Subject: Performance measuring in MIPS R3000

From: Chetan B L <[email-masked]>
Date: Thu, 16 Jan 2003 12:01:52 +0530

Hi,
      I want to measure the time taken by any kernel function. 
Is  there anything like rdtsc indtruction in MIPS ?
I saw timepeg patch for measuring the same for Pentium , is there anything
similar to it for MIPS ?

Thanks
Chetan

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From: Florian Lohoff <[email-masked]>
Date: Thu, 16 Jan 2003 16:18:07 +0100

> I saw timepeg patch for measuring the same for Pentium , is there anything

Depending on the CPU - IIRC most R4k variants have something like this
and its sometimes used for generating Timer-Interrupts.

Flo
-- 
Florian Lohoff                  [email-masked]             +49-5201-669912
                        Heisenberg may have been here.

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From: Ralf Baechle <[email-masked]>
Date: Fri, 17 Jan 2003 14:09:02 +0100

> I saw timepeg patch for measuring the same for Pentium , is there anything

The subject of your mail is mentioning the R3000 which doesn't have any
kind of timer in the processor.  As already mentioned in my other posting
do_gettimeofday() is the portable timer interface providing the highest
accuracy.  But the R3000 processor itself doesn't provide any timers so
the precission of the clock will actually depend of the whatever timers
are provided by the rest of the system.  Hoever I doubt you're actually
using a true R3000 - the R3000 is an ~ 1988 vintage processor.  Later
R3000 processors frequently contain a suitable timer.

  Ralf