linux-kernel - [RANDOM] Move two variables to read

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <47650FBD.2060209@cosmosbay.com>
Date:	Sun, 16 Dec 2007 12:45:01 +0100
From:	Eric Dumazet <dada1@...mosbay.com>
To:	Matt Mackall <mpm@...enic.com>,
	Andrew Morton <akpm@...ux-foundation.org>
CC:	Linux kernel <linux-kernel@...r.kernel.org>,
	Adrian Bunk <bunk@...nel.org>
Subject: [RANDOM] Move two variables to read_mostly section to save memory

While examining vmlinux namelist on i686, I noticed :

c0581300 D random_table
c0581480 d input_pool
c0581580 d random_read_wakeup_thresh
c0581584 d random_write_wakeup_thresh
c0581600 d blocking_pool

That means that the two integers random_read_wakeup_thresh and 
random_write_wakeup_thresh use a full cache entry (128 bytes).

Moving them to read_mostly section can shrinks vmlinux by 120 bytes.

# size vmlinux*
    text    data     bss     dec     hex filename
4835553  450210  610304 5896067  59f783 vmlinux.after_patch
4835553  450330  610304 5896187  59f7fb vmlinux.before_patch

Signed-off-by: Eric Dumazet <dada1@...mosbay.com>

View attachment "random_read_mostly.patch" of type "text/plain" (763 bytes)