On Mon, Apr 20, 2009 at 10:01:55AM +0200, Ralf Baechle wrote: > > 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. In changeset e67f78d663a84ef93aa12c3c8c1adf3033c4f9a1 you introduce <asm/rwsem.h> but because RWSEM_GENERIC_SPINLOCK is always set that file won't ever be included. Ralf
