RTOS/rtems
1
0
Fork 0
forked from Imagelibrary/rtems
Code Pull Requests Activity

posix: Avoid Giant lock in sem_getvalue()

Browse Source 
Update #2555.
This commit is contained in:
Sebastian Huber
2016-04-20 06:15:07 +02:00
parent cca2d8abc4
commit b5a21bf139
1 changed files with 11 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
cpukit/posix/src/semgetvalue.c
View File

@@ -37,13 +37,22 @@ int sem_getvalue(
{
POSIX_Semaphore_Control *the_semaphore;
Objects_Locations location;
ISR_lock_Context lock_context;
the_semaphore = _POSIX_Semaphore_Get( sem, &location );
the_semaphore = _POSIX_Semaphore_Get_interrupt_disable(
sem,
&location,
&lock_context
);
switch ( location ) {
case OBJECTS_LOCAL:
/*
* Assume a relaxed atomic load of the value on SMP configurations.
* Thus, there is no need to acquire a lock.
*/
*sval = _CORE_semaphore_Get_count( &the_semaphore->Semaphore );
_Objects_Put( &the_semaphore->Object );
_ISR_lock_ISR_enable( &lock_context );
return 0;
#if defined(RTEMS_MULTIPROCESSING)