[PATCH 1/3] rtems: Avoid Giant lock for signals
Sebastian Huber
sebastian.huber at embedded-brains.de
Wed May 4 09:35:09 UTC 2016
Update #2555.
---
cpukit/rtems/include/rtems/rtems/asr.h | 2 +-
cpukit/rtems/include/rtems/rtems/asrimpl.h | 66 ++++++++----------------
cpukit/rtems/include/rtems/rtems/signalmp.h | 31 ++---------
cpukit/rtems/src/signalcatch.c | 12 ++---
cpukit/rtems/src/signalmp.c | 79 ++++++++++++++++-------------
cpukit/rtems/src/signalsend.c | 74 +++++++++++++--------------
cpukit/rtems/src/taskmode.c | 4 +-
7 files changed, 115 insertions(+), 153 deletions(-)
diff --git a/cpukit/rtems/include/rtems/rtems/asr.h b/cpukit/rtems/include/rtems/rtems/asr.h
index 0110a40..4563750 100644
--- a/cpukit/rtems/include/rtems/rtems/asr.h
+++ b/cpukit/rtems/include/rtems/rtems/asr.h
@@ -76,7 +76,7 @@ typedef struct {
/** This field indicates if nest level of signals being processed */
uint32_t nest_level;
/** Lock to protect this structure */
- ISR_lock_Control Lock;
+ ISR_LOCK_MEMBER( Lock )
} ASR_Information;
/*
diff --git a/cpukit/rtems/include/rtems/rtems/asrimpl.h b/cpukit/rtems/include/rtems/rtems/asrimpl.h
index 7c1c648..892c58c 100644
--- a/cpukit/rtems/include/rtems/rtems/asrimpl.h
+++ b/cpukit/rtems/include/rtems/rtems/asrimpl.h
@@ -59,41 +59,29 @@ RTEMS_INLINE_ROUTINE void _ASR_Destroy( ASR_Information *asr )
_ISR_lock_Destroy( &asr->Lock );
}
-RTEMS_INLINE_ROUTINE void _ASR_Acquire(
+RTEMS_INLINE_ROUTINE void _ASR_Acquire_critical(
ASR_Information *asr,
ISR_lock_Context *lock_context
)
{
- _ISR_lock_ISR_disable_and_acquire( &asr->Lock, lock_context );
+ _ISR_lock_Acquire( &asr->Lock, lock_context );
}
-RTEMS_INLINE_ROUTINE void _ASR_Release(
+RTEMS_INLINE_ROUTINE void _ASR_Acquire(
ASR_Information *asr,
ISR_lock_Context *lock_context
)
{
- _ISR_lock_Release_and_ISR_enable( &asr->Lock, lock_context );
+ _ISR_lock_ISR_disable( lock_context );
+ _ASR_Acquire_critical( asr, lock_context );
}
-/**
- * @brief ASR_Swap_signals
- *
- * This routine atomically swaps the pending and posted signal
- * sets. This is done when the thread alters its mode in such a
- * way that the RTEMS_ASR disable/enable flag changes.
- */
-RTEMS_INLINE_ROUTINE void _ASR_Swap_signals (
- ASR_Information *asr
+RTEMS_INLINE_ROUTINE void _ASR_Release(
+ ASR_Information *asr,
+ ISR_lock_Context *lock_context
)
{
- rtems_signal_set _signals;
- ISR_lock_Context lock_context;
-
- _ASR_Acquire( asr, &lock_context );
- _signals = asr->signals_pending;
- asr->signals_pending = asr->signals_posted;
- asr->signals_posted = _signals;
- _ASR_Release( asr, &lock_context );
+ _ISR_lock_Release_and_ISR_enable( &asr->Lock, lock_context );
}
/**
@@ -109,38 +97,26 @@ RTEMS_INLINE_ROUTINE bool _ASR_Is_null_handler (
return asr_handler == NULL;
}
-/**
- * @brief ASR_Are_signals_pending
- *
- * This function returns TRUE if there are signals pending in the
- * given RTEMS_ASR information record and FALSE otherwise.
