arch: Cleanup enable/disable_hlt
[linux-3.10.git] / arch / microblaze / kernel / process.c
index c592d47..7c36171 100644 (file)
@@ -8,55 +8,44 @@
  * for more details.
  */
 
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/sched.h>
 #include <linux/pm.h>
 #include <linux/tick.h>
 #include <linux/bitops.h>
-#include <asm/system.h>
+#include <linux/ptrace.h>
 #include <asm/pgalloc.h>
+#include <linux/uaccess.h> /* for USER_DS macros */
+#include <asm/cacheflush.h>
 
 void show_regs(struct pt_regs *regs)
 {
-       printk(KERN_INFO " Registers dump: mode=%X\r\n", regs->pt_mode);
-       printk(KERN_INFO " r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n",
+       pr_info(" Registers dump: mode=%X\r\n", regs->pt_mode);
+       pr_info(" r1=%08lX, r2=%08lX, r3=%08lX, r4=%08lX\n",
                                regs->r1, regs->r2, regs->r3, regs->r4);
-       printk(KERN_INFO " r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n",
+       pr_info(" r5=%08lX, r6=%08lX, r7=%08lX, r8=%08lX\n",
                                regs->r5, regs->r6, regs->r7, regs->r8);
-       printk(KERN_INFO " r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n",
+       pr_info(" r9=%08lX, r10=%08lX, r11=%08lX, r12=%08lX\n",
                                regs->r9, regs->r10, regs->r11, regs->r12);
-       printk(KERN_INFO " r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n",
+       pr_info(" r13=%08lX, r14=%08lX, r15=%08lX, r16=%08lX\n",
                                regs->r13, regs->r14, regs->r15, regs->r16);
-       printk(KERN_INFO " r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n",
+       pr_info(" r17=%08lX, r18=%08lX, r19=%08lX, r20=%08lX\n",
                                regs->r17, regs->r18, regs->r19, regs->r20);
-       printk(KERN_INFO " r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n",
+       pr_info(" r21=%08lX, r22=%08lX, r23=%08lX, r24=%08lX\n",
                                regs->r21, regs->r22, regs->r23, regs->r24);
-       printk(KERN_INFO " r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n",
+       pr_info(" r25=%08lX, r26=%08lX, r27=%08lX, r28=%08lX\n",
                                regs->r25, regs->r26, regs->r27, regs->r28);
-       printk(KERN_INFO " r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n",
+       pr_info(" r29=%08lX, r30=%08lX, r31=%08lX, rPC=%08lX\n",
                                regs->r29, regs->r30, regs->r31, regs->pc);
-       printk(KERN_INFO " msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n",
+       pr_info(" msr=%08lX, ear=%08lX, esr=%08lX, fsr=%08lX\n",
                                regs->msr, regs->ear, regs->esr, regs->fsr);
 }
 
-void (*pm_idle)(void);
 void (*pm_power_off)(void) = NULL;
 EXPORT_SYMBOL(pm_power_off);
 
 static int hlt_counter = 1;
 
-void disable_hlt(void)
-{
-       hlt_counter++;
-}
-EXPORT_SYMBOL(disable_hlt);
-
-void enable_hlt(void)
-{
-       hlt_counter--;
-}
-EXPORT_SYMBOL(enable_hlt);
-
 static int __init nohlt_setup(char *__unused)
 {
        hlt_counter = 1;
@@ -73,7 +62,13 @@ __setup("hlt", hlt_setup);
 
 void default_idle(void)
 {
-       if (!hlt_counter) {
+       if (likely(hlt_counter)) {
+               local_irq_disable();
+               stop_critical_timings();
+               cpu_relax();
+               start_critical_timings();
+               local_irq_enable();
+       } else {
                clear_thread_flag(TIF_POLLING_NRFLAG);
                smp_mb__after_clear_bit();
                local_irq_disable();
@@ -81,9 +76,7 @@ void default_idle(void)
                        cpu_sleep();
                local_irq_enable();
                set_thread_flag(TIF_POLLING_NRFLAG);
-       } else
-               while (!need_resched())
-                       cpu_relax();
+       }
 }
 
 void cpu_idle(void)
@@ -92,19 +85,14 @@ void cpu_idle(void)
 
        /* endless idle loop with no priority at all */
        while (1) {
-               void (*idle)(void) = pm_idle;
-
-               if (!idle)
-                       idle = default_idle;
-
-               tick_nohz_stop_sched_tick(1);
+               tick_nohz_idle_enter();
+               rcu_idle_enter();
                while (!need_resched())
-                       idle();
-               tick_nohz_restart_sched_tick();
+                       default_idle();
+               rcu_idle_exit();
+               tick_nohz_idle_exit();
 
-               preempt_enable_no_resched();
-               schedule();
-               preempt_disable();
+               schedule_preempt_disabled();
                check_pgt_cache();
        }
 }
@@ -114,46 +102,38 @@ void flush_thread(void)
 }
 
 int copy_thread(unsigned long clone_flags, unsigned long usp,
-               unsigned long unused,
-               struct task_struct *p, struct pt_regs *regs)
+               unsigned long arg, struct task_struct *p)
 {
        struct pt_regs *childregs = task_pt_regs(p);
        struct thread_info *ti = task_thread_info(p);
 
