| Message ID | 20181210214955.1826522-1-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 2a727f6091372231281efaa8a5f56ee79509fd83 |
| Headers | show |
| Series | pci: ibmphp_hpc: turn semaphores into completions or mutexes | expand |
On Mon, Dec 10, 2018 at 10:49:10PM +0100, Arnd Bergmann wrote: > The sem_exit variable is conceptually a completion, so it should > be called that. > > Similarly, the semOperations semaphore is a simple mutex, and > can be changed into that, respectively. > > With both converted, the ibmphp_hpc_initvars() function is no longer > used and can be removed. > > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Applied to pci/hotplug for v5.1, thanks! > --- > drivers/pci/hotplug/ibmphp.h | 1 - > drivers/pci/hotplug/ibmphp_core.c | 2 -- > drivers/pci/hotplug/ibmphp_hpc.c | 47 +++++++++---------------------- > 3 files changed, 14 insertions(+), 36 deletions(-) > > diff --git a/drivers/pci/hotplug/ibmphp.h b/drivers/pci/hotplug/ibmphp.h > index b89f850c3a4e..e90a4ebf6550 100644 > --- a/drivers/pci/hotplug/ibmphp.h > +++ b/drivers/pci/hotplug/ibmphp.h > @@ -378,7 +378,6 @@ int ibmphp_add_pfmem_from_mem(struct resource_node *); > struct bus_node *ibmphp_find_res_bus(u8); > void ibmphp_print_test(void); /* for debugging purposes */ > > -void ibmphp_hpc_initvars(void); > int ibmphp_hpc_readslot(struct slot *, u8, u8 *); > int ibmphp_hpc_writeslot(struct slot *, u8); > void ibmphp_lock_operations(void); > diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c > index 5752b57198e3..e04b17d81e38 100644 > --- a/drivers/pci/hotplug/ibmphp_core.c > +++ b/drivers/pci/hotplug/ibmphp_core.c > @@ -1312,8 +1312,6 @@ static int __init ibmphp_init(void) > > ibmphp_debug = debug; > > - ibmphp_hpc_initvars(); > - > for (i = 0; i < 16; i++) > irqs[i] = 0; > > diff --git a/drivers/pci/hotplug/ibmphp_hpc.c b/drivers/pci/hotplug/ibmphp_hpc.c > index 752c384cbd4c..508a62a6b5f9 100644 > --- a/drivers/pci/hotplug/ibmphp_hpc.c > +++ b/drivers/pci/hotplug/ibmphp_hpc.c > @@ -15,13 +15,13 @@ > > #include <linux/wait.h> > #include <linux/time.h> > +#include <linux/completion.h> > #include <linux/delay.h> > #include <linux/module.h> > #include <linux/pci.h> > #include <linux/init.h> > #include <linux/mutex.h> > #include <linux/sched.h> > -#include <linux/semaphore.h> > #include <linux/kthread.h> > #include "ibmphp.h" > > @@ -88,10 +88,10 @@ static int to_debug = 0; > //---------------------------------------------------------------------------- > // global variables > //---------------------------------------------------------------------------- > -static struct mutex sem_hpcaccess; // lock access to HPC > -static struct semaphore semOperations; // lock all operations and > +static DEFINE_MUTEX(sem_hpcaccess); // lock access to HPC > +static DEFINE_MUTEX(operations_mutex); // lock all operations and > // access to data structures > -static struct semaphore sem_exit; // make sure polling thread goes away > +static DECLARE_COMPLETION(exit_complete); // make sure polling thread goes away > static struct task_struct *ibmphp_poll_thread; > //---------------------------------------------------------------------------- > // local function prototypes > @@ -109,23 +109,6 @@ static int hpc_wait_ctlr_notworking(int, struct controller *, void __iomem *, u8 > //---------------------------------------------------------------------------- > > > -/*---------------------------------------------------------------------- > -* Name: ibmphp_hpc_initvars > -* > -* Action: initialize semaphores and variables > -*---------------------------------------------------------------------*/ > -void __init ibmphp_hpc_initvars(void) > -{ > - debug("%s - Entry\n", __func__); > - > - mutex_init(&sem_hpcaccess); > - sema_init(&semOperations, 1); > - sema_init(&sem_exit, 0); > - to_debug = 0; > - > - debug("%s - Exit\n", __func__); > -} > - > /*---------------------------------------------------------------------- > * Name: i2c_ctrl_read > * > @@ -780,7 +763,7 @@ void free_hpc_access(void) > *---------------------------------------------------------------------*/ > void ibmphp_lock_operations(void) > { > - down(&semOperations); > + mutex_lock(&operations_mutex); > to_debug = 1; > } > > @@ -790,7 +773,7 @@ void ibmphp_lock_operations(void) > void ibmphp_unlock_operations(void) > { > debug("%s - Entry\n", __func__); > - up(&semOperations); > + mutex_unlock(&operations_mutex); > to_debug = 0; > debug("%s - Exit\n", __func__); > } > @@ -816,7 +799,7 @@ static int poll_hpc(void *data) > > while (!kthread_should_stop()) { > /* try to get the lock to do some kind of hardware access */ > - down(&semOperations); > + mutex_lock(&operations_mutex); > > switch (poll_state) { > case POLL_LATCH_REGISTER: > @@ -871,13 +854,13 @@ static int poll_hpc(void *data) > break; > case POLL_SLEEP: > /* don't sleep with a lock on the hardware */ > - up(&semOperations); > + mutex_unlock(&operations_mutex); > msleep(POLL_INTERVAL_SEC * 1000); > > if (kthread_should_stop()) > goto out_sleep; > > - down(&semOperations); > + mutex_lock(&operations_mutex); > > if (poll_count >= POLL_LATCH_CNT) { > poll_count = 0; > @@ -887,12 +870,12 @@ static int poll_hpc(void *data) > break; > } > /* give up the hardware semaphore */ > - up(&semOperations); > + mutex_unlock(&operations_mutex); > /* sleep for a short time just for good measure */ > out_sleep: > msleep(100); > } > - up(&sem_exit); > + complete(&exit_complete); > debug("%s - Exit\n", __func__); > return 0; > } > @@ -1060,9 +1043,9 @@ void __exit ibmphp_hpc_stop_poll_thread(void) > debug("after locking operations\n"); > > // wait for poll thread to exit > - debug("before sem_exit down\n"); > - down(&sem_exit); > - debug("after sem_exit down\n"); > + debug("before exit_complete down\n"); > + wait_for_completion(&exit_complete); > + debug("after exit_completion down\n"); > > // cleanup > debug("before free_hpc_access\n"); > @@ -1070,8 +1053,6 @@ void __exit ibmphp_hpc_stop_poll_thread(void) > debug("after free_hpc_access\n"); > ibmphp_unlock_operations(); > debug("after unlock operations\n"); > - up(&sem_exit); > - debug("after sem exit up\n"); > > debug("%s - Exit\n", __func__); > } > -- > 2.20.0 >
diff --git a/drivers/pci/hotplug/ibmphp.h b/drivers/pci/hotplug/ibmphp.h index b89f850c3a4e..e90a4ebf6550 100644 --- a/drivers/pci/hotplug/ibmphp.h +++ b/drivers/pci/hotplug/ibmphp.h @@ -378,7 +378,6 @@ int ibmphp_add_pfmem_from_mem(struct resource_node *); struct bus_node *ibmphp_find_res_bus(u8); void ibmphp_print_test(void); /* for debugging purposes */ -void ibmphp_hpc_initvars(void); int ibmphp_hpc_readslot(struct slot *, u8, u8 *); int ibmphp_hpc_writeslot(struct slot *, u8); void ibmphp_lock_operations(void); diff --git a/drivers/pci/hotplug/ibmphp_core.c b/drivers/pci/hotplug/ibmphp_core.c index 5752b57198e3..e04b17d81e38 100644 --- a/drivers/pci/hotplug/ibmphp_core.c +++ b/drivers/pci/hotplug/ibmphp_core.c @@ -1312,8 +1312,6 @@ static int __init ibmphp_init(void) ibmphp_debug = debug; - ibmphp_hpc_initvars(); - for (i = 0; i < 16; i++) irqs[i] = 0; diff --git a/drivers/pci/hotplug/ibmphp_hpc.c b/drivers/pci/hotplug/ibmphp_hpc.c index 752c384cbd4c..508a62a6b5f9 100644 --- a/drivers/pci/hotplug/ibmphp_hpc.c +++ b/drivers/pci/hotplug/ibmphp_hpc.c @@ -15,13 +15,13 @@ #include <linux/wait.h> #include <linux/time.h> +#include <linux/completion.h> #include <linux/delay.h> #include <linux/module.h> #include <linux/pci.h> #include <linux/init.h> #include <linux/mutex.h> #include <linux/sched.h> -#include <linux/semaphore.h> #include <linux/kthread.h> #include "ibmphp.h" @@ -88,10 +88,10 @@ static int to_debug = 0; //---------------------------------------------------------------------------- // global variables //---------------------------------------------------------------------------- -static