diff options
| author | Nils Carlson <nils.carlson@ericsson.com> | 2011-03-03 22:09:11 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2011-03-07 16:02:17 -0800 |
| commit | 16d79d7dc98e56d4700054b9b785a92102d8998c (patch) | |
| tree | 975e808eed2b39d12fd09bb884fc24dd013410d6 /drivers/net/bonding/bond_3ad.c | |
| parent | ce3c869283739379134e1a90c37dd1a30b5f31b7 (diff) | |
| download | linux-16d79d7dc98e56d4700054b9b785a92102d8998c.tar.bz2 | |
bonding 802.3ad: Fix the state machine locking v2
Changes since v1:
* Clarify an unclear comment
* Move a (possible) name change to a separate patch
The ad_rx_machine, ad_periodic_machine and ad_port_selection_logic
functions all inspect and alter common fields within the port structure.
Previous to this patch, only the ad_rx_machines were mutexed, and the
periodic and port_selection could run unmutexed against an ad_rx_machine
trigged by an arriving LACPDU.
This patch remedies the situation by protecting all the state machines
from concurrency. This is accomplished by locking around all the state
machines for a given port, which are executed at regular intervals; and
the ad_rx_machine when handling an incoming LACPDU.
Signed-off-by: Nils Carlson <nils.carlson@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/bonding/bond_3ad.c')
| -rw-r--r-- | drivers/net/bonding/bond_3ad.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index 1024ae158227..de30c8d6301e 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -1025,9 +1025,6 @@ static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port) { rx_states_t last_state; - // Lock to prevent 2 instances of this function to run simultaneously(rx interrupt and periodic machine callback) - __get_rx_machine_lock(port); - // keep current State Machine state to compare later if it was changed last_state = port->sm_rx_state; @@ -1133,7 +1130,6 @@ static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port) pr_err("%s: An illegal loopback occurred on adapter (%s).\n" "Check the configuration to verify that all adapters are connected to 802.3ad compliant switch ports\n", port->slave->dev->master->name, port->slave->dev->name); - __release_rx_machine_lock(port); return; } __update_selected(lacpdu, port); @@ -1153,7 +1149,6 @@ static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port) break; } } - __release_rx_machine_lock(port); } /** @@ -2155,6 +2150,12 @@ void bond_3ad_state_machine_handler(struct work_struct *work) goto re_arm; } + /* Lock around state machines to protect data accessed + * by all (e.g., port->sm_vars). ad_rx_machine may run + * concurrently due to incoming LACPDU. + */ + __get_rx_machine_lock(port); + ad_rx_machine(NULL, port); ad_periodic_machine(port); ad_port_selection_logic(port); @@ -2164,6 +2165,8 @@ void bond_3ad_state_machine_handler(struct work_struct *work) // turn off the BEGIN bit, since we already handled it if (port->sm_vars & AD_PORT_BEGIN) port->sm_vars &= ~AD_PORT_BEGIN; + + __release_rx_machine_lock(port); } re_arm: @@ -2200,7 +2203,10 @@ static void bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave, u case AD_TYPE_LACPDU: pr_debug("Received LACPDU on port %d\n", port->actor_port_number); + /* Protect against concurrent state machines */ + __get_rx_machine_lock(port); ad_rx_machine(lacpdu, port); + __release_rx_machine_lock(port); break; case AD_TYPE_MARKER: |