• zhangwei(Jovi)'s avatar
    tracing: Fix irqs-off tag display in syscall tracing · 11034ae9
    zhangwei(Jovi) authored
    All syscall tracing irqs-off tags are wrong, the syscall enter entry doesn't
    disable irqs.
    
     [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event
     [root@jovi tracing]# cat trace
     # tracer: nop
     #
     # entries-in-buffer/entries-written: 13/13   #P:2
     #
     #                              _-----=> irqs-off
     #                             / _----=> need-resched
     #                            | / _---=> hardirq/softirq
     #                            || / _--=> preempt-depth
     #                            ||| /     delay
     #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
     #              | |       |   ||||       |         |
           irqbalance-513   [000] d... 56115.496766: sys_open(filename: 804e1a6, flags: 0, mode: 1b6)
           irqbalance-513   [000] d... 56115.497008: sys_open(filename: 804e1bb, flags: 0, mode: 1b6)
             sendmail-771   [000] d... 56115.827982: sys_open(filename: b770e6d1, flags: 0, mode: 1b6)
    
    The reason is syscall tracing doesn't record irq_flags into buffer.
    The proper display is:
    
     [root@jovi tracing]#echo "syscalls:sys_enter_open" > set_event
     [root@jovi tracing]# cat trace
     # tracer: nop
     #
     # entries-in-buffer/entries-written: 14/14   #P:2
     #
     #                              _-----=> irqs-off
     #                             / _----=> need-resched
     #                            | / _---=> hardirq/softirq
     #                            || / _--=> preempt-depth
     #                            ||| /     delay
     #           TASK-PID   CPU#  ||||    TIMESTAMP  FUNCTION
     #              | |       |   ||||       |         |
           irqbalance-514   [001] ....    46.213921: sys_open(filename: 804e1a6, flags: 0, mode: 1b6)
           irqbalance-514   [001] ....    46.214160: sys_open(filename: 804e1bb, flags: 0, mode: 1b6)
                <...>-920   [001] ....    47.307260: sys_open(filename: 4e82a0c5, flags: 80000, mode: 0)
    
    Link: http://lkml.kernel.org/r/1365564393-10972-3-git-send-email-jovi.zhangwei@huawei.com
    
    Cc: stable@vger.kernel.org # 2.6.35
    Signed-off-by: default avatarzhangwei(Jovi) <jovi.zhangwei@huawei.com>
    Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
    11034ae9
trace_syscalls.c 18.5 KB