From: Florian Weimer <fweimer@redhat.com>
To: "H.J. Lu" <hjl.tools@gmail.com>
Cc: "H.J. Lu via Libc-alpha" <libc-alpha@sourceware.org>
Subject: Re: [PATCH 1/4] x86: Initialize CPU info via IFUNC relocation [BZ 26203]
Date: Mon, 28 Sep 2020 16:47:30 +0200 [thread overview]
Message-ID: <87pn663qm5.fsf@oldenburg2.str.redhat.com> (raw)
In-Reply-To: <CAMe9rOoR_m6L7XUyMBjtqT_c80eiNUjuSOD112iX-Wne6cCYvQ@mail.gmail.com> (H. J. Lu's message of "Mon, 28 Sep 2020 07:39:16 -0700")
* H. J. Lu:
> On Mon, Sep 28, 2020 at 7:22 AM Florian Weimer <fweimer@redhat.com> wrote:
>>
>> * H. J. Lu:
>>
>> > We want to call init_cacheinfo as early as possible. __libc_early_init is
>> > still too late.
>>
>> My point is that we should call it from IFUNC resolvers that need it,
>> and from __libc_early_init. That should cover all cases, no?
>
> Why call it from __libc_early_init after it has been called by
> IFUNC reloc? IFUNC relocations are processed before
> __libc_early_init is called.
IFUNC relocations might not existing in a --disable-multi-arch build,
but it may still need the cacheinfo data if the hard-coded
implementations need them.
We would still run the IFUNC resolver for the artificial IFUNC resolver
with its function pointer, but:
My concern is that you seem to have a specific ordering dependency on
IFUNC resolvers, and I would like to get rid of that: Initialize the
necessary data on demand (for string function selection), and during
__libc_early_init for potential use from string functions.
I hope this clarifies what I'm looking for. Please let me know if this
is not reasonable.
Thanks,
Florian
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next prev parent reply other threads:[~2020-09-28 14:47 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-09-18 16:07 V2 [PATCH 0/4] ld.so: Add --list-tunables to print tunable values H.J. Lu
2020-09-18 16:07 ` [PATCH 1/4] x86: Initialize CPU info via IFUNC relocation [BZ 26203] H.J. Lu
2020-09-28 13:08 ` Florian Weimer
2020-09-28 13:48 ` H.J. Lu
2020-09-28 14:05 ` Florian Weimer
2020-09-28 14:20 ` H.J. Lu
2020-09-28 14:22 ` Florian Weimer
2020-09-28 14:39 ` H.J. Lu
2020-09-28 14:47 ` Florian Weimer [this message]
2020-09-28 17:54 ` V3 [PATCH] " H.J. Lu
2020-09-29 7:53 ` Florian Weimer
2020-09-29 11:44 ` H.J. Lu
2020-10-01 8:46 ` Florian Weimer
2020-10-01 19:50 ` V4 " H.J. Lu
2020-10-08 13:22 ` PING: " H.J. Lu
2020-10-15 12:53 ` PING^2: " H.J. Lu
2022-05-02 13:59 ` Sunil Pandey
2022-05-03 18:51 ` Sunil Pandey
2020-09-18 16:07 ` [PATCH 2/4] Set tunable value as well as min/max values H.J. Lu
2020-09-28 13:35 ` Florian Weimer
2020-09-28 13:53 ` H.J. Lu
2020-09-28 14:03 ` Florian Weimer
2020-09-28 17:30 ` Siddhesh Poyarekar
2020-09-29 4:00 ` V3 [PATCH] " H.J. Lu
2020-09-29 4:45 ` Siddhesh Poyarekar
2020-09-29 4:47 ` Siddhesh Poyarekar
2020-09-29 12:30 ` V4 " H.J. Lu
2020-09-29 13:50 ` Siddhesh Poyarekar
2020-09-29 14:54 ` V5 " H.J. Lu
2020-09-29 15:58 ` Siddhesh Poyarekar
2020-09-18 16:07 ` [PATCH 3/4] x86: Move x86 processor cache info to cpu_features H.J. Lu
2020-09-18 16:07 ` [PATCH 4/4] ld.so: Add --list-tunables to print tunable values H.J. Lu
2020-09-21 8:25 ` Florian Weimer
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