From: Palmer Dabbelt <palmer@dabbelt.com>
To: bjorn@kernel.org, ndesaulniers@google.com, nathan@kernel.org
Cc: Conor Dooley <conor@kernel.org>,
jszhang@kernel.org, llvm@lists.linux.dev,
Paul Walmsley <paul.walmsley@sifive.com>,
aou@eecs.berkeley.edu, Arnd Bergmann <arnd@arndb.de>,
linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org,
linux-arch@vger.kernel.org
Subject: Re: [PATCH v2 0/4] riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION
Date: Wed, 21 Jun 2023 11:19:31 -0700 (PDT) [thread overview]
Message-ID: <mhng-1d790a82-44ad-4b9c-bfe4-6303f09b0705@palmer-ri-x1c9a> (raw)
In-Reply-To: <87wmzwn1po.fsf@all.your.base.are.belong.to.us>
On Wed, 21 Jun 2023 10:51:15 PDT (-0700), bjorn@kernel.org wrote:
> Conor Dooley <conor@kernel.org> writes:
>
> [...]
>
>>> So I'm no longer actually sure there's a hang, just something slow.
>>> That's even more of a grey area, but I think it's sane to call a 1-hour
>>> link time a regression -- unless it's expected that this is just very
>>> slow to link?
>>
>> I dunno, if it was only a thing for allyesconfig, then whatever - but
>> it's gonna significantly increase build times for any large kernels if LLD
>> is this much slower than LD. Regression in my book.
>>
>> I'm gonna go and experiment with mixed toolchain builds, I'll report
>> back..
>
> I took palmer/for-next (1bd2963b2175 ("Merge patch series "riscv: enable
> HAVE_LD_DEAD_CODE_DATA_ELIMINATION"")) for a tuxmake build with llvm-16:
>
> | ~/src/tuxmake/run -v --wrapper ccache --target-arch riscv \
> | --toolchain=llvm-16 --runtime docker --directory . -k \
> | allyesconfig
>
> Took forever, but passed after 2.5h.
Thanks. I just re-ran mine 17/trunk LLD under time (rather that just
checking top sometimes), it's at 1.5h but even that seems quite long.
I guess this is sort of up to the LLVM folks: if it's expected that DCE
takes a very long time to link then I'm not opposed to allowing it, but
if this is probably a bug in LLD then it seems best to turn it off until
we sort things out over there.
I think maybe Nick or Nathan is the best bet to know?
> CONFIG_CC_VERSION_TEXT="Debian clang version 16.0.6 (++20230610113307+7cbf1a259152-1~exp1~20230610233402.106)"
>
>
> Björn
next prev parent reply other threads:[~2023-06-21 18:20 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-05-23 16:54 [PATCH v2 0/4] riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION Jisheng Zhang
2023-05-23 16:54 ` [PATCH v2 1/4] riscv: move options to keep entries sorted Jisheng Zhang
2023-05-25 14:01 ` Conor Dooley
2023-06-01 4:48 ` Guo Ren
2023-05-23 16:55 ` [PATCH v2 2/4] riscv: vmlinux-xip.lds.S: remove .alternative section Jisheng Zhang
2023-06-01 4:43 ` Guo Ren
2023-05-23 16:55 ` [PATCH v2 3/4] vmlinux.lds.h: use correct .init.data.* section name Jisheng Zhang
2023-05-24 11:02 ` Kefeng Wang
2023-05-23 16:55 ` [PATCH v2 4/4] riscv: enable HAVE_LD_DEAD_CODE_DATA_ELIMINATION Jisheng Zhang
2023-05-24 11:04 ` Kefeng Wang
2023-06-14 14:49 ` [PATCH v2 0/4] " Palmer Dabbelt
2023-06-14 16:25 ` Jisheng Zhang
2023-06-15 13:54 ` Palmer Dabbelt
2023-06-19 22:06 ` Palmer Dabbelt
2023-06-20 20:05 ` Nick Desaulniers
2023-06-20 20:13 ` Conor Dooley
2023-06-20 20:32 ` Nick Desaulniers
2023-06-20 20:41 ` Palmer Dabbelt
2023-06-20 20:47 ` Nick Desaulniers
2023-06-20 21:08 ` Palmer Dabbelt
2023-06-21 0:13 ` Palmer Dabbelt
2023-06-21 14:53 ` Palmer Dabbelt
2023-06-21 16:42 ` Conor Dooley
2023-06-21 17:23 ` Conor Dooley
2023-06-21 17:51 ` Björn Töpel
2023-06-21 18:19 ` Palmer Dabbelt [this message]
2023-06-21 19:46 ` Palmer Dabbelt
2023-06-22 21:40 ` Nick Desaulniers
2023-06-22 21:42 ` Palmer Dabbelt
2023-06-22 21:53 ` Nathan Chancellor
2023-06-22 22:16 ` Palmer Dabbelt
2023-06-22 23:18 ` Nathan Chancellor
2023-06-23 17:17 ` Nick Desaulniers
2023-06-25 12:24 ` Jisheng Zhang
2023-06-25 12:43 ` Conor Dooley
2023-06-25 20:05 ` Palmer Dabbelt
2023-06-25 20:06 ` Palmer Dabbelt
2023-07-22 0:37 ` Fangrui Song
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=mhng-1d790a82-44ad-4b9c-bfe4-6303f09b0705@palmer-ri-x1c9a \
--to=palmer@dabbelt.com \
--cc=aou@eecs.berkeley.edu \
--cc=arnd@arndb.de \
--cc=bjorn@kernel.org \
--cc=conor@kernel.org \
--cc=jszhang@kernel.org \
--cc=linux-arch@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-riscv@lists.infradead.org \
--cc=llvm@lists.linux.dev \
--cc=nathan@kernel.org \
--cc=ndesaulniers@google.com \
--cc=paul.walmsley@sifive.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).