From: "David Schwartz" <davids@webmaster.com>
To: "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>
Subject: RE: Why can't we sleep in an ISR?
Date: Tue, 15 May 2007 10:23:34 -0700 [thread overview]
Message-ID: <MDEHLPKNGKAHNMBLJOLKKEBBDNAC.davids@webmaster.com> (raw)
In-Reply-To: <4649E680.9020102@cfl.rr.com>
> No, the term context here has a specific meaning. It refers to those
> things which flow from the current pointer, including the virtual memory
> space, file descriptor table, current uid, and so forth.
And none of these things are used by an ISR.
> Because the
> current pointer is not changed on entry to an ISR, the ISR is executing
> in the context of the interrupted process, and thus uses that process'
> virtual memory, etc.
You mean it would be if it ever looked at the current pointer. It is not the
setting of the current pointer that determines the context but actually
*using* that pointer.
As you said, it is the "things which flow from the current pointer" that
matter, not the value of the pointer itself. An ISR uses none of those
things.
DS
next prev parent reply other threads:[~2007-05-15 17:24 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-05-14 6:37 Learning Linux
[not found] ` <366312910705140010m78b215a2t1753445e81120288@mail.gmail.com>
2007-05-14 7:16 ` Learning Linux
2007-05-14 15:24 ` Bahadir Balban
2007-05-14 15:56 ` Dong Feng
[not found] ` <366312910705142217geba69dbm98a6c0bf2aabb937@mail.gmail.com>
2007-05-15 6:45 ` Dong Feng
[not found] ` <366312910705150010p623f9732mc498f457245d23a1@mail.gmail.com>
2007-05-15 7:28 ` Dong Feng
2007-05-15 8:40 ` Learning Linux
2007-05-15 8:58 ` Dong Feng
2007-05-15 16:57 ` Phillip Susi
2007-05-15 17:23 ` David Schwartz [this message]
2007-05-15 22:49 ` Dong Feng
2007-05-16 15:20 ` Phillip Susi
2007-05-16 23:17 ` Dong Feng
2007-05-17 16:07 ` Phillip Susi
2007-05-17 23:50 ` Dong Feng
2007-05-14 12:25 ` Helge Hafting
[not found] ` <366312910705140552o6a507cbbl806f2ad0efc9d90c@mail.gmail.com>
2007-05-14 13:36 ` Dong Feng
2007-05-14 15:22 linux
2007-05-14 15:55 ` Rik van Riel
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=MDEHLPKNGKAHNMBLJOLKKEBBDNAC.davids@webmaster.com \
--to=davids@webmaster.com \
--cc=linux-kernel@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
all inboxes | Powered by JetHome®