From: Valentin Schneider <valentin.schneider@arm.com>
To: Alexey Dobriyan <adobriyan@gmail.com>,
mingo@redhat.com, peterz@infradead.org
Cc: linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
linux-block@vger.kernel.org, dm-devel@redhat.com,
axboe@kernel.dk, aarcange@redhat.com
Subject: Re: [PATCH] sched: make struct task_struct::state 32-bit
Date: Tue, 3 Sep 2019 18:29:06 +0100 [thread overview]
Message-ID: <d8ad0be1-4ed7-df74-d415-2b1c9a44bac7@arm.com> (raw)
In-Reply-To: <20190902210558.GA23013@avx2>
On 02/09/2019 22:05, Alexey Dobriyan wrote:
> 32-bit accesses are shorter than 64-bit accesses on x86_64.
> Nothing uses 64-bitness of ->state.
>
> Space savings are ~2KB on F30 kernel config.
>
> Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
> ---
>
> arch/ia64/kernel/perfmon.c | 4 ++--
> block/blk-mq.c | 2 +-
> drivers/md/dm.c | 4 ++--
> fs/userfaultfd.c | 2 +-
> include/linux/sched.h | 6 +++---
> include/linux/sched/debug.h | 2 +-
> include/linux/sched/signal.h | 2 +-
> kernel/freezer.c | 2 +-
> kernel/kthread.c | 4 ++--
> kernel/locking/mutex.c | 6 +++---
> kernel/locking/semaphore.c | 2 +-
> kernel/rcu/rcutorture.c | 4 ++--
> kernel/rcu/tree_stall.h | 6 +++---
> kernel/sched/core.c | 8 ++++----
> lib/syscall.c | 2 +-
> 15 files changed, 28 insertions(+), 28 deletions(-)
>
It looks like you missed a few places. There's a long prev_state in
sched/core.c::finish_task_switch() for instance.
I suppose that's where coccinelle oughta help but I'm really not fluent
in that. Is there a way to make it match p.state accesses with p task_struct?
And if so, can we make it change the type of the variable being read from
/ written to?
How did you come up with this changeset, did you pickaxe for some regexp?
[...]
next prev parent reply other threads:[~2019-09-03 17:29 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-09-02 21:05 [PATCH] sched: make struct task_struct::state 32-bit Alexey Dobriyan
2019-09-02 23:02 ` Valentin Schneider
2019-09-03 16:23 ` Alexey Dobriyan
2019-09-03 16:31 ` Valentin Schneider
2019-09-03 6:51 ` [dm-devel] " Christoph Hellwig
2019-09-03 7:13 ` Peter Zijlstra
2019-09-03 17:29 ` Valentin Schneider [this message]
2019-09-03 18:19 ` Alexey Dobriyan
2019-09-03 21:51 ` Valentin Schneider
2019-09-04 12:07 ` Valentin Schneider
2019-09-04 17:48 ` Valentin Schneider
2019-09-05 15:51 ` Markus Elfring
2019-09-05 16:52 ` Valentin Schneider
2019-09-23 10:26 ` Valentin Schneider
2019-09-23 10:34 ` Julia Lawall
2019-09-23 11:26 ` Valentin Schneider
2019-09-23 11:43 ` Julia Lawall
2019-09-23 13:23 ` Valentin Schneider
2019-09-24 8:28 ` Markus Elfring
2019-09-24 8:07 ` Markus Elfring
2019-09-04 9:43 ` [PATCH] " David Laight
2019-09-04 10:25 ` Valentin Schneider
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=d8ad0be1-4ed7-df74-d415-2b1c9a44bac7@arm.com \
--to=valentin.schneider@arm.com \
--cc=aarcange@redhat.com \
--cc=adobriyan@gmail.com \
--cc=axboe@kernel.dk \
--cc=dm-devel@redhat.com \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=peterz@infradead.org \
--cc=rcu@vger.kernel.org \
/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).