From b77e38aa240c3bd9c55c98b9f7c81541e042eae5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Tue, 24 Feb 2009 10:21:36 -0500 Subject: tracing: add event trace infrastructure This patch creates the event tracing infrastructure of ftrace. It will create the files: /debug/tracing/available_events /debug/tracing/set_event The available_events will list the trace points that have been registered with the event tracer. set_events will allow the user to enable or disable an event hook. example: # echo sched_wakeup > /debug/tracing/set_event Will enable the sched_wakeup event (if it is registered). # echo "!sched_wakeup" >> /debug/tracing/set_event Will disable the sched_wakeup event (and only that event). # echo > /debug/tracing/set_event Will disable all events (notice the '>') # cat /debug/tracing/available_events > /debug/tracing/set_event Will enable all registered event hooks. Signed-off-by: Steven Rostedt --- include/asm-generic/vmlinux.lds.h | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index c61fab1dd2f8..0add6b28c366 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -61,6 +61,14 @@ #define BRANCH_PROFILE() #endif +#ifdef CONFIG_EVENT_TRACER +#define FTRACE_EVENTS() VMLINUX_SYMBOL(__start_ftrace_events) = .; \ + *(_ftrace_events) \ + VMLINUX_SYMBOL(__stop_ftrace_events) = .; +#else +#define FTRACE_EVENTS() +#endif + /* .data section */ #define DATA_DATA \ *(.data) \ @@ -81,7 +89,8 @@ *(__tracepoints) \ VMLINUX_SYMBOL(__stop___tracepoints) = .; \ LIKELY_PROFILE() \ - BRANCH_PROFILE() + BRANCH_PROFILE() \ + FTRACE_EVENTS() #define RO_DATA(align) \ . = ALIGN((align)); \ -- cgit v1.2.3 From 1ba28e02a18cbdbea123836f6c98efb09cbf59ec Mon Sep 17 00:00:00 2001 From: Lai Jiangshan Date: Fri, 6 Mar 2009 17:21:48 +0100 Subject: tracing: add trace_bprintk() Impact: add a generic printk() for tracing, like trace_printk() trace_bprintk() uses the infrastructure to record events on ring_buffer. [ fweisbec@gmail.com: ported to latest -tip, made it work if !CONFIG_MODULES, never free the format strings from modules because we can't keep track of them and conditionnaly create the ftrace format strings section (reported by Steven Rostedt) ] Signed-off-by: Lai Jiangshan Signed-off-by: Frederic Weisbecker Acked-by: Steven Rostedt LKML-Reference: <1236356510-8381-4-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- include/asm-generic/vmlinux.lds.h | 9 ++++ include/linux/ftrace.h | 21 ++++++++++ include/linux/module.h | 5 +++ kernel/module.c | 6 +++ kernel/trace/trace.c | 15 +++++++ kernel/trace/trace_bprintk.c | 87 ++++++++++++++++++++++++++++++++++----- 6 files changed, 133 insertions(+), 10 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 0add6b28c366..48ade3168b13 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -69,6 +69,14 @@ #define FTRACE_EVENTS() #endif +#ifdef CONFIG_TRACING +#define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .; \ + *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \ + VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .; +#else +#define TRACE_PRINTKS() +#endif + /* .data section */ #define DATA_DATA \ *(.data) \ @@ -100,6 +108,7 @@ *(__vermagic) /* Kernel version magic */ \ *(__markers_strings) /* Markers: strings */ \ *(__tracepoints_strings)/* Tracepoints: strings */ \ + TRACE_PRINTKS() \ } \ \ .