[ltt-dev] Tracing syscall_entry not working

[Venkatesh Babu Chitlur Srinivasa (vchitlur)]

I followed the instructions in 
http://git.lttng.org/?p=lttv.git;a=blob_plain;f=LTTngManual.html#install
lttng to enable the tracing for only the system call enter/exits on
MontaVista kernel. So I loaded only the  ltt-* modules and
syscall-trace.

I did mount debugfs and enabled only syscall enter/exit.

echo 1 > /mnt/debugfs/ltt/markers/kernel/syscall_entry/enable
echo 1 > /mnt/debugfs/ltt/markers/kernel/syscall_exit/enable

lttctl -C -w /tmp/trace1 trace1 trace1

lttctl -D trace1

lttv -mtextDump -t /tmp/trace1

But it is only tracing the syscall exits but not syscall enter.

kernel.syscall_exit: 0.991063935 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 0 }
kernel.syscall_exit: 0.991065411 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 1 }
kernel.syscall_exit: 0.991066830 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 2 }
kernel.syscall_exit: 0.991068682 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 0 }
kernel.syscall_exit: 0.991203430 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 718741504 }
kernel.syscall_exit: 0.991255070 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 0 }
kernel.syscall_exit: 0.991300875 (/tmp/trace1/kernel_3), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 8060 }
kernel.syscall_exit: 0.991322296 (/tmp/trace1/kernel_2), 0, 0, , , 0,
0x0, MODE_UNKNOWN { ret = 0 }

Even when I loaded the all the other trace modules and did ltt-armall,
still I am seeing the traces for only syscall_exit but not for
syscall_enter. Am I missing something here?

Regards,
  VBabu