[PATCH] [45/45] i386: simplify smp_call_function_single() call sequence

Andi Kleen
2007-09-21T21:00:21Z

From: Avi Kivity <avi@qumranet.com>

smp_call_function_single() now knows how to call the function on the
current cpu.

Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

arch/i386/lib/msr-on-cpu.c | 62 +++++++++++++++------------------------------
1 file changed, 22 insertions(+), 40 deletions(-)

Index: linux/arch/i386/lib/msr-on-cpu.c
===================================================================
--- linux.orig/arch/i386/lib/msr-on-cpu.c
+++ linux/arch/i386/lib/msr-on-cpu.c
@@ -26,27 +26,18 @@ static void __rdmsr_safe_on_cpu(void *in
static int _rdmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 *l, u32 *h, int safe)
{
int err = 0;
- preempt_disable();
- if (smp_processor_id() == cpu)
- if (safe)
- err = rdmsr_safe(msr_no, l, h);
- else
- rdmsr(msr_no, *l, *h);
- else {
- struct msr_info rv;
-
- rv.msr_no = msr_no;
- if (safe) {
- smp_call_function_single(cpu, __rdmsr_safe_on_cpu,
- &rv, 0, 1);
- err = rv.err;
- } else {
- smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1);
- }
- *l = rv.l;
- *h = rv.h;
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ if (safe) {
+ smp_call_function_single(cpu, __rdmsr_safe_on_cpu, &rv, 0, 1);
+ err = rv.err;
+ } else {
+ smp_call_function_single(cpu, __rdmsr_on_cpu, &rv, 0, 1);
}
- preempt_enable();
+ *l = rv.l;
+ *h = rv.h;
+
return err;
}

@@ -67,27 +58,18 @@ static void __wrmsr_safe_on_cpu(void *in
static int _wrmsr_on_cpu(unsigned int cpu, u32 msr_no, u32 l, u32 h, int safe)
{
int err = 0;
- preempt_disable();
- if (smp_processor_id() == cpu)
- if (safe)
- err = wrmsr_safe(msr_no, l, h);
- else
- wrmsr(msr_no, l, h);
- else {
- struct msr_info rv;
-
- rv.msr_no = msr_no;
- rv.l = l;
- rv.h = h;
- if (safe) {
- smp_call_function_single(cpu, __wrmsr_safe_on_cpu,
- &rv, 0, 1);
- err = rv.err;
- } else {
- smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1);
- }
+ struct msr_info rv;
+
+ rv.msr_no = msr_no;
+ rv.l = l;
+ rv.h = h;
+ if (safe) {
+ smp_call_function_single(cpu, __wrmsr_safe_on_cpu, &rv, 0, 1);
+ err = rv.err;
+ } else {
+ smp_call_function_single(cpu, __wrmsr_on_cpu, &rv, 0, 1);
}
- preempt_enable();
+
return err;
}