linux/arch/m68k
Neil Horman 3b885787ea net: Generalize socket rx gap / receive queue overflow cmsg
Create a new socket level option to report number of queue overflows

Recently I augmented the AF_PACKET protocol to report the number of frames lost
on the socket receive queue between any two enqueued frames.  This value was
exported via a SOL_PACKET level cmsg.  AFter I completed that work it was
requested that this feature be generalized so that any datagram oriented socket
could make use of this option.  As such I've created this patch, It creates a
new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a
SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue
overflowed between any two given frames.  It also augments the AF_PACKET
protocol to take advantage of this new feature (as it previously did not touch
sk->sk_drops, which this patch uses to record the overflow count).  Tested
successfully by me.

Notes:

1) Unlike my previous patch, this patch simply records the sk_drops value, which
is not a number of drops between packets, but rather a total number of drops.
Deltas must be computed in user space.

2) While this patch currently works with datagram oriented protocols, it will
also be accepted by non-datagram oriented protocols. I'm not sure if thats
agreeable to everyone, but my argument in favor of doing so is that, for those
protocols which aren't applicable to this option, sk_drops will always be zero,
and reporting no drops on a receive queue that isn't used for those
non-participating protocols seems reasonable to me.  This also saves us having
to code in a per-protocol opt in mechanism.

3) This applies cleanly to net-next assuming that commit
977750076d (my af packet cmsg patch) is reverted

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-10-12 13:26:31 -07:00
..
amiga m68k: cnt reaches -1, not 0 2009-08-26 23:14:49 +02:00
apollo m68k: apollo core - Kill warn_unused_result warnings 2009-01-12 20:56:35 +01:00
atari m68k: atari - Rename "mfp" to "st_mfp" 2009-02-22 09:23:02 -08:00
bvme6000 m68k: Kill several external declarations in source files 2009-01-12 20:56:34 +01:00
configs m68k: Update defconfigs for 2.6.30-rc3 2009-04-22 20:55:12 +02:00
fpsp040 m68k: fix trigraph ignored warning in setox.S 2008-12-28 20:00:05 +01:00
hp300 m68k: hp300 core - Kill warn_unused_result warnings 2009-01-12 20:56:36 +01:00
ifpsp060 Stringify support commas 2008-07-20 17:24:38 -07:00
include/asm net: Generalize socket rx gap / receive queue overflow cmsg 2009-10-12 13:26:31 -07:00
kernel headers: utsname.h redux 2009-09-23 18:13:10 -07:00
lib Stringify support commas 2008-07-20 17:24:38 -07:00
mac m68k: mac - Add SWIM floppy support 2009-03-26 21:15:27 +01:00
math-emu locking, m68k/asm-offsets: Rename signal defines 2009-09-01 09:38:03 +02:00
mm arches: drop superfluous casts in nr_free_pages() callers 2009-09-22 07:17:34 -07:00
mvme16x m68k: Kill several external declarations in source files 2009-01-12 20:56:34 +01:00
mvme147 m68k: mvme147 core - Kill warn_unused_result warnings 2009-01-12 20:56:37 +01:00
q40 m68k: Kill several external declarations in source files 2009-01-12 20:56:34 +01:00
sun3 m68k: sun3 core - Kill warn_unused_result warnings 2009-01-12 20:56:38 +01:00
sun3x m68k: Kill several external declarations in source files 2009-01-12 20:56:34 +01:00
tools/amiga Convert files to UTF-8 and some cleanups 2007-10-19 23:21:04 +02:00
install.sh kbuild: use INSTALLKERNEL to select customized installkernel script 2009-09-20 12:18:14 +02:00
Kconfig m68k: convert to use arch_gettimeoffset() 2009-09-22 07:17:43 -07:00
Kconfig.debug Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
Makefile m68k: Add install target 2009-03-26 21:15:26 +01:00