struct mutex sem_hpcaccess; // lock access to HPC -static struct semaphore semOperations; // lock all operations and +static DEFINE_MUTEX(sem_hpcaccess); // lock access to HPC +static DEFINE_MUTEX(operations_mutex); // lock all operations and // access to data structures -static struct semaphore sem_exit; // make sure polling thread goes away +static DECLARE_COMPLETION(exit_complete); // make sure polling thread goes away static struct task_struct *ibmphp_poll_thread; //---------------------------------------------------------------------------- // local function prototypes @@ -109,23 +109,6 @@ static int hpc_wait_ctlr_notworking(int, struct controller *, void __iomem *, u8 //---------------------------------------------------------------------------- -/*---------------------------------------------------------------------- -* Name: ibmphp_hpc_initvars -* -* Action: initialize semaphores and variables -*---------------------------------------------------------------------*/ -void __init ibmphp_hpc_initvars(void) -{ - debug("%s - Entry\n", __func__); - - mutex_init(&sem_hpcaccess); - sema_init(&semOperations, 1); - sema_init(&sem_exit, 0); - to_debug = 0; - - debug("%s - Exit\n", __func__); -} - /*---------------------------------------------------------------------- * Name: i2c_ctrl_read * @@ -780,7 +763,7 @@ void free_hpc_access(void) *---------------------------------------------------------------------*/ void ibmphp_lock_operations(void) { - down(&semOperations); + mutex_lock(&operations_mutex); to_debug = 1; } @@ -790,7 +773,7 @@ void ibmphp_lock_operations(void) void ibmphp_unlock_operations(void) { debug("%s - Entry\n", __func__); - up(&semOperations); + mutex_unlock(&operations_mutex); to_debug = 0; debug("%s - Exit\n", __func__); } @@ -816,7 +799,7 @@ static int poll_hpc(void *data) while (!kthread_should_stop()) { /* try to get the lock to do some kind of hardware access */ - down(&semOperations); + mutex_lock(&operations_mutex); switch (poll_state) { case POLL_LATCH_REGISTER: @@ -871,13 +854,13 @@ static int poll_hpc(void *data) break; case POLL_SLEEP: /* don't sleep with a lock on the hardware */ - up(&semOperations); + mutex_unlock(&operations_mutex); msleep(POLL_INTERVAL_SEC * 1000); if (kthread_should_stop()) goto out_sleep; - down(&semOperations); + mutex_lock(&operations_mutex); if (poll_count >= POLL_LATCH_CNT) { poll_count = 0; @@ -887,12 +870,12 @@ static int poll_hpc(void *data) break; } /* give up the hardware semaphore */ - up(&semOperations); + mutex_unlock(&operations_mutex); /* sleep for a short time just for good measure */ out_sleep: msleep(100); } - up(&sem_exit); + complete(&exit_complete); debug("%s - Exit\n", __func__); return 0; } @@ -1060,9 +1043,9 @@ void __exit ibmphp_hpc_stop_poll_thread(void) debug("after locking operations\n"); // wait for poll thread to exit - debug("before sem_exit down\n"); - down(&sem_exit); - debug("after sem_exit down\n"); + debug("before exit_complete down\n"); + wait_for_completion(&exit_complete); + debug("after exit_completion down\n"); // cleanup debug("before free_hpc_access\n"); @@ -1070,8 +1053,6 @@ void __exit ibmphp_hpc_stop_poll_thread(void) debug("after free_hpc_access\n"); ibmphp_unlock_operations(); debug("after unlock operations\n"); - up(&sem_exit); - debug("after sem exit up\n"); debug("%s - Exit\n", __func__); }
The sem_exit variable is conceptually a completion, so it should be called that. Similarly, the semOperations semaphore is a simple mutex, and can be changed into that, respectively. With both converted, the ibmphp_hpc_initvars() function is no longer used and can be removed. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/pci/hotplug/ibmphp.h | 1 - drivers/pci/hotplug/ibmphp_core.c | 2 -- drivers/pci/hotplug/ibmphp_hpc.c | 47 +++++++++---------------------- 3 files changed, 14 insertions(+), 36 deletions(-) -- 2.20.0