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--Zi0sgQQBxRFxMTsj Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sat, Feb 02, 2008 at 09:56:42PM +0200, Alexander Motin wrote: >Peter Jeremy ?????: >> On Sat, Feb 02, 2008 at 11:31:31AM +0200, Alexander Motin wrote: >>> To check UMA dependency I have made a trivial one-element cache which i= n=20 >>> my test case allows to avoid two for four allocations per packet. >>=20 >> You should be able to implement this lockless using atomic(9). I haven't >> verified it, but the following should work. > >I have tried this, but man 9 atomic talks: > >The atomic_readandclear() functions are not implemented for the types >``char'', ``short'', ``ptr'', ``8'', and ``16'' and do not have any=20 >variants with memory barriers at this time. Hmmm. This seems to be more a documentation bug than missing code: atomic_readandclear_ptr() seems to be implemented on most architectures (the only one where I can't find it is arm) and is already used in malloc(3). --=20 Peter Jeremy Please excuse any delays as the result of my ISP's inability to implement an MTA that is either RFC2821-compliant or matches their claimed behaviour. --Zi0sgQQBxRFxMTsj Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFHpNdH/opHv/APuIcRAjglAJ4xNZrFttUitci+60Q+GyVvdziGrQCaAkxf c2uNtF4tELpQ+7FHoc07LLY= =ZYY7 -----END PGP SIGNATURE----- --Zi0sgQQBxRFxMTsj--