| Message ID | 20210130130852.2952424-43-npiggin@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | powerpc: interrupt wrappers | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (44158b256b30415079588d0fcb1bccbdc2ccd009) |
| snowpatch_ozlabs/build-ppc64le | success | Build succeeded and removed 5 sparse warnings |
| snowpatch_ozlabs/build-ppc64be | success | Build succeeded and removed 5 sparse warnings |
| snowpatch_ozlabs/build-ppc64e | success | Build succeeded and removed 1 sparse warnings |
| snowpatch_ozlabs/build-pmac32 | success | Build succeeded |
| snowpatch_ozlabs/checkpatch | warning | total: 0 errors, 1 warnings, 0 checks, 165 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
Nicholas Piggin <npiggin@gmail.com> writes: > There is no need for this to be in asm, use the new intrrupt entry wrapper. > > Signed-off-by: Nicholas Piggin <npiggin@gmail.com> > --- > arch/powerpc/include/asm/interrupt.h | 15 +++++++++ > arch/powerpc/include/asm/processor.h | 1 + > arch/powerpc/include/asm/thread_info.h | 6 ++++ > arch/powerpc/kernel/exceptions-64s.S | 45 -------------------------- > arch/powerpc/kernel/idle_book3s.S | 4 +++ > 5 files changed, 26 insertions(+), 45 deletions(-) Something in here is making my G5 not boot. I don't know what the problem is because that machine is in the office, and I am not, and it has no serial console. I tried turning on pstore but it doesn't record anything :/ cheers
Excerpts from Michael Ellerman's message of February 2, 2021 8:31 pm: > Nicholas Piggin <npiggin@gmail.com> writes: >> There is no need for this to be in asm, use the new intrrupt entry wrapper. >> >> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> >> --- >> arch/powerpc/include/asm/interrupt.h | 15 +++++++++ >> arch/powerpc/include/asm/processor.h | 1 + >> arch/powerpc/include/asm/thread_info.h | 6 ++++ >> arch/powerpc/kernel/exceptions-64s.S | 45 -------------------------- >> arch/powerpc/kernel/idle_book3s.S | 4 +++ >> 5 files changed, 26 insertions(+), 45 deletions(-) > > Something in here is making my G5 not boot. > > I don't know what the problem is because that machine is in the office, > and I am not, and it has no serial console. I'll try it in qemu again, haven't tested that for a few rebases. You can just drop this for now. Thanks, Nick
Excerpts from Michael Ellerman's message of February 2, 2021 8:31 pm: > Nicholas Piggin <npiggin@gmail.com> writes: >> There is no need for this to be in asm, use the new intrrupt entry wrapper. >> >> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> >> --- >> arch/powerpc/include/asm/interrupt.h | 15 +++++++++ >> arch/powerpc/include/asm/processor.h | 1 + >> arch/powerpc/include/asm/thread_info.h | 6 ++++ >> arch/powerpc/kernel/exceptions-64s.S | 45 -------------------------- >> arch/powerpc/kernel/idle_book3s.S | 4 +++ >> 5 files changed, 26 insertions(+), 45 deletions(-) > > Something in here is making my G5 not boot. > > I don't know what the problem is because that machine is in the office, > and I am not, and it has no serial console. > > I tried turning on pstore but it doesn't record anything :/ Here is an incremental patch (hopefully) should fix it. Should be folded with this one. Thanks, Nick --- powerpc/64s: nap_adjust_return fix This is a fix for patch "powerpc/64s: power4 nap fixup in C". Non-maskable interrupts should not create any exit work, so there should be no reason to come out of idle. So take the nap fixup out of NMIs. The problem with having them here is that an interrupt can come in and then get interrupted by an NMI, the NMI will then set its return to the idle wakeup and never complete the regular interrupt handling. Before the "powerpc/64s: power4 nap fixup in C" patch, this wouldn't occur because the true NMIs didn't call FIXUP_NAP, and the other interrupts would call it before running their handler, so they would not have a chance to call may_hard_irq_enable and allow soft-NMIs (watchdog, perf) to come through. