diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index b3e0cfcc84f6..c07c31b0e89e 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -257,6 +257,7 @@ struct thread_struct { int used_spe; /* set if process has used spe */ #endif /* CONFIG_SPE */ #ifdef CONFIG_PPC_TRANSACTIONAL_MEM + u8 load_tm; u64 tm_tfhar; /* Transaction fail handler addr */ u64 tm_texasr; /* Transaction exception & summary */ u64 tm_tfiar; /* Transaction fail instr address reg */ diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c index e22033005d15..9e7c10fe205f 100644 --- a/arch/powerpc/kernel/process.c +++ b/arch/powerpc/kernel/process.c @@ -812,6 +812,12 @@ static inline bool hw_brk_match(struct arch_hw_breakpoint *a, } #ifdef CONFIG_PPC_TRANSACTIONAL_MEM + +static inline bool tm_enabled(struct task_struct *tsk) +{ + return tsk && tsk->thread.regs && (tsk->thread.regs->msr & MSR_TM); +} + static void tm_reclaim_thread(struct thread_struct *thr, struct thread_info *ti, uint8_t cause) { @@ -892,6 +898,9 @@ void tm_recheckpoint(struct thread_struct *thread, { unsigned long flags; + if (!(thread->regs->msr & MSR_TM)) + return; + /* 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. @@ -924,7 +933,7 @@ static inline void tm_recheckpoint_new_task(struct task_struct *new) * unavailable later, we are unable to determine which set of FP regs * need to be restored. */ - if (!new->thread.regs) + if (!tm_enabled(new)) return; if (!MSR_TM_ACTIVE(new->thread.regs->msr)){ @@ -955,8 +964,16 @@ static inline void __switch_to_tm(struct task_struct *prev, struct task_struct *new) { if (cpu_has_feature(CPU_FTR_TM)) { - tm_enable(); - tm_reclaim_task(prev); + if (tm_enabled(prev) || tm_enabled(new)) + tm_enable(); + + if (tm_enabled(prev)) { + prev->thread.load_tm++; + tm_reclaim_task(prev); + if (!MSR_TM_ACTIVE(prev->thread.regs->msr) && prev->thread.load_tm == 0) + prev->thread.regs->msr &= ~MSR_TM; + } + tm_recheckpoint_new_task(new); } } @@ -1393,6 +1410,9 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) * 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. + * + * Can't pass dst because it isn't ready. Doesn't matter, passing + * dst is only important for __switch_to() */ __switch_to_tm(src, src); @@ -1636,8 +1656,6 @@ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) current->thread.used_spe = 0; #endif /* CONFIG_SPE */ #ifdef CONFIG_PPC_TRANSACTIONAL_MEM - if (cpu_has_feature(CPU_FTR_TM)) - regs->msr |= MSR_TM; current->thread.tm_tfhar = 0; current->thread.tm_texasr = 0; current->thread.tm_tfiar = 0; diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c index 2f5ef5a80353..a1f8f5641e9e 100644 --- a/arch/powerpc/kernel/traps.c +++ b/arch/powerpc/kernel/traps.c @@ -1392,6 +1392,15 @@ void vsx_unavailable_exception(struct pt_regs *regs) #ifdef CONFIG_PPC64 static void tm_unavailable(struct pt_regs *regs) { +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM + if (user_mode(regs)) { + current->thread.load_tm++; + regs->msr |= MSR_TM; + tm_enable(); + tm_restore_sprs(¤t->thread); + return; + } +#endif pr_emerg("Unrecoverable TM Unavailable Exception " "%lx at %lx\n", regs->trap, regs->nip); die("Unrecoverable TM Unavailable Exception", regs, SIGABRT);