Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Feature/smp granular locks v4 #1154

Open
wants to merge 10 commits into
base: main
Choose a base branch
from
+1,662 −480
Open

Feature/smp granular locks v4 #1154

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
10 commits
Select commit Hold shift + click to select a range
6d9eae9
refactor(freertos/smp): Move critical sections inside xTaskPriorityIn…
Dazza0 Jun 15, 2024
5d7b54a
feat(freertos/smp): Allow vTaskPreemptionEnable() to be nested
Dazza0 Jun 15, 2024
abf1033
feat(freertos/smp): Add granular locking port macros checks
Dazza0 Jun 15, 2024
1ab110f
feat(granular_locks): Add granular locking functions
Dazza0 Jun 15, 2024
9fe8bde
change(freertos/smp): Update tasks.c locking
Dazza0 Jun 15, 2024
3733a10
change(freertos/smp): Update queue.c locking
Dazza0 Jun 15, 2024
268fa4d
change(freertos/smp): Update event_groups.c locking
Dazza0 Jun 15, 2024
cf960f6
change(freertos/smp): Update stream_buffer.c locking
Dazza0 Jun 15, 2024
795f081
change(freertos/smp): Update timers.c locking
Dazza0 Jun 15, 2024
4cf3837
feat(freertos/smp): Add Granular Locking V4 proposal documents
Dazza0 Jun 17, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
163 changes: 146 additions & 17 deletions event_groups.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -63,10 +63,48 @@
#if ( ( configSUPPORT_STATIC_ALLOCATION == 1 ) && ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) )
uint8_t ucStaticallyAllocated; /**< Set to pdTRUE if the event group is statically allocated to ensure no attempt is made to free the memory. */
#endif

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
portSPINLOCK_TYPE xTaskSpinlock;
portSPINLOCK_TYPE xISRSpinlock;
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
} EventGroup_t;

/*-----------------------------------------------------------*/

/*
* Macros to mark the start and end of a critical code region.
*/
#if ( portUSING_GRANULAR_LOCKS == 1 )
#define event_groupsENTER_CRITICAL( pxEventBits ) portENTER_CRITICAL_DATA_GROUP( ( portSPINLOCK_TYPE * ) &( pxEventBits->xTaskSpinlock ), &( pxEventBits->xISRSpinlock ) )
#define event_groupsENTER_CRITICAL_FROM_ISR( pxEventBits ) portENTER_CRITICAL_DATA_GROUP_FROM_ISR( ( portSPINLOCK_TYPE * ) &( pxEventBits->xISRSpinlock ) )
#define event_groupsEXIT_CRITICAL( pxEventBits ) portEXIT_CRITICAL_DATA_GROUP( ( portSPINLOCK_TYPE * ) &( pxEventBits->xTaskSpinlock ), &( pxEventBits->xISRSpinlock ) )
#define event_groupsEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus, pxEventBits ) portEXIT_CRITICAL_DATA_GROUP_FROM_ISR( uxSavedInterruptStatus, ( portSPINLOCK_TYPE * ) &( pxEventBits->xISRSpinlock ) )
#else /* #if ( portUSING_GRANULAR_LOCKS == 1 ) */
#define event_groupsENTER_CRITICAL( pxEventBits ) do { ( void ) pxEventBits; taskENTER_CRITICAL(); } while( 0 )
#define event_groupsENTER_CRITICAL_FROM_ISR( pxEventBits ) do { ( void ) pxEventBits; taskENTER_CRITICAL_FROM_ISR(); } while( 0 )
#define event_groupsEXIT_CRITICAL( pxEventBits ) do { ( void ) pxEventBits; taskEXIT_CRITICAL(); } while( 0 )
#define event_groupsEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus, pxEventBits ) do { ( void ) pxEventBits; taskEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus ); } while( 0 )
#endif /* #if ( portUSING_GRANULAR_LOCKS == 1 ) */

/*
* Locks an event group for tasks. Prevents other tasks from accessing the event group but allows
* ISRs to pend access to the event group. Caller cannot be preempted by other tasks
* after locking the event group, thus allowing the caller to execute non-deterministic
* operations.
*/
#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
static void prvLockEventGroupForTasks( EventGroup_t * pxEventBits ) PRIVILEGED_FUNCTION;
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

/*
* Unlocks an event group for tasks. Handles all pended access from ISRs, then reenables
* preemption for the caller.
*/
#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
static BaseType_t prvUnlockEventGroupForTasks( EventGroup_t * pxEventBits ) PRIVILEGED_FUNCTION;
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

/*
* Test the bits set in uxCurrentEventBits to see if the wait condition is met.
* The wait condition is defined by xWaitForAllBits. If xWaitForAllBits is
Expand All @@ -79,6 +117,25 @@
const EventBits_t uxBitsToWaitFor,
const BaseType_t xWaitForAllBits ) PRIVILEGED_FUNCTION;

