vserver 2.0 rc7
[linux-2.6.git] / arch / ppc64 / kernel / process.c
index be153b9..cdfecbe 100644 (file)
@@ -34,7 +34,8 @@
 #include <linux/prctl.h>
 #include <linux/ptrace.h>
 #include <linux/kallsyms.h>
-#include <linux/version.h>
+#include <linux/interrupt.h>
+#include <linux/utsname.h>
 
 #include <asm/pgtable.h>
 #include <asm/uaccess.h>
 #include <asm/ppcdebug.h>
 #include <asm/machdep.h>
 #include <asm/iSeries/HvCallHpt.h>
-#include <asm/hardirq.h>
 #include <asm/cputable.h>
 #include <asm/sections.h>
 #include <asm/tlbflush.h>
+#include <asm/time.h>
 
 #ifndef CONFIG_SMP
 struct task_struct *last_task_used_math = NULL;
@@ -65,8 +66,43 @@ struct mm_struct ioremap_mm = {
        .page_table_lock = SPIN_LOCK_UNLOCKED,
 };
 
+/*
+ * Make sure the floating-point register state in the
+ * the thread_struct is up to date for task tsk.
+ */
+void flush_fp_to_thread(struct task_struct *tsk)
+{
+       if (tsk->thread.regs) {
+               /*
+                * We need to disable preemption here because if we didn't,
+                * another process could get scheduled after the regs->msr
+                * test but before we have finished saving the FP registers
+                * to the thread_struct.  That process could take over the
+                * FPU, and then when we get scheduled again we would store
+                * bogus values for the remaining FP registers.
+                */
+               preempt_disable();
+               if (tsk->thread.regs->msr & MSR_FP) {
+#ifdef CONFIG_SMP
+                       /*
+                        * This should only ever be called for current or
+                        * for a stopped child process.  Since we save away
+                        * the FP register state on context switch on SMP,
+                        * there is something wrong if a stopped child appears
+                        * to still have its FP state in the CPU registers.
+                        */
+                       BUG_ON(tsk != current);
+#endif
+                       giveup_fpu(current);
+               }
+               preempt_enable();
+       }
+}
+
 void enable_kernel_fp(void)
 {
+       WARN_ON(preemptible());
+
 #ifdef CONFIG_SMP
        if (current->thread.regs && (current->thread.regs->msr & MSR_FP))
                giveup_fpu(current);
@@ -80,12 +116,9 @@ EXPORT_SYMBOL(enable_kernel_fp);
 
 int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
 {
-       struct pt_regs *regs = tsk->thread.regs;
-
-       if (!regs)
+       if (!tsk->thread.regs)
                return 0;
-       if (tsk == current && (regs->msr & MSR_FP))
-               giveup_fpu(current);
+       flush_fp_to_thread(current);
 
        memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs));
 
@@ -96,6 +129,8 @@ int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs)
 
 void enable_kernel_altivec(void)
 {
+       WARN_ON(preemptible());
+
 #ifdef CONFIG_SMP
        if (current->thread.regs && (current->thread.regs->msr & MSR_VEC))
                giveup_altivec(current);
@@ -107,16 +142,35 @@ void enable_kernel_altivec(void)
 }
 EXPORT_SYMBOL(enable_kernel_altivec);
 
+/*
+ * Make sure the VMX/Altivec register state in the
+ * the thread_struct is up to date for task tsk.
+ */
+void flush_altivec_to_thread(struct task_struct *tsk)
+{
+       if (tsk->thread.regs) {
+               preempt_disable();
+               if (tsk->thread.regs->msr & MSR_VEC) {
+#ifdef CONFIG_SMP
+                       BUG_ON(tsk != current);
+#endif
+                       giveup_altivec(current);
+               }
+               preempt_enable();
+       }
+}
+
 int dump_task_altivec(struct pt_regs *regs, elf_vrregset_t *vrregs)
 {
-       if (regs->msr & MSR_VEC)
-               giveup_altivec(current);
+       flush_altivec_to_thread(current);
        memcpy(vrregs, &current->thread.vr[0], sizeof(*vrregs));
        return 1;
 }
 
 #endif /* CONFIG_ALTIVEC */
 
+DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array);
+
 struct task_struct *__switch_to(struct task_struct *prev,
                                struct task_struct *new)
 {
@@ -155,6 +209,21 @@ struct task_struct *__switch_to(struct task_struct *prev,
        new_thread = &new->thread;
        old_thread = &current->thread;
 
