From: Arnd Bergmann <arnd@kernel.org>
To: Maninder Singh <maninder1.s@samsung.com>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>,
Nick Desaulniers <ndesaulniers@google.com>,
Jian Cai <caij2003@gmail.com>,
Thomas Gleixner <tglx@linutronix.de>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Marc Zyngier <maz@kernel.org>,
Valentin Schneider <valentin.schneider@arm.com>,
Vincent Whitchurch <vincent.whitchurch@axis.com>,
Nathan Huckleberry <nhuck@google.com>,
Andrew Morton <akpm@linux-foundation.org>,
Dmitry Safonov <0x7f454c46@gmail.com>,
Will Deacon <will@kernel.org>,
v.narang@samsung.com, a.sahrawat@samsung.com,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
Linux ARM <linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH 2/3] arm: introduce IRQ stacks
Date: Wed, 21 Oct 2020 14:42:48 +0200 [thread overview]
Message-ID: <CAK8P3a3eZjBVSuhv=Cx4aYC+E9tex+BbJH1b6YyMMief-mO7kQ@mail.gmail.com> (raw)
In-Reply-To: <CAK8P3a2RYeNiTy9QmwFVKtFifXxWc9XfAT6ThPoSH9wGYsKGpA@mail.gmail.com>
(also resending this reply from @kernel.org)
On Fri, Oct 16, 2020 at 12:19 PM Arnd Bergmann <arnd@arndb.de> wrote:
> On Thu, Oct 8, 2020 at 9:20 AM Maninder Singh <maninder1.s@samsung.com> wrote:
> >
> > This patch adds code for switching to IRQ stack.
> > IRQ stack and Kernel SVC stack have below design.
> >
> > IRQ STACK:-
> > ------------ IRQ stack top
> > | |
> > ------------
> > . .
> > . .
> > . .
> > ------------
> > | sp | <- irq_stack_base + 0x8
> > ------------
> > | fp | <- irq_stack_base + 0x4
> > ------------
> > |tinfo_ptr | /* pointer to thread info */
> > irq_stack_ptr --> ------------ IRQ stack base
> >
> > Kernel SVC stack:-
> > ------------ Kernel stack top
> > | |
> > ------------
> > . .
> > . .
> > . .
> > ------------
> > | |
> > | |
> > ------------
> > |tinfo_ptr | /* pointer to thread info */
> > ------------ Kernel stack base
>
> The extra indirection doesn't look great, and I don't see any of the
> other architectures need that. Since we can access percpu data
> without going through thread_info, maybe doing the same as
> x86 would work here:
>
> - define 'current' as 'this_cpu_read_stable(current_task);'
> - convert to CONFIG_THREAD_INFO_IN_TASK
>
> Arnd
next prev parent reply other threads:[~2020-10-21 12:43 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CGME20201008071628epcas5p24d196a6023a47a3b0bfa7b7f231ec811@epcas5p2.samsung.com>
2020-10-08 7:15 ` [PATCH 0/3] IRQ stack support for ARM Maninder Singh
[not found] ` <CGME20201008071633epcas5p20f5c533ac67ab235997e7e4a8ad3022b@epcas5p2.samsung.com>
2020-10-08 7:15 ` [PATCH 1/3] arm: introduce self pointer in thread info Maninder Singh
[not found] ` <CGME20201008071639epcas5p465f13d992a25936ba63436baf1fb6f83@epcas5p4.samsung.com>
2020-10-08 7:15 ` [PATCH 2/3] arm: introduce IRQ stacks Maninder Singh
[not found] ` <CAK8P3a2RYeNiTy9QmwFVKtFifXxWc9XfAT6ThPoSH9wGYsKGpA@mail.gmail.com>
2020-10-21 12:42 ` Arnd Bergmann [this message]
2020-10-21 12:45 ` Russell King - ARM Linux admin
2020-10-21 12:55 ` Arnd Bergmann
2020-10-21 12:57 ` Russell King - ARM Linux admin
2020-10-21 15:59 ` Arnd Bergmann
2020-11-09 14:45 ` Tony Lindgren
2020-11-09 19:10 ` Arnd Bergmann
2020-11-10 9:19 ` Tony Lindgren
2020-11-10 10:04 ` Arnd Bergmann
2020-11-10 12:04 ` Tony Lindgren
2020-11-10 13:35 ` Arnd Bergmann
2020-11-11 6:56 ` Tony Lindgren
[not found] ` <CGME20201008071639epcas5p465f13d992a25936ba63436baf1fb6f83@epcms5p7>
2020-10-21 13:46 ` Vaneet Narang
[not found] ` <CGME20201008071644epcas5p1f5c220b5f58fd4251695af147325b7c4@epcas5p1.samsung.com>
2020-10-08 7:15 ` [PATCH 3/3] arm: Modify stack trace and dump for use with irq stack Maninder Singh
2020-10-08 7:53 ` [PATCH 0/3] IRQ stack support for ARM Sebastian Andrzej Siewior
2020-10-08 8:30 ` Russell King - ARM Linux admin
2020-10-15 20:59 ` Nick Desaulniers
2020-10-15 21:16 ` Florian Fainelli
[not found] ` <CAK8P3a0h=D8_Kn_fpHbsik_jf4to2jayxj7K7B7=HaNFzKqNnw@mail.gmail.com>
2020-10-21 11:58 ` Arnd Bergmann
2020-10-21 12:34 ` Russell King - ARM Linux admin
2020-10-21 12:46 ` Arnd Bergmann
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='CAK8P3a3eZjBVSuhv=Cx4aYC+E9tex+BbJH1b6YyMMief-mO7kQ@mail.gmail.com' \
--to=arnd@kernel.org \
--cc=0x7f454c46@gmail.com \
--cc=a.sahrawat@samsung.com \
--cc=akpm@linux-foundation.org \
--cc=bigeasy@linutronix.de \
--cc=caij2003@gmail.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@armlinux.org.uk \
--cc=maninder1.s@samsung.com \
--cc=maz@kernel.org \
--cc=ndesaulniers@google.com \
--cc=nhuck@google.com \
--cc=tglx@linutronix.de \
--cc=v.narang@samsung.com \
--cc=valentin.schneider@arm.com \
--cc=vincent.whitchurch@axis.com \
--cc=will@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).