From 540b7b8d65575c80162f2a0f38e1d313c92a6042 Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Wed, 19 Aug 2009 15:54:51 +0800 Subject: [PATCH] tracing/syscalls: Add filtering support Add filtering support for syscall events: # echo 'mode == 0666' > events/syscalls/sys_enter_open # echo 'ret == 0' > events/syscalls/sys_exit_open # echo 1 > events/syscalls/sys_enter_open # echo 1 > events/syscalls/sys_exit_open # cat trace ... modprobe-3084 [001] 117.463140: sys_open(filename: 917d3e8, flags: 0, mode: 1b6) modprobe-3084 [001] 117.463176: sys_open -> 0x0 less-3086 [001] 117.510455: sys_open(filename: 9c6bdb8, flags: 8000, mode: 1b6) sendmail-2574 [001] 122.145840: sys_open(filename: b807a365, flags: 0, mode: 1b6) ... Signed-off-by: Li Zefan Cc: Jason Baron Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <4A8BAFCB.1040006@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- include/linux/ftrace_event.h | 5 +++-- include/linux/syscalls.h | 16 +++++++++----- include/trace/syscall.h | 7 ++++++ kernel/trace/trace_events.c | 5 +++-- kernel/trace/trace_syscalls.c | 51 +++++++++++++++++++++++++++++++++++++++---- 5 files changed, 71 insertions(+), 13 deletions(-) diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 427cbae..df5b085 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -140,8 +140,9 @@ extern int filter_current_check_discard(struct ftrace_event_call *call, void *rec, struct ring_buffer_event *event); -extern int trace_define_field(struct ftrace_event_call *call, char *type, - char *name, int offset, int size, int is_signed); +extern int trace_define_field(struct ftrace_event_call *call, + const char *type, const char *name, + int offset, int size, int is_signed); extern int trace_define_common_fields(struct ftrace_event_call *call); #define is_signed_type(type) (((type)(-1)) < 0) diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 8d57f77..f124c89 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -190,6 +190,7 @@ static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ .event = &event_syscall_enter, \ .raw_init = init_enter_##sname, \ .show_format = syscall_enter_format, \ + .define_fields = syscall_enter_define_fields, \ .regfunc = reg_event_syscall_enter, \ .unregfunc = unreg_event_syscall_enter, \ .data = "sys"#sname, \ @@ -226,6 +227,7 @@ static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ .event = &event_syscall_exit, \ .raw_init = init_exit_##sname, \ .show_format = syscall_exit_format, \ + .define_fields = syscall_exit_define_fields, \ .regfunc = reg_event_syscall_exit, \ .unregfunc = unreg_event_syscall_exit, \ .data = "sys"#sname, \ @@ -233,6 +235,8 @@ static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ } #define SYSCALL_METADATA(sname, nb) \ + SYSCALL_TRACE_ENTER_EVENT(sname); \ + SYSCALL_TRACE_EXIT_EVENT(sname); \ static const struct syscall_metadata __used \ __attribute__((__aligned__(4))) \ __attribute__((section("__syscalls_metadata"))) \ @@ -241,20 +245,22 @@ static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ .nb_args = nb, \ .types = types_##sname, \ .args = args_##sname, \ - }; \ - SYSCALL_TRACE_ENTER_EVENT(sname); \ - SYSCALL_TRACE_EXIT_EVENT(sname); + .enter_event = &event_enter_##sname, \ + .exit_event = &event_exit_##sname, \ + }; #define SYSCALL_DEFINE0(sname) \ + SYSCALL_TRACE_ENTER_EVENT(_##sname); \ + SYSCALL_TRACE_EXIT_EVENT(_##sname); \ static const struct syscall_metadata __used \ __attribute__((__aligned__(4))) \ __attribute__((section("__syscalls_metadata"))) \ __syscall_meta_##sname = { \ .name = "sys_"#sname, \ .nb_args = 0, \ + .enter_event = &event_enter__##sname, \ + .exit_event = &event_exit__##sname, \ }; \ - SYSCALL_TRACE_ENTER_EVENT(_##sname); \ - SYSCALL_TRACE_EXIT_EVENT(_##sname); \ asmlinkage long sys_##sname(void) #else #define SYSCALL_DEFINE0(name) asmlinkage