[kgtp] KGTP (Linux Kernel debugger and tracer) 20120319 release(include hotcode analyzer hotcode.py)
- From: Hui Zhu <teawater@xxxxxxxxx>
- To: linux-kernel@xxxxxxxxxxxxxxx, "gdb@xxxxxxxxxxxxxx" <gdb@xxxxxxxxxxxxxx>, kgtp <kgtp@xxxxxxxxxxxxx>
- Date: Mon, 19 Mar 2012 16:50:54 +0800
KGTP is a realtime and lightweight Linux Kernel debugger and tracer.
It makes Linux Kernel supply a GDB remote debug interface. Then GDB in
current machine or remote machine (see
https://code.google.com/p/kgtp/wiki/HOWTO#Make_GDB_connect_to_gtp) can
debug and trace Linux through GDB tracepoint without stopping the
Linux Kernel. And even if the board doesn't have GDB on it and doesn't
have interface for remote debug. It can debug the Linux Kernel using
offline debug (See
https://code.google.com/p/kgtp/wiki/HOWTO#Offline_debug).
And it can work with Android (See
https://code.google.com/p/kgtp/wiki/HowToUseKGTPinAndroid).
Now, it supports X86-32, X86-64, MIPS and ARM.
Now, KGTP 20120319 release.
You can get the package for it from
http://kgtp.googlecode.com/files/kgtp_20120319.tar.bz2
or
svn co https://kgtp.googlecode.com/svn/tags/20120319
When 20120224 release, I said that I just work on a very interesting
add-ons(a python script for GDB). Now, it is included in the KGTP and
named hotcode.py.
It can show the hotest code line in the Kernel or user space program
without interrupt them through parse and record the pc address in the
irq handler.
Following part is a output of hotcode.py:
sudo gdb ./vmlinux -x ~/kernel/svn/trunk/add-ons/hotcode.py
task 17502 /home/teawater/kernel/svn/bak/a.out
Kernel hotcode:
Hotest function
format_decode 68
string 51
__ticket_spin_lock 27
vsnprintf 25
memcpy 25
mutex_lock 19
mutex_unlock 18
system_call 18
copy_user_generic_string 18
strnlen 17
seq_read 15
fget_light 8
__ticket_spin_unlock 8
None 6
sys_lseek 4
rw_verify_area 4
proc_reg_read 4
vfs_read 4
fsnotify 3
seq_printf 3
Hotest file
/home/teawater/kernel2/linux/lib/vsprintf.c 144
/home/teawater/kernel2/linux/arch/x86/include/asm/spinlock.h
35
/home/teawater/kernel2/linux/kernel/mutex.c 35
/home/teawater/kernel2/linux/arch/x86/lib/memcpy_64.S 25
/home/teawater/kernel2/linux/fs/seq_file.c 21
/home/teawater/kernel2/linux/arch/x86/lib/copy_user_64.S
18
/home/teawater/kernel2/linux/arch/x86/kernel/entry_64.S
18
/home/teawater/kernel2/linux/lib/string.c 17
/home/teawater/kernel2/linux/fs/read_write.c 16
/home/teawater/kernel2/linux/fs/proc/inode.c 6
None 6
/home/teawater/kernel2/linux/fs/notify/fsnotify.c 5
/home/teawater/kernel2/linux/fs/file_table.c 5
/home/teawater/kernel2/linux/include/linux/fdtable.h 3
/home/teawater/kernel2/linux/arch/x86/include/asm/paravirt.h
2
/home/teawater/kernel2/linux/include/linux/spinlock.h 2
/home/teawater/kernel2/linux/kernel/mutex.h 2
/home/teawater/kernel2/linux/include/linux/proc_fs.h 2
/home/teawater/kernel2/linux/kernel/sched/core.c 1
/home/teawater/kernel2/linux/include/linux/file.h 1
Hotest line
/home/teawater/kernel2/linux/lib/vsprintf.c:983 32
/home/teawater/kernel2/linux/arch/x86/include/asm/spinlock.h:57
26
/home/teawater/kernel2/linux/lib/vsprintf.c:395 24
/home/teawater/kernel2/linux/kernel/mutex.c:124 18
/home/teawater/kernel2/linux/kernel/mutex.c:90 15
/home/teawater/kernel2/linux/lib/string.c:402 15
/home/teawater/kernel2/linux/arch/x86/kernel/entry_64.S:477
14
/home/teawater/kernel2/linux/arch/x86/lib/memcpy_64.S:73
13
/home/teawater/kernel2/linux/lib/vsprintf.c:982 11
/home/teawater/kernel2/linux/lib/vsprintf.c:394 10
/home/teawater/kernel2/linux/arch/x86/include/asm/spinlock.h:84
8
/home/teawater/kernel2/linux/lib/vsprintf.c:957 8
/home/teawater/kernel2/linux/arch/x86/lib/memcpy_64.S:75
7
/home/teawater/kernel2/linux/arch/x86/lib/copy_user_64.S:250
7
None:None 6
/home/teawater/kernel2/linux/lib/vsprintf.c:377 6
/home/teawater/kernel2/linux/lib/vsprintf.c:1015 5
/home/teawater/kernel2/linux/arch/x86/lib/memcpy_64.S:67
5
/home/teawater/kernel2/linux/lib/vsprintf.c:1132 5
/home/teawater/kernel2/linux/fs/seq_file.c:258 5
User hotcode:
Hotest function
/lib/libc-2.12.1.so:lseek64 11
/home/teawater/kernel/svn/bak/a.out:main 6
/lib/libc-2.12.1.so:read 6
None 1
Hotest file
None 18
readc.c 6
Hotest line
None:None 18
readc.c:87 2
readc.c:83 2
readc.c:81 1
readc.c:85 1
It can show the hot functions, hot files and hot lines. Even if some
functions is inside libs, it can parser the info out.
And hotcode.py can monitor a lot of tasks in same time.
And I will add GUI to this add-ons to make it can outout infor more clear.
The other change of this release is:
Fix bug with GDB RSP package sum check.
Increase the speed of access to trace state variables.
Increase the speed of agent code execution.
Remove the current agent code "printf" support because GDB will
support new format of agent code "printf".
Fix bug about access $current_task_pid.
Add new debug switch GTP_DEBUG_V (just for developer).
To get other change info please goto https://code.google.com/p/kgtp/wiki/UPDATE
According to the comments of Christoph. I make a patch for Linux
Kernel and make it looks OK with checkpatch.pl. I will post the patch
for review to linux-kernel@xxxxxxxxxxxxxxx in a separate mail.
Thanks,
Hui
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- » [kgtp] KGTP (Linux Kernel debugger and tracer) 20120319 release(include hotcode analyzer hotcode.py) - Hui Zhu