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/include/asm/interrupt.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 25f2420b1965..afdf4aba2e6b 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -12,6 +12,7 @@ static inline void nap_adjust_return(struct pt_regs *regs) { #ifdef CONFIG_PPC_970_NAP if (unlikely(test_thread_local_flags(_TLF_NAPPING))) { + /* Can avoid a test-and-clear because NMIs do not call this */ clear_thread_local_flags(_TLF_NAPPING); regs->nip = (unsigned long)power4_idle_nap_return; } @@ -164,7 +165,10 @@ static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct inter radix_enabled() || (mfmsr() & MSR_DR)) nmi_exit(); - nap_adjust_return(regs); + /* + * nmi does not call nap_adjust_return because nmi should not create + * new work to do (must use irq_work for that). + */ #ifdef CONFIG_PPC64 if (TRAP(regs) != 0x900 && TRAP(regs) != 0xf00 && TRAP(regs) != 0x260)
diff --git a/arch/powerpc/include/asm/interrupt.h b/arch/powerpc/include/asm/interrupt.h index 4badb3e51c19..25f2420b1965 100644 --- a/arch/powerpc/include/asm/interrupt.h +++ b/arch/powerpc/include/asm/interrupt.h @@ -8,6 +8,16 @@ #include <asm/ftrace.h> #include <asm/runlatch.h> +static inline void nap_adjust_return(struct pt_regs *regs) +{ +#ifdef CONFIG_PPC_970_NAP + if (unlikely(test_thread_local_flags(_TLF_NAPPING))) { + clear_thread_local_flags(_TLF_NAPPING); + regs->nip = (unsigned long)power4_idle_nap_return; + } +#endif +} + struct interrupt_state { #ifdef CONFIG_PPC_BOOK3E_64 enum ctx_state ctx_state; @@ -98,6 +108,9 @@ static inline void interrupt_async_exit_prepare(struct pt_regs *regs, struct int { irq_exit(); interrupt_exit_prepare(regs, state); + + /* Adjust at exit so the main handler sees the true NIA */ + nap_adjust_return(regs); } struct interrupt_nmi_state { @@ -151,6 +164,8 @@ static inline void interrupt_nmi_exit_prepare(struct pt_regs *regs, struct inter radix_enabled() || (mfmsr() & MSR_DR)) nmi_exit(); + nap_adjust_return(regs); + #ifdef CONFIG_PPC64 if (TRAP(regs) != 0x900 && TRAP(regs) != 0xf00 && TRAP(regs) != 0x260) this_cpu_set_ftrace_enabled(state->ftrace_enabled); diff --git a/arch/powerpc/include/asm/processor.h b/arch/powerpc/include/asm/processor.h index 8acc3590c971..eedc3c775141 100644 --- a/arch/powerpc/include/asm/processor.h +++ b/arch/powerpc/include/asm/processor.h @@ -393,6 +393,7 @@ extern unsigned long isa300_idle_stop_mayloss(unsigned long psscr_val); extern unsigned long isa206_idle_insn_mayloss(unsigned long type); #ifdef CONFIG_PPC_970_NAP extern void power4_idle_nap(void); +void power4_idle_nap_return(void); #endif extern unsigned long cpuidle_disable; diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h index 386d576673a1..bf137151100b 100644 --- a/arch/powerpc/include/asm/thread_info.h +++ b/arch/powerpc/include/asm/thread_info.h @@ -152,6 +152,12 @@ void arch_setup_new_exec(void); #ifndef __ASSEMBLY__ +static inline void clear_thread_local_flags(unsigned int flags) +{ + struct thread_info *ti = current_thread_info(); + ti->local_flags &= ~flags; +} + static inline bool test_thread_local_flags(unsigned int flags) { struct thread_info *ti = current_thread_info(); diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index 27351276c54b..5478ffa85603 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -692,25 +692,6 @@ END_FTR_SECTION_IFSET(CPU_FTR_CFAR) ld r1,GPR1(r1) .endm -/* - * When the idle code in power4_idle puts the CPU into NAP mode, - * it has to do so in a loop, and relies on the external interrupt - * and decrementer interrupt entry code to get it out of the loop. - * It sets the _TLF_NAPPING bit in current_thread_info()->local_flags - * to signal that it is in the loop