From 7e0838404541d2758bee089632690aabd82f3d5d Mon Sep 17 00:00:00 2001 From: Stephen Hemminger Date: Fri, 12 Jun 2009 19:02:46 +0000 Subject: [PATCH] bonding: remove bonding read/write semaphore The whole read/write semaphore locking can be removed. It doesn't add any protection that isn't already done by using the RTNL mutex properly. Signed-off-by: Stephen Hemminger Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 16 +++------------- drivers/net/bonding/bond_sysfs.c | 23 +++-------------------- drivers/net/bonding/bonding.h | 3 --- 3 files changed, 6 insertions(+), 36 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 99ddd283e15e..23b832ffe7a9 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -3489,10 +3489,10 @@ static int bond_event_changename(struct bonding *bond) { bond_remove_proc_entry(bond); bond_create_proc_entry(bond); - down_write(&(bonding_rwsem)); + bond_destroy_sysfs_entry(bond); bond_create_sysfs_entry(bond); - up_write(&(bonding_rwsem)); + return NOTIFY_DONE; } @@ -4015,7 +4015,6 @@ static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd return -EPERM; } - down_write(&(bonding_rwsem)); slave_dev = dev_get_by_name(&init_net, ifr->ifr_slave); pr_debug("slave_dev=%p: \n", slave_dev); @@ -4048,7 +4047,6 @@ static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd dev_put(slave_dev); } - up_write(&(bonding_rwsem)); return res; } @@ -5123,8 +5121,6 @@ int bond_create(const char *name) int res; rtnl_lock(); - down_write(&bonding_rwsem); - /* Check to see if the bond already exists. */ if (name) { list_for_each_entry(bond, &bond_dev_list, bond_list) @@ -5173,24 +5169,20 @@ int bond_create(const char *name) goto out_bond; } - up_write(&bonding_rwsem); - rtnl_unlock(); /* allows sysfs registration of net device */ res = bond_create_sysfs_entry(netdev_priv(bond_dev)); if (res < 0) goto out_unreg; + rtnl_unlock(); return 0; out_unreg: - rtnl_lock(); - down_write(&bonding_rwsem); unregister_netdevice(bond_dev); out_bond: bond_deinit(bond_dev); out_netdev: free_netdev(bond_dev); out_rtnl: - up_write(&bonding_rwsem); rtnl_unlock(); return res; } @@ -5209,8 +5201,6 @@ static int __init bonding_init(void) bond_create_proc_dir(); - init_rwsem(&bonding_rwsem); - for (i = 0; i < max_bonds; i++) { res = bond_create(NULL); if (res) diff --git a/drivers/net/bonding/bond_sysfs.c b/drivers/net/bonding/bond_sysfs.c index 1172fe649352..8041b6793532 100644 --- a/drivers/net/bonding/bond_sysfs.c +++ b/drivers/net/bonding/bond_sysfs.c @@ -44,20 +44,6 @@ /*---------------------------- Declarations -------------------------------*/ static int expected_refcount = -1; -/*--------------------------- Data Structures -----------------------------*/ - -/* Bonding sysfs lock. Why can't we just use the subsystem lock? - * Because kobject_register tries to acquire the subsystem lock. If - * we already hold the lock (which we would if the user was creating - * a new bond through the sysfs interface), we deadlock. - * This lock is only needed when deleting a bond - we need to make sure - * that we don't collide with an ongoing ioctl. - */ - -struct rw_semaphore bonding_rwsem; - - - /*------------------------------ Functions --------------------------------*/ @@ -70,7 +56,7 @@ static ssize_t bonding_show_bonds(struct class *cls, char *buf) int res = 0; struct bonding *bond; - down_read(&(bonding_rwsem)); + rtnl_lock(); list_for_each_entry(bond, &bond_dev_list, bond_list) { if (res > (PAGE_SIZE - IFNAMSIZ)) { @@ -84,7 +70,8 @@ static ssize_t bonding_show_bonds(struct class *cls, char *buf) } if (res) buf[res-1] = '\n'; /* eat the leftover space */ - up_read(&(bonding_rwsem)); + + rtnl_unlock(); return res; } @@ -122,7 +109,6 @@ static ssize_t bonding_store_bonds(struct class *cls, const char *buffer, size_t if (command[0] == '-') { rtnl_lock(); - down_write(&bonding_rwsem); list_for_each_entry(bond, &bond_dev_list, bond_list) if (strnicmp(bond->dev->name, ifname, IFNAMSIZ) == 0) { @@ -157,7 +143,6 @@ err_no_cmd: return -EPERM; out_unlock: - up_write(&bonding_rwsem); rtnl_unlock(); /* Always return either count or an error. If you return 0, you'll @@ -253,7 +238,6 @@ static ssize_t bonding_store_slaves(struct device *d, if (!rtnl_trylock()) return restart_syscall(); - down_write(&(bonding_rwsem)); sscanf(buffer, "%16s", command); /* IFNAMSIZ*/ ifname = command + 1; @@ -357,7 +341,6 @@ err_no_cmd: ret = -EPERM; out: - up_write(&(bonding_rwsem)); rtnl_unlock(); return ret; } diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h index a6efa0963717..af81e9b7fe34 100644 --- a/drivers/net/bonding/bonding.h +++ b/drivers/net/bonding/bonding.h @@ -351,9 +351,6 @@ extern const struct bond_parm_tbl arp_validate_tbl[]; extern const struct bond_parm_tbl fail_over_mac_tbl[]; extern struct bond_parm_tbl ad_select_tbl[]; -/* exported from bond_sysfs.c */ -extern struct rw_semaphore bonding_rwsem; - #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) void bond_send_unsolicited_na(struct bonding *bond); void bond_register_ipv6_notifier(void); -- 2.11.0