linux/net/tipc
Jon Maloy eb929a91b2 tipc: improve poll() for group member socket
The current criteria for returning POLLOUT from a group member socket is
too simplistic. It basically returns POLLOUT as soon as the group has
external destinations, something obviously leading to a lot of spinning
during destination congestion situations. At the same time, the internal
congestion handling is unnecessarily complex.

We now change this as follows.

- We introduce an 'open' flag in  struct tipc_group. This flag is used
  only to help poll() get the setting of POLLOUT right, and *not* for
  congeston handling as such. This means that a user can choose to
  ignore an  EAGAIN for a destination and go on sending messages to
  other destinations in the group if he wants to.

- The flag is set to false every time we return EAGAIN on a send call.

- The flag is set to true every time any member, i.e., not necessarily
  the member that caused EAGAIN, is removed from the small_win list.

- We remove the group member 'usr_pending' flag. The size of the send
  window and presence in the 'small_win' list is sufficient criteria
  for recognizing congestion.

This solution seems to be a reasonable compromise between 'anycast',
which is normally not waiting for POLLOUT for a specific destination,
and the other three send modes, which are.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-09 12:35:58 -05:00
..
addr.c tipc: simplify include dependencies 2015-05-14 12:24:45 -04:00
addr.h tipc: introduce constants for tipc address validation 2016-07-26 14:26:42 -07:00
bcast.c tipc: fall back to smaller MTU if allocation of local send skb fails 2017-12-01 15:21:25 -05:00
bcast.h tipc: make replicast a user selectable option 2017-01-20 12:10:17 -05:00
bearer.c tipc: error path leak fixes in tipc_enable_bearer() 2017-12-27 10:54:59 -05:00
bearer.h Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-09-01 17:42:05 -07:00
core.c netns: make struct pernet_operations::id unsigned int 2016-11-18 10:59:15 -05:00
core.h net: tipc: remove unused hardirq.h 2018-01-08 20:59:25 -05:00
discover.c net: tipc: Convert timers to use timer_setup() 2017-11-01 12:38:45 +09:00
discover.h tipc: eliminate buffer leak in bearer layer 2016-04-07 17:00:13 -04:00
eth_media.c tipc: make media address offset a common define 2015-02-27 18:18:48 -05:00
group.c tipc: improve poll() for group member socket 2018-01-09 12:35:58 -05:00
group.h tipc: improve poll() for group member socket 2018-01-09 12:35:58 -05:00
ib_media.c tipc: rename media/msg related definitions 2015-02-27 18:18:48 -05:00
Kconfig tipc: add ip/udp media type 2015-03-05 22:08:42 -05:00
link.c tipc: fall back to smaller MTU if allocation of local send skb fails 2017-12-01 15:21:25 -05:00
link.h tipc: transfer broadcast nacks in link state messages 2016-09-02 17:10:24 -07:00
Makefile Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-11-04 09:26:51 +09:00
monitor.c tipc: fix tipc_mon_delete() oops in tipc_enable_bearer() error path 2017-12-27 10:55:00 -05:00
monitor.h tipc: dump monitor attributes 2016-07-26 14:26:42 -07:00
msg.c tipc: fall back to smaller MTU if allocation of local send skb fails 2017-12-01 15:21:25 -05:00
msg.h tipc: fall back to smaller MTU if allocation of local send skb fails 2017-12-01 15:21:25 -05:00
name_distr.c tipc: allocate user memory with GFP_KERNEL flag 2017-01-16 13:31:53 -05:00
name_distr.h tipc: reduce code dependency between binding table and node layer 2015-11-20 14:06:10 -05:00
name_table.c tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
name_table.h tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
net.c netlink: pass extended ACK struct where available 2017-04-13 13:58:22 -04:00
net.h tipc: add peer removal functionality 2016-08-18 23:36:07 -07:00
netlink_compat.c net: tipc: constify genl_ops 2017-08-23 22:31:38 -07:00
netlink.c netlink: pass extended ACK struct to parsing functions 2017-04-13 13:58:22 -04:00
netlink.h tipc: make cluster size threshold for monitoring configurable 2016-07-26 14:26:42 -07:00
node.c tipc: enforce valid ratio between skb truesize and contents 2017-11-16 10:49:00 +09:00
node.h tipc: introduce communication groups 2017-10-13 08:46:00 -07:00
server.c tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
server.h tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
socket.c tipc: improve poll() for group member socket 2018-01-09 12:35:58 -05:00
socket.h tipc: redesign connection-level flow control 2016-05-03 15:51:16 -04:00
subscr.c tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
subscr.h tipc: improve groupcast scope handling 2018-01-09 12:35:58 -05:00
sysctl.c tipc: add name distributor resiliency queue 2014-09-01 17:51:48 -07:00
udp_media.c tipc: call tipc_rcv() only if bearer is up in tipc_udp_recv() 2017-12-01 15:14:22 -05:00
udp_media.h tipc: add UDP remoteip dump to netlink API 2016-08-26 21:38:41 -07:00