Nikolay Aleksandrov
2015-Jul-23 16:07 UTC
[Bridge] [PATCH net] bridge: stp: when using userspace stp stop kernel hello and hold timers
From: Satish Ashok <sashok at cumulusnetworks.com>
Stop the kernel STP hello and hold timers when user-space STP is being
used to stop generating both packets. These should be handled only by
the respective STP which is in control. Also ensure that when the bridge
is up these timers are started only when running with kernel STP.
The kernel STP should function as before.
Test done using user-space RSTP.
Before patch:
14:55:35.043194 52:54:00:28:9d:4c > 01:80:c2:00:00:00, 802.3, length 52:
LLC, dsap STP (0x42) Individual, ssap STP (0x42) Command, ctrl 0x03: STP
802.1d, Config, Flags [none], bridge-id 8000.52:54:00:28:9d:4c.8001,
length 35
message-age 0.00s, max-age 20.00s, hello-time 2.00s,
forwarding-delay 15.00s
root-id 8000.52:54:00:28:9d:4c, root-pathcost 0
^^^^^^^
Kernel STP.
14:55:35.333807 52:54:00:28:9d:4c > 01:80:c2:00:00:00, 802.3, length 53:
LLC, dsap STP (0x42) Individual, ssap STP (0x42) Command, ctrl 0x03: STP
802.1w, Rapid STP, Flags [Learn, Forward], bridge-id
8000.52:54:00:28:9d:4c.8001, length 36
message-age 0.00s, max-age 20.00s, hello-time 3.00s,
forwarding-delay 15.00s
root-id 8000.52:54:00:28:9d:4c, root-pathcost 0, port-role
Designated
^^^^^^^
User-space STP (rstpd, configured with 3s hello-time)
After patch:
15:02:31.821511 52:54:00:28:9d:4c > 01:80:c2:00:00:00, 802.3, length 52:
LLC, dsap STP (0x42) Individual, ssap STP (0x42) Command, ctrl 0x03: STP
802.1d, Config, Flags [Topology change], bridge-id
8000.52:54:00:28:9d:4c.8002, length 35
message-age 0.00s, max-age 20.00s, hello-time 3.00s,
forwarding-delay 15.00s
root-id 8000.52:54:00:28:9d:4c, root-pathcost 0
15:02:34.821819 52:54:00:28:9d:4c > 01:80:c2:00:00:00, 802.3, length 52:
LLC, dsap STP (0x42) Individual, ssap STP (0x42) Command, ctrl 0x03: STP
802.1d, Config, Flags [Topology change], bridge-id
8000.52:54:00:28:9d:4c.8002, length 35
message-age 0.00s, max-age 20.00s, hello-time 3.00s,
forwarding-delay 15.00s
root-id 8000.52:54:00:28:9d:4c, root-pathcost 0
^^^^^
Only user-space STP.
