diff options
| -rw-r--r-- | arch/arm/kernel/smp.c | 70 | ||||
| -rw-r--r-- | arch/arm64/kernel/smp.c | 65 | ||||
| -rw-r--r-- | include/linux/ftrace_event.h | 34 | ||||
| -rw-r--r-- | include/linux/tracepoint.h | 44 | ||||
| -rw-r--r-- | include/trace/events/ipi.h | 89 |
5 files changed, 214 insertions, 88 deletions
diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 7c4fada440f..9388a3d479e 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -47,6 +47,9 @@ #include <asm/mach/arch.h> #include <asm/mpu.h> +#define CREATE_TRACE_POINTS +#include <trace/events/ipi.h> + /* * as from 2.5, kernels no longer have an init_tasks structure * so we need some other way of telling a new secondary core @@ -430,38 +433,15 @@ void __init smp_prepare_cpus(unsigned int max_cpus) } } -static void (*smp_cross_call)(const struct cpumask *, unsigned int); +static void (*__smp_cross_call)(const struct cpumask *, unsigned int); void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int)) { - if (!smp_cross_call) - smp_cross_call = fn; -} - -void arch_send_call_function_ipi_mask(const struct cpumask *mask) -{ - smp_cross_call(mask, IPI_CALL_FUNC); -} - -void arch_send_wakeup_ipi_mask(const struct cpumask *mask) -{ - smp_cross_call(mask, IPI_WAKEUP); -} - -void arch_send_call_function_single_ipi(int cpu) -{ - smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); + if (!__smp_cross_call) + __smp_cross_call = fn; } -#ifdef CONFIG_IRQ_WORK -void arch_irq_work_raise(void) -{ - if (is_smp()) - smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK); -} -#endif - -static const char *ipi_types[NR_IPI] = { +static const char *ipi_types[NR_IPI] __tracepoint_string = { #define S(x,s) [x] = s S(IPI_WAKEUP, "CPU wakeup interrupts"), S(IPI_TIMER, "Timer broadcast interrupts"), @@ -473,6 +453,12 @@ static const char *ipi_types[NR_IPI] = { S(IPI_COMPLETION, "completion interrupts"), }; +static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) +{ + trace_ipi_raise(target, ipi_types[ipinr]); + __smp_cross_call(target, ipinr); +} + void show_ipi_list(struct seq_file *p, int prec) { unsigned int cpu, i; @@ -499,6 +485,29 @@ u64 smp_irq_stat_cpu(unsigned int cpu) return sum; } +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_CALL_FUNC); +} + +void arch_send_wakeup_ipi_mask(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_WAKEUP); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); +} + +#ifdef CONFIG_IRQ_WORK +void arch_irq_work_raise(void) +{ + if (is_smp()) + smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK); +} +#endif + #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST void tick_broadcast(const struct cpumask *mask) { @@ -556,8 +565,10 @@ void handle_IPI(int ipinr, struct pt_regs *regs) unsigned int cpu = smp_processor_id(); struct pt_regs *old_regs = set_irq_regs(regs); - if (ipinr < NR_IPI) + if ((unsigned)ipinr < NR_IPI) { + trace_ipi_entry(ipi_types[ipinr]); __inc_irq_stat(cpu, ipi_irqs[ipinr]); + } switch (ipinr) { case IPI_WAKEUP: @@ -612,6 +623,9 @@ void handle_IPI(int ipinr, struct pt_regs *regs) cpu, ipinr); break; } + + if ((unsigned)ipinr < NR_IPI) + trace_ipi_exit(ipi_types[ipinr]); set_irq_regs(old_regs); } diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 3e2f5ebbf63..47433971810 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -51,6 +51,9 @@ #include <asm/tlbflush.h> #include <asm/ptrace.h> +#define CREATE_TRACE_POINTS +#include <trace/events/ipi.h> + /* * as from 2.5, kernels no longer have an init_tasks structure * so we need some other way of telling a new secondary core @@ -313,8 +316,6 @@ void __init smp_prepare_boot_cpu(void) set_my_cpu_offset(per_cpu_offset(smp_processor_id())); } -static void (*smp_cross_call)(const struct cpumask *, unsigned int); - /* * Enumerate the possible CPU set from the device tree and build the * cpu logical map array containing MPIDR values related to logical @@ -469,32 +470,15 @@ void __init smp_prepare_cpus(unsigned int max_cpus) } } +static void (*__smp_cross_call)(const struct cpumask *, unsigned int); void __init set_smp_cross_call(void (*fn)(const struct cpumask *, unsigned int)) { - smp_cross_call = fn; + __smp_cross_call = fn; } -void arch_send_call_function_ipi_mask(const struct cpumask *mask) -{ - smp_cross_call(mask, IPI_CALL_FUNC); -} - -void arch_send_call_function_single_ipi(int cpu) -{ - smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); -} - -#ifdef CONFIG_IRQ_WORK -void arch_irq_work_raise(void) -{ - if (smp_cross_call) - smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK); -} -#endif - -static const char *ipi_types[NR_IPI] = { -#define S(x,s) [x - IPI_RESCHEDULE] = s +static const char *ipi_types[NR_IPI] __tracepoint_string = { +#define S(x,s) [x] = s S(IPI_RESCHEDULE, "Rescheduling interrupts"), S(IPI_CALL_FUNC, "Function call interrupts"), S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"), @@ -503,12 +487,18 @@ static const char *ipi_types[NR_IPI] = { S(IPI_IRQ_WORK, "IRQ work interrupts"), }; +static void smp_cross_call(const struct cpumask *target, unsigned int ipinr) +{ + trace_ipi_raise(target, ipi_types[ipinr]); + __smp_cross_call(target, ipinr); +} + void show_ipi_list(struct seq_file *p, int prec) { unsigned int cpu, i; for (i = 0; i < NR_IPI; i++) { - seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i + IPI_RESCHEDULE, + seq_printf(p, "%*s%u:%s", prec - 1, "IPI", i, prec >= 4 ? " " : ""); for_each_online_cpu(cpu) seq_printf(p, "%10u ", @@ -528,6 +518,24 @@ u64 smp_irq_stat_cpu(unsigned int cpu) return sum; } +void arch_send_call_function_ipi_mask(const struct cpumask *mask) +{ + smp_cross_call(mask, IPI_CALL_FUNC); +} + +void arch_send_call_function_single_ipi(int cpu) +{ + smp_cross_call(cpumask_of(cpu), IPI_CALL_FUNC_SINGLE); +} + +#ifdef CONFIG_IRQ_WORK +void arch_irq_work_raise(void) +{ + if (__smp_cross_call) + smp_cross_call(cpumask_of(smp_processor_id()), IPI_IRQ_WORK); +} +#endif + static DEFINE_RAW_SPINLOCK(stop_lock); /* @@ -559,8 +567,10 @@ void handle_IPI(int ipinr, struct pt_regs *regs) unsigned int cpu = smp_processor_id(); struct pt_regs *old_regs = set_irq_regs(regs); - if (ipinr >= IPI_RESCHEDULE && ipinr < IPI_RESCHEDULE + NR_IPI) - __inc_irq_stat(cpu, ipi_irqs[ipinr - IPI_RESCHEDULE]); + if ((unsigned)ipinr < NR_IPI) { + trace_ipi_entry(ipi_types[ipinr]); + __inc_irq_stat(cpu, ipi_irqs[ipinr]); + } switch (ipinr) { case IPI_RESCHEDULE: @@ -605,6 +615,9 @@ void handle_IPI(int ipinr, struct pt_regs *regs) pr_crit("CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); break; } + + if ((unsigned)ipinr < NR_IPI) + trace_ipi_exit(ipi_types[ipinr]); set_irq_regs(old_regs); } diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 06c6faa9e5c..28672e87e91 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -571,40 +571,6 @@ do { \ __trace_printk(ip, fmt, ##args); \ } while (0) -/** - * tracepoint_string - register constant persistent string to trace system - * @str - a constant persistent string that will be referenced in tracepoints - * - * If constant strings are being used in tracepoints, it is faster and - * more efficient to just save the pointer to the string and reference - * that with a printf "%s" instead of saving the string in the ring buffer - * and wasting space and time. - * - * The problem with the above approach is that userspace tools that read - * the binary output of the trace buffers do not have access to the string. - * Instead they just show the address of the string which is not very - * useful to users. - * - * With tracepoint_string(), the string will be registered to the tracing - * system and exported to userspace via the debugfs/tracing/printk_formats - * file that maps the string address to the string text. This way userspace - * tools that read the binary buffers have a way to map the pointers to - * the ASCII strings they represent. - * - * The @str used must be a constant string and persistent as it would not - * make sense to show a string that no longer exists. But it is still fine - * to be used with modules, because when modules are unloaded, if they - * had tracepoints, the ring buffers are cleared too. As long as the string - * does not change during the life of the module, it is fine to use - * tracepoint_string() within a module. - */ -#define tracepoint_string(str) \ - ({ \ - static const char *___tp_str __tracepoint_string = str; \ - ___tp_str; \ - }) -#define __tracepoint_string __attribute__((section("__tracepoint_str"))) - #ifdef CONFIG_PERF_EVENTS struct perf_event; diff --git