diff options
Diffstat (limited to 'arch/powerpc/kernel/process.c')
-rw-r--r-- | arch/powerpc/kernel/process.c | 54 |
1 files changed, 48 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index 076d1242507a..d55357ee9028 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -523,6 +523,31 @@ out_and_saveregs: tm_save_sprs(thr); } +extern void __tm_recheckpoint(struct thread_struct *thread, + unsigned long orig_msr); + +void tm_recheckpoint(struct thread_struct *thread, + unsigned long orig_msr) +{ + unsigned long flags; + + /* We really can't be interrupted here as the TEXASR registers can't + * change and later in the trecheckpoint code, we have a userspace R1. + * So let's hard disable over this region. + */ + local_irq_save(flags); + hard_irq_disable(); + + /* The TM SPRs are restored here, so that TEXASR.FS can be set + * before the trecheckpoint and no explosion occurs. + */ + tm_restore_sprs(thread); + + __tm_recheckpoint(thread, orig_msr); + + local_irq_restore(flags); +} + static inline void tm_recheckpoint_new_task(struct task_struct *new) { unsigned long msr; @@ -541,13 +566,10 @@ static inline void tm_recheckpoint_new_task(struct task_struct *new) if (!new->thread.regs) return; - /* The TM SPRs are restored here, so that TEXASR.FS can be set - * before the trecheckpoint and no explosion occurs. - */ - tm_restore_sprs(&new->thread); - - if (!MSR_TM_ACTIVE(new->thread.regs->msr)) + if (!MSR_TM_ACTIVE(new->thread.regs->msr)){ + tm_restore_sprs(&new->thread); return; + } msr = new->thread.tm_orig_msr; /* Recheckpoint to restore original checkpointed register state. */ TM_DEBUG("*** tm_recheckpoint of pid %d " @@ -600,6 +622,16 @@ struct task_struct *__switch_to(struct task_struct *prev, struct ppc64_tlb_batch *batch; #endif + /* Back up the TAR across context switches. + * Note that the TAR is not available for use in the kernel. (To + * provide this, the TAR should be backed up/restored on exception + * entry/exit instead, and be in pt_regs. FIXME, this should be in + * pt_regs anyway (for debug).) + * Save the TAR here before we do treclaim/trecheckpoint as these + * will change the TAR. + */ + save_tar(&prev->thread); + __switch_to_tm(prev); #ifdef CONFIG_SMP @@ -916,6 +948,16 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) flush_altivec_to_thread(src); flush_vsx_to_thread(src); flush_spe_to_thread(src); + /* + * Flush TM state out so we can copy it. __switch_to_tm() does this + * flush but it removes the checkpointed state from the current CPU and + * transitions the CPU out of TM mode. Hence we need to call + * tm_recheckpoint_new_task() (on the same task) to restore the + * checkpointed state back and the TM mode. + */ + __switch_to_tm(src); + tm_recheckpoint_new_task(src); + *dst = *src; return 0; } |