Signed-off-by: Satish Ashok <sashok at cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
---
net/bridge/br_stp.c | 5 +++--
net/bridge/br_stp_if.c | 15 ++++++++++++++-
net/bridge/br_stp_timer.c | 4 +++-
3 files changed, 20 insertions(+), 4 deletions(-)
diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index b4b6dab9c285..ed74ffaa851f 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -209,8 +209,9 @@ void br_transmit_config(struct net_bridge_port *p)
br_send_config_bpdu(p, &bpdu);
p->topology_change_ack = 0;
p->config_pending = 0;
- mod_timer(&p->hold_timer,
- round_jiffies(jiffies + BR_HOLD_TIME));
+ if (p->br->stp_enabled == BR_KERNEL_STP)
+ mod_timer(&p->hold_timer,
+ round_jiffies(jiffies + BR_HOLD_TIME));
}
}
diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
index a2730e7196cd..962a149b117a 100644
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -48,7 +48,8 @@ void br_stp_enable_bridge(struct net_bridge *br)
struct net_bridge_port *p;
spin_lock_bh(&br->lock);
- mod_timer(&br->hello_timer, jiffies + br->hello_time);
+ if (br->stp_enabled == BR_KERNEL_STP)
+ mod_timer(&br->hello_timer, jiffies + br->hello_time);
mod_timer(&br->gc_timer, jiffies + HZ/10);
br_config_bpdu_generation(br);
@@ -127,6 +128,7 @@ static void br_stp_start(struct net_bridge *br)
int r;
char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
char *envp[] = { NULL };
+ struct net_bridge_port *p;
r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
@@ -140,6 +142,12 @@ static void br_stp_start(struct net_bridge *br)
if (r == 0) {
br->stp_enabled = BR_USER_STP;
br_debug(br, "userspace STP started\n");
+ /* Stop hello and hold timer */
+ spin_lock_bh(&br->lock);
+ del_timer(&br->hello_timer);
+ list_for_each_entry(p, &br->port_list, list)
+ del_timer(&p->hold_timer);
+ spin_unlock_bh(&br->lock);
} else {
br->stp_enabled = BR_KERNEL_STP;
br_debug(br, "using kernel STP\n");
@@ -156,12 +164,17 @@ static void br_stp_stop(struct net_bridge *br)
int r;
char *argv[] = { BR_STP_PROG, br->dev->name, "stop", NULL };
char *envp[] = { NULL };
+ struct net_bridge_port *p;
if (br->stp_enabled == BR_USER_STP) {
r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
br_info(br, "userspace STP stopped, return code %d\n", r);
/* To start timers on any ports left in blocking */
+ mod_timer(&br->hello_timer, jiffies + br->hello_time);
+ list_for_each_entry(p, &br->port_list, list)
+ mod_timer(&p->hold_timer,
+ round_jiffies(jiffies + BR_HOLD_TIME));
spin_lock_bh(&br->lock);
br_port_state_selection(br);
spin_unlock_bh(&br->lock);
diff --git a/net/bridge/br_stp_timer.c b/net/bridge/br_stp_timer.c
index 7caf7fae2d5b..5f0f5af0ec35 100644
--- a/net/bridge/br_stp_timer.c
+++ b/net/bridge/br_stp_timer.c
@@ -40,7 +40,9 @@ static void br_hello_timer_expired(unsigned long arg)
if (br->dev->flags & IFF_UP) {
br_config_bpdu_generation(br);
- mod_timer(&br->hello_timer, round_jiffies(jiffies +
br->hello_time));
+ if (br->stp_enabled != BR_USER_STP)
+ mod_timer(&br->hello_timer,
+ round_jiffies(jiffies + br->hello_time));
}
spin_unlock(&br->lock);
}
--
2.4.3
Stephen Hemminger
2015-Jul-23 16:59 UTC
[Bridge] [PATCH net] bridge: stp: when using userspace stp stop kernel hello and hold timers
On Thu, 23 Jul 2015 09:07:37 -0700 Nikolay Aleksandrov <nikolay at cumulusnetworks.com> wrote:> + /* Stop hello and hold timer */ > + spin_lock_bh(&br->lock); > + del_timer(&br->hello_timer); > + list_for_each_entry(p, &br->port_list, list) > + del_timer(&p->hold_timer); > + spin_unlock_bh(&br->lock);Wouldn't it be easier to use del_timer_sync here?
Nikolay Aleksandrov
2015-Jul-23 18:01 UTC
[Bridge] [PATCH net v2] bridge: stp: when using userspace stp stop kernel hello and hold timers
From: Nikolay Aleksandrov <razor at blackwall.org>
These should be handled only by the respective STP which is in control.
They become problematic for devices with limited resources with many
ports because the hold_timer is per port and fires each second and the
hello timer fires each 2 seconds even though it's global. While in
user-space STP mode these timers are completely unnecessary so it's better
to keep them off.
Also ensure that when the bridge is up these timers are started only when
running with kernel STP.