-       *childregs = *regs;
-       if (user_mode(regs))
+       if (unlikely(p->flags & PF_KTHREAD)) {
+               /* if we're creating a new kernel thread then just zeroing all
+                * the registers. That's OK for a brand new thread.*/
+               memset(childregs, 0, sizeof(struct pt_regs));
+               memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
+               ti->cpu_context.r1  = (unsigned long)childregs;
+               ti->cpu_context.r20 = (unsigned long)usp; /* fn */
+               ti->cpu_context.r19 = (unsigned long)arg;
+               childregs->pt_mode = 1;
+               local_save_flags(childregs->msr);
+#ifdef CONFIG_MMU
+               ti->cpu_context.msr = childregs->msr & ~MSR_IE;
+#endif
+               ti->cpu_context.r15 = (unsigned long)ret_from_kernel_thread - 8;
+               return 0;
+       }
+       *childregs = *current_pt_regs();
+       if (usp)
                childregs->r1 = usp;
-       else
-               childregs->r1 = ((unsigned long) ti) + THREAD_SIZE;
 
-#ifndef CONFIG_MMU
        memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
        ti->cpu_context.r1 = (unsigned long)childregs;
+#ifndef CONFIG_MMU
        ti->cpu_context.msr = (unsigned long)childregs->msr;
 #else
+       childregs->msr |= MSR_UMS;
 
-       /* if creating a kernel thread then update the current reg (we don't
-        * want to use the parent's value when restoring by POP_STATE) */
-       if (kernel_mode(regs))
-               /* save new current on stack to use POP_STATE */
-               childregs->CURRENT_TASK = (unsigned long)p;
-       /* if returning to user then use the parent's value of this register */
-
-       /* if we're creating a new kernel thread then just zeroing all
-        * the registers. That's OK for a brand new thread.*/
-       /* Pls. note that some of them will be restored in POP_STATE */
-       if (kernel_mode(regs))
-               memset(&ti->cpu_context, 0, sizeof(struct cpu_context));
-       /* if this thread is created for fork/vfork/clone, then we want to
-        * restore all the parent's context */
-       /* in addition to the registers which will be restored by POP_STATE */
-       else {
-               ti->cpu_context = *(struct cpu_context *)regs;
-               childregs->msr |= MSR_UMS;
-       }
-
-       /* FIXME STATE_SAVE_PT_OFFSET; */
-       ti->cpu_context.r1  = (unsigned long)childregs - STATE_SAVE_ARG_SPACE;
        /* we should consider the fact that childregs is a copy of the parent
         * regs which were saved immediately after entering the kernel state
         * before enabling VM. This MSR will be restored in switch_to and
@@ -164,7 +144,6 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
         * excepting for VM and UMS
         * don't touch UMS , CARRY and cache bits
         * right now MSR is a copy of parent one */
-       childregs->msr |= MSR_BIP;
        childregs->msr &= ~MSR_EIP;
        childregs->msr |= MSR_IE;
        childregs->msr &= ~MSR_VM;
@@ -173,11 +152,16 @@ int copy_thread(unsigned long clone_flags, unsigned long usp,
 
        ti->cpu_context.msr = (childregs->msr|MSR_VM);
        ti->cpu_context.msr &= ~MSR_UMS; /* switch_to to kernel mode */
+       ti->cpu_context.msr &= ~MSR_IE;
 #endif
        ti->cpu_context.r15 = (unsigned long)ret_from_fork - 8;
 
+       /*
+        *  r21 is the thread reg, r10 is 6th arg to clone
+        *  which contains TLS area
+        */
        if (clone_flags & CLONE_SETTLS)
-               ;
+               childregs->r21 = childregs->r10;
 
        return 0;
 }
@@ -199,29 +183,6 @@ unsigned long thread_saved_pc(struct task_struct *tsk)
 }
 #endif
 
-static void kernel_thread_helper(int (*fn)(void *), void *arg)
-{
-       fn(arg);
-       do_exit(-1);
-}
-
-int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags)
-{
-       struct pt_regs regs;
-
-       memset(&regs, 0, sizeof(regs));
-       /* store them in non-volatile registers */
-       regs.r5 = (unsigned long)fn;
-       regs.r6 = (unsigned long)arg;
-       local_save_flags(regs.msr);
-       regs.pc = (unsigned long)kernel_thread_helper;
-       regs.pt_mode = 1;
-
-       return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
-                       &regs, 0, NULL, NULL);
-}
-EXPORT_SYMBOL_GPL(kernel_thread);
-
 unsigned long get_wchan(struct task_struct *p)
 {
 /* TBD (used by procfs) */
@@ -231,12 +192,12 @@ unsigned long get_wchan(struct task_struct *p)
 /* Set up a thread for executing a new program */
 void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long usp)
 {
-       set_fs(USER_DS);
        regs->pc = pc;
        regs->r1 = usp;
        regs->pt_mode = 0;
 #ifdef CONFIG_MMU
        regs->msr |= MSR_UMS;
+       regs->msr &= ~MSR_VM;
 #endif
 }