This is the mail archive of the
mailing list for the glibc project.
Re: [RFC][PATCH 0/2] Make sparcv8 work again on cas enabled hardware
- From: Torvald Riegel <triegel at redhat dot com>
- To: David Miller <davem at davemloft dot net>
- Cc: andreas at gaisler dot com, libc-alpha at sourceware dot org, adhemerval dot zanella at linaro dot org, carlos at redhat dot com, software at gaisler dot com
- Date: Wed, 02 Nov 2016 23:33:03 +0100
- Subject: Re: [RFC][PATCH 0/2] Make sparcv8 work again on cas enabled hardware
- Authentication-results: sourceware.org; auth=none
- References: <firstname.lastname@example.org> <email@example.com> <firstname.lastname@example.org> <email@example.com>
On Wed, 2016-11-02 at 11:32 -0400, David Miller wrote:
> From: Torvald Riegel <firstname.lastname@example.org>
> > Or do you intend to write sparc-specific versions of all the concurrent
> > data structures that are process-shared?
> This would be necessary anyways, if we have two modes. One that does
> the pure-userland code path and one that does the kernel helper code
All the other archs that use a kernel helper for CAS don't need it. If
you can call the helper in the atomic operations, you won't need a new
algorithm except if you wanted to optimize the generic one.
> Furthermore, sparc specific versions are needed in any case since we
> have the v9 detection even in the v8 libraries. Look at all of the
> code that checks for v9 in the dl_hwcap mask when deciding which
> atomic operation to use.
Or are you talking about the implementation of the atomic operations?