diff options
| -rw-r--r-- | arch/tile/include/asm/processor.h | 2 | ||||
| -rw-r--r-- | arch/tile/include/asm/thread_info.h | 8 | ||||
| -rw-r--r-- | arch/tile/kernel/intvec_32.S | 46 | ||||
| -rw-r--r-- | arch/tile/kernel/intvec_64.S | 49 | ||||
| -rw-r--r-- | arch/tile/kernel/process.c | 79 |
5 files changed, 77 insertions, 107 deletions
diff --git a/arch/tile/include/asm/processor.h b/arch/tile/include/asm/processor.h index 139dfdee0134..0684e88aacd8 100644 --- a/arch/tile/include/asm/processor.h +++ b/arch/tile/include/asm/processor.h @@ -212,7 +212,7 @@ static inline void release_thread(struct task_struct *dead_task) /* Nothing for now */ } -extern int do_work_pending(struct pt_regs *regs, u32 flags); +extern void prepare_exit_to_usermode(struct pt_regs *regs, u32 flags); /* diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h index dc1fb28d9636..4b7cef9e94e0 100644 --- a/arch/tile/include/asm/thread_info.h +++ b/arch/tile/include/asm/thread_info.h @@ -140,10 +140,14 @@ extern void _cpu_idle(void); #define _TIF_POLLING_NRFLAG (1<<TIF_POLLING_NRFLAG) #define _TIF_NOHZ (1<<TIF_NOHZ) +/* Work to do as we loop to exit to user space. */ +#define _TIF_WORK_MASK \ + (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ + _TIF_ASYNC_TLB | _TIF_NOTIFY_RESUME) + /* Work to do on any return to user space. */ #define _TIF_ALLWORK_MASK \ - (_TIF_SIGPENDING | _TIF_NEED_RESCHED | _TIF_SINGLESTEP | \ - _TIF_ASYNC_TLB | _TIF_NOTIFY_RESUME | _TIF_NOHZ) + (_TIF_WORK_MASK | _TIF_SINGLESTEP | _TIF_NOHZ) /* Work to do at syscall entry. */ #define _TIF_SYSCALL_ENTRY_WORK \ diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S index fbbe2ea882ea..33d48812872a 100644 --- a/arch/tile/kernel/intvec_32.S +++ b/arch/tile/kernel/intvec_32.S @@ -846,18 +846,6 @@ STD_ENTRY(interrupt_return) FEEDBACK_REENTER(interrupt_return) /* - * Use r33 to hold whether we have already loaded the callee-saves - * into ptregs. We don't want to do it twice in this loop, since - * then we'd clobber whatever changes are made by ptrace, etc. - * Get base of stack in r32. - */ - { - GET_THREAD_INFO(r32) - movei r33, 0 - } - -.Lretry_work_pending: - /* * Disable interrupts so as to make sure we don't * miss an interrupt that sets any of the thread flags (like * need_resched or sigpending) between sampling and the iret. @@ -867,33 +855,27 @@ STD_ENTRY(interrupt_return) IRQ_DISABLE(r20, r21) TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */ - - /* Check to see if there is any work to do before returning to user. */ + /* + * See if there are any work items (including single-shot items) + * to do. If so, save the callee-save registers to pt_regs + * and then dispatch to C code. + */ + GET_THREAD_INFO(r21) { - addi r29, r32, THREAD_INFO_FLAGS_OFFSET - moveli r1, lo16(_TIF_ALLWORK_MASK) + addi r22, r21, THREAD_INFO_FLAGS_OFFSET + moveli r20, lo16(_TIF_ALLWORK_MASK) } { - lw r29, r29 - auli r1, r1, ha16(_TIF_ALLWORK_MASK) + lw r22, r22 + auli r20, r20, ha16(_TIF_ALLWORK_MASK) } - and r1, r29, r1 - bzt r1, .Lrestore_all - - /* - * Make sure we have all the registers saved for signal - * handling, notify-resume, or single-step. Call out to C - * code to figure out exactly what we need to do for each flag bit, - * then if necessary, reload the flags and recheck. - */ + and r1, r22, r20 { PTREGS_PTR(r0, PTREGS_OFFSET_BASE) - bnz r33, 1f + bzt r1, .Lrestore_all } push_extra_callee_saves r0 - movei r33, 1 -1: jal do_work_pending - bnz r0, .Lretry_work_pending + jal prepare_exit_to_usermode /* * In the NMI case we @@ -1327,7 +1309,7 @@ STD_ENTRY(ret_from_kernel_thread) FEEDBACK_REENTER(ret_from_kernel_thread) { movei r30, 0 /* not an NMI */ - j .Lresume_userspace /* jump into middle of interrupt_return */ + j interrupt_return } STD_ENDPROC(ret_from_kernel_thread) diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S index 58964d209d4d..a41c994ce237 100644 --- a/arch/tile/kernel/intvec_64.S +++ b/arch/tile/kernel/intvec_64.S @@ -879,20 +879,6 @@ STD_ENTRY(interrupt_return) FEEDBACK_REENTER(interrupt_return) /* - * Use r33 to hold whether we have already loaded the callee-saves - * into ptregs. We don't want to do it twice in this loop, since - * then we'd clobber whatever changes are made by ptrace, etc. - */ - { - movei r33, 0 - move r32, sp - } - - /* Get base of stack in r32. */ - EXTRACT_THREAD_INFO(r32) - -.Lretry_work_pending: - /* * Disable interrupts so as to make sure we don't * miss an interrupt that sets any of the thread flags (like * need_resched or sigpending) between sampling and the iret. @@ -902,33 +888,28 @@ STD_ENTRY(interrupt_return) IRQ_DISABLE(r20, r21) TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */ - - /* Check to see if there is any work to do before returning to user. */ + /* + * See if there are any work items (including single-shot items) + * to do. If so, save the callee-save registers to pt_regs + * and then dispatch to C code. + */ + move r21, sp + EXTRACT_THREAD_INFO(r21) { - addi r29, r32, THREAD_INFO_FLAGS_OFFSET - moveli r1, hw1_last(_TIF_ALLWORK_MASK) + addi r22, r21, THREAD_INFO_FLAGS_OFFSET + moveli r20, hw1_last(_TIF_ALLWORK_MASK) } { - ld r29, r29 - shl16insli r1, r1, hw0(_TIF_ALLWORK_MASK) + ld r22, r22 + shl16insli r20, r20, hw0(_TIF_ALLWORK_MASK) } - and r1, r29, r1 - beqzt r1, .Lrestore_all - - /* - * Make sure we have all the registers saved for signal - * handling or notify-resume. Call out to C code to figure out - * exactly what we need to do for each flag bit, then if - * necessary, reload the flags and recheck. - */ + and r1, r22, r20 { PTREGS_PTR(r0, PTREGS_OFFSET_BASE) - bnez r33, 1f + beqzt r1, .Lrestore_all } push_extra_callee_saves r0 - movei r33, 1 -1: jal do_work_pending - bnez r0, .Lretry_work_pending + jal prepare_exit_to_usermode /* * In the NMI case we @@ -1411,7 +1392,7 @@ STD_ENTRY(ret_from_kernel_thread) FEEDBACK_REENTER(ret_from_kernel_thread) { movei r30, 0 /* not an NMI */ - j .Lresume_userspace /* jump into middle of interrupt_return */ + j interrupt_return } STD_ENDPROC(ret_from_kernel_thread) diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 7d5769310bef..b5f30d376ce1 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -462,54 +462,57 @@ struct task_struct *__sched _switch_to(struct task_struct *prev, /* * This routine is called on return from interrupt if any of the - * TIF_WORK_MASK flags are set in thread_info->flags. It is - * entered with interrupts disabled so we don't miss an event - * that modified the thread_info flags. If any flag is set, we - * handle it and return, and the calling assembly code will - * re-disable interrupts, reload the thread flags, and call back - * if more flags need to be handled. - * - * We return whether we need to check the thread_info flags again - * or not. Note that we don't clear TIF_SINGLESTEP here, so it's - * important that it be tested last, and then claim that we don't - * need to recheck the flags. + * TIF_ALLWORK_MASK flags are set in thread_info->flags. It is + * entered with interrupts disabled so we don't miss an event that + * modified the thread_info flags. We loop until all the tested flags + * are clear. Note that the function is called on certain conditions + * that are not listed in the loop condition here (e.g. SINGLESTEP) + * which guarantees we will do those things once, and redo them if any + * of the other work items is re-done, but won't continue looping if + * all the other work is done. */ -int do_work_pending(struct pt_regs *regs, u32 thread_info_flags) +void prepare_exit_to_usermode(struct pt_regs *regs, u32 thread_info_flags) { - /* If we enter in kernel mode, do nothing and exit the caller loop. */ - if (!user_mode(regs)) - return 0; + if (WARN_ON(!user_mode(regs))) + return; - user_exit(); + do { + local_irq_enable(); - /* Enable interrupts; they are disabled again on return to caller. */ - local_irq_enable(); + if (thread_info_flags & _TIF_NEED_RESCHED) + schedule(); - if (thread_info_flags & _TIF_NEED_RESCHED) { - schedule(); - return 1; - } #if CHIP_HAS_TILE_DMA() - if (thread_info_flags & _TIF_ASYNC_TLB) { - do_async_page_fault(regs); - return 1; - } + if (thread_info_flags & _TIF_ASYNC_TLB) + do_async_page_fault(regs); #endif - if (thread_info_flags & _TIF_SIGPENDING) { - do_signal(regs); - return 1; - } - if (thread_info_flags & _TIF_NOTIFY_RESUME) { - clear_thread_flag(TIF_NOTIFY_RESUME); - tracehook_notify_resume(regs); - return 1; - } - if (thread_info_flags & _TIF_SINGLESTEP) + + if (thread_info_flags & _TIF_SIGPENDING) + do_signal(regs); + + if (thread_info_flags & _TIF_NOTIFY_RESUME) { + clear_thread_flag(TIF_NOTIFY_RESUME); + tracehook_notify_resume(regs); + } + + local_irq_disable(); + thread_info_flags = READ_ONCE(current_thread_info()->flags); + + } while (thread_info_flags & _TIF_WORK_MASK); + + if (thread_info_flags & _TIF_SINGLESTEP) { single_step_once(regs); +#ifndef __tilegx__ + /* + * FIXME: on tilepro, since we enable interrupts in + * this routine, it's possible that we miss a signal + * or other asynchronous event. + */ + local_irq_disable(); +#endif + } user_enter(); - - return 0; } unsigned long get_wchan(struct task_struct *p) |