lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

x86: PEBS cleanup

Browse Source 
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar
2008-05-17 08:30:07 +02:00
committed by Thomas Gleixner
parent 573da4224e
commit 34b2cd5b68
1 changed files with 16 additions and 11 deletions
Download Patch File Download Diff File Expand all files Collapse all files

27
arch/x86/kernel/process_64.c
View File

@@ -500,7 +500,6 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
{ {
struct thread_struct *prev, *next; struct thread_struct *prev, *next;
unsigned long debugctl; unsigned long debugctl;
unsigned long ds_prev = 0, ds_next = 0;
prev = &prev_p->thread, prev = &prev_p->thread,
next = &next_p->thread; next = &next_p->thread;
@@ -508,17 +507,23 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
debugctl = prev->debugctlmsr; debugctl = prev->debugctlmsr;
#ifdef CONFIG_X86_DS #ifdef CONFIG_X86_DS
if (prev->ds_ctx) {
ds_prev = (unsigned long)prev->ds_ctx->ds; unsigned long ds_prev = 0, ds_next = 0;
if (next->ds_ctx)
ds_next = (unsigned long)next->ds_ctx->ds;
if (ds_next != ds_prev) { if (prev->ds_ctx)
/* we clear debugctl to make sure DS ds_prev = (unsigned long)prev->ds_ctx->ds;
* is not in use when we change it */ if (next->ds_ctx)
debugctl = 0; ds_next = (unsigned long)next->ds_ctx->ds;
update_debugctlmsr(0);
wrmsrl(MSR_IA32_DS_AREA, ds_next); if (ds_next != ds_prev) {
/*
* We clear debugctl to make sure DS
* is not in use when we change it:
*/
debugctl = 0;
update_debugctlmsr(0);
wrmsrl(MSR_IA32_DS_AREA, ds_next);
}
} }
#endif /* CONFIG_X86_DS */ #endif /* CONFIG_X86_DS */