This is the mail archive of the
mailing list for the glibc project.
Re: Official Linux system wrapper library?
- From: Daniel Colascione <dancol at google dot com>
- To: Joseph Myers <joseph at codesourcery dot com>
- Cc: Szabolcs Nagy <Szabolcs dot Nagy at arm dot com>, Dave P Martin <Dave dot Martin at arm dot com>, nd <nd at arm dot com>, Florian Weimer <fweimer at redhat dot com>, "Michael Kerrisk (man-pages)" <mtk dot manpages at gmail dot com>, linux-kernel <linux-kernel at vger dot kernel dot org>, Joel Fernandes <joelaf at google dot com>, Linux API <linux-api at vger dot kernel dot org>, Willy Tarreau <w at 1wt dot eu>, Vlastimil Babka <vbabka at suse dot cz>, "Carlos O'Donell" <carlos at redhat dot com>, "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>
- Date: Wed, 14 Nov 2018 10:35:42 -0800
- Subject: Re: Official Linux system wrapper library?
- References: <CAKOZuesB4R=dCz4merWQN0FSCGrXmOgUUr4ienSbStBJguNv8g@mail.gmail.com> <email@example.com> <firstname.lastname@example.org> <CAKOZues5SEESpJU=6MDTrPXTA1KTZFGNQE4Lw4t0fO-WBTU62w@mail.gmail.com> <email@example.com> <CAKOZuetdgk1QYhx1538-98rFpogMin=8DkPnCtU9_=ip23Vk7w@mail.gmail.com> <20181113193859.GJ3505@e103592.cambridge.arm.com> <firstname.lastname@example.org> <CAKOZuesta_V=doXsVLc2E6WCQvywdur3F+u2pFKaPN+CEQd+ZQ@mail.gmail.com> <alpine.DEB.email@example.com>
On Wed, Nov 14, 2018 at 10:15 AM, Joseph Myers <firstname.lastname@example.org> wrote:
> feature (e.g. syscall library) with a design coming solely from the kernel
> rather than a cooperative process is also likely to have an unsuitable
> design meaning it doesn't get used.
Is that so? membarrier came directly from the kernel. It gets used and
appears to have a suitable design. That something isn't used by libc
doesn't mean that it doesn't get used in general.
> Once we have sufficient communication
> to design suitable interfaces *together*, "avoiding the need to
> communicate" becomes irrelevant as a design criterion anyway.
If that approach is going to go work, the libc maintainership needs to
be more pragmatic, less idealistic, and less likely to block work on
purity grounds, e.g., we shouldn't do X because the dynamic linker
really should be out-of-process, we can't do Y because nobody should
be using signals, and we can't do Z because the kernel uses IDs that
have such-and-such ugly properties.
A good demonstration of a new commitment to pragmatism would be
merging the trivial wrappers for gettid(2).