- */
-RTEMS_INLINE_ROUTINE bool _ASR_Are_signals_pending (
- ASR_Information *asr
-)
+RTEMS_INLINE_ROUTINE rtems_signal_set _ASR_Swap_signals( ASR_Information *asr )
{
- return asr->signals_posted != 0;
+ rtems_signal_set new_signals_posted;
+ ISR_lock_Context lock_context;
+
+ _ASR_Acquire( asr, &lock_context );
+ new_signals_posted = asr->signals_pending;
+ asr->signals_pending = asr->signals_posted;
+ asr->signals_posted = new_signals_posted;
+ _ASR_Release( asr, &lock_context );
+
+ return new_signals_posted;
}
-/**
- * @brief ASR_Post_signals
- *
- * This routine posts the given signals into the signal_set
- * passed in. The result is returned to the user in signal_set.
- *
- * NOTE: This must be implemented as a macro.
- */
RTEMS_INLINE_ROUTINE void _ASR_Post_signals(
- ASR_Information *asr,
rtems_signal_set signals,
rtems_signal_set *signal_set
)
{
- ISR_lock_Context lock_context;
-
- _ASR_Acquire( asr, &lock_context );
- *signal_set |= signals;
- _ASR_Release( asr, &lock_context );
+ *signal_set |= signals;
}
RTEMS_INLINE_ROUTINE rtems_signal_set _ASR_Get_posted_signals(
diff --git a/cpukit/rtems/include/rtems/rtems/signalmp.h b/cpukit/rtems/include/rtems/rtems/signalmp.h
index 2f85ac6..57b8682 100644
--- a/cpukit/rtems/include/rtems/rtems/signalmp.h
+++ b/cpukit/rtems/include/rtems/rtems/signalmp.h
@@ -38,25 +38,6 @@ extern "C" {
*/
/*{*/
-/**
- * The following enumerated type defines the list of
- * remote signal operations.
- */
-typedef enum {
- SIGNAL_MP_SEND_REQUEST = 0,
- SIGNAL_MP_SEND_RESPONSE = 1
-} Signal_MP_Remote_operations;
-
-/**
- * The following data structure defines the packet used to perform
- * remote signal operations.
- */
-typedef struct {
- rtems_packet_prefix Prefix;
- Signal_MP_Remote_operations operation;
- rtems_signal_set signal_in;
-} Signal_MP_Packet;
-
/*
* @brief Signal_MP_Send_process_packet
*
@@ -68,15 +49,11 @@ typedef struct {
*/
/**
- * @brief Signal MP Send Request Packet
- *
- * This routine performs a remote procedure call so that a
- * directive operation can be initiated on another node.
+ * @brief Issues a remote rtems_signal_send() request.
*/
-rtems_status_code _Signal_MP_Send_request_packet (
- Signal_MP_Remote_operations operation,
- Objects_Id task_id,
- rtems_signal_set signal_in
+rtems_status_code _Signal_MP_Send(
+ rtems_id id,
+ rtems_signal_set signal_set
);
/**
diff --git a/cpukit/rtems/src/signalcatch.c b/cpukit/rtems/src/signalcatch.c
index 7bf298d..73138a1 100644
--- a/cpukit/rtems/src/signalcatch.c
+++ b/cpukit/rtems/src/signalcatch.c
@@ -22,8 +22,6 @@
#include <rtems/rtems/signalimpl.h>
#include <rtems/rtems/asrimpl.h>
#include <rtems/rtems/tasks.h>
-#include <rtems/score/isrlevel.h>
-#include <rtems/score/threaddispatch.h>
#include <rtems/score/threadimpl.h>
void _Signal_Action_handler(
@@ -52,8 +50,9 @@ void _Signal_Action_handler(
asr = &api->Signal;
signal_set = _ASR_Get_posted_signals( asr );
- if ( !signal_set ) /* similar to _ASR_Are_signals_pending( asr ) */
+ if ( signal_set == 0 ) {
return;
+ }
asr->nest_level += 1;
rtems_task_mode( asr->mode_set, RTEMS_ALL_MODE_MASKS, &prev_mode );
@@ -74,11 +73,12 @@ rtems_status_code rtems_signal_catch(
ASR_Information *asr;
ISR_lock_Context lock_context;
- executing = _Thread_Get_executing();
- api = (RTEMS_API_Control*)executing->API_Extensions[ THREAD_API_RTEMS ];
+ _ISR_lock_ISR_disable( &lock_context );
+ executing = _Thread_Executing;
+ api = executing->API_Extensions[ THREAD_API_RTEMS ];
asr = &api->Signal;
- _ASR_Acquire( asr, &lock_context );
+ _ASR_Acquire_critical( asr, &lock_context );
if ( !_ASR_Is_null_handler( asr_handler ) ) {
asr->mode_set = mode_set;
diff --git a/cpukit/rtems/src/signalmp.c b/cpukit/rtems/src/signalmp.c
index 8c63c2f..cd89e9f 100644
--- a/cpukit/rtems/src/signalmp.c
+++ b/cpukit/rtems/src/signalmp.c
@@ -24,13 +24,36 @@
#include <rtems/score/threadimpl.h>
#include <rtems/score/threadqimpl.h>
+/**
+ * The following enumerated type defines the list of
+ * remote signal operations.