+/* Collect purr utilization data per process and per processor wise */
+/* purr is nothing but processor time base                          */
+
+#if defined(CONFIG_PPC_PSERIES)
+       if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR) {
+               struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array);
+               long unsigned start_tb, current_tb;
+               start_tb = old_thread->start_tb;
+               cu->current_tb = current_tb = mfspr(SPRN_PURR);
+               old_thread->accum_tb += (current_tb - start_tb);
+               new_thread->start_tb = current_tb;
+       }
+#endif
+
+
        local_irq_save(flags);
        last = _switch(old_thread, new_thread);
 
@@ -163,21 +232,57 @@ struct task_struct *__switch_to(struct task_struct *prev,
        return last;
 }
 
+static int instructions_to_print = 16;
+
+static void show_instructions(struct pt_regs *regs)
+{
+       int i;
+       unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 *
+                       sizeof(int));
+
+       printk("Instruction dump:");
+
+       for (i = 0; i < instructions_to_print; i++) {
+               int instr;
+
+               if (!(i % 8))
+                       printk("\n");
+
+               if (((REGION_ID(pc) != KERNEL_REGION_ID) &&
+                    (REGION_ID(pc) != VMALLOC_REGION_ID)) ||
+                    __get_user(instr, (unsigned int *)pc)) {
+                       printk("XXXXXXXX ");
+               } else {
+                       if (regs->nip == pc)
+                               printk("<%08x> ", instr);
+                       else
+                               printk("%08x ", instr);
+               }
+
+               pc += sizeof(int);
+       }
+
+       printk("\n");
+}
+
 void show_regs(struct pt_regs * regs)
 {
        int i;
+       unsigned long trap;
 
-       printk("NIP: %016lX XER: %016lX LR: %016lX\n",
-              regs->nip, regs->xer, regs->link);
+       printk("NIP: %016lX XER: %08X LR: %016lX CTR: %016lX\n",
+              regs->nip, (unsigned int)regs->xer, regs->link, regs->ctr);
        printk("REGS: %p TRAP: %04lx   %s  (%s)\n",
-              regs, regs->trap, print_tainted(), UTS_RELEASE);
-       printk("MSR: %016lx EE: %01x PR: %01x FP: %01x ME: %01x IR/DR: %01x%01x\n",
+              regs, regs->trap, print_tainted(), system_utsname.release);
+       printk("MSR: %016lx EE: %01x PR: %01x FP: %01x ME: %01x "
+              "IR/DR: %01x%01x CR: %08X\n",
               regs->msr, regs->msr&MSR_EE ? 1 : 0, regs->msr&MSR_PR ? 1 : 0,
               regs->msr & MSR_FP ? 1 : 0,regs->msr&MSR_ME ? 1 : 0,
               regs->msr&MSR_IR ? 1 : 0,
-              regs->msr&MSR_DR ? 1 : 0);
-       if (regs->trap == 0x300 || regs->trap == 0x380 || regs->trap == 0x600)
-               printk("DAR: %016lx, DSISR: %016lx\n", regs->dar, regs->dsisr);
+              regs->msr&MSR_DR ? 1 : 0,
+              (unsigned int)regs->ccr);
+       trap = TRAP(regs);
+       printk("DAR: %016lx DSISR: %016lx\n", regs->dar, regs->dsisr);
        printk("TASK: %p[%d] '%s' THREAD: %p",
               current, current->pid, current->comm, current->thread_info);
 
@@ -191,6 +296,8 @@ void show_regs(struct pt_regs * regs)
                }
 
                printk("%016lX ", regs->gpr[i]);
+               if (i == 13 && !FULL_REGS(regs))
+                       break;
        }
        printk("\n");
        /*
@@ -202,6 +309,8 @@ void show_regs(struct pt_regs * regs)
        printk("LR [%016lx] ", regs->link);
        print_symbol("%s\n", regs->link);
        show_stack(current, (unsigned long *)regs->gpr[1]);
+       if (!user_mode(regs))
+               show_instructions(regs);
 }
 
 void exit_thread(void)
@@ -245,16 +354,8 @@ release_thread(struct task_struct *t)
  */
 void prepare_to_copy(struct task_struct *tsk)
 {
-       struct pt_regs *regs = tsk->thread.regs;
-
-       if (regs == NULL)
-               return;
-       if (regs->msr & MSR_FP)
-               giveup_fpu(current);
-#ifdef CONFIG_ALTIVEC
-       if (regs->msr & MSR_VEC)
-               giveup_altivec(current);
-#endif /* CONFIG_ALTIVEC */
+       flush_fp_to_thread(current);
+       flush_altivec_to_thread(current);
 }
 