a/include/linux/tracepoint.h b/include/linux/tracepoint.h index 2e2a5f7717e..b1293f15f59 100644 --- a/include/linux/tracepoint.h +++ b/include/linux/tracepoint.h @@ -249,6 +249,50 @@ extern void syscall_unregfunc(void); #endif /* CONFIG_TRACEPOINTS */ +#ifdef CONFIG_TRACING +/** + * tracepoint_string - register constant persistent string to trace system + * @str - a constant persistent string that will be referenced in tracepoints + * + * If constant strings are being used in tracepoints, it is faster and + * more efficient to just save the pointer to the string and reference + * that with a printf "%s" instead of saving the string in the ring buffer + * and wasting space and time. + * + * The problem with the above approach is that userspace tools that read + * the binary output of the trace buffers do not have access to the string. + * Instead they just show the address of the string which is not very + * useful to users. + * + * With tracepoint_string(), the string will be registered to the tracing + * system and exported to userspace via the debugfs/tracing/printk_formats + * file that maps the string address to the string text. This way userspace + * tools that read the binary buffers have a way to map the pointers to + * the ASCII strings they represent. + * + * The @str used must be a constant string and persistent as it would not + * make sense to show a string that no longer exists. But it is still fine + * to be used with modules, because when modules are unloaded, if they + * had tracepoints, the ring buffers are cleared too. As long as the string + * does not change during the life of the module, it is fine to use + * tracepoint_string() within a module. + */ +#define tracepoint_string(str) \ + ({ \ + static const char *___tp_str __tracepoint_string = str; \ + ___tp_str; \ + }) +#define __tracepoint_string __attribute__((section("__tracepoint_str"))) +#else +/* + * tracepoint_string() is used to save the string address for userspace + * tracing tools. When tracing isn't configured, there's no need to save + * anything. + */ +# define tracepoint_string(str) str +# define __tracepoint_string +#endif + /* * The need for the DECLARE_TRACE_NOARGS() is to handle the prototype * (void). "void" is a special value in a function prototype and can diff --git a/include/trace/events/ipi.h b/include/trace/events/ipi.h new file mode 100644 index 00000000000..834a7362a61 --- /dev/null +++ b/include/trace/events/ipi.h @@ -0,0 +1,89 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM ipi + +#if !defined(_TRACE_IPI_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_IPI_H + +#include <linux/tracepoint.h> + +/** + * ipi_raise - called when a smp cross call is made + * + * @mask: mask of recipient CPUs for the IPI + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string. + */ +TRACE_EVENT(ipi_raise, + + TP_PROTO(const struct cpumask *mask, const char *reason), + + TP_ARGS(mask, reason), + + TP_STRUCT__entry( + __bitmask(target_cpus, nr_cpumask_bits) + __field(const char *, reason) + ), + + TP_fast_assign( + __assign_bitmask(target_cpus, cpumask_bits(mask), nr_cpumask_bits); + __entry->reason = reason; + ), + + TP_printk("target_mask=%s (%s)", __get_bitmask(target_cpus), __entry->reason) +); + +DECLARE_EVENT_CLASS(ipi_handler, + + TP_PROTO(const char *reason), + + TP_ARGS(reason), + + TP_STRUCT__entry( + __field(const char *, reason) + ), + + TP_fast_assign( + __entry->reason = reason; + ), + + TP_printk("(%s)", __entry->reason) +); + +/** + * ipi_entry - called immediately before the IPI handler + * + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string, ideally the same as used with trace_ipi_raise + * for that IPI. + */ +DEFINE_EVENT(ipi_handler, ipi_entry, + + TP_PROTO(const char *reason), + + TP_ARGS(reason) +); + +/** + * ipi_exit - called immediately after the IPI handler returns + * + * @reason: string identifying the IPI purpose + * + * It is necessary for @reason to be a static string declared with + * __tracepoint_string, ideally the same as used with trace_ipi_raise for + * that IPI. + */ +DEFINE_EVENT(ipi_handler, ipi_exit, + + TP_PROTO(const char *reason), + + TP_ARGS(reason) +); + +#endif /* _TRACE_IPI_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h> |