+ */
+typedef enum {
+ SIGNAL_MP_SEND_REQUEST = 0,
+ SIGNAL_MP_SEND_RESPONSE = 1
+} Signal_MP_Remote_operations;
+
+/**
+ * The following data structure defines the packet used to perform
+ * remote signal operations.
+ */
+typedef struct {
+ rtems_packet_prefix Prefix;
+ Signal_MP_Remote_operations operation;
+ rtems_signal_set signal_set;
+} Signal_MP_Packet;
+
RTEMS_STATIC_ASSERT(
sizeof(Signal_MP_Packet) <= MP_PACKET_MINIMUM_PACKET_SIZE,
Signal_MP_Packet
);
-static Signal_MP_Packet *_Signal_MP_Get_packet( void )
+static Signal_MP_Packet *_Signal_MP_Get_packet( Objects_Id id )
{
+ if ( !_Thread_MP_Is_remote( id ) ) {
+ return NULL;
+ }
+
return (Signal_MP_Packet *) _MPCI_Get_packet();
}
@@ -42,43 +65,31 @@ static Signal_MP_Packet *_Signal_MP_Get_packet( void )
*
*/
-rtems_status_code _Signal_MP_Send_request_packet (
- Signal_MP_Remote_operations operation,
- Objects_Id task_id,
- rtems_signal_set signal_in
+rtems_status_code _Signal_MP_Send(
+ rtems_id id,
+ rtems_signal_set signal_set
)
{
Signal_MP_Packet *the_packet;
- switch ( operation ) {
-
- case SIGNAL_MP_SEND_REQUEST:
-
- the_packet = _Signal_MP_Get_packet();
- the_packet->Prefix.the_class = MP_PACKET_SIGNAL;
- the_packet->Prefix.length = sizeof ( Signal_MP_Packet );
- the_packet->Prefix.to_convert = sizeof ( Signal_MP_Packet );
- the_packet->operation = operation;
- the_packet->Prefix.id = task_id;
- the_packet->signal_in = signal_in;
-
- return _MPCI_Send_request_packet(
- _Objects_Get_node( task_id ),
- &the_packet->Prefix,
- STATES_READY, /* Not used */
- RTEMS_TIMEOUT
- );
- break;
-
- case SIGNAL_MP_SEND_RESPONSE:
- break;
-
+ the_packet = _Signal_MP_Get_packet( id );
+ if ( the_packet == NULL ) {
+ return RTEMS_INVALID_ID;
}
- /*
- * The following line is included to satisfy compilers which
- * produce warnings when a function does not end with a return.