and needs help to get out. - */ -#ifdef CONFIG_PPC_970_NAP -#define FINISH_NAP \ -BEGIN_FTR_SECTION \ - ld r11, PACA_THREAD_INFO(r13); \ - ld r9,TI_LOCAL_FLAGS(r11); \ - andi. r10,r9,_TLF_NAPPING; \ - bnel power4_fixup_nap; \ -END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP) -#else -#define FINISH_NAP -#endif - /* * There are a few constraints to be concerned with. * - Real mode exceptions code/data must be located at their physical location. @@ -1248,7 +1229,6 @@ EXC_COMMON_BEGIN(machine_check_common) */ GEN_COMMON machine_check - FINISH_NAP /* Enable MSR_RI when finished with PACA_EXMC */ li r10,MSR_RI mtmsrd r10,1 @@ -1576,7 +1556,6 @@ EXC_VIRT_BEGIN(hardware_interrupt, 0x4500, 0x100) EXC_VIRT_END(hardware_interrupt, 0x4500, 0x100) EXC_COMMON_BEGIN(hardware_interrupt_common) GEN_COMMON hardware_interrupt - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD bl do_IRQ b interrupt_return @@ -1761,7 +1740,6 @@ EXC_VIRT_BEGIN(decrementer, 0x4900, 0x80) EXC_VIRT_END(decrementer, 0x4900, 0x80) EXC_COMMON_BEGIN(decrementer_common) GEN_COMMON decrementer - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD bl timer_interrupt b interrupt_return @@ -1846,7 +1824,6 @@ EXC_VIRT_BEGIN(doorbell_super, 0x4a00, 0x100) EXC_VIRT_END(doorbell_super, 0x4a00, 0x100) EXC_COMMON_BEGIN(doorbell_super_common) GEN_COMMON doorbell_super - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD #ifdef CONFIG_PPC_DOORBELL bl doorbell_exception @@ -2200,7 +2177,6 @@ EXC_COMMON_BEGIN(hmi_exception_early_common) EXC_COMMON_BEGIN(hmi_exception_common) GEN_COMMON hmi_exception - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD bl handle_hmi_exception b interrupt_return @@ -2229,7 +2205,6 @@ EXC_VIRT_BEGIN(h_doorbell, 0x4e80, 0x20) EXC_VIRT_END(h_doorbell, 0x4e80, 0x20) EXC_COMMON_BEGIN(h_doorbell_common) GEN_COMMON h_doorbell - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD #ifdef CONFIG_PPC_DOORBELL bl doorbell_exception @@ -2262,7 +2237,6 @@ EXC_VIRT_BEGIN(h_virt_irq, 0x4ea0, 0x20) EXC_VIRT_END(h_virt_irq, 0x4ea0, 0x20) EXC_COMMON_BEGIN(h_virt_irq_common) GEN_COMMON h_virt_irq - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD bl do_IRQ b interrupt_return @@ -2308,7 +2282,6 @@ EXC_VIRT_BEGIN(performance_monitor, 0x4f00, 0x20) EXC_VIRT_END(performance_monitor, 0x4f00, 0x20) EXC_COMMON_BEGIN(performance_monitor_common) GEN_COMMON performance_monitor - FINISH_NAP addi r3,r1,STACK_FRAME_OVERHEAD bl performance_monitor_exception b interrupt_return @@ -3059,24 +3032,6 @@ USE_FIXED_SECTION(virt_trampolines) __end_interrupts: DEFINE_FIXED_SYMBOL(__end_interrupts) -#ifdef CONFIG_PPC_970_NAP - /* - * Called by exception entry code if _TLF_NAPPING was set, this clears - * the NAPPING flag, and redirects the exception exit to - * power4_fixup_nap_return. - */ - .globl power4_fixup_nap -EXC_COMMON_BEGIN(power4_fixup_nap) - andc r9,r9,r10 - std r9,TI_LOCAL_FLAGS(r11) - LOAD_REG_ADDR(r10, power4_idle_nap_return) - std r10,_NIP(r1) - blr - -power4_idle_nap_return: - blr -#endif - CLOSE_FIXED_SECTION(real_vectors); CLOSE_FIXED_SECTION(real_trampolines); CLOSE_FIXED_SECTION(virt_vectors); diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 22f249b6f58d..27d2e6a72ec9 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -201,4 +201,8 @@ _GLOBAL(power4_idle_nap) mtmsrd r7 isync b 1b + + .globl power4_idle_nap_return +power4_idle_nap_return: + blr #endif
There is no need for this to be in asm, use the new intrrupt entry wrapper. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> --- arch/powerpc/include/asm/interrupt.h | 15 +++++++++ arch/powerpc/include/asm/processor.h | 1 + arch/powerpc/include/asm/thread_info.h | 6 ++++ arch/powerpc/kernel/exceptions-64s.S | 45 -------------------------- arch/powerpc/kernel/idle_book3s.S | 4 +++ 5 files changed, 26 insertions(+), 45 deletions(-)