long sys_##name(void) diff --git a/include/trace/syscall.h b/include/trace/syscall.h index 5ce85d7..9661dd4 100644 --- a/include/trace/syscall.h +++ b/include/trace/syscall.h @@ -34,6 +34,8 @@ DECLARE_TRACE_WITH_CALLBACK(syscall_exit, * @args: list of args as strings (args[i] matches types[i]) * @enter_id: associated ftrace enter event id * @exit_id: associated ftrace exit event id + * @enter_event: associated syscall_enter trace event + * @exit_event: associated syscall_exit trace event */ struct syscall_metadata { const char *name; @@ -42,6 +44,9 @@ struct syscall_metadata { const char **args; int enter_id; int exit_id; + + struct ftrace_event_call *enter_event; + struct ftrace_event_call *exit_event; }; #ifdef CONFIG_FTRACE_SYSCALLS @@ -59,6 +64,8 @@ extern int syscall_enter_format(struct ftrace_event_call *call, struct trace_seq *s); extern int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s); +extern int syscall_enter_define_fields(struct ftrace_event_call *call); +extern int syscall_exit_define_fields(struct ftrace_event_call *call); enum print_line_t print_syscall_enter(struct trace_iterator *iter, int flags); enum print_line_t print_syscall_exit(struct trace_iterator *iter, int flags); #endif diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 9c7ecfb..79d3520 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -27,8 +27,8 @@ DEFINE_MUTEX(event_mutex); LIST_HEAD(ftrace_events); -int trace_define_field(struct ftrace_event_call *call, char *type, - char *name, int offset, int size, int is_signed) +int trace_define_field(struct ftrace_event_call *call, const char *type, + const char *name, int offset, int size, int is_signed) { struct ftrace_event_field *field; @@ -83,6 +83,7 @@ int trace_define_common_fields(struct ftrace_event_call *call) return ret; } +EXPORT_SYMBOL_GPL(trace_define_common_fields); #ifdef CONFIG_MODULES diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 7336b6c..28e4dae 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -165,6 +165,49 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s) return trace_seq_printf(s, "\nprint fmt: \"0x%%lx\", REC->ret\n"); } +int syscall_enter_define_fields(struct ftrace_event_call *call) +{ + struct syscall_trace_enter trace; + struct syscall_metadata *meta; + int ret; + int nr; + int i; + int offset = offsetof(typeof(trace), args); + + nr = syscall_name_to_nr(call->data); + meta = syscall_nr_to_meta(nr); + + if (!meta) + return 0; + + ret = trace_define_common_fields(call); + if (ret) + return ret; + + for (i = 0; i < meta->nb_args; i++) { + ret = trace_define_field(call, meta->types[i], + meta->args[i], offset, + sizeof(unsigned long), 0); + offset += sizeof(unsigned long); + } + + return ret; +} + +int syscall_exit_define_fields(struct ftrace_event_call *call) +{ + struct syscall_trace_exit trace; + int ret; + + ret = trace_define_common_fields(call); + if (ret) + return ret; + + ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0); + + return ret; +} + void ftrace_syscall_enter(struct pt_regs *regs, long id) { struct syscall_trace_enter *entry; @@ -192,8 +235,8 @@ void ftrace_syscall_enter(struct pt_regs *regs, long id) 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(); + if (!filter_current_check_discard(sys_data->enter_event, entry, event)) + trace_current_buffer_unlock_commit(event, 0, 0); } void ftrace_syscall_exit(struct pt_regs *regs, long ret) @@ -220,8 +263,8 @@ void ftrace_syscall_exit(struct pt_regs *regs, long ret) entry->nr = syscall_nr; entry->ret = syscall_get_return_value(current, regs); - trace_current_buffer_unlock_commit(event, 0, 0); - trace_wake_up(); + if (!filter_current_check_discard(sys_data->exit_event, entry, event)) + trace_current_buffer_unlock_commit(event, 0, 0); } int reg_event_syscall_enter(void *ptr) -- 2.7.4