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Re: [PATCH v4][BZ 18034][AArch64] Lazy TLSDESC relocation data race fix
- From: Torvald Riegel <triegel at redhat dot com>
- To: Szabolcs Nagy <szabolcs dot nagy at arm dot com>
- Cc: "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>, Marcus Shawcroft <Marcus dot Shawcroft at arm dot com>, Ramana Radhakrishnan <Ramana dot Radhakrishnan at arm dot com>
- Date: Mon, 15 Jun 2015 19:35:09 +0200
- Subject: Re: [PATCH v4][BZ 18034][AArch64] Lazy TLSDESC relocation data race fix
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On Mon, 2015-06-15 at 12:30 +0100, Szabolcs Nagy wrote:
> On 03/06/15 11:40, Torvald Riegel wrote:
> > On Mon, 2015-06-01 at 11:25 +0100, Szabolcs Nagy wrote:
> >> i added a comment to the _dl_tlsdesc_resolve_early_return_p
> >> call in aarch64 tlsdesc.c about the retry loop.
> >
> > That's good, but it would have been better if you could have briefly
> > pointed out that this relates to mo_relaxed loads in
> > _dl_tlsdesc_resolve_early_return_p. And/or added a comment there saying
> > that the mo_relaxed loads are fine because of this retry loop in the
> > caller(s).
> >
> >> - const ElfW(Rela) *reloc = td->arg;
> >> + const ElfW(Rela) *reloc = atomic_load_relaxed (&td->arg);
> >
> > Good change. Can you add a brief comment saying why the mo_relaxed load
> > is sufficient? IIRC, this is because of the acquire loads done by the
> > caller.
> >
> > OK with those changes.
> >
>
> updated the comments in the code and the description:
OK. Thanks!