From 7462911bddd9b5e4033d7108ffc1b6716068f489 Mon Sep 17 00:00:00 2001 From: Tofu Linden Date: Mon, 19 Apr 2010 12:49:15 +0100 Subject: Change Linux fasttimer implementation back to RDTSC - using a reliable syscall was REALLY chewing CPU time. Sigh. I didn't realize how incredibly often this gets called. So, back to the assembly. But be more careful with CPU clock count on linux, so the fasttimer values are much more accurate than they were the last time we were with RDTSC, in absolute terms - back in the right order of magnitude anyway. Also change many instances of Mhz to MHz. Also some minor comment fixes. --- indra/llcommon/llfasttimer.h | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) (limited to 'indra/llcommon/llfasttimer.h') diff --git a/indra/llcommon/llfasttimer.h b/indra/llcommon/llfasttimer.h index 48461df6ae..840d09d970 100644 --- a/indra/llcommon/llfasttimer.h +++ b/indra/llcommon/llfasttimer.h @@ -36,6 +36,10 @@ // pull in the actual class definition #include "llfasttimer_class.h" +// +// Important note: These implementations must be FAST! +// + #if LL_WINDOWS // // Windows implementation of CPU clock @@ -99,15 +103,17 @@ inline U64 LLFastTimer::getCPUClockCount64() #endif -#if LL_LINUX || LL_SOLARIS +#if (LL_LINUX || LL_SOLARIS) && !(defined(__i386__) || defined(__amd64__)) // -// Linux and Solaris implementation of CPU clock - all architectures. +// Linux and Solaris implementation of CPU clock - non-x86. +// This is accurate but SLOW! Only use out of desperation. // // Try to use the MONOTONIC clock if available, this is a constant time counter -// with nanosecond resolution (but not necessarily accuracy) and attempts are made -// to synchronize this value between cores at kernel start. It should not be affected -// by CPU frequency. If not available use the REALTIME clock, but this may be affected by -// NTP adjustments or other user activity affecting the system time. +// with nanosecond resolution (but not necessarily accuracy) and attempts are +// made to synchronize this value between cores at kernel start. It should not +// be affected by CPU frequency. If not available use the REALTIME clock, but +// this may be affected by NTP adjustments or other user activity affecting +// the system time. inline U64 LLFastTimer::getCPUClockCount64() { struct timespec tp; @@ -124,12 +130,12 @@ inline U32 LLFastTimer::getCPUClockCount32() { return (U32)(LLFastTimer::getCPUClockCount64() >> 8); } -#endif // (LL_LINUX || LL_SOLARIS)) +#endif // (LL_LINUX || LL_SOLARIS) && !(defined(__i386__) || defined(__amd64__)) -#if (LL_DARWIN) && (defined(__i386__) || defined(__amd64__)) +#if (LL_LINUX || LL_SOLARIS || LL_DARWIN) && (defined(__i386__) || defined(__amd64__)) // -// Mac x86 implementation of CPU clock +// Mac+Linux+Solaris FAST x86 implementation of CPU clock inline U32 LLFastTimer::getCPUClockCount32() { U64 x; -- cgit v1.2.3