[MIPS] MT: Improved multithreading support.

[deliverable/linux.git] / arch / mips / kernel / ptrace.c

diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c
index f838b36cc765bcbc9ad544701aec14e2ff29c278..f3106d0771b0707ba21a767c32ed852530bc78d9 100644 (file)
--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -248,10 +248,20 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                        break;
                case FPC_EIR: { /* implementation / version register */
                        unsigned int flags;
+#ifdef CONFIG_MIPS_MT_SMTC
+                       unsigned int irqflags;
+                       unsigned int mtflags;
+#endif /* CONFIG_MIPS_MT_SMTC */
 
                        if (!cpu_has_fpu)
                                break;
 
+#ifdef CONFIG_MIPS_MT_SMTC
+                       /* Read-modify-write of Status must be atomic */
+                       local_irq_save(irqflags);
+                       mtflags = dmt();
+#endif /* CONFIG_MIPS_MT_SMTC */
+
                        preempt_disable();
                        if (cpu_has_mipsmt) {
                                unsigned int vpflags = dvpe();
@@ -266,6 +276,10 @@ long arch_ptrace(struct task_struct *child, long request, long addr, long data)
                                __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
                                write_c0_status(flags);
                        }
+#ifdef CONFIG_MIPS_MT_SMTC
+                       emt(mtflags);
+                       local_irq_restore(irqflags);
+#endif /* CONFIG_MIPS_MT_SMTC */
                        preempt_enable();
                        break;
                }