- */
- return RTEMS_INTERNAL_ERROR;
+
+ the_packet->Prefix.the_class = MP_PACKET_SIGNAL;
+ the_packet->Prefix.length = sizeof( *the_packet );
+ the_packet->Prefix.to_convert = sizeof( *the_packet );
+ the_packet->operation = SIGNAL_MP_SEND_REQUEST;
+ the_packet->Prefix.id = id;
+ the_packet->signal_set = signal_set;
+
+ return (rtems_status_code) _MPCI_Send_request_packet(
+ _Objects_Get_node( id ),
+ &the_packet->Prefix,
+ STATES_READY,
+ RTEMS_TIMEOUT
+ );
}
static void _Signal_MP_Send_response_packet (
@@ -127,7 +138,7 @@ void _Signal_MP_Process_packet (
the_packet->Prefix.return_code = rtems_signal_send(
the_packet->Prefix.id,
- the_packet->signal_in
+ the_packet->signal_set
);
_Signal_MP_Send_response_packet(
diff --git a/cpukit/rtems/src/signalsend.c b/cpukit/rtems/src/signalsend.c
index 4153e40..162de5c 100644
--- a/cpukit/rtems/src/signalsend.c
+++ b/cpukit/rtems/src/signalsend.c
@@ -21,7 +21,7 @@
#include <rtems/rtems/signalimpl.h>
#include <rtems/rtems/asrimpl.h>
#include <rtems/rtems/tasks.h>
-#include <rtems/score/isr.h>
+#include <rtems/score/threaddispatch.h>
#include <rtems/score/threadimpl.h>
rtems_status_code rtems_signal_send(
@@ -29,50 +29,48 @@ rtems_status_code rtems_signal_send(
rtems_signal_set signal_set
)
{
- Thread_Control *the_thread;
- Objects_Locations location;
- RTEMS_API_Control *api;
- ASR_Information *asr;
+ Thread_Control *the_thread;
+ ISR_lock_Context lock_context;
+ RTEMS_API_Control *api;
+ ASR_Information *asr;
- if ( !signal_set )
+ if ( signal_set == 0 ) {
return RTEMS_INVALID_NUMBER;
+ }
- the_thread = _Thread_Get( id, &location );
- switch ( location ) {
-
- case OBJECTS_LOCAL:
- api = the_thread->API_Extensions[ THREAD_API_RTEMS ];
- asr = &api->Signal;
-
- if ( ! _ASR_Is_null_handler( asr->handler ) ) {
- if ( asr->is_enabled ) {
- _ASR_Post_signals( asr, signal_set, &asr->signals_posted );
- _Thread_Add_post_switch_action(
- the_thread,
- &api->Signal_action,
- _Signal_Action_handler
- );
- } else {
- _ASR_Post_signals( asr, signal_set, &asr->signals_pending );
- }
- _Objects_Put( &the_thread->Object );
- return RTEMS_SUCCESSFUL;
- }
- _Objects_Put( &the_thread->Object );
- return RTEMS_NOT_DEFINED;
+ the_thread = _Thread_Get_interrupt_disable( id, &lock_context );
+ if ( the_thread == NULL ) {
#if defined(RTEMS_MULTIPROCESSING)
- case OBJECTS_REMOTE:
- return _Signal_MP_Send_request_packet(
- SIGNAL_MP_SEND_REQUEST,
- id,
- signal_set
- );
+ return _Signal_MP_Send( id, signal_set );
+#else
+ return RTEMS_INVALID_ID;
#endif
+ }
+
+ api = the_thread->API_Extensions[ THREAD_API_RTEMS ];
+ asr = &api->Signal;
+
+ _ASR_Acquire_critical( asr, &lock_context );
+
+ if ( _ASR_Is_null_handler( asr->handler ) ) {
+ _ASR_Release( asr, &lock_context );
+ return RTEMS_NOT_DEFINED;
+ }
- case OBJECTS_ERROR:
- break;
+ if ( asr->is_enabled ) {
+ _ASR_Post_signals( signal_set, &asr->signals_posted );
+ _ASR_Release( asr, &lock_context );
+ _Thread_Add_post_switch_action(
+ the_thread,
+ &api->Signal_action,
+ _Signal_Action_handler
+ );
+ _Thread_Dispatch();
+ } else {
+ _ASR_Post_signals( signal_set, &asr->signals_pending );
+ _ASR_Release( asr, &lock_context );
}
- return RTEMS_INVALID_ID;
+ return RTEMS_SUCCESSFUL;
}
diff --git a/cpukit/rtems/src/taskmode.c b/cpukit/rtems/src/taskmode.c
index 0fc0924..e2dc7ed 100644
--- a/cpukit/rtems/src/taskmode.c
+++ b/cpukit/rtems/src/taskmode.c
@@ -99,8 +99,8 @@ rtems_status_code rtems_task_mode(
if ( is_asr_enabled != asr->is_enabled ) {
asr->is_enabled = is_asr_enabled;
- _ASR_Swap_signals( asr );
- if ( _ASR_Are_signals_pending( asr ) ) {
+
+ if ( _ASR_Swap_signals( asr ) != 0 ) {
needs_asr_dispatching = true;
_Thread_Add_post_switch_action(
executing,
--
1.8.4.5
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