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \ diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 1c9cdca02580..1cc8ca453a9b 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -225,6 +225,27 @@ extern int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr); #ifdef CONFIG_TRACE_BPRINTK extern int trace_vbprintk(unsigned long ip, const char *fmt, va_list args); +extern int __trace_bprintk(unsigned long ip, const char *fmt, ...) + __attribute__ ((format (printf, 2, 3))); + +static inline void ____trace_bprintk_check_format(const char *fmt, ...) + __attribute__ ((format (printf, 1, 2))); +static inline void ____trace_bprintk_check_format(const char *fmt, ...) {} +#define __trace_bprintk_check_format(fmt, args...) \ +do { \ + if (0) \ + ____trace_bprintk_check_format(fmt, ##args); \ +} while (0) + +#define trace_bprintk(fmt, args...) \ +do { \ + static char *__attribute__((section("__trace_bprintk_fmt"))) \ + trace_bprintk_fmt = fmt; \ + __trace_bprintk_check_format(fmt, ##args); \ + __trace_bprintk(_THIS_IP_, trace_bprintk_fmt, ##args); \ +} while (0) +#else +#define trace_bprintk trace_printk #endif /* May be defined in arch */ diff --git a/include/linux/module.h b/include/linux/module.h index 145a75528cc1..8cbec972d8e7 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -329,6 +329,11 @@ struct module unsigned int num_tracepoints; #endif +#ifdef CONFIG_TRACE_BPRINTK + const char **trace_bprintk_fmt_start; + unsigned int num_trace_bprintk_fmt; +#endif + #ifdef CONFIG_MODULE_UNLOAD /* What modules depend on me? */ struct list_head modules_which_use_me; diff --git a/kernel/module.c b/kernel/module.c index 22d7379709da..2dece104f9a1 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -2158,6 +2158,12 @@ static noinline struct module *load_module(void __user *umod, &mod->num_tracepoints); #endif +#ifdef CONFIG_TRACE_BPRINTK + mod->trace_bprintk_fmt_start = section_objs(hdr, sechdrs, secstrings, + "__trace_bprintk_fmt", sizeof(char *), + &mod->num_trace_bprintk_fmt); +#endif + #ifdef CONFIG_MODVERSIONS if ((mod->num_syms && !mod->crcs) || (mod->num_gpl_syms && !mod->gpl_crcs) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index ff53509e19f8..46b3cd7a5752 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -3848,6 +3848,21 @@ out: } EXPORT_SYMBOL_GPL(trace_vbprintk); +int __trace_bprintk(unsigned long ip, const char *fmt, ...) +{ + int ret; + va_list ap; + + if (!fmt) + return 0; + + va_start(ap, fmt); + ret = trace_vbprintk(ip, fmt, ap); + va_end(ap); + return ret; +} +EXPORT_SYMBOL_GPL(__trace_bprintk); + static int trace_panic_handler(struct notifier_block *this, unsigned long event, void *unused) { diff --git a/kernel/trace/trace_bprintk.c b/kernel/trace/trace_bprintk.c index 1f8e532c3fb9..f4c245a5cd33 100644 --- a/kernel/trace/trace_bprintk.c +++ b/kernel/trace/trace_bprintk.c @@ -19,9 +19,21 @@ #include "trace.h" +#ifdef CONFIG_MODULES + /* binary printk basic */ static DEFINE_MUTEX(btrace_mutex); -static int btrace_metadata_count; +/* + * modules trace_bprintk()'s formats are autosaved in struct trace_bprintk_fmt + * which are queued on trace_bprintk_fmt_list. + */ +static LIST_HEAD(trace_bprintk_fmt_list); + +struct trace_bprintk_fmt { + struct list_head list; + char fmt[0]; +}; + static inline void lock_btrace(void) { @@ -33,26 +45,75 @@ static inline void unlock_btrace(void) mutex_unlock(&btrace_mutex); } -static void get_btrace_metadata(void) + +static inline struct trace_bprintk_fmt *lookup_format(const char *fmt) { - lock_btrace(); - btrace_metadata_count++; - unlock_btrace(); + struct trace_bprintk_fmt *pos; + list_for_each_entry(pos, &trace_bprintk_fmt_list, list) { + if (!strcmp(pos->fmt, fmt)) + return pos; + } + return NULL; } -static void put_btrace_metadata(void) +static +void hold_module_trace_bprintk_format(const char **start, const char **end) { + const char **iter; lock_btrace(); - btrace_metadata_count--; + for (iter = start; iter < end; iter++) { + struct trace_bprintk_fmt *tb_fmt = lookup_format(*iter); + if (tb_fmt) { + *iter = tb_fmt->fmt; + continue; + } + + tb_fmt = kmalloc(offsetof(struct trace_bprintk_fmt, fmt) + + strlen(*iter) + 1, GFP_KERNEL); + if (tb_fmt) { + list_add_tail(&tb_fmt->list, &trace_bprintk_fmt_list); + strcpy(tb_fmt->fmt, *iter); + *iter = tb_fmt->fmt; + } else + *iter = NULL; + } unlock_btrace(); } +static int module_trace_bprintk_format_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + struct module *mod = data; + if (mod->num_trace_bprintk_fmt) { + const char **start = mod->trace_bprintk_fmt_start; + const char **end = start + mod->num_trace_bprintk_fmt; + + if (val == MODULE_STATE_COMING) + hold_module_trace_bprintk_format(start, end); + } + return 0; +} + +#else /* !CONFIG_MODULES */ +__init static int +module_trace_bprintk_format_notify(struct notifier_block *self, + unsigned long val, void *data) +{ + return 0; +} +#endif /* CONFIG_MODULES */ + + +__initdata_or_module static +struct notifier_block module_trace_bprintk_format_nb = { + .notifier_call = module_trace_bprintk_format_notify, +}; + /* events tracer */ int trace_bprintk_enable; static void start_bprintk_trace(struct trace_array *tr) { - get_btrace_metadata(); tracing_reset_online_cpus(tr); trace_bprintk_enable = 1; } @@ -61,7 +122,6 @@ static void stop_bprintk_trace(struct trace_array *tr) { trace_bprintk_enable = 0; tracing_reset_online_cpus(tr); - put_btrace_metadata(); } static int init_bprintk_trace(struct trace_array *tr) @@ -81,7 +141,14 @@ static struct tracer bprintk_trace __read_mostly = static __init int init_bprintk(void) { - return register_tracer(&bprintk_trace); + int ret = register_module_notifier(&module_trace_bprintk_format_nb); + if (ret) + return ret; + + ret = register_tracer(&bprintk_trace); + if (ret) + unregister_module_notifier(&module_trace_bprintk_format_nb); + return ret; } device_initcall(init_bprintk); -- cgit v1.2.3 From 8a20d84d09ab5d121f989cd99e4fc5f4b49f98ba Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 9 Mar 2009 10:09:06 +0100 Subject: tracing: trace_printk() fix, move format array to data section Impact: fix kernel crash when using trace_printk() trace_printk_fmt section is defined into the readonly section. But we do: trace_printk_fmt = fmt; to fill in that table of format strings - which is not read-only. Under CONFIG_DEBUG_RODATA=y this crashes ... Cc: Frederic Weisbecker Cc: Steven Rostedt Cc: Peter Zijlstra LKML-Reference: <1236356510-8381-5-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- include/asm-generic/vmlinux.lds.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 48ade3168b13..d656b4624024 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -98,6 +98,7 @@ VMLINUX_SYMBOL(__stop___tracepoints) = .; \ LIKELY_PROFILE() \ BRANCH_PROFILE() \ + TRACE_PRINTKS() \ FTRACE_EVENTS() #define RO_DATA(align) \ @@ -108,7 +109,6 @@ *(__vermagic) /* Kernel version magic */ \ *(__markers_strings) /* Markers: strings */ \ *(__tracepoints_strings)/* Tracepoints: strings */ \ - TRACE_PRINTKS() \ } \ \ .rodata1 : AT(ADDR(.rodata1) - LOAD_OFFSET) { \ -- cgit v1.2.3 From bed1ffca022cc876fb83161d26670e9b5d3cf36b Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Fri, 13 Mar 2009 15:42:11 +0100 Subject: tracing/syscalls: core infrastructure for syscalls tracing, enhancements Impact: new feature This adds the generic support for syscalls tracing. This is currently exploited through a devoted tracer but other tracing engines can use it. (They just have to play with {start,stop}_ftrace_syscalls() and use the display callbacks unless they want to override them.) The syscalls prototypes definitions are abused here to steal some metadata informations: - syscall name, param types, param names, number of params The syscall addr is not directly saved during this definition because we don't know if its prototype