Commit 449f4544267e73d5db372971da63634707c32299
Committed by
David S. Miller
David S. Miller
1 parent
034cfe48d0
Exists in
master
and in
4 other branches
macvlan: remove one synchronize_rcu() call
When one macvlan device is dismantled, we can avoid one synchronize_rcu() call done after deletion from hash list, since caller will perform a synchronize_net() call after its ndo_stop() call. Add a new netdev->dismantle field to signal this dismantle intent. Reduces RTNL hold time. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Patrick McHardy <kaber@trash.net> CC: Ben Greear <greearb@candelatech.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Showing 3 changed files with 9 additions and 6 deletions Side-by-side Diff
drivers/net/macvlan.c
| ... | ... | @@ -70,16 +70,17 @@ |
| 70 | 70 | hlist_add_head_rcu(&vlan->hlist, &port->vlan_hash[addr[5]]); |
| 71 | 71 | } |
| 72 | 72 | |
| 73 | -static void macvlan_hash_del(struct macvlan_dev *vlan) | |
| 73 | +static void macvlan_hash_del(struct macvlan_dev *vlan, bool sync) | |
| 74 | 74 | { |
| 75 | 75 | hlist_del_rcu(&vlan->hlist); |
| 76 | - synchronize_rcu(); | |
| 76 | + if (sync) | |
| 77 | + synchronize_rcu(); | |
| 77 | 78 | } |
| 78 | 79 | |
| 79 | 80 | static void macvlan_hash_change_addr(struct macvlan_dev *vlan, |
| 80 | 81 | const unsigned char *addr) |
| 81 | 82 | { |
| 82 | - macvlan_hash_del(vlan); | |
| 83 | + macvlan_hash_del(vlan, true); | |
| 83 | 84 | /* Now that we are unhashed it is safe to change the device |
| 84 | 85 | * address without confusing packet delivery. |
| 85 | 86 | */ |
| ... | ... | @@ -345,7 +346,7 @@ |
| 345 | 346 | dev_uc_del(lowerdev, dev->dev_addr); |
| 346 | 347 | |
| 347 | 348 | hash_del: |
| 348 | - macvlan_hash_del(vlan); | |
| 349 | + macvlan_hash_del(vlan, !dev->dismantle); | |
| 349 | 350 | return 0; |
| 350 | 351 | } |
| 351 | 352 |
include/linux/netdevice.h
| ... | ... | @@ -1293,7 +1293,9 @@ |
| 1293 | 1293 | NETREG_UNREGISTERED, /* completed unregister todo */ |
| 1294 | 1294 | NETREG_RELEASED, /* called free_netdev */ |
| 1295 | 1295 | NETREG_DUMMY, /* dummy device for NAPI poll */ |
| 1296 | - } reg_state:16; | |
| 1296 | + } reg_state:8; | |
| 1297 | + | |
| 1298 | + bool dismantle; /* device is going do be freed */ | |
| 1297 | 1299 | |
| 1298 | 1300 | enum { |
| 1299 | 1301 | RTNL_LINK_INITIALIZED, |