]> git.baikalelectronics.ru Git - kernel.git/commit
RDS: fix rds-ping spinlock recursion
authorjeff.liu <jeff.liu@oracle.com>
Mon, 8 Oct 2012 18:57:27 +0000 (18:57 +0000)
committerDavid S. Miller <davem@davemloft.net>
Tue, 9 Oct 2012 17:57:23 +0000 (13:57 -0400)
commit5ee660cb9767731a1258d19c1ff0fe8822eeed88
tree83a7113b1b7fd3f6d7b2222d66884da291afe328
parentaa29df3d7b5088c2657f360180d8c96e82c71dff
RDS: fix rds-ping spinlock recursion

This is the revised patch for fixing rds-ping spinlock recursion
according to Venkat's suggestions.

RDS ping/pong over TCP feature has been broken for years(2.6.39 to
3.6.0) since we have to set TCP cork and call kernel_sendmsg() between
ping/pong which both need to lock "struct sock *sk". However, this
lock has already been hold before rds_tcp_data_ready() callback is
triggerred. As a result, we always facing spinlock resursion which
would resulting in system panic.

Given that RDS ping is only used to test the connectivity and not for
serious performance measurements, we can queue the pong transmit to
rds_wq as a delayed response.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Venkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
CC: David S. Miller <davem@davemloft.net>
CC: James Morris <james.l.morris@oracle.com>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/rds/send.c