From ee0e41355d1faa5f74085effc4f57c3a7fc1f884 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Thu, 4 Aug 2016 10:20:29 +0200 Subject: score: Fix a release/cancel job race condition Split up the potential thread priority change in the scheduler release/cancel job operation. Protect the rate monotonic period state with a dedicated SMP lock. This avoids a race condition during _Rate_monotonic_Timeout() while _Rate_monotonic_Cancel() is called on another processor. --- cpukit/rtems/src/ratemonperiod.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) (limited to 'cpukit/rtems/src/ratemonperiod.c') diff --git a/cpukit/rtems/src/ratemonperiod.c b/cpukit/rtems/src/ratemonperiod.c index 303fe174e5..75a80d8088 100644 --- a/cpukit/rtems/src/ratemonperiod.c +++ b/cpukit/rtems/src/ratemonperiod.c @@ -71,21 +71,20 @@ static void _Rate_monotonic_Release_job( ) { Per_CPU_Control *cpu_self; - uint64_t deadline; + Thread_Control *update_priority; + uint64_t deadline; cpu_self = _Thread_Dispatch_disable_critical( lock_context ); - _Rate_monotonic_Release( owner, lock_context ); - _ISR_lock_ISR_disable( lock_context ); deadline = _Watchdog_Per_CPU_insert_relative( &the_period->Timer, cpu_self, next_length ); - _ISR_lock_ISR_enable( lock_context ); - - _Scheduler_Release_job( owner, deadline ); + update_priority = _Scheduler_Release_job( owner, deadline ); + _Rate_monotonic_Release( the_period, lock_context ); + _Thread_Update_priority( update_priority ); _Thread_Dispatch_enable( cpu_self ); } @@ -217,7 +216,7 @@ static rtems_status_code _Rate_monotonic_Block_while_active( _Thread_Wait_flags_set( executing, RATE_MONOTONIC_INTEND_TO_BLOCK ); cpu_self = _Thread_Dispatch_disable_critical( lock_context ); - _Rate_monotonic_Release( executing, lock_context ); + _Rate_monotonic_Release( the_period, lock_context ); _Thread_Set_state( executing, STATES_WAITING_FOR_PERIOD ); @@ -278,13 +277,13 @@ rtems_status_code rtems_rate_monotonic_period( return RTEMS_NOT_OWNER_OF_RESOURCE; } - _Rate_monotonic_Acquire_critical( executing, &lock_context ); + _Rate_monotonic_Acquire_critical( the_period, &lock_context ); state = the_period->state; if ( length == RTEMS_PERIOD_STATUS ) { status = _Rate_monotonic_Get_status_for_state( state ); - _Rate_monotonic_Release( executing, &lock_context ); + _Rate_monotonic_Release( the_period, &lock_context ); } else { switch ( state ) { case RATE_MONOTONIC_ACTIVE: -- cgit v1.2.3