On Mon, Apr 20, 2009 at 03:18:46PM +0800, Wu Zhangjin wrote: > On Mon, 2009-04-20 at 13:04 +0800, Zhang Le wrote: > 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. My git clone is still running to I'm commenting only on the patches you posted earlier. #ifdef-MIPS'ing things into the generic kernel code definately won't be an acceptable way to get µs resolution. Ralf
