commit 7b543a5334ff4ea2e3ad3b777fc23cdb8072a988
author Tejun Heo <tj@kernel.org> Sat Dec 18 16:30:05 2010 +0100
committer Tejun Heo <tj@kernel.org> Thu Dec 30 12:22:03 2010 +0100
tree 8fbdf5275411190f78f3bdee3c40e87285bf8e30
parent 0a3aee0da4402aa19b66e458038533c896fb80c6

x86: Replace uses of current_cpu_data with this_cpu ops

Replace all uses of current_cpu_data with this_cpu operations on the
per cpu structure cpu_info.  The scala accesses are replaced with the
matching this_cpu ops which results in smaller and more efficient
code.

In the long run, it might be a good idea to remove cpu_data() macro
too and use per_cpu macro directly.

tj: updated description

Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

arch/x86/kernel/smpboot.c

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index ff4e5a1..0720071 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -430,7 +430,7 @@
 
 	cpumask_set_cpu(cpu, c->llc_shared_map);
 
-	if (current_cpu_data.x86_max_cores == 1) {
+	if (__this_cpu_read(cpu_info.x86_max_cores) == 1) {
 		cpumask_copy(cpu_core_mask(cpu), cpu_sibling_mask(cpu));
 		c->booted_cores = 1;
 		return;
@@ -1094,7 +1094,7 @@
 
 	preempt_disable();
 	smp_cpu_index_default();
-	current_cpu_data = boot_cpu_data;
+	memcpy(__this_cpu_ptr(&cpu_info), &boot_cpu_data, sizeof(cpu_info));
 	cpumask_copy(cpu_callin_mask, cpumask_of(0));
 	mb();
 	/*
@@ -1397,11 +1397,11 @@
 	int i;
 	void *mwait_ptr;
 
-	if (!cpu_has(&current_cpu_data, X86_FEATURE_MWAIT))
+	if (!cpu_has(__this_cpu_ptr(&cpu_info), X86_FEATURE_MWAIT))
 		return;
-	if (!cpu_has(&current_cpu_data, X86_FEATURE_CLFLSH))
+	if (!cpu_has(__this_cpu_ptr(&cpu_info), X86_FEATURE_CLFLSH))
 		return;
-	if (current_cpu_data.cpuid_level < CPUID_MWAIT_LEAF)
+	if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF)
 		return;
 
 	eax = CPUID_MWAIT_LEAF;
@@ -1452,7 +1452,7 @@
 
 static inline void hlt_play_dead(void)
 {
-	if (current_cpu_data.x86 >= 4)
+	if (__this_cpu_read(cpu_info.x86) >= 4)
 		wbinvd();
 
 	while (1) {