 /*
@@ -268,8 +369,6 @@ copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
        extern void ret_from_fork(void);
        unsigned long sp = (unsigned long)p->thread_info + THREAD_SIZE;
 
-       p->set_child_tid = p->clear_child_tid = NULL;
-
        /* Copy registers */
        sp -= sizeof(struct pt_regs);
        childregs = (struct pt_regs *) sp;
@@ -279,9 +378,6 @@ copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
                childregs->gpr[1] = sp + sizeof(struct pt_regs);
                p->thread.regs = NULL;  /* no user register state */
                clear_ti_thread_flag(p->thread_info, TIF_32BIT);
-#ifdef CONFIG_PPC_ISERIES
-               set_ti_thread_flag(p->thread_info, TIF_RUN_LIGHT);
-#endif
        } else {
                childregs->gpr[1] = usp;
                p->thread.regs = childregs;
@@ -307,6 +403,16 @@ copy_thread(int nr, unsigned long clone_flags, unsigned long usp,
        kregs = (struct pt_regs *) sp;
        sp -= STACK_FRAME_OVERHEAD;
        p->thread.ksp = sp;
+       if (cpu_has_feature(CPU_FTR_SLB)) {
+               unsigned long sp_vsid = get_kernel_vsid(sp);
+
+               sp_vsid <<= SLB_VSID_SHIFT;
+               sp_vsid |= SLB_VSID_KERNEL;
+               if (cpu_has_feature(CPU_FTR_16M_PAGE))
+                       sp_vsid |= SLB_VSID_L;
+
+               p->thread.ksp_vsid = sp_vsid;
+       }
 
        /*
         * The PPC64 ABI makes use of a TOC to contain function 
@@ -338,11 +444,22 @@ void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp)
        /* Check whether the e_entry function descriptor entries
         * need to be relocated before we can use them.
         */
-       if ( load_addr != 0 ) {
+       if (load_addr != 0) {
                entry += load_addr;
                toc   += load_addr;
        }
 
+       /*
+        * If we exec out of a kernel thread then thread.regs will not be
+        * set. Do it now.
+        */
+       if (!current->thread.regs) {
+               unsigned long childregs = (unsigned long)current->thread_info +
+                                               THREAD_SIZE;
+               childregs -= sizeof(struct pt_regs);
+               current->thread.regs = (struct pt_regs *)childregs;
+       }
+
        regs->nip = entry;
        regs->gpr[1] = sp;
        regs->gpr[2] = toc;
@@ -367,6 +484,7 @@ void start_thread(struct pt_regs *regs, unsigned long fdptr, unsigned long sp)
        current->thread.used_vr = 0;
 #endif /* CONFIG_ALTIVEC */
 }
+EXPORT_SYMBOL(start_thread);
 
 int set_fpexc_mode(struct task_struct *tsk, unsigned int val)
 {
@@ -409,7 +527,7 @@ int sys_clone(unsigned long clone_flags, unsigned long p2, unsigned long p3,
                }
        }
 
-       return do_fork(clone_flags & ~CLONE_IDLETASK, p2, regs, 0,
+       return do_fork(clone_flags, p2, regs, 0,
                    (int __user *)parent_tidptr, (int __user *)child_tidptr);
 }
 
@@ -439,17 +557,16 @@ int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2,
        error = PTR_ERR(filename);
        if (IS_ERR(filename))
                goto out;
-       if (regs->msr & MSR_FP)
-               giveup_fpu(current);
-#ifdef CONFIG_ALTIVEC
-       if (regs->msr & MSR_VEC)
-               giveup_altivec(current);
-#endif /* CONFIG_ALTIVEC */
+       flush_fp_to_thread(current);
+       flush_altivec_to_thread(current);
        error = do_execve(filename, (char __user * __user *) a1,
                                    (char __user * __user *) a2, regs);
   
-       if (error == 0)
+       if (error == 0) {
+               task_lock(current);
                current->ptrace &= ~PT_DTRACE;
+               task_unlock(current);
+       }
        putname(filename);
 
 out:
@@ -506,6 +623,7 @@ unsigned long get_wchan(struct task_struct *p)
        } while (count++ < 16);
        return 0;
 }
+EXPORT_SYMBOL(get_wchan);
 
 void show_stack(struct task_struct *p, unsigned long *_sp)
 {