Re: CVS commit: src/sys/arch/sparc/sparc
On Sun, Nov 04, 2012 at 01:35:04PM +1100, matthew green wrote: > > > Module Name:src > > Committed By: chs > > Date: Sun Nov 4 00:32:47 UTC 2012 > > > > Modified Files: > > src/sys/arch/sparc/sparc: locore.s pmap.c > > > > Log Message: > > in cpu_switchto(), remove the MP-unsafe code to mark a pmap active on a CPU, > > pmap_activate() already does this. add MP locking to pmap_activate() > > and pmap_deactivate(). move flushing of user windows and virtual caches > > from pamp_activate() to pmap_deactivate(). > > > hmm. this makes pmap_deactivate() do things in UP that weren't being > done before at all. switching to/from kernel/lwp for the same lwp will > now be flushing the ctx every time. that seems suboptimal? do you just mean that I should have left the #ifdef MULTIPROCESSOR around the sp_tlb_flush()? or something more than that? > we should really update PMAP_LOCK() to not be kernel lock. agreed. beyond that, there's still plenty of room for improvement on most platforms. I think the best example in our tree at this point is the x86 scheme of deferring the MMU-switch work to points where we're actually about to reference user mappings, eg. returning to user mode, copyin/copyout, etc. -Chuck
Re: CVS commit: xsrc/external/mit/libpciaccess/dist/src
On Nov 4, 2012, at 2:26 AM, David Laight wrote:
> Personally I almost never mark variables 'const', the only I initialise
> in their declarations (at the top of a function) are probably almost
> always never chaned (well maybe execpt default error values).
Personally, I always mark variable as const if I don't expect its value to
change since that documents that expectation. This is especially true for
pointers:
const struct foo_softc * const sc = ifp->if_softc;
Once nice side effect is that it catches errors like:
if (sc = NULL) {
}
Re: CVS commit: xsrc/external/mit/libpciaccess/dist/src
On Sun, Nov 04, 2012 at 08:44:01AM +0200, Alan Barrett wrote: > On Fri, 02 Nov 2012, David Young wrote: > >>Modified Files: > >>xsrc/external/mit/libpciaccess/dist/src: common_interface.c > >> > >>Log Message: > >>Remove useless extra "const" in "const sometype const * var = value;". > >>Foundusing clang -Wduplicate-decl-specifier. > > > >Maybe 'const sometype * const var' was intended, i.e., a "single > >assignment" semantic? I've probably mistyped that myself several times. > > The variable is assigned only once, so that would work, > but it's in a small block where I don't think it would add any clarity. Personally I almost never mark variables 'const', the only I initialise in their declarations (at the top of a function) are probably almost always never chaned (well maybe execpt default error values). Marking function parameters 'const' is also pointless, some compilers verify that the definition in the headers file matches - which is partitularly pointless since the called object code isn't required to avoid modifying the argument memory/register (which might sometimes be a useful optimistation). David -- David Laight: da...@l8s.co.uk
