linux-acpi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Alexey Starikovskiy <aystarik@gmail.com>
To: Pavel Machek <pavel@ucw.cz>
Cc: Xiaotian Feng <dfeng@redhat.com>,
	lenb@kernel.org, ming.m.lin@intel.com, robert.moore@intel.com,
	linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ACPICA: don't cond_resched() when irq_disabled or in_atomic
Date: Thu, 10 Dec 2009 21:37:59 +0300	[thread overview]
Message-ID: <4B214007.2080409@gmail.com> (raw)
In-Reply-To: <20091210181800.GM19454@elf.ucw.cz>

Pavel Machek пишет:
> On Thu 2009-12-10 20:58:45, Alexey Starikovskiy wrote:
>   
>> Hi Pavel,
>>
>> Please elaborate... Your comments "ugly as hell" are too often to be
>> specific...
>> There is only one use of ACPI_PREEMPTION_POINT(), and it is in the
>> ACPICA code,
>> which we all agreed to keep OS independent, thus the need for #define.
>> Do you see any other way to add preemption point without introducing
>> Linux-specific
>> code into ACPICA?
>>     
>
> I believe we want linux-specific code in acpica at this point.
>
>   
The point there we call cond_resched() in ACPICA is an interpreter parse
loop. This parse loop may be executed from within atomic context and even
with interrupts off. In this case, cond_resched() should not be called
to not make
might_sleep() guards angry.

Please post the code, which will do the above and will not look "ugly as
hell".
I still don't follow your vague comments.
> (Or maybe... I guess other systems have concept of preemption and not
> all actions are permitted from all contexts, so maybe something like
> that would be important for them, too?)
>   
None of them cared about it up to this point.
With the macro above we allowed them to follow Linux, but to go or not
is their call.

Regards,
Alex.
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

  reply	other threads:[~2009-12-10 18:37 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-12-04  4:26 [PATCH] ACPICA: don't cond_resched() when irq_disabled or in_atomic Xiaotian Feng
2009-12-04  5:36 ` Zhang Rui
2009-12-04  5:38   ` Zhang Rui
2009-12-04  6:50 ` Justin Mattock
2009-12-04  7:05   ` Danny Feng
2009-12-04  7:27     ` Justin P. Mattock
2009-12-09  1:54       ` Xiaotian Feng
2009-12-10 10:09 ` Pavel Machek
2009-12-10 11:56   ` [PATCH -V2] acpi: don't cond_resched if irq is disabled Xiaotian Feng
2009-12-10 12:21     ` Alexey Starikovskiy
2009-12-11  5:46       ` Lin Ming
2009-12-11 11:48         ` Alexey Starikovskiy
2009-12-11 16:15           ` Pavel Machek
2009-12-11 16:25             ` Alexey Starikovskiy
2009-12-11 17:34               ` Pavel Machek
2009-12-28  6:02                 ` Xiaotian Feng
2009-12-28 11:12                   ` Alexey Starikovskiy
2010-01-16  6:44                     ` Len Brown
2009-12-10 17:58   ` [PATCH] ACPICA: don't cond_resched() when irq_disabled or in_atomic Alexey Starikovskiy
2009-12-10 18:18     ` Pavel Machek
2009-12-10 18:37       ` Alexey Starikovskiy [this message]
2009-12-10 22:46         ` Justin P. Mattock
2009-12-10 22:54           ` Moore, Robert
2010-01-16  6:46             ` Len Brown
2009-12-11 17:33         ` Pavel Machek

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=4B214007.2080409@gmail.com \
    --to=aystarik@gmail.com \
    --cc=dfeng@redhat.com \
    --cc=lenb@kernel.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=ming.m.lin@intel.com \
    --cc=pavel@ucw.cz \
    --cc=robert.moore@intel.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).