/*-----------------------------------------------------------*/

/*
* Macros used to lock and unlock an event group. When a task lockss an,
* event group, the task will have thread safe non-deterministic access to
* the event group.
* - Concurrent access from other tasks will be blocked by the xTaskSpinlock
* - Concurrent access from ISRs will be pended
*
* When the task unlocks the event group, all pended access attempts are handled.
*/
#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
sudeep-mohanty marked this conversation as resolved.
Show resolved Hide resolved
#define event_groupsLOCK( pxEventBits ) prvLockEventGroupForTasks( pxEventBits )
#define event_groupsUNLOCK( pxEventBits ) prvUnlockEventGroupForTasks( pxEventBits );
#else /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
#define event_groupsLOCK( pxEventBits ) vTaskSuspendAll()
#define event_groupsUNLOCK( pxEventBits ) xTaskResumeAll()
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

/*-----------------------------------------------------------*/

#if ( configSUPPORT_STATIC_ALLOCATION == 1 )
Expand Down Expand Up @@ -122,6 +179,13 @@
}
#endif /* configSUPPORT_DYNAMIC_ALLOCATION */

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
{
portINIT_SPINLOCK( &( pxEventBits->xTaskSpinlock ) );
portINIT_SPINLOCK( &( pxEventBits->xISRSpinlock ) );
}
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

traceEVENT_GROUP_CREATE( pxEventBits );
}
else
Expand Down Expand Up @@ -167,6 +231,13 @@
}
#endif /* configSUPPORT_STATIC_ALLOCATION */

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
{
portINIT_SPINLOCK( &( pxEventBits->xTaskSpinlock ) );
portINIT_SPINLOCK( &( pxEventBits->xISRSpinlock ) );
}
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

traceEVENT_GROUP_CREATE( pxEventBits );
}
else
Expand Down Expand Up @@ -202,7 +273,7 @@
}
#endif

vTaskSuspendAll();
event_groupsLOCK( pxEventBits );
{
uxOriginalBitValue = pxEventBits->uxEventBits;

Expand Down Expand Up @@ -245,7 +316,7 @@
}
}
}
xAlreadyYielded = xTaskResumeAll();
xAlreadyYielded = event_groupsUNLOCK( pxEventBits );

if( xTicksToWait != ( TickType_t ) 0 )
{
Expand All @@ -267,7 +338,7 @@
if( ( uxReturn & eventUNBLOCKED_DUE_TO_BIT_SET ) == ( EventBits_t ) 0 )
{
/* The task timed out, just return the current event bit value. */
taskENTER_CRITICAL();
event_groupsENTER_CRITICAL( pxEventBits );
{
uxReturn = pxEventBits->uxEventBits;

Expand All @@ -284,7 +355,7 @@
mtCOVERAGE_TEST_MARKER();
}
}
taskEXIT_CRITICAL();
event_groupsEXIT_CRITICAL( pxEventBits );

xTimeoutOccurred = pdTRUE;
}
Expand Down Expand Up @@ -333,7 +404,7 @@
}
#endif

vTaskSuspendAll();
event_groupsLOCK( pxEventBits );
{
const EventBits_t uxCurrentEventBits = pxEventBits->uxEventBits;

Expand Down Expand Up @@ -401,7 +472,7 @@
traceEVENT_GROUP_WAIT_BITS_BLOCK( xEventGroup, uxBitsToWaitFor );
}
}
xAlreadyYielded = xTaskResumeAll();
xAlreadyYielded = event_groupsUNLOCK( pxEventBits );

if( xTicksToWait != ( TickType_t ) 0 )
{
Expand All @@ -422,7 +493,7 @@

if( ( uxReturn & eventUNBLOCKED_DUE_TO_BIT_SET ) == ( EventBits_t ) 0 )
{
taskENTER_CRITICAL();
event_groupsENTER_CRITICAL( pxEventBits );
{
/* The task timed out, just return the current event bit value. */
uxReturn = pxEventBits->uxEventBits;
Expand All @@ -447,7 +518,7 @@

xTimeoutOccurred = pdTRUE;
}
taskEXIT_CRITICAL();
event_groupsEXIT_CRITICAL( pxEventBits );
}
else
{
Expand Down Expand Up @@ -482,7 +553,7 @@
configASSERT( xEventGroup );
configASSERT( ( uxBitsToClear & eventEVENT_BITS_CONTROL_BYTES ) == 0 );

taskENTER_CRITICAL();
event_groupsENTER_CRITICAL( pxEventBits );
{
traceEVENT_GROUP_CLEAR_BITS( xEventGroup, uxBitsToClear );

Expand All @@ -493,7 +564,7 @@
/* Clear the bits. */
pxEventBits->uxEventBits &= ~uxBitsToClear;
}
taskEXIT_CRITICAL();
event_groupsEXIT_CRITICAL( pxEventBits );

traceRETURN_xEventGroupClearBits( uxReturn );

