From d6dfd1310d3562698fd7c3c086f6c239f96394ac Mon Sep 17 00:00:00 2001 From: Corey Minyard Date: Fri, 31 Mar 2006 02:30:41 -0800 Subject: [PATCH] [PATCH] IPMI: convert from semaphores to mutexes Convert the remaining semaphores to mutexes in the IPMI driver. The watchdog was using a semaphore as a real semaphore (for IPC), so the conversion there required adding a completion. Signed-off-by: Corey Minyard Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/char/ipmi/ipmi_devintf.c | 18 +++++----- drivers/char/ipmi/ipmi_msghandler.c | 23 +++++++------ drivers/char/ipmi/ipmi_si_intf.c | 24 ++++++------- drivers/char/ipmi/ipmi_watchdog.c | 53 ++++++++++++++++------------- 4 files changed, 63 insertions(+), 55 deletions(-) diff --git a/drivers/char/ipmi/ipmi_devintf.c b/drivers/char/ipmi/ipmi_devintf.c index 932feedda262..e1c95374984c 100644 --- a/drivers/char/ipmi/ipmi_devintf.c +++ b/drivers/char/ipmi/ipmi_devintf.c @@ -42,7 +42,7 @@ #include #include #include -#include +#include #include #include #include @@ -55,7 +55,7 @@ struct ipmi_file_private struct file *file; struct fasync_struct *fasync_queue; wait_queue_head_t wait; - struct semaphore recv_sem; + struct mutex recv_mutex; int default_retries; unsigned int default_retry_time_ms; }; @@ -141,7 +141,7 @@ static int ipmi_open(struct inode *inode, struct file *file) INIT_LIST_HEAD(&(priv->recv_msgs)); init_waitqueue_head(&priv->wait); priv->fasync_queue = NULL; - sema_init(&(priv->recv_sem), 1); + mutex_init(&priv->recv_mutex); /* Use the low-level defaults. */ priv->default_retries = -1; @@ -285,15 +285,15 @@ static int ipmi_ioctl(struct inode *inode, break; } - /* We claim a semaphore because we don't want two + /* We claim a mutex because we don't want two users getting something from the queue at a time. Since we have to release the spinlock before we can copy the data to the user, it's possible another user will grab something from the queue, too. Then the messages might get out of order if something fails and the message gets put back onto the - queue. This semaphore prevents that problem. */ - down(&(priv->recv_sem)); + queue. This mutex prevents that problem. */ + mutex_lock(&priv->recv_mutex); /* Grab the message off the list. */ spin_lock_irqsave(&(priv->recv_msg_lock), flags); @@ -352,7 +352,7 @@ static int ipmi_ioctl(struct inode *inode, goto recv_putback_on_err; } - up(&(priv->recv_sem)); + mutex_unlock(&priv->recv_mutex); ipmi_free_recv_msg(msg); break; @@ -362,11 +362,11 @@ static int ipmi_ioctl(struct inode *inode, spin_lock_irqsave(&(priv->recv_msg_lock), flags); list_add(entry, &(priv->recv_msgs)); spin_unlock_irqrestore(&(priv->recv_msg_lock), flags); - up(&(priv->recv_sem)); + mutex_unlock(&priv->recv_mutex); break; recv_err: - up(&(priv->recv_sem)); + mutex_unlock(&priv->recv_mutex); break; } diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c index c0c862cce1c3..0ded046d5aa8 100644 --- a/drivers/char/ipmi/ipmi_msghandler.c +++ b/drivers/char/ipmi/ipmi_msghandler.c @@ -38,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -234,7 +235,7 @@ struct ipmi_smi /* The list of command receivers that are registered for commands on this interface. */ - struct semaphore cmd_rcvrs_lock; + struct mutex cmd_rcvrs_mutex; struct list_head cmd_rcvrs; /* Events that were queues because no one was there to receive @@ -387,10 +388,10 @@ static void clean_up_interface_data(ipmi_smi_t intf) /* Wholesale remove all the entries from the list in the * interface and wait for RCU to know that none are in use. */ - down(&intf->cmd_rcvrs_lock); + mutex_lock(&intf->cmd_rcvrs_mutex); list_add_rcu(&list, &intf->cmd_rcvrs); list_del_rcu(&intf->cmd_rcvrs); - up(&intf->cmd_rcvrs_lock); + mutex_unlock(&intf->cmd_rcvrs_mutex); synchronize_rcu(); list_for_each_entry_safe(rcvr, rcvr2, &list, link) @@ -846,7 +847,7 @@ int ipmi_destroy_user(ipmi_user_t user) * since other things may be using it till we do * synchronize_rcu()) then free everything in