]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - arch/x86/kernel/process_32.c
x86, bts: add fork and exit handling
[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / process_32.c
index 0a1302fe6d45307ffa880ed9e355050a194518af..3ba155d24884dd812790ff0e5aef8bb6767100d0 100644 (file)
@@ -38,6 +38,7 @@
 #include <linux/percpu.h>
 #include <linux/prctl.h>
 #include <linux/dmi.h>
+#include <linux/ftrace.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -59,6 +60,7 @@
 #include <asm/idle.h>
 #include <asm/syscalls.h>
 #include <asm/smp.h>
+#include <asm/ds.h>
 
 asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
 
@@ -250,14 +252,8 @@ void exit_thread(void)
                tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
                put_cpu();
        }
-#ifdef CONFIG_X86_DS
-       /* Free any DS contexts that have not been properly released. */
-       if (unlikely(current->thread.ds_ctx)) {
-               /* we clear debugctl to make sure DS is not used. */
-               update_debugctlmsr(0);
-               ds_free(current->thread.ds_ctx);
-       }
-#endif /* CONFIG_X86_DS */
+
+       ds_exit_thread(current);
 }
 
 void flush_thread(void)
@@ -339,6 +335,12 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
                kfree(p->thread.io_bitmap_ptr);
                p->thread.io_bitmap_max = 0;
        }
+
+       ds_copy_thread(p, current);
+
+       clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
+       p->thread.debugctlmsr = 0;
+
        return err;
 }
 
@@ -419,48 +421,19 @@ int set_tsc_mode(unsigned int val)
        return 0;
 }
 
-#ifdef CONFIG_X86_DS
-static int update_debugctl(struct thread_struct *prev,
-                       struct thread_struct *next, unsigned long debugctl)
-{
-       unsigned long ds_prev = 0;
-       unsigned long 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);
-               wrmsr(MSR_IA32_DS_AREA, ds_next, 0);
-       }
-       return debugctl;
-}
-#else
-static int update_debugctl(struct thread_struct *prev,
-                       struct thread_struct *next, unsigned long debugctl)
-{
-       return debugctl;
-}
-#endif /* CONFIG_X86_DS */
-
 static noinline void
 __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
                 struct tss_struct *tss)
 {
        struct thread_struct *prev, *next;
-       unsigned long debugctl;
 
        prev = &prev_p->thread;
        next = &next_p->thread;
 
-       debugctl = update_debugctl(prev, next, prev->debugctlmsr);
-
-       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)) {
@@ -482,15 +455,6 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
                        hard_enable_TSC();
        }
 
-#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 */
-
-
        if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
                /*
                 * Disable the bitmap via an invalid offset. We still cache
@@ -548,7 +512,8 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
  * the task-switch, and shows up in ret_from_fork in entry.S,
  * for example.
  */
-struct task_struct * __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
+__notrace_funcgraph struct task_struct *
+__switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 {
        struct thread_struct *prev = &prev_p->thread,
                                 *next = &next_p->thread;