about syscall again~
"yuanbor" <[email protected]>
| Newsgroups | gmane.linux.kernel.tracing |
|---|---|
| Message-ID | <[email protected]> |
I execute getegid syscall twice, and the trace list below.
What I wanna get is the elapsed time between the time enter the kernel mode and the time return to user mode. According to the trace, I get this time:
[1]the second syscall_entry time - the first syscall_entry time:3265.985720957-3265.985719068=1889
[2]syscall_exit - syscall_entry : 3265.985720157 - 3265.985719068=1089
my question is that whether the syscall_exit time is the time exec flow return from kernel mode to user mode or the time the kernel starts to handle the exit code?
kernel_arch.syscall_entry: 3265.985719068 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { getegid32, -7152 }
locking.hardirqs_off: 3265.985719566 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { 3222293953 }
locking.hardirqs_on: 3265.985719853 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { 3222294237 }
kernel_arch.syscall_exit: 3265.985720157 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, USER_MODE
locking.hardirqs_on: 3265.985720401 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, USER_MODE { 3222294012 }
kernel_arch.syscall_entry: 3265.985720957 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { getegid32, -7152 }
locking.hardirqs_off: 3265.985721336 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { 3222293953 }
locking.hardirqs_on: 3265.985721609 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, SYSCALL { 3222294237 }
kernel_arch.syscall_exit: 3265.985721905 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, USER_MODE
locking.hardirqs_on: 3265.985722148 (/home/yuanbor/trace/syscall/1184337598/cpu_0), 2710, 2710, ./syscall_gettimeofday, UNBRANDED, 2664, 0x0, USER_MODE { 3222294012 }
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