From d6d048192b1d22cb8f09da0cc936095ec2cb969c Mon Sep 17 00:00:00 2001 From: Daniel Hellstrom Date: Mon, 2 May 2011 00:08:51 +0000 Subject: [PATCH] sparc32: implement SMP IPIs using the generic functions The current sparc32 SMP IPI generation is implemented the cross call function. The cross call function uses IRQ15 the NMI, this is has the effect that IPIs will interrupt IRQ critical areas and hang the system. Typically on/after spin_lock_irqsave calls can be aborted. The cross call functionality must still exist to flush cache/TLBS. This patch provides CPU models a custom way to implement generation of IPIs on the generic code's request. The typical approach is to generate an IRQ for each IPI case. After this patch each sparc32 SMP CPU model needs to implement IPIs in order to function properly. Signed-off-by: Daniel Hellstrom Signed-off-by: David S. Miller --- arch/sparc/Kconfig | 3 +- arch/sparc/include/asm/cpudata_32.h | 5 +++ arch/sparc/include/asm/smp_32.h | 22 ++++++-------- arch/sparc/kernel/irq_32.c | 10 ++++++ arch/sparc/kernel/smp_32.c | 47 ++++++++++++++++++++++++++++- 5 files changed, 71 insertions(+), 16 deletions(-) diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig index a56630d4f14b..63a027c9ada5 100644 --- a/arch/sparc/Kconfig +++ b/arch/sparc/Kconfig @@ -28,7 +28,7 @@ config SPARC select HAVE_GENERIC_HARDIRQS select GENERIC_HARDIRQS_NO_DEPRECATED select GENERIC_IRQ_SHOW - + select USE_GENERIC_SMP_HELPERS if SMP config SPARC32 def_bool !64BIT @@ -47,7 +47,6 @@ config SPARC64 select HAVE_DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD select HAVE_SYSCALL_TRACEPOINTS - select USE_GENERIC_SMP_HELPERS if SMP select RTC_DRV_CMOS select RTC_DRV_BQ4802 select RTC_DRV_SUN4V diff --git a/arch/sparc/include/asm/cpudata_32.h b/arch/sparc/include/asm/cpudata_32.h index 31d48a0e32c7..a4c5a938b936 100644 --- a/arch/sparc/include/asm/cpudata_32.h +++ b/arch/sparc/include/asm/cpudata_32.h @@ -16,6 +16,10 @@ typedef struct { unsigned long clock_tick; unsigned int multiplier; unsigned int counter; +#ifdef CONFIG_SMP + unsigned int irq_resched_count; + unsigned int irq_call_count; +#endif int prom_node; int mid; int next; @@ -23,5 +27,6 @@ typedef struct { DECLARE_PER_CPU(cpuinfo_sparc, __cpu_data); #define cpu_data(__cpu) per_cpu(__cpu_data, (__cpu)) +#define local_cpu_data() __get_cpu_var(__cpu_data) #endif /* _SPARC_CPUDATA_H */ diff --git a/arch/sparc/include/asm/smp_32.h b/arch/sparc/include/asm/smp_32.h index d7837dcb2525..7a8e6cbd640c 100644 --- a/arch/sparc/include/asm/smp_32.h +++ b/arch/sparc/include/asm/smp_32.h @@ -50,12 +50,19 @@ void smp_callin(void); void smp_boot_cpus(void); void smp_store_cpu_info(int); +void smp_resched_interrupt(void); +void smp_call_function_single_interrupt(void); +void smp_call_function_interrupt(void); + struct seq_file; void smp_bogo(struct seq_file *); void smp_info(struct seq_file *); BTFIXUPDEF_CALL(void, smp_cross_call, smpfunc_t, cpumask_t, unsigned long, unsigned long, unsigned long, unsigned long) BTFIXUPDEF_CALL(int, __hard_smp_processor_id, void) +BTFIXUPDEF_CALL(void, smp_ipi_resched, int); +BTFIXUPDEF_CALL(void, smp_ipi_single, int); +BTFIXUPDEF_CALL(void, smp_ipi_mask_one, int); BTFIXUPDEF_BLACKBOX(hard_smp_processor_id) BTFIXUPDEF_BLACKBOX(load_current) @@ -73,19 +80,8 @@ static inline void xc4(smpfunc_t func, unsigned long arg1, unsigned long arg2, unsigned long arg3, unsigned long arg4) { smp_cross_call(func, cpu_online_map, arg1, arg2, arg3, arg4); } -static inline int smp_call_function(void (*func)(void *info), void *info, int wait) -{ - xc1((smpfunc_t)func, (unsigned long)info); - return 0; -} - -static inline int smp_call_function_single(int cpuid, void (*func) (void *info), - void *info, int wait) -{ - smp_cross_call((smpfunc_t)func, cpumask_of_cpu(cpuid), - (unsigned long) info, 0, 0, 0); - return 0; -} +extern void arch_send_call_function_single_ipi(int cpu); +extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); static inline int cpu_logical_map(int cpu) { diff --git a/arch/sparc/kernel/irq_32.c b/arch/sparc/kernel/irq_32.c index 197e1ba85484..9b89d842913c 100644 --- a/arch/sparc/kernel/irq_32.c +++ b/arch/sparc/kernel/irq_32.c @@ -206,6 +206,16 @@ int arch_show_interrupts(struct seq_file *p, int prec) { int j; +#ifdef CONFIG_SMP + seq_printf(p, "RES: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_data(j).irq_resched_count); + seq_printf(p, " IPI rescheduling interrupts\n"); + seq_printf(p, "CAL: "); + for_each_online_cpu(j) + seq_printf(p, "%10u ", cpu_data(j).irq_call_count); + seq_printf(p, " IPI function call interrupts\n"); +#endif seq_printf(p, "NMI: "); for_each_online_cpu(j) seq_printf(p, "%10u ", cpu_data(j).counter); diff --git a/arch/sparc/kernel/smp_32.c b/arch/sparc/kernel/smp_32.c index 4a1d5b7f20d3..2710602281de 100644 --- a/arch/sparc/kernel/smp_32.c +++ b/arch/sparc/kernel/smp_32.c @@ -123,13 +123,58 @@ struct linux_prom_registers smp_penguin_ctable __cpuinitdata = { 0 }; void smp_send_reschedule(int cpu) { - /* See sparc64 */ + /* + * CPU model dependent way of implementing IPI generation targeting + * a single CPU. The trap handler needs only to do trap entry/return + * to call schedule. + */ + BTFIXUP_CALL(smp_ipi_resched)(cpu); } void smp_send_stop(void) { } +void arch_send_call_function_single_ipi(int cpu) +{ + /* trigger one IPI single call on one CPU */ + BTFIXUP_CALL(smp_ipi_single)(cpu); +} + +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + int cpu; + + /* trigger IPI mask call on each CPU */ + for_each_cpu(cpu, mask) + BTFIXUP_CALL(smp_ipi_mask_one)(cpu); +} + +void smp_resched_interrupt(void) +{ + local_cpu_data().irq_resched_count++; + /* + * do nothing, since it all was about calling re-schedule + * routine called by interrupt return code. + */ +} + +void smp_call_function_single_interrupt(void) +{ + irq_enter(); + generic_smp_call_function_single_interrupt(); + local_cpu_data().irq_call_count++; + irq_exit(); +} + +void smp_call_function_interrupt(void) +{ + irq_enter(); + generic_smp_call_function_interrupt(); + local_cpu_data().irq_call_count++; + irq_exit(); +} + void smp_flush_cache_all(void) { xc0((smpfunc_t) BTFIXUP_CALL(local_flush_cache_all)); -- GitLab