fxzhang <[email protected]> writes: Hi Fuxhin !
> Arnaud Patard (Rtp) 写道: >> Laurent GUERBY <[email protected]> writes: >> >> >>> Hi, >>> >> >> Hi, >> >> >>> I'd like to time some low level code, is there a way >>> to count cycles in userspace for loongson processors >>> running debian lenny? >>> >> >> You can try using the mips instruction rdhwr to get the cycle counter. I >> didn't tested it but I think it should work. >> > As far as I know, there is still no rdhwr instruction in LS2E/2F, but If the hardware doesn't support the rdhwr instruction, the kernel emulates it. I know it emulate the register needed for the tls thread_area but I didn't check for the cp0 counter. I hope it's implemented /o\ > you can use mfc0/dmfc0 to read the 'count' cp0 register. afaik these instructions can't be used in userspace. Arnaud -- To UNSUBSCRIBE, email to [email protected] with a subject of "unsubscribe". Trouble? Contact [email protected]
