsigned int p;
-
- p = __getcpu();
-
- if (cpu)
- *cpu = p & VGETCPU_CPU_MASK;
- if (node)
- *node = p >> 12;
+ vdso_read_cpu_node(cpu, node);
return 0;
}
diff --git a/arch/x86/entry/vdso/vma.c b/arch/x86/entry/vdso/vma.c
index 0b114aafcedc..39b5584c5808 100644
--- a/arch/x86/entry/vdso/vma.c
+++ b/arch/x86/entry/vdso/vma.c
@@ -339,20 +339,15 @@ static void vgetcpu_cpu_init(void *arg)
{
int cpu = smp_processor_id();
struct desc_struct d = { };
- unsigned long node = 0;
-#ifdef CONFIG_NUMA
- node = cpu_to_node(cpu);
-#endif
+ unsigned long cpudata = vdso_encode_cpu_node(cpu, cpu_to_node(cpu));
+
if (static_cpu_has(X86_FEATURE_RDTSCP))
- write_rdtscp_aux((node << 12) | cpu);
+ write_rdtscp_aux(cpudata);
+
+ /* Store CPU and node number in limit */
+ d.limit0 = cpudata;
+ d.limit1 = cpudata >> 16;
- /*
- * Store cpu number in limit so that it can be loaded
- * quickly in user space in vgetcpu. (12 bits for the CPU
- * and 8 bits for the node)
- */
- d.limit0 = cpu | ((node & 0xf) << 12);
- d.limit1 = node >> 4;
d.type = 5; /* RO data, expand down, accessed */
d.dpl = 3; /* Visible to user code */
d.s = 1; /* Not a system segment */