Re: [PATCH v5 06/12] MIPS: add support for hardware performance events (mipsxx)

[Deng-Cheng Zhu <dengcheng.zhu@gmail.com>]

2010/5/28 David Daney <david.s.daney@gmail.com>:
> General comments:
>
> Can you separate the code that reads and writes the performance counter
> registers from the definitions of the various counters themselves?
[DC]:
1) Do you mean to move M_PERFCTL_* stuff out into pmu.h (or mipsregs.h)?
If yes, that's OK. Again (my reply for [1/12] mentions this for the 1st
time): After making Oprofile use Perf-events as backend (patches 8~12 do
this), register definitions and read/write functions will locate in pmu.h
(or mipsregs.h) and perf_event_$cpu.c, respectively.
2) According to your reply to [7/12], do you mean the perf counter
read/write functions (such as mipsxx_pmu_read_counter()) are generic
support functions? No, they are specific for mipsxx CPUs.


> Also take into account that the counter registers may be either 32 or 64
> bits wide.  The interfaces you are defining should take that into account
> even if the specific implementations only work with 32-bit registers.
[DC]: OK.


Deng-Cheng