that list. */ - down(&intf->cmd_rcvrs_lock); + mutex_lock(&intf->cmd_rcvrs_mutex); list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link) { if (rcvr->user == user) { list_del_rcu(&rcvr->link); @@ -854,7 +855,7 @@ int ipmi_destroy_user(ipmi_user_t user) rcvrs = rcvr; } } - up(&intf->cmd_rcvrs_lock); + mutex_unlock(&intf->cmd_rcvrs_mutex); synchronize_rcu(); while (rcvrs) { rcvr = rcvrs; @@ -984,7 +985,7 @@ int ipmi_register_for_cmd(ipmi_user_t user, rcvr->netfn = netfn; rcvr->user = user; - down(&intf->cmd_rcvrs_lock); + mutex_lock(&intf->cmd_rcvrs_mutex); /* Make sure the command/netfn is not already registered. */ entry = find_cmd_rcvr(intf, netfn, cmd); if (entry) { @@ -995,7 +996,7 @@ int ipmi_register_for_cmd(ipmi_user_t user, list_add_rcu(&rcvr->link, &intf->cmd_rcvrs); out_unlock: - up(&intf->cmd_rcvrs_lock); + mutex_unlock(&intf->cmd_rcvrs_mutex); if (rv) kfree(rcvr); @@ -1009,17 +1010,17 @@ int ipmi_unregister_for_cmd(ipmi_user_t user, ipmi_smi_t intf = user->intf; struct cmd_rcvr *rcvr; - down(&intf->cmd_rcvrs_lock); + mutex_lock(&intf->cmd_rcvrs_mutex); /* Make sure the command/netfn is not already registered. */ rcvr = find_cmd_rcvr(intf, netfn, cmd); if ((rcvr) && (rcvr->user == user)) { list_del_rcu(&rcvr->link); - up(&intf->cmd_rcvrs_lock); + mutex_unlock(&intf->cmd_rcvrs_mutex); synchronize_rcu(); kfree(rcvr); return 0; } else { - up(&intf->cmd_rcvrs_lock); + mutex_unlock(&intf->cmd_rcvrs_mutex); return -ENOENT; } } @@ -2365,7 +2366,7 @@ int ipmi_register_smi(struct ipmi_smi_handlers *handlers, spin_lock_init(&intf->events_lock); INIT_LIST_HEAD(&intf->waiting_events); intf->waiting_events_count = 0; - init_MUTEX(&intf->cmd_rcvrs_lock); + mutex_init(&intf->cmd_rcvrs_mutex); INIT_LIST_HEAD(&intf->cmd_rcvrs); init_waitqueue_head(&intf->waitq); diff --git a/drivers/char/ipmi/ipmi_si_intf.c b/drivers/char/ipmi/ipmi_si_intf.c index 2da5845a383a..a86c0f29953e 100644 --- a/drivers/char/ipmi/ipmi_si_intf.c +++ b/drivers/char/ipmi/ipmi_si_intf.c @@ -1014,7 +1014,7 @@ static struct ipmi_smi_handlers handlers = #define SI_MAX_PARMS 4 static LIST_HEAD(smi_infos); -static DECLARE_MUTEX(smi_infos_lock); +static DEFINE_MUTEX(smi_infos_lock); static int smi_num; /* Used to sequence the SMIs */ #define DEFAULT_REGSPACING 1 @@ -2276,7 +2276,7 @@ static int try_smi_init(struct smi_info *new_smi) new_smi->slave_addr, new_smi->irq); } - down(&smi_infos_lock); + mutex_lock(&smi_infos_lock); if (!is_new_interface(new_smi)) { printk(KERN_WARNING "ipmi_si: duplicate interface\n"); rv = -EBUSY; @@ -2432,7 +2432,7 @@ static int try_smi_init(struct smi_info *new_smi) list_add_tail(&new_smi->link, &smi_infos); - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); printk(" IPMI %s interface initialized\n",si_to_str[new_smi->si_type]); @@ -2469,7 +2469,7 @@ static int try_smi_init(struct smi_info *new_smi) kfree(new_smi); - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); return rv; } @@ -2527,26 +2527,26 @@ static __devinit int init_ipmi_si(void) #endif if (si_trydefaults) { - down(&smi_infos_lock); + mutex_lock(&smi_infos_lock); if (list_empty(&smi_infos)) { /* No BMC was found, try defaults. */ - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); default_find_bmc(); } else { - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); } } - down(&smi_infos_lock); + mutex_lock(&smi_infos_lock); if (list_empty(&smi_infos)) { - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); #ifdef CONFIG_PCI pci_unregister_driver(&ipmi_pci_driver); #endif printk("ipmi_si: Unable to find any System Interface(s)\n"); return -ENODEV; } else { - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); return 0; } } @@ -2622,10 +2622,10 @@ static __exit void cleanup_ipmi_si(void) pci_unregister_driver(&ipmi_pci_driver); #endif - down(&smi_infos_lock); + mutex_lock(&smi_infos_lock); list_for_each_entry_safe(e, tmp_e, &smi_infos, link) cleanup_one_si(e); - up(&smi_infos_lock); + mutex_unlock(&smi_infos_lock); driver_unregister(&ipmi_driver); } diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c index 2872c9575528..2d11ddd99e55 100644 --- a/drivers/char/ipmi/ipmi_watchdog.c +++ b/drivers/char/ipmi/ipmi_watchdog.c @@ -39,6 +39,7 @@ #include #include #include +#include #include #include #include @@ -303,21 +304,22 @@ static int ipmi_heartbeat(void); static void panic_halt_ipmi_heartbeat(void); -/* We use a semaphore to make sure that only one thing can send a set +/* We use a mutex to make sure that only one thing can send a set timeout at one time, because we only have one copy of the data. - The semaphore is claimed when the set_timeout is sent and freed + The mutex is claimed when the set_timeout is sent and freed when both messages are free. */ static atomic_t set_timeout_tofree = ATOMIC_INIT(0); -static DECLARE_MUTEX(set_timeout_lock); +static DEFINE_MUTEX(set_timeout_lock); +static DECLARE_COMPLETION(set_timeout_wait); static void set_timeout_free_smi(struct ipmi_smi_msg *msg) { if (atomic_dec_and_test(&set_timeout_tofree)) - up(&set_timeout_lock); + complete(&set_timeout_wait); } static void set_timeout_free_recv(struct ipmi_recv_msg *msg) { if (atomic_dec_and_test(&set_timeout_tofree)) - up(&set_timeout_lock); + complete(&set_timeout_wait); } static struct ipmi_smi_msg set_timeout_smi_msg = { @@ -399,7 +401,7 @@ static int ipmi_set_timeout(int do_heartbeat) /* We can only send one of these at a time. */ - down(&set_timeout_lock); + mutex_lock(&set_timeout_lock); atomic_set(&set_timeout_tofree, 2); @@ -407,16 +409,21 @@ static int ipmi_set_timeout(int do_heartbeat) &set_timeout_recv_msg, &send_heartbeat_now); if (rv) { - up(&set_timeout_lock); - } else { - if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB) - || ((send_heartbeat_now) - && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY))) - { - rv = ipmi_heartbeat(); - } + mutex_unlock(&set_timeout_lock); + goto out; + } + + wait_for_completion(&set_timeout_wait); + + if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB) + || ((send_heartbeat_now) + && (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY))) + { + rv = ipmi_heartbeat(); } + mutex_unlock(&set_timeout_lock); +out: return rv; } @@ -458,17 +465,17 @@ static void panic_halt_ipmi_set_timeout(void) The semaphore is claimed when the set_timeout is sent and freed when both messages are free. */ static atomic_t heartbeat_tofree = ATOMIC_INIT(0); -static DECLARE_MUTEX(heartbeat_lock); -static DECLARE_MUTEX_LOCKED(heartbeat_wait_lock); +static DEFINE_MUTEX(heartbeat_lock); +static DECLARE_COMPLETION(heartbeat_wait); static void heartbeat_free_smi(struct ipmi_smi_msg *msg) { if (atomic_dec_and_test(&heartbeat_tofree)) - up(&heartbeat_wait_lock); + complete(&heartbeat_wait); } static void heartbeat_free_recv(struct ipmi_recv_msg *msg) { if (atomic_dec_and_test(&heartbeat_tofree)) - up(&heartbeat_wait_lock); + complete(&heartbeat_wait); } static struct ipmi_smi_msg heartbeat_smi_msg = { @@ -511,14 +518,14 @@ static int ipmi_heartbeat(void) return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY); } - down(&heartbeat_lock); + mutex_lock(&heartbeat_lock); atomic_set(&heartbeat_tofree, 2); /* Don't reset the timer if we have the timer turned off, that re-enables the watchdog. */ if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE) { - up(&heartbeat_lock); + mutex_unlock(&heartbeat_lock); return 0; } @@ -539,14 +546,14 @@ static int ipmi_heartbeat(void) &heartbeat_recv_msg, 1); if (rv) { - up(&heartbeat_lock); + mutex_unlock(&heartbeat_lock); printk(KERN_WARNING PFX "heartbeat failure: %d\n", rv); return rv; } /* Wait for the heartbeat to be sent. */ - down(&heartbeat_wait_lock); + wait_for_completion(&heartbeat_wait); if (heartbeat_recv_msg.msg.data[0] != 0) { /* Got an error in the heartbeat response. It was already @@ -555,7 +562,7 @@ static int ipmi_heartbeat(void) rv = -EINVAL; } - up(&heartbeat_lock); + mutex_unlock(&heartbeat_lock); return rv; } -- 2.20.1