diff options
| -rw-r--r-- | include/linux/ftrace.h | 19 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_boot.c | 101 |
3 files changed, 124 insertions, 0 deletions
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 5de9903645d..91954eb6460 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -5,6 +5,8 @@ #include <linux/linkage.h> #include <linux/fs.h> +#include <linux/init.h> +#include <linux/types.h> extern int ftrace_enabled; extern int @@ -209,4 +211,21 @@ ftrace_init_module(unsigned long *start, unsigned long *end) { } #endif +struct boot_trace { + pid_t caller; + initcall_t func; + int result; + unsigned long long duration; +}; + +#ifdef CONFIG_BOOT_TRACER +extern void trace_boot(struct boot_trace *it); +extern void start_boot_trace(void); +#else +static inline void trace_boot(struct boot_trace *it) { } +static inline void start_boot_trace(void) { } +#endif + + + #endif /* _LINUX_FTRACE_H */ diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index cb2c3fb7dd5..b28bf8812ef 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -6,6 +6,7 @@ #include <linux/sched.h> #include <linux/clocksource.h> #include <linux/mmiotrace.h> +#include <linux/ftrace.h> enum trace_type { __TRACE_FIRST_TYPE = 0, @@ -19,6 +20,7 @@ enum trace_type { TRACE_SPECIAL, TRACE_MMIO_RW, TRACE_MMIO_MAP, + TRACE_BOOT, __TRACE_LAST_TYPE }; @@ -30,6 +32,7 @@ struct ftrace_entry { unsigned long ip; unsigned long parent_ip; }; +extern struct tracer boot_tracer; /* * Context switch trace entry - which task (and prio) we switched from/to: @@ -108,6 +111,7 @@ struct trace_field { struct print_entry print; struct mmiotrace_rw mmiorw; struct mmiotrace_map mmiomap; + struct boot_trace initcall; }; }; diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c new file mode 100644 index 00000000000..c65ef8ffd6b --- /dev/null +++ b/kernel/trace/trace_boot.c @@ -0,0 +1,101 @@ +/* + * ring buffer based initcalls tracer + * + * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com> + * + */ + +#include <linux/init.h> +#include <linux/debugfs.h> +#include <linux/ftrace.h> + +#include "trace.h" + +static struct trace_array *boot_trace; +static int trace_boot_enabled; + + +/* Should be started after do_pre_smp_initcalls() in init/main.c */ +void start_boot_trace(void) +{ + trace_boot_enabled = 1; +} + +void stop_boot_trace(struct trace_array *tr) +{ + trace_boot_enabled = 0; +} + +static void boot_trace_init(struct trace_array *tr) +{ + int cpu; + boot_trace = tr; + + trace_boot_enabled = 0; + + for_each_cpu_mask(cpu, cpu_possible_map) + tracing_reset(tr->data[cpu]); +} + +static void boot_trace_ctrl_update(struct trace_array *tr) +{ + if (tr->ctrl) + start_boot_trace(); + else + stop_boot_trace(tr); +} + +static int initcall_print_line(struct trace_iterator *iter) +{ + int ret = 1; + struct trace_entry *entry = iter->ent; + struct boot_trace *it = &entry->field.initcall; + struct trace_seq *s = &iter->seq; + + if (iter->ent->type == TRACE_BOOT) + ret = trace_seq_printf(s, "%pF called from %i " + "returned %d after %lld msecs\n", + it->func, it->caller, it->result, + it->duration); + if (ret) + return 1; + return 0; +} + +struct tracer boot_tracer __read_mostly = +{ + .name = "initcall", + .init = boot_trace_init, + .reset = stop_boot_trace, + .ctrl_update = boot_trace_ctrl_update, + .print_line = initcall_print_line, +}; + + +void trace_boot(struct boot_trace *it) +{ + struct trace_entry *entry; + struct trace_array_cpu *data; + unsigned long irq_flags; + struct trace_array *tr = boot_trace; + + if (!trace_boot_enabled) + return; + + preempt_disable(); + data = tr->data[smp_processor_id()]; + + raw_local_irq_save(irq_flags); + __raw_spin_lock(&data->lock); + + entry = tracing_get_trace_entry(tr, data); + tracing_generic_entry_update(entry, 0); + entry->type = TRACE_BOOT; + entry->field.initcall = *it; + + __raw_spin_unlock(&data->lock); + raw_local_irq_restore(irq_flags); + trace_wake_up(); + + preempt_enable(); +} |