Date: Tue, 21 Jan 2003 09:33:06 -0500 (EST) From: Robert Watson <rwatson@FreeBSD.org> To: Alfred Perlstein <alfred@FreeBSD.org> Cc: cvs-committers@FreeBSD.org, cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sys/alpha/alpha busdma_machdep.c src/sys/alpha/osf1 imgact_osf1.c osf1_misc.c src/sys/cam cam_periph.c cam_sim.c cam_xpt.c src/sys/cam/scsi scsi_cd.c scsi_ch.c scsi_da.c scsi_low.c scsi_sa.c scsi_target.c src/sys/coda cnode.h ... Message-ID: <Pine.NEB.3.96L.1030121092713.60586B-100000@fledge.watson.org> In-Reply-To: <200301210856.h0L8uGF3078830@repoman.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Tue, 21 Jan 2003, Alfred Perlstein wrote:
> Log:
> Remove M_TRYWAIT/M_WAITOK/M_WAIT. Callers should use 0.
> Merge M_NOWAIT/M_DONTWAIT into a single flag M_NOWAIT.
Hmm. I guess I missed the discussion; I'm a bit behind on mailing lists.
To improve code portability and careful thinking by developers, what I'd
like to see is something more like the following: M_WAITOK, which
explicitly requests sleeping indefinitely, M_NOWAIT, which explicitly
requests no sleeping. Rather than a "default" value, a
KASSERT(M_WAITOK^M_NOWAIT, ("Bad malloc sleep flags")). With the SMP
kernel work, it's rapidly become clear that we want developers to actually
think about every allocation and sleep case, rather than relying on a
default. One further caveat: with this change, we should be even more
careful to document that M_WAITOK in the case if malloc() will sleep
forever, and that with the mbuf code, you can get back NULL. In principle
though, I think doing this sort of cleanup is a good idea.
Robert N M Watson FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org Network Associates Laboratories
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe cvs-all" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.3.96L.1030121092713.60586B-100000>