On Mon, 2009-04-20 at 13:04 +0800, Zhang Le wrote: > Hi, Zhangjin, > > Ralf told me he has a ftrace implementation too. > > 11:47 < Ralf> r0bertz: ftrace looks nice but not yet mergable yet. > 11:47 < Ralf> r0bertz: I also have my own ftrace implementation which in some > parts is better, in some is worse. > 11:47 < Ralf> r0bertz: So this is going to be quite a job. > > So I think you can talk to Ralf about how to get this merged, :) > to Zhangle, thx very much for your info :-) hope Ralf can reply this E-mail and pull the source code from my git tree: git://dev.lemote.com/rt4ls.git to Ralf, I have divided ftrace to several commits in the above git tree, hope you can check it, thx :-) in addition to the static/dynamic/graph function tracer & system call tracer implementation, a mips specific ring_buffer_time_stamp (kernel/trace/ring_buffer.c) is also implemented to get 1us precision time, this is very important to make ftrace available in mips, otherwise, we can only get 1ms precision time for the original ring_buffer_time_stamp is based on sched_clock(jiffies based). perhaps we can implement a more precise sched_clock directly, just as x86 does(native_sched_clock, tsc based), but in mips, there is only a 32bit timer count which will quickly overflow, so it will need an extra overflow protection, which may influence the other parts of the kernel. best regards, Wu Zhangjin
