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Diffstat (limited to 'arch/x86/kernel/process_64.c')
-rw-r--r--arch/x86/kernel/process_64.c58
1 files changed, 16 insertions, 42 deletions
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index c958120f..416fb92 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -39,6 +39,7 @@
#include <linux/prctl.h>
#include <linux/uaccess.h>
#include <linux/io.h>
+#include <linux/ftrace.h>
#include <asm/pgtable.h>
#include <asm/system.h>
@@ -52,6 +53,7 @@
#include <asm/ia32.h>
#include <asm/idle.h>
#include <asm/syscalls.h>
+#include <asm/ds.h>
asmlinkage extern void ret_from_fork(void);
@@ -235,14 +237,8 @@ void exit_thread(void)
t->io_bitmap_max = 0;
put_cpu();
}
-#ifdef CONFIG_X86_DS
- /* Free any DS contexts that have not been properly released. */
- if (unlikely(t->ds_ctx)) {
- /* we clear debugctl to make sure DS is not used. */
- update_debugctlmsr(0);
- ds_free(t->ds_ctx);
- }
-#endif /* CONFIG_X86_DS */
+
+ ds_exit_thread(current);
}
void flush_thread(void)
@@ -372,6 +368,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
if (err)
goto out;
}
+
+ ds_copy_thread(p, me);
+
+ clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
+ p->thread.debugctlmsr = 0;
+
err = 0;
out:
if (err && p->thread.io_bitmap_ptr) {
@@ -470,35 +472,14 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
struct tss_struct *tss)
{
struct thread_struct *prev, *next;
- unsigned long debugctl;
prev = &prev_p->thread,
next = &next_p->thread;
- debugctl = prev->debugctlmsr;
-
-#ifdef CONFIG_X86_DS
- {
- unsigned long ds_prev = 0, ds_next = 0;
-
- if (prev->ds_ctx)
- ds_prev = (unsigned long)prev->ds_ctx->ds;
- if (next->ds_ctx)
- ds_next = (unsigned long)next->ds_ctx->ds;
-
- 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 */
-
- if (next->debugctlmsr != debugctl)
+ if (test_tsk_thread_flag(next_p, TIF_DS_AREA_MSR) ||
+ test_tsk_thread_flag(prev_p, TIF_DS_AREA_MSR))
+ ds_switch_to(prev_p, next_p);
+ else if (next->debugctlmsr != prev->debugctlmsr)
update_debugctlmsr(next->debugctlmsr);
if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
@@ -533,14 +514,6 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
*/
memset(tss->io_bitmap, 0xff, prev->io_bitmap_max);
}
-
-#ifdef CONFIG_X86_PTRACE_BTS
- if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS))
- ptrace_bts_take_timestamp(prev_p, BTS_TASK_DEPARTS);
-
- if (test_tsk_thread_flag(next_p, TIF_BTS_TRACE_TS))
- ptrace_bts_take_timestamp(next_p, BTS_TASK_ARRIVES);
-#endif /* CONFIG_X86_PTRACE_BTS */
}
/*
@@ -551,8 +524,9 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
* - could test fs/gs bitsliced
*
* Kprobes not supported here. Set the probe on schedule instead.
+ * Function graph tracer not supported too.
*/
-struct task_struct *
+__notrace_funcgraph struct task_struct *
__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
{
struct thread_struct *prev = &prev_p->thread;
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