linux-kernel - Re: [PATCH 5/7] Alter get_order() so that it can make use of ilog2() on a constant [try #3]

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20060919080324.601e50f9.akpm@osdl.org>
Date:	Tue, 19 Sep 2006 08:03:24 -0700
From:	Andrew Morton <akpm@...l.org>
To:	David Howells <dhowells@...hat.com>
Cc:	torvalds@...l.org, linux-kernel@...r.kernel.org,
	linux-arch@...r.kernel.org
Subject: Re: [PATCH 5/7] Alter get_order() so that it can make use of
 ilog2() on a constant [try #3]

On Tue, 19 Sep 2006 10:08:17 +0100
David Howells <dhowells@...hat.com> wrote:

> > I didn't pursue it further, because sprinkling ARCH_HAS_FOO things into
> > bitops.h(!) is all rather hacky.  Better to use CONFIG_* so they're always
> > visible and one knows where to go to find things.
> 
> But (1) they're not config options,

Well they are, really.  "This architecture has its own get_order()".  It's
not *user* configurable, but neither is, say CONFIG_GENERIC_HARDIRQS.

The problem we have with the ARCH_HAS_FOO things is that there's never been
an include/asm/arch_has_foo.h in which to define them, so stuff gets
sprinkled all over the place.

> and (2) there's plenty of precedent for
> this sort of thing (ARCH_HAS_PREFETCH for example).

There's precedent both ways.  The advantages of doing it in config are

a) You know where to go to find it: arch/foo/Kconfig

b) It's always available, due to forced inclusion of config.h.

(I think I actually would prefer include/asm/arch_has_foo.h if we had it,
because it's lighter-weight.  But we don't)
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/