All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Theodore Ts'o" <tytso@mit.edu>
To: George Spelvin <linux@horizon.com>
Cc: hpa@linux.intel.com, price@mit.edu, linux-kernel@vger.kernel.org,
	mingo@kernel.org
Subject: Re: [RFC PATCH] drivers/char/random.c: Is reducing locking range like this safe?
Date: Sun, 8 Jun 2014 21:35:53 -0400	[thread overview]
Message-ID: <20140609013553.GA1167@thunk.org> (raw)
In-Reply-To: <20140609000524.19476.qmail@ns.horizon.com>

On Sun, Jun 08, 2014 at 08:05:24PM -0400, George Spelvin wrote:
> 
> The problem I started trying to solve is readers (entropy extractors)
> monopolizing the pool lock and stalling writers (entropy mixers), which
> are supposed to be fast and low overhead.

Which writer are you worried about, specifically?  A userspace write
to /dev/random from rgnd?

And have you measured this to be something significant, or is this a
theoretical concern.  If you've measured it, what's the conditions
where this is stalling an entropy mixer a significant amount of time?

      	      	       	  	  	  - Ted

  reply	other threads:[~2014-06-09  1:36 UTC|newest]

Thread overview: 57+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-09  0:05 [RFC PATCH] drivers/char/random.c: Is reducing locking range like this safe? George Spelvin
2014-06-09  1:35 ` Theodore Ts'o [this message]
2014-06-09  2:10   ` George Spelvin
2014-06-09  2:18     ` George Spelvin
2014-06-09  4:03       ` George Spelvin
2014-06-09  9:23         ` George Spelvin
2014-06-09 13:34         ` Theodore Ts'o
2014-06-09 15:04           ` George Spelvin
2014-06-09 15:50             ` Theodore Ts'o
2014-06-09 16:11               ` George Spelvin
2014-06-10  0:20               ` drivers/char/random.c: more ruminations George Spelvin
2014-06-10  1:20                 ` Theodore Ts'o
2014-06-10  3:10                   ` George Spelvin
2014-06-10 15:25                     ` Theodore Ts'o
2014-06-10 20:40                       ` George Spelvin
2014-06-10 21:20                         ` Theodore Ts'o
2014-06-11  0:10                           ` George Spelvin
2014-06-11  2:08                             ` Theodore Ts'o
2014-06-11  3:58                               ` George Spelvin
2014-06-11 13:11                                 ` Theodore Ts'o
2014-06-12  0:42                                   ` George Spelvin
2014-06-12  1:03                                   ` H. Peter Anvin
2014-06-11  4:34                               ` George Spelvin
2014-06-11 13:09                                 ` Theodore Ts'o
2014-06-11  2:21                             ` Theodore Ts'o
2014-06-09 13:17   ` drivers/char/random.c: More futzing about George Spelvin
2014-06-11 16:38     ` Theodore Ts'o
2014-06-11 16:48       ` H. Peter Anvin
2014-06-11 19:25         ` Theodore Ts'o
2014-06-11 20:41           ` H. Peter Anvin
2014-06-12  0:44             ` H. Peter Anvin
2014-06-12  1:51               ` George Spelvin
2014-06-12  0:32       ` George Spelvin
2014-06-12  3:22         ` Theodore Ts'o
2014-06-12  4:13           ` random: Benchamrking fast_mix2 George Spelvin
2014-06-12 11:18             ` George Spelvin
2014-06-12 20:17               ` Theodore Ts'o
2014-06-12 20:46               ` Theodore Ts'o
2014-06-13  0:23                 ` George Spelvin
2014-06-13 15:52                   ` Theodore Ts'o
2014-06-14  2:10                     ` George Spelvin
2014-06-14  3:06                       ` Theodore Ts'o
2014-06-14  5:25                         ` George Spelvin
2014-06-14  6:24                           ` Theodore Ts'o
2014-06-14  8:03                             ` George Spelvin
2014-06-14 11:14                               ` George Spelvin
2014-06-14 15:13                                 ` George Spelvin
2014-06-14 16:33                                   ` Theodore Ts'o
2014-06-15  0:23                                     ` George Spelvin
2014-06-15  1:17                                       ` Theodore Ts'o
2014-06-15  6:58                                         ` George Spelvin
2014-06-15 13:01                                           ` Theodore Ts'o
2014-06-14  6:27                           ` Theodore Ts'o
2014-06-14  4:55                     ` [RFC] random: is the IRQF_TIMER test working as intended? George Spelvin
2014-06-14  6:43                       ` Theodore Ts'o
2014-06-14  7:23                         ` George Spelvin
2014-06-12  3:43       ` drivers/char/random.c: More futzing about George Spelvin

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=20140609013553.GA1167@thunk.org \
    --to=tytso@mit.edu \
    --cc=hpa@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@horizon.com \
    --cc=mingo@kernel.org \
    --cc=price@mit.edu \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.