DragonFly commits List (threaded) for 2005-12
Re: cvs commit: src/sys/i386/i386 mp_machdep.c src/sys/i386/isa clock.c src/sys/kern kern_ktr.c src/sys/sys ktr.h
Matthew Dillon wrote:
dillon 2005/12/06 15:37:55 PST
DragonFly src repository
Synchronize the TSC between all cpus on startup and provide a sysctl,
debug.ktr.resynchronize, which will (very expensively) resynchronize the
TSCs 10 times a second to reduce drift errors to manageable numbers.
The TSC on all the cpus for the purposes of ktrdump's ought to be
synchronizated within ~200ns of each other, assuming all cpus are running
at the same frequency.
This needs more work. What we really need to do is calculate the drift
for each cpu and apply it dynamically.
Revision Changes Path
1.49 +17 -1 src/sys/i386/i386/mp_machdep.c
1.44 +11 -5 src/sys/i386/isa/clock.c
1.7 +98 -2 src/sys/kern/kern_ktr.c
1.8 +1 -1 src/sys/sys/ktr.h
This breaks UP buildkernel here since the extern declaration of
tsc_offsets is inside #ifdef SMP but referenced outside.
I was about to back out the change in ktr_write_entry() but in the end I
wasn't sure enough.