Messages in this thread | | | Date | Sun, 14 Jun 2009 14:53:09 +0300 | From | Avi Kivity <> | Subject | Re: [PATCH 1/2] lib: Provide generic atomic64_t implementation |
| |
Linus Torvalds wrote: > On Sat, 13 Jun 2009, Linus Torvalds wrote: > >> On Sat, 13 Jun 2009, Paul Mackerras wrote: >> >>> Linus, Andrew: OK if this goes in via the powerpc tree? >>> >> Ok by me. >> > > Btw, do 32-bit architectures really necessarily want 64-bit performance > counters? > > I realize that 32-bit counters will overflow pretty easily, but I do > wonder about the performance impact of doing things like hashed spinlocks > for 64-bit counters. Maybe the downsides of 64-bit perf counters on such > architectures might outweight the upsides? >
An alternative implementation using 64-bit cmpxchg will recover most of the costs of hashed spinlocks. I assume most serious 32-bit architectures have them?
-- error compiling committee.c: too many arguments to function
| |