From dc4ddb4c0b7348f1c9759ae8a9e7d734dc1cda82 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Tue, 11 Aug 2009 19:03:54 +0200 Subject: [PATCH] tracing: Add fields format definition for syscall events Define the format of the syscall trace fields to parse the binary values from a raw trace using the syscall events "format" file. This is defined dynamically using the syscalls metadata. It prepares the export of syscall event raw records to perf counters. Example: $ cat /debug/tracing/events/syscalls/sys_enter_sched_getparam/format name: sys_enter_sched_getparam ID: 39 format: field:unsigned short common_type; offset:0; size:2; field:unsigned char common_flags; offset:2; size:1; field:unsigned char common_preempt_count; offset:3; size:1; field:int common_pid; offset:4; size:4; field:int common_tgid; offset:8; size:4; field:pid_t pid; offset:12; size:8; field:struct sched_param * param; offset:20; size:8; print fmt: "pid: 0x%08lx, param: 0x%08lx", ((unsigned long)(REC->pid)), ((unsigned long)(REC->param)) Signed-off-by: Frederic Weisbecker Cc: Lai Jiangshan Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Mathieu Desnoyers Cc: Jiaying Zhang Cc: Martin Bligh Cc: Li Zefan Cc: Masami Hiramatsu Cc: Jason Baron --- include/linux/syscalls.h | 1 + include/trace/syscall.h | 2 ++ kernel/trace/trace_syscalls.c | 46 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 49 insertions(+) diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 5541e75..87d06c1 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -189,6 +189,7 @@ static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \ .system = "syscalls", \ .event = &event_syscall_enter, \ .raw_init = init_enter_##sname, \ + .show_format = ftrace_format_syscall, \ .regfunc = reg_event_syscall_enter, \ .unregfunc = unreg_event_syscall_enter, \ .data = "sys"#sname, \ diff --git a/include/trace/syscall.h b/include/trace/syscall.h index 3ab6dd1..0cb0362 100644 --- a/include/trace/syscall.h +++ b/include/trace/syscall.h @@ -55,6 +55,8 @@ extern int reg_event_syscall_enter(void *ptr); extern void unreg_event_syscall_enter(void *ptr); extern int reg_event_syscall_exit(void *ptr); extern void unreg_event_syscall_exit(void *ptr); +extern int +ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s); 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_syscalls.c b/kernel/trace/trace_syscalls.c index f4eaec3..9ee6386 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -105,6 +105,52 @@ print_syscall_exit(struct trace_iterator *iter, int flags) return TRACE_TYPE_HANDLED; } +int ftrace_format_syscall(struct ftrace_event_call *call, struct trace_seq *s) +{ + int i; + int nr; + int ret = 0; + struct syscall_metadata *entry; + int offset = sizeof(struct trace_entry); + + nr = syscall_name_to_nr((char *)call->data); + entry = syscall_nr_to_meta(nr); + + if (!entry) + return ret; + + for (i = 0; i < entry->nb_args; i++) { + ret = trace_seq_printf(s, "\tfield:%s %s;", entry->types[i], + entry->args[i]); + if (!ret) + return 0; + ret = trace_seq_printf(s, "\toffset:%d;\tsize:%lu;\n", offset, + sizeof(unsigned long)); + if (!ret) + return 0; + offset += sizeof(unsigned long); + } + + trace_seq_printf(s, "\nprint fmt: \""); + for (i = 0; i < entry->nb_args; i++) { + ret = trace_seq_printf(s, "%s: 0x%%0%lulx%s", entry->args[i], + sizeof(unsigned long), + i == entry->nb_args - 1 ? "\", " : ", "); + if (!ret) + return 0; + } + + for (i = 0; i < entry->nb_args; i++) { + ret = trace_seq_printf(s, "((unsigned long)(REC->%s))%s", + entry->args[i], + i == entry->nb_args - 1 ? "\n" : ", "); + if (!ret) + return 0; + } + + return ret; +} + void ftrace_syscall_enter(struct pt_regs *regs, long id) { struct syscall_trace_enter *entry; -- 2.7.4