diff options
Diffstat (limited to 'arch/tile')
| -rw-r--r-- | arch/tile/include/asm/thread_info.h | 9 | ||||
| -rw-r--r-- | arch/tile/kernel/intvec_32.S | 41 | ||||
| -rw-r--r-- | arch/tile/kernel/intvec_64.S | 38 | ||||
| -rw-r--r-- | arch/tile/kernel/process.c | 7 |
4 files changed, 68 insertions, 27 deletions
diff --git a/arch/tile/include/asm/thread_info.h b/arch/tile/include/asm/thread_info.h index bc4f562bd45..7594764d8a6 100644 --- a/arch/tile/include/asm/thread_info.h +++ b/arch/tile/include/asm/thread_info.h @@ -100,9 +100,14 @@ extern void cpu_idle_on_new_stack(struct thread_info *old_ti, #else /* __ASSEMBLY__ */ -/* how to get the thread information struct from ASM */ +/* + * How to get the thread information struct from assembly. + * Note that we use different macros since different architectures + * have different semantics in their "mm" instruction and we would + * like to guarantee that the macro expands to exactly one instruction. + */ #ifdef __tilegx__ -#define GET_THREAD_INFO(reg) move reg, sp; mm reg, zero, LOG2_THREAD_SIZE, 63 +#define EXTRACT_THREAD_INFO(reg) mm reg, zero, LOG2_THREAD_SIZE, 63 #else #define GET_THREAD_INFO(reg) mm reg, sp, zero, LOG2_THREAD_SIZE, 31 #endif diff --git a/arch/tile/kernel/intvec_32.S b/arch/tile/kernel/intvec_32.S index 5d56a1ef5ba..6943515100f 100644 --- a/arch/tile/kernel/intvec_32.S +++ b/arch/tile/kernel/intvec_32.S @@ -839,6 +839,18 @@ 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. @@ -848,9 +860,6 @@ STD_ENTRY(interrupt_return) IRQ_DISABLE(r20, r21) TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */ - /* Get base of stack in r32; note r30/31 are used as arguments here. */ - GET_THREAD_INFO(r32) - /* Check to see if there is any work to do before returning to user. */ { @@ -866,16 +875,18 @@ STD_ENTRY(interrupt_return) /* * Make sure we have all the registers saved for signal - * handling 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. + * 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. */ - push_extra_callee_saves r0 { PTREGS_PTR(r0, PTREGS_OFFSET_BASE) - jal do_work_pending + bnz r33, 1f } - bnz r0, .Lresume_userspace + push_extra_callee_saves r0 + movei r33, 1 +1: jal do_work_pending + bnz r0, .Lretry_work_pending /* * In the NMI case we @@ -1180,10 +1191,12 @@ handle_syscall: add r20, r20, tp lw r21, r20 addi r21, r21, 1 - sw r20, r21 + { + sw r20, r21 + GET_THREAD_INFO(r31) + } /* Trace syscalls, if requested. */ - GET_THREAD_INFO(r31) addi r31, r31, THREAD_INFO_FLAGS_OFFSET lw r30, r31 andi r30, r30, _TIF_SYSCALL_TRACE @@ -1362,7 +1375,10 @@ handle_ill: 3: /* set PC and continue */ lw r26, r24 - sw r28, r26 + { + sw r28, r26 + GET_THREAD_INFO(r0) + } /* * Clear TIF_SINGLESTEP to prevent recursion if we execute an ill. @@ -1370,7 +1386,6 @@ handle_ill: * need to clear it here and can't really impose on all other arches. * So what's another write between friends? */ - GET_THREAD_INFO(r0) addi r1, r0, THREAD_INFO_FLAGS_OFFSET { diff --git a/arch/tile/kernel/intvec_64.S b/arch/tile/kernel/intvec_64.S index 49d9d662168..30ae76e50c4 100644 --- a/arch/tile/kernel/intvec_64.S +++ b/arch/tile/kernel/intvec_64.S @@ -647,6 +647,20 @@ 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. @@ -656,9 +670,6 @@ STD_ENTRY(interrupt_return) IRQ_DISABLE(r20, r21) TRACE_IRQS_OFF /* Note: clobbers registers r0-r29 */ - /* Get base of stack in r32; note r30/31 are used as arguments here. */ - GET_THREAD_INFO(r32) - /* Check to see if there is any work to do before returning to user. */ { @@ -674,16 +685,18 @@ STD_ENTRY(interrupt_return) /* * Make sure we have all the registers saved for signal - * handling or single-step. Call out to C code to figure out + * 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. */ - push_extra_callee_saves r0 { PTREGS_PTR(r0, PTREGS_OFFSET_BASE) - jal do_work_pending + bnez r33, 1f } - bnez r0, .Lresume_userspace + push_extra_callee_saves r0 + movei r33, 1 +1: jal do_work_pending + bnez r0, .Lretry_work_pending /* * In the NMI case we @@ -968,11 +981,16 @@ handle_syscall: shl16insli r20, r20, hw0(irq_stat + IRQ_CPUSTAT_SYSCALL_COUNT_OFFSET) add r20, r20, tp ld4s r21, r20 - addi r21, r21, 1 - st4 r20, r21 + { + addi r21, r21, 1 + move r31, sp + } + { + st4 r20, r21 + EXTRACT_THREAD_INFO(r31) + } /* Trace syscalls, if requested. */ - GET_THREAD_INFO(r31) addi r31, r31, THREAD_INFO_FLAGS_OFFSET ld r30, r31 andi r30, r30, _TIF_SYSCALL_TRACE diff --git a/arch/tile/kernel/process.c b/arch/tile/kernel/process.c index 2d5ef617bb3..54e6c64b85c 100644 --- a/arch/tile/kernel/process.c +++ b/arch/tile/kernel/process.c @@ -567,6 +567,10 @@ struct task_struct *__sched _switch_to(struct task_struct *prev, */ int do_work_pending(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 (thread_info_flags & _TIF_NEED_RESCHED) { schedule(); return 1; @@ -589,8 +593,7 @@ int do_work_pending(struct pt_regs *regs, u32 thread_info_flags) return 1; } if (thread_info_flags & _TIF_SINGLESTEP) { - if ((regs->ex1 & SPR_EX_CONTEXT_1_1__PL_MASK) == 0) - single_step_once(regs); + single_step_once(regs); return 0; } panic("work_pending: bad flags %#x\n", thread_info_flags); |