lkml.org 
[lkml]   [2009]   [Aug]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 15/16] tracing: Add fields format definition for syscall events
    Date
    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 <fweisbec@gmail.com>
    Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
    Cc: Steven Rostedt <rostedt@goodmis.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
    Cc: Jiaying Zhang <jiayingz@google.com>
    Cc: Martin Bligh <mbligh@google.com>
    Cc: Li Zefan <lizf@cn.fujitsu.com>
    Cc: Masami Hiramatsu <mhiramat@redhat.com>
    Cc: Jason Baron <jbaron@redhat.com>
    ---
    include/linux/syscalls.h | 1 +
    include/trace/syscall.h | 2 +
    kernel/trace/trace_syscalls.c | 46 +++++++++++++++++++++++++++++++++++++++++
    3 files changed, 49 insertions(+), 0 deletions(-)

    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;
    --
    1.6.2.3


    \
     
     \ /
      Last update: 2009-08-11 20:55    [W:0.025 / U:32.884 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site