Signed-off-by: Satish Ashok <sashok at cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay at cumulusnetworks.com>
---
v2: fixed a locking issue and the commit message which was wrong
Stephen: I didn't use the del_timer_sync() because br->lock is acquired
in br_stp_start() and we shouldn't block.
net/bridge/br_stp.c | 5 +++--
net/bridge/br_stp_if.c | 13 ++++++++++++-
net/bridge/br_stp_timer.c | 4 +++-
3 files changed, 18 insertions(+), 4 deletions(-)
diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index b4b6dab9c285..ed74ffaa851f 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -209,8 +209,9 @@ void br_transmit_config(struct net_bridge_port *p)
br_send_config_bpdu(p, &bpdu);
p->topology_change_ack = 0;
p->config_pending = 0;
- mod_timer(&p->hold_timer,
- round_jiffies(jiffies + BR_HOLD_TIME));
+ if (p->br->stp_enabled == BR_KERNEL_STP)
+ mod_timer(&p->hold_timer,
+ round_jiffies(jiffies + BR_HOLD_TIME));
}
}
diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c
index a2730e7196cd..4ca449a16132 100644
--- a/net/bridge/br_stp_if.c
+++ b/net/bridge/br_stp_if.c
@@ -48,7 +48,8 @@ void br_stp_enable_bridge(struct net_bridge *br)
struct net_bridge_port *p;
spin_lock_bh(&br->lock);
- mod_timer(&br->hello_timer, jiffies + br->hello_time);
+ if (br->stp_enabled == BR_KERNEL_STP)
+ mod_timer(&br->hello_timer, jiffies + br->hello_time);
mod_timer(&br->gc_timer, jiffies + HZ/10);
br_config_bpdu_generation(br);
@@ -127,6 +128,7 @@ static void br_stp_start(struct net_bridge *br)
int r;
char *argv[] = { BR_STP_PROG, br->dev->name, "start", NULL };
char *envp[] = { NULL };
+ struct net_bridge_port *p;
r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
@@ -140,6 +142,10 @@ static void br_stp_start(struct net_bridge *br)
if (r == 0) {
br->stp_enabled = BR_USER_STP;
br_debug(br, "userspace STP started\n");
+ /* Stop hello and hold timers */
+ del_timer(&br->hello_timer);
+ list_for_each_entry(p, &br->port_list, list)
+ del_timer(&p->hold_timer);
} else {
br->stp_enabled = BR_KERNEL_STP;
br_debug(br, "using kernel STP\n");
@@ -156,12 +162,17 @@ static void br_stp_stop(struct net_bridge *br)
int r;
char *argv[] = { BR_STP_PROG, br->dev->name, "stop", NULL };
char *envp[] = { NULL };
+ struct net_bridge_port *p;
if (br->stp_enabled == BR_USER_STP) {
r = call_usermodehelper(BR_STP_PROG, argv, envp, UMH_WAIT_PROC);
br_info(br, "userspace STP stopped, return code %d\n", r);
/* To start timers on any ports left in blocking */
+ mod_timer(&br->hello_timer, jiffies + br->hello_time);
+ list_for_each_entry(p, &br->port_list, list)
+ mod_timer(&p->hold_timer,
+ round_jiffies(jiffies + BR_HOLD_TIME));
spin_lock_bh(&br->lock);
br_port_state_selection(br);
spin_unlock_bh(&br->lock);
diff --git a/net/bridge/br_stp_timer.c b/net/bridge/br_stp_timer.c
index 7caf7fae2d5b..5f0f5af0ec35 100644
--- a/net/bridge/br_stp_timer.c
+++ b/net/bridge/br_stp_timer.c
@@ -40,7 +40,9 @@ static void br_hello_timer_expired(unsigned long arg)
if (br->dev->flags & IFF_UP) {
br_config_bpdu_generation(br);
- mod_timer(&br->hello_timer, round_jiffies(jiffies +
br->hello_time));
+ if (br->stp_enabled != BR_USER_STP)
+ mod_timer(&br->hello_timer,
+ round_jiffies(jiffies + br->hello_time));
}
spin_unlock(&br->lock);
}
--
2.4.3