is available in the namespace. But we don't really need it. The arch has just to build a function able to resolve the syscall number to its metadata struct. The current tracer prints the syscall names, parameters names and values (and their types optionally). Currently the value is a raw hex but higher level values diplaying is on my TODO list. Signed-off-by: Frederic Weisbecker LKML-Reference: <1236955332-10133-2-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- include/asm-generic/vmlinux.lds.h | 11 ++- include/linux/ftrace.h | 14 +++- include/linux/syscalls.h | 60 +++++++++++++++- kernel/trace/trace.h | 17 +++++ kernel/trace/trace_syscalls.c | 146 +++++++++++++++++++++++++++++++++++--- 5 files changed, 234 insertions(+), 14 deletions(-) (limited to 'include/asm-generic') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 0e0f39be6c8b..d3bc3c86df6a 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -77,6 +77,14 @@ #define TRACE_PRINTKS() #endif +#ifdef CONFIG_FTRACE_SYSCALLS +#define TRACE_SYSCALLS() VMLINUX_SYMBOL(__start_syscalls_metadata) = .; \ + *(__syscalls_metadata) \ + VMLINUX_SYMBOL(__stop_syscalls_metadata) = .; +#else +#define TRACE_SYSCALLS() +#endif + /* .data section */ #define DATA_DATA \ *(.data) \ @@ -99,7 +107,8 @@ LIKELY_PROFILE() \ BRANCH_PROFILE() \ TRACE_PRINTKS() \ - FTRACE_EVENTS() + FTRACE_EVENTS() \ + TRACE_SYSCALLS() #define RO_DATA(align) \ . = ALIGN((align)); \ diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index c146c1021a29..6dc1c652447e 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -506,13 +506,21 @@ static inline void trace_hw_branch_oops(void) {} /* * A syscall entry in the ftrace syscalls array. * - * @syscall_nr: syscall number + * @name: name of the syscall + * @nb_args: number of parameters it takes + * @types: list of types as strings + * @args: list of args as strings (args[i] matches types[i]) */ -struct syscall_trace_entry { - int syscall_nr; +struct syscall_metadata { + const char *name; + int nb_args; + const char **types; + const char **args; }; #ifdef CONFIG_FTRACE_SYSCALLS +extern void arch_init_ftrace_syscalls(void); +extern struct syscall_metadata *syscall_nr_to_meta(int nr); extern void start_ftrace_syscalls(void); extern void stop_ftrace_syscalls(void); extern void ftrace_syscall_enter(struct pt_regs *regs); diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index f9f900cfd066..0cff9bb80b02 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -65,6 +65,7 @@ struct old_linux_dirent; #include #include #include +#include #define __SC_DECL1(t1, a1) t1 a1 #define __SC_DECL2(t2, a2, ...) t2 a2, __SC_DECL1(__VA_ARGS__) @@ -95,7 +96,46 @@ struct old_linux_dirent; #define __SC_TEST5(t5, a5, ...) __SC_TEST(t5); __SC_TEST4(__VA_ARGS__) #define __SC_TEST6(t6, a6, ...) __SC_TEST(t6); __SC_TEST5(__VA_ARGS__) +#ifdef CONFIG_FTRACE_SYSCALLS +#define __SC_STR_ADECL1(t, a) #a +#define __SC_STR_ADECL2(t, a, ...) #a, __SC_STR_ADECL1(__VA_ARGS__) +#define __SC_STR_ADECL3(t, a, ...) #a, __SC_STR_ADECL2(__VA_ARGS__) +#define __SC_STR_ADECL4(t, a, ...) #a, __SC_STR_ADECL3(__VA_ARGS__) +#define __SC_STR_ADECL5(t, a, ...) #a, __SC_STR_ADECL4(__VA_ARGS__) +#define __SC_STR_ADECL6(t, a, ...) #a, __SC_STR_ADECL5(__VA_ARGS__) + +#define __SC_STR_TDECL1(t, a) #t +#define __SC_STR_TDECL2(t, a, ...) #t, __SC_STR_TDECL1(__VA_ARGS__) +#define __SC_STR_TDECL3(t, a, ...) #t, __SC_STR_TDECL2(__VA_ARGS__) +#define __SC_STR_TDECL4(t, a, ...) #t, __SC_STR_TDECL3(__VA_ARGS__) +#define __SC_STR_TDECL5(t, a, ...) #t, __SC_STR_TDECL4(__VA_ARGS__) +#define __SC_STR_TDECL6(t, a, ...) #t, __SC_STR_TDECL5(__VA_ARGS__) + +#define SYSCALL_METADATA(sname, nb) \ + static const struct syscall_metadata __used \ + __attribute__((__aligned__(4))) \ + __attribute__((section("__syscalls_metadata"))) \ + __syscall_meta_##sname = { \ + .name = "sys"#sname, \ + .nb_args = nb, \ + .types = types_##sname, \ + .args = args_##sname, \ + } + +#define SYSCALL_DEFINE0(sname) \ + static const struct syscall_metadata __used \ + __attribute__((__aligned__(4))) \ + __attribute__((section("__syscalls_metadata"))) \ + __syscall_meta_##sname = { \ + .name = "sys_"#sname, \ + .nb_args = 0, \ + }; \ + asmlinkage long sys_##sname(void) + +#else #define SYSCALL_DEFINE0(name) asmlinkage long sys_##name(void) +#endif + #define SYSCALL_DEFINE1(name, ...) SYSCALL_DEFINEx(1, _##name, __VA_ARGS__) #define SYSCALL_DEFINE2(name, ...) SYSCALL_DEFINEx(2, _##name, __VA_ARGS__) #define SYSCALL_DEFINE3(name, ...) SYSCALL_DEFINEx(3, _##name, __VA_ARGS__) @@ -117,10 +157,26 @@ struct old_linux_dirent; #endif #endif +#ifdef CONFIG_FTRACE_SYSCALLS +#define SYSCALL_DEFINEx(x, sname, ...) \ + static const char *types_##sname[] = { \ + __SC_STR_TDECL##x(__VA_ARGS__) \ + }; \ + static const char *args_##sname[] = { \ + __SC_STR_ADECL##x(__VA_ARGS__) \ + }; \ + SYSCALL_METADATA(sname, x); \ + __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) +#else +#define SYSCALL_DEFINEx(x, sname, ...) \ + __SYSCALL_DEFINEx(x, sname, __VA_ARGS__) +#endif + #ifdef CONFIG_HAVE_SYSCALL_WRAPPERS #define SYSCALL_DEFINE(name) static inline long SYSC_##name -#define SYSCALL_DEFINEx(x, name, ...) \ + +#define __SYSCALL_DEFINEx(x, name, ...) \ asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__)); \ static inline long SYSC##name(__SC_DECL##x(__VA_ARGS__)); \ asmlinkage long SyS##name(__SC_LONG##x(__VA_ARGS__)) \ @@ -134,7 +190,7 @@ struct old_linux_dirent; #else /* CONFIG_HAVE_SYSCALL_WRAPPERS */ #define SYSCALL_DEFINE(name) asmlinkage long sys_##name -#define SYSCALL_DEFINEx(x, name, ...) \ +#define __SYSCALL_DEFINEx(x, name, ...) \ asmlinkage long sys##name(__SC_DECL##x(__VA_ARGS__)) #endif /* CONFIG_HAVE_SYSCALL_WRAPPERS */ diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 3d49daae47dc..d80ca0d464d9 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -194,6 +194,19 @@ struct kmemtrace_free_entry { const void *ptr; }; +struct syscall_trace_enter { + struct trace_entry ent; + int nr; + unsigned long args[]; +}; + +struct syscall_trace_exit { + struct trace_entry ent; + int nr; + unsigned long ret; +}; + + /* * trace_flag_type is an enumeration that holds different * states when a trace occurs. These are: @@ -306,6 +319,10 @@ extern void __ftrace_bad_type(void); TRACE_KMEM_ALLOC); \ IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \ TRACE_KMEM_FREE); \ + IF_ASSIGN(var, ent, struct syscall_trace_enter, \ + TRACE_SYSCALL_ENTER); \ + IF_ASSIGN(var, ent, struct syscall_trace_exit, \ + TRACE_SYSCALL_EXIT); \ __ftrace_bad_type(); \ } while (0) diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 66cf97449af3..c72e599230ff 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -1,6 +1,5 @@ -#include #include - +#include #include #include "trace_output.h" @@ -8,6 +7,90 @@ static atomic_t refcount; +/* Our two options */ +enum { + TRACE_SYSCALLS_OPT_TYPES = 0x1, +}; + +static struct tracer_opt syscalls_opts[] = { + { TRACER_OPT(syscall_arg_type, TRACE_SYSCALLS_OPT_TYPES) }, + { } +}; + +static struct tracer_flags syscalls_flags = { + .val = 0, /* By default: no args types */ + .opts = syscalls_opts +}; + +enum print_line_t +print_syscall_enter(struct trace_iterator *iter, int flags) +{ + struct trace_seq *s = &iter->seq; + struct trace_entry *ent = iter->ent; + struct syscall_trace_enter *trace; + struct syscall_metadata *entry; + int i, ret, syscall; + + trace_assign_type(trace, ent); + + syscall = trace->nr; + + entry = syscall_nr_to_meta(syscall); + if (!entry) + goto end; + + ret = trace_seq_printf(s, "%s(", entry->name); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + for (i = 0; i < entry->nb_args; i++) { + /* parameter types */ + if (syscalls_flags.val & TRACE_SYSCALLS_OPT_TYPES) { + ret = trace_seq_printf(s, "%s ", entry->types[i]); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } + /* parameter values */ + ret = trace_seq_printf(s, "%s: %lx%s ", entry->args[i], + trace->args[i], + i == entry->nb_args - 1 ? ")" : ","); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + } + +end: + trace_seq_printf(s, "\n"); + return TRACE_TYPE_HANDLED; +} + +enum print_line_t +print_syscall_exit(struct trace_iterator *iter, int flags) +{ + struct trace_seq *s = &iter->seq; + struct trace_entry *ent = iter->ent; + struct syscall_trace_exit *trace; + int syscall; + struct syscall_metadata *entry; + int ret; + + trace_assign_type(trace, ent); + + syscall = trace->nr; + + entry = syscall_nr_to_meta(syscall); + if (!entry) { + trace_seq_printf(s, "\n"); + return TRACE_TYPE_HANDLED; + } + + ret = trace_seq_printf(s, "%s -> 0x%lx\n", entry->name, + trace->ret); + if (!ret) + return TRACE_TYPE_PARTIAL_LINE; + + return TRACE_TYPE_HANDLED; +} + void start_ftrace_syscalls(void) { unsigned long flags; @@ -16,6 +99,7 @@ void start_ftrace_syscalls(void) if (atomic_inc_return(&refcount) != 1) goto out; + arch_init_ftrace_syscalls(); read_lock_irqsave(&tasklist_lock, flags); do_each_thread(g, t) { @@ -48,20 +132,63 @@ out: void ftrace_syscall_enter(struct pt_regs *regs) { + struct syscall_trace_enter *entry; + struct syscall_metadata *sys_data; + struct ring_buffer_event *event; + int size; int syscall_nr; + int cpu; syscall_nr = syscall_get_nr(current, regs); - trace_printk("syscall %d enter\n", syscall_nr); + cpu = raw_smp_processor_id(); + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + size = sizeof(*entry) + sizeof(unsigned long) * sys_data->nb_args; + + event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_ENTER, size, + 0, 0); + if (!event) + return; + + entry = ring_buffer_event_data(event); + entry->nr = syscall_nr; + syscall_get_arguments(current, regs, 0, sys_data->nb_args, entry->args); + + trace_current_buffer_unlock_commit(event, 0, 0); + trace_wake_up(); } void ftrace_syscall_exit(struct pt_regs *regs) { + struct syscall_trace_exit *entry; + struct syscall_metadata *sys_data; + struct ring_buffer_event *event; int syscall_nr; + int cpu; syscall_nr = syscall_get_nr(current, regs); - trace_printk("syscall %d exit\n", syscall_nr); + cpu = raw_smp_processor_id(); + + sys_data = syscall_nr_to_meta(syscall_nr); + if (!sys_data) + return; + + event = trace_current_buffer_lock_reserve(TRACE_SYSCALL_EXIT, + sizeof(*entry), 0, 0); + if (!event) + return; + + entry = ring_buffer_event_data(event); + entry->nr = syscall_nr; + entry->ret = syscall_get_return_value(current, regs); + + trace_current_buffer_unlock_commit(event, 0, 0); + trace_wake_up(); } static int init_syscall_tracer(struct trace_array *tr) @@ -77,17 +204,20 @@ static void reset_syscall_tracer(struct trace_array *tr) } static struct trace_event syscall_enter_event = { - .type = TRACE_SYSCALL_ENTER, + .type = TRACE_SYSCALL_ENTER, + .trace = print_syscall_enter, }; static struct trace_event syscall_exit_event = { - .type = TRACE_SYSCALL_EXIT, + .type = TRACE_SYSCALL_EXIT, + .trace = print_syscall_exit, }; static struct tracer syscall_tracer __read_mostly = { - .name = "syscall", + .name = "syscall", .init = init_syscall_tracer, - .reset = reset_syscall_tracer + .reset = reset_syscall_tracer, + .flags = &syscalls_flags, }; __init int register_ftrace_syscalls(void) -- cgit v1.2.3