From: David Miller <davem@davemloft.net>
To: therbert@google.com
Cc: netdev@vger.kernel.org
Subject: Re: [PATCH v3] net: Allow no-cache copy from user on transmit
Date: Fri, 01 Apr 2011 20:52:52 -0700 (PDT) [thread overview]
Message-ID: <20110401.205252.102551587.davem@davemloft.net> (raw)
In-Reply-To: <20110401.204922.28812273.davem@davemloft.net>
From: David Miller <davem@davemloft.net>
Date: Fri, 01 Apr 2011 20:49:22 -0700 (PDT)
> From: Tom Herbert <therbert@google.com>
> Date: Wed, 30 Mar 2011 22:04:32 -0700 (PDT)
>
>> This patch uses __copy_from_user_nocache (from skb_copy_to_page)
>> on transmit to bypass data cache for a performance improvement.
>> This functionality is configurable per device using ethtool.
> ...
>> Signed-off-by: Tom Herbert <therbert@google.com>
>
> It's early in net-next-2.6, so I've applied this now and we can
> add any fixups and tweaks as needed.
Nevermind, you have some work to do in the generic kernel before I
can add this, because nocache copies are not a universally available
feature, for example on sparc64:
In file included from include/linux/tcp.h:210,
from include/linux/ipv6.h:221,
from include/net/ip_vs.h:26,
from kernel/sysctl_binary.c:6:
include/net/sock.h: In function ‘skb_copy_to_page’:
include/net/sock.h:1406: error: implicit declaration of function ‘__copy_from_user_nocache’
make[1]: *** [kernel/sysctl_binary.o] Error 1
make: *** [kernel] Error 2
make: *** Waiting for unfinished jobs....
In file included from include/linux/if_pppox.h:170,
from fs/compat_ioctl.c:38:
include/net/sock.h: In function ‘skb_copy_to_page’:
include/net/sock.h:1406: error: implicit declaration of function ‘__copy_from_user_nocache’
In file included from include/linux/highmem.h:7,
from include/linux/pagemap.h:10,
from include/linux/blkdev.h:12,
from fs/compat_ioctl.c:48:
include/linux/uaccess.h: At top level:
include/linux/uaccess.h:49: error: conflicting types for ‘__copy_from_user_nocache’
include/net/sock.h:1406: note: previous implicit declaration of ‘__copy_from_user_nocache’ was here
next prev parent reply other threads:[~2011-04-02 3:53 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-31 5:04 [PATCH v3] net: Allow no-cache copy from user on transmit Tom Herbert
2011-03-31 8:52 ` Michał Mirosław
2011-04-01 4:05 ` Tom Herbert
2011-04-02 3:49 ` David Miller
2011-04-02 3:52 ` David Miller [this message]
-- strict thread matches above, loose matches on Subject: below --
2011-04-04 4:56 Tom Herbert
2011-04-04 5:03 ` David Miller
2011-04-04 5:23 ` David Miller
2011-04-04 15:10 ` Tom Herbert
2011-04-04 16:52 ` David Miller
2011-04-04 19:44 ` Tom Herbert
2011-04-04 20:05 ` David Miller
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