Expand Down Expand Up @@ -524,19 +595,19 @@
EventBits_t xEventGroupGetBitsFromISR( EventGroupHandle_t xEventGroup )
{
UBaseType_t uxSavedInterruptStatus;
EventGroup_t const * const pxEventBits = xEventGroup;
EventGroup_t * const pxEventBits = xEventGroup;
EventBits_t uxReturn;

traceENTER_xEventGroupGetBitsFromISR( xEventGroup );

/* MISRA Ref 4.7.1 [Return value shall be checked] */
/* More details at: https://github.com/FreeRTOS/FreeRTOS-Kernel/blob/main/MISRA.md#dir-47 */
/* coverity[misra_c_2012_directive_4_7_violation] */
uxSavedInterruptStatus = taskENTER_CRITICAL_FROM_ISR();
uxSavedInterruptStatus = event_groupsENTER_CRITICAL_FROM_ISR( pxEventBits );
{
uxReturn = pxEventBits->uxEventBits;
}
taskEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus );
event_groupsEXIT_CRITICAL_FROM_ISR( uxSavedInterruptStatus, pxEventBits );

traceRETURN_xEventGroupGetBitsFromISR( uxReturn );

Expand Down Expand Up @@ -564,10 +635,17 @@

pxList = &( pxEventBits->xTasksWaitingForBits );
pxListEnd = listGET_END_MARKER( pxList );
vTaskSuspendAll();
event_groupsLOCK( pxEventBits );
{
traceEVENT_GROUP_SET_BITS( xEventGroup, uxBitsToSet );

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )

/* We are about to access the kernel data group non-deterministically,
* thus we suspend the kernel data group.*/
vTaskSuspendAll();
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

pxListItem = listGET_HEAD_ENTRY( pxList );

/* Set the bits. */
Expand Down Expand Up @@ -638,8 +716,12 @@

/* Snapshot resulting bits. */
uxReturnBits = pxEventBits->uxEventBits;

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
( void ) xTaskResumeAll();
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
}
( void ) xTaskResumeAll();
( void ) event_groupsUNLOCK( pxEventBits );

traceRETURN_xEventGroupSetBits( uxReturnBits );

Expand All @@ -658,19 +740,30 @@

pxTasksWaitingForBits = &( pxEventBits->xTasksWaitingForBits );

vTaskSuspendAll();
event_groupsLOCK( pxEventBits );
{
traceEVENT_GROUP_DELETE( xEventGroup );

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )

/* We are about to access the kernel data group non-deterministically,
* thus we suspend the kernel data group.*/
vTaskSuspendAll();
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */

while( listCURRENT_LIST_LENGTH( pxTasksWaitingForBits ) > ( UBaseType_t ) 0 )
{
/* Unblock the task, returning 0 as the event list is being deleted
* and cannot therefore have any bits set. */
configASSERT( pxTasksWaitingForBits->xListEnd.pxNext != ( const ListItem_t * ) &( pxTasksWaitingForBits->xListEnd ) );
vTaskRemoveFromUnorderedEventList( pxTasksWaitingForBits->xListEnd.pxNext, eventUNBLOCKED_DUE_TO_BIT_SET );
}

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
( void ) xTaskResumeAll();
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
}
( void ) xTaskResumeAll();
( void ) event_groupsUNLOCK( pxEventBits );

#if ( ( configSUPPORT_DYNAMIC_ALLOCATION == 1 ) && ( configSUPPORT_STATIC_ALLOCATION == 0 ) )
{
Expand Down Expand Up @@ -775,6 +868,42 @@
}
/*-----------------------------------------------------------*/

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
static void prvLockEventGroupForTasks( EventGroup_t * pxEventBits )
{
/* Disable preemption so that the current task cannot be preempted by another task */
vTaskPreemptionDisable( NULL );

portDISABLE_INTERRUPTS();

/* Keep holding xTaskSpinlock to prevent tasks on other cores from accessing
* the event group while it is suspended. */
portGET_SPINLOCK( portGET_CORE_ID(), &( pxEventBits->xTaskSpinlock ) );

portENABLE_INTERRUPTS();
Comment on lines +877 to +883
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

portGET_SPINLOCK supposed to be thread safe then we can remove the disable/enable interrupts call here.

}
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
/*-----------------------------------------------------------*/

#if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) )
static BaseType_t prvUnlockEventGroupForTasks( EventGroup_t * pxEventBits )
{
portDISABLE_INTERRUPTS();

/* Release the previously held task spinlock */
portRELEASE_SPINLOCK( portGET_CORE_ID(), &( pxEventBits->xTaskSpinlock ) );

portENABLE_INTERRUPTS();

/* Re-enable preemption */
vTaskPreemptionEnable( NULL );

/* We assume that the task was preempted when preemption was enabled */
return pdTRUE;
}
#endif /* #if ( ( portUSING_GRANULAR_LOCKS == 1 ) && ( configNUMBER_OF_CORES > 1 ) ) */
/*-----------------------------------------------------------*/

static BaseType_t prvTestWaitCondition( const EventBits_t uxCurrentEventBits,
const EventBits_t uxBitsToWaitFor,
const BaseType_t xWaitForAllBits )
Expand Down
Loading