diff options
Diffstat (limited to 'cpukit')
| -rw-r--r-- | cpukit/rtems/ChangeLog | 5 | ||||
| -rw-r--r-- | cpukit/rtems/include/rtems/rtems/timer.h | 3 | ||||
| -rw-r--r-- | cpukit/rtems/src/timerserver.c | 52 |
3 files changed, 41 insertions, 19 deletions
diff --git a/cpukit/rtems/ChangeLog b/cpukit/rtems/ChangeLog index d2b8e2087f..d7c765775b 100644 --- a/cpukit/rtems/ChangeLog +++ b/cpukit/rtems/ChangeLog @@ -1,3 +1,8 @@ +2001-01-22 Joel Sherrill <joel@OARcorp.com> + + * include/rtems/rtems/timer.h, src/timerserver.c: Add priority + argument to rtems_timer_initiate_server(). + 2001-01-18 Joel Sherrill <joel@OARcorp.com> * include/rtems/system.h: Only include cpuopts.h when building a diff --git a/cpukit/rtems/include/rtems/rtems/timer.h b/cpukit/rtems/include/rtems/rtems/timer.h index 8f9b765037..58d40b3e05 100644 --- a/cpukit/rtems/include/rtems/rtems/timer.h +++ b/cpukit/rtems/include/rtems/rtems/timer.h @@ -310,7 +310,10 @@ rtems_status_code rtems_timer_reset( * It must be invoked before any task-based timers can be initiated. */ +#define RTEMS_TIMER_SERVER_DEFAULT_PRIORITY -1 + rtems_status_code rtems_timer_initiate_server( + unsigned32 priority, unsigned32 stack_size, rtems_attribute attribute_set ); diff --git a/cpukit/rtems/src/timerserver.c b/cpukit/rtems/src/timerserver.c index 58c0ea9bf7..196cceb4f8 100644 --- a/cpukit/rtems/src/timerserver.c +++ b/cpukit/rtems/src/timerserver.c @@ -147,8 +147,9 @@ Thread _Timer_Server_body( * It must be invoked before any task-based timers can be initiated. * * Input parameters: + * priority - timer server priority * stack_size - stack size in bytes - * attribute_set - thread attributes + * attribute_set - timer server attributes * * Output parameters: * RTEMS_SUCCESSFUL - if successful @@ -157,12 +158,24 @@ Thread _Timer_Server_body( rtems_status_code rtems_timer_initiate_server( + unsigned32 priority, unsigned32 stack_size, rtems_attribute attribute_set ) { - rtems_id id; - rtems_status_code status; + rtems_id id; + rtems_status_code status; + rtems_task_priority _priority; + + /* + * Make sure the requested priority is valid. + */ + + _priority = priority; + if ( priority == RTEMS_TIMER_SERVER_DEFAULT_PRIORITY ) + _priority = 0; + else if ( !_RTEMS_tasks_Priority_is_valid( priority ) ) + return RTEMS_INVALID_PRIORITY; /* * Just to make sure the test versus create/start operation are atomic. @@ -176,17 +189,28 @@ rtems_status_code rtems_timer_initiate_server( } /* - * Create the Timer Server with the name the name of "TIME". The priority - * is always "0" which makes it higher than any other task in the system. - * It is also always NO_PREEMPT so it looks like an interrupt to other tasks. + * Create the Timer Server with the name the name of "TIME". The attribute + * RTEMS_SYSTEM_TASK allows us to set a priority to 0 which will makes it + * higher than any other task in the system. It can be viewed as a low + * priority interrupt. It is also always NO_PREEMPT so it looks like + * an interrupt to other tasks. + * + * We allow the user to override the default priority because the Timer + * Server can invoke TSRs which must adhere to language run-time or + * other library rules. For example, if using a TSR written in Ada the + * Server should run at the same priority as the priority Ada task. + * Otherwise, the priority ceiling for the mutex used to protect the + * GNAT run-time is violated. */ status = rtems_task_create( - rtems_build_name( 'T', 'I', 'M', 'E' ), - 1, /* create with priority 1 since 0 is illegal */ + 0x4954454d, /* "TIME" */ + _priority, /* create with priority 1 since 0 is illegal */ stack_size, /* let user specify stack size */ RTEMS_NO_PREEMPT, /* no preempt is like an interrupt */ - attribute_set, /* user may want floating point */ + /* user may want floating point but we need */ + /* system task specified for 0 priority */ + attribute_set | RTEMS_SYSTEM_TASK, &id /* get the id back */ ); if (status) { @@ -225,16 +249,6 @@ rtems_status_code rtems_timer_initiate_server( ); /* - * A priority of 0, higher than any user task, combined with no preemption - * makes this task the highest priority in any application. It can be - * viewed as a low priority interrupt. The FALSE argument indicates - * that the task is to be appended (not prepended) to its priority - * chain at the end of this operation. - */ - - _Thread_Change_priority( _Timer_Server, 0, FALSE ); - - /* * Initialize the timer lists that the server will manage. */ |