kernel/linux.git/net/rds/cong.c, branch v6.6.131

net: rds: delete duplicated words

2020-09-18T21:12:43+00:00

Drop repeated words in net/rds/. Signed-off-by: Randy Dunlap Cc: "David S. Miller" Cc: Jakub Kicinski Cc: Santosh Shilimkar Cc: linux-rdma@vger.kernel.org Cc: rds-devel@oss.oracle.com Signed-off-by: David S. Miller

rds: Changing IP address internal representation to struct in6_addr

2018-07-24T04:17:44+00:00

This patch changes the internal representation of an IP address to use struct in6_addr. IPv4 address is stored as an IPv4 mapped address. All the functions which take an IP address as argument are also changed to use struct in6_addr. But RDS socket layer is not modified such that it still does not accept IPv6 address from an application. And RDS layer does not accept nor initiate IPv6 connections. v2: Fixed sparse warnings. Signed-off-by: Ka-Cheong Poon Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller

rds: tcp: use rds_destroy_pending() to synchronize netns/module teardown and rds connection/workq management

2018-02-08T20:23:52+00:00

An rds_connection can get added during netns deletion between lines 528 and 529 of 506 static void rds_tcp_kill_sock(struct net *net) : /* code to pull out all the rds_connections that should be destroyed */ : 528 spin_unlock_irq(&rds_tcp_conn_lock); 529 list_for_each_entry_safe(tc, _tc, &tmp_list, t_tcp_node) 530 rds_conn_destroy(tc->t_cpath->cp_conn); Such an rds_connection would miss out the rds_conn_destroy() loop (that cancels all pending work) and (if it was scheduled after netns deletion) could trigger the use-after-free. A similar race-window exists for the module unload path in rds_tcp_exit -> rds_tcp_destroy_conns Concurrency with netns deletion (rds_tcp_kill_sock()) must be handled by checking check_net() before enqueuing new work or adding new connections. Concurrency with module-unload is handled by maintaining a module specific flag that is set at the start of the module exit function, and must be checked before enqueuing new work or adding new connections. This commit refactors existing RDS_DESTROY_PENDING checks added by commit 3db6e0d172c9 ("rds: use RCU to synchronize work-enqueue with connection teardown") and consolidates all the concurrency checks listed above into the function rds_destroy_pending(). Signed-off-by: Sowmini Varadhan Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller

rds: use RCU to synchronize work-enqueue with connection teardown

2018-01-05T18:39:18+00:00

rds_sendmsg() can enqueue work on cp_send_w from process context, but it should not enqueue this work if connection teardown has commenced (else we risk enquing work after rds_conn_path_destroy() has assumed that all work has been cancelled/flushed). Similarly some other functions like rds_cong_queue_updates and rds_tcp_data_ready are called in softirq context, and may end up enqueuing work on rds_wq after rds_conn_path_destroy() has assumed that all workqs are quiesced. Check the RDS_DESTROY_PENDING bit and use rcu synchronization to avoid all these races. Signed-off-by: Sowmini Varadhan Acked-by: Santosh Shilimkar Signed-off-by: David S. Miller

RDS: split out connection specific state from rds_connection to rds_conn_path

2016-06-15T06:50:41+00:00

In preparation for multipath RDS, split the rds_connection structure into a base structure, and a per-path struct rds_conn_path. The base structure tracks information and locks common to all paths. The workqs for send/recv/shutdown etc are tracked per rds_conn_path. Thus the workq callbacks now work with rds_conn_path. This commit allows for one rds_conn_path per rds_connection, and will be extended into multiple conn_paths in subsequent commits. Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller

RDS: Fix the atomicity for congestion map update

2016-04-16T23:01:05+00:00

Two different threads with different rds sockets may be in rds_recv_rcvbuf_delta() via receive path. If their ports both map to the same word in the congestion map, then using non-atomic ops to update it could cause the map to be incorrect. Lets use atomics to avoid such an issue. Full credit to Wengang for finding the issue, analysing it and also pointing out to offending code with spin lock based fix. Reviewed-by: Leon Romanovsky Signed-off-by: Wengang Wang Signed-off-by: Santosh Shilimkar Signed-off-by: David S. Miller

rds: rds_cong_queue_updates needs to defer the congestion update transmission

2015-02-11T22:35:44+00:00

When the RDS transport is TCP, we cannot inline the call to rds_send_xmit from rds_cong_queue_update because (a) we are already holding the sock_lock in the recv path, and will deadlock when tcp_setsockopt/tcp_sendmsg try to get the sock lock (b) cong_queue_update does an irqsave on the rds_cong_lock, and this will trigger warnings (for a good reason) from functions called out of sock_lock. This patch reverts the change introduced by 2fa57129d ("RDS: Bypass workqueue when queueing cong updates"). The patch has been verified for both RDS/TCP as well as RDS/RDMA to ensure that there are not regressions for either transport: - for verification of RDS/TCP a client-server unit-test was used, with the server blocked in gdb and thus unable to drain its rcvbuf, eventually triggering a RDS congestion update. - for RDS/RDMA, the standard IB regression tests were used Signed-off-by: Sowmini Varadhan Signed-off-by: David S. Miller

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

2011-10-31T23:30:30+00:00

These files are non modular, but need to export symbols using the macros now living in export.h -- call out the include so that things won't break when we remove the implicit presence of module.h from everywhere. Signed-off-by: Paul Gortmaker

rds: use little-endian bitops

2011-03-24T02:46:16+00:00

As a preparation for removing ext2 non-atomic bit operations from asm/bitops.h. This converts ext2 non-atomic bit operations to little-endian bit operations. Signed-off-by: Akinobu Mita Cc: Andy Grover Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

rds: stop including asm-generic/bitops/le.h directly

2011-03-24T02:46:10+00:00

asm-generic/bitops/le.h is only intended to be included directly from asm-generic/bitops/ext2-non-atomic.h or asm-generic/bitops/minix-le.h which implements generic ext2 or minix bit operations. This stops including asm-generic/bitops/le.h directly and use ext2 non-atomic bit operations instead. It seems odd to use ext2_*_bit() on rds, but it will replaced with __{set,clear,test}_bit_le() after introducing little endian bit operations for all architectures. This indirect step is necessary to maintain bisectability for some architectures which have their own little-endian bit operations. Signed-off-by: Akinobu Mita Cc: Andy Grover Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds