x86: use bitmap library for pin_programmed

[linux-2.6] / arch / x86 / kernel / process_64.c

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index e75ccc8a2b87b7e659e0ee4c8ad74459239b98bb..131c2ee7ac5618e9fc92f576f4db19676bd235af 100644 (file)
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -36,6 +36,7 @@
 #include <linux/kprobes.h>
 #include <linux/kdebug.h>
 #include <linux/tick.h>
+#include <linux/prctl.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -532,9 +533,71 @@ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp)
        regs->ss                = __USER_DS;
        regs->flags             = 0x200;
        set_fs(USER_DS);
+       /*
+        * Free the old FP and other extended state
+        */
+       free_thread_xstate(current);
 }
 EXPORT_SYMBOL_GPL(start_thread);
 
+static void hard_disable_TSC(void)
+{
+       write_cr4(read_cr4() | X86_CR4_TSD);
+}
+
+void disable_TSC(void)
+{
+       preempt_disable();
+       if (!test_and_set_thread_flag(TIF_NOTSC))
+               /*
+                * Must flip the CPU state synchronously with
+                * TIF_NOTSC in the current running context.
+                */
+               hard_disable_TSC();
+       preempt_enable();
+}
+
+static void hard_enable_TSC(void)
+{
+       write_cr4(read_cr4() & ~X86_CR4_TSD);
+}
+
+static void enable_TSC(void)
+{
+       preempt_disable();
+       if (test_and_clear_thread_flag(TIF_NOTSC))
+               /*
+                * Must flip the CPU state synchronously with
+                * TIF_NOTSC in the current running context.
+                */
+               hard_enable_TSC();
+       preempt_enable();
+}
+
+int get_tsc_mode(unsigned long adr)
+{
+       unsigned int val;
+
+       if (test_thread_flag(TIF_NOTSC))
+               val = PR_TSC_SIGSEGV;
+       else
+               val = PR_TSC_ENABLE;
+
+       return put_user(val, (unsigned int __user *)adr);
+}
+
+int set_tsc_mode(unsigned int val)
+{
+       if (val == PR_TSC_SIGSEGV)
+               disable_TSC();
+       else if (val == PR_TSC_ENABLE)
+               enable_TSC();
+       else
+               return -EINVAL;
+
+       return 0;
+}
+
 /*
  * This special macro can be used to load a debugging register
  */
@@ -572,6 +635,15 @@ static inline void __switch_to_xtra(struct task_struct *prev_p,
                loaddebug(next, 7);
        }
 
+       if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
+           test_tsk_thread_flag(next_p, TIF_NOTSC)) {
+               /* prev and next are different */
+               if (test_tsk_thread_flag(next_p, TIF_NOTSC))
+                       hard_disable_TSC();
+               else
+                       hard_enable_TSC();
+       }
+
        if (test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
                /*
                 * Copy the relevant range of the IO bitmap.
@@ -614,7 +686,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 
        /* we're going to use this soon, after a few expensive things */
        if (next_p->fpu_counter>5)
-               prefetch(&next->i387.fxsave);
+               prefetch(next->xstate);
 
        /*
         * Reload esp0, LDT and the page table pointer: