[PATCH 09/11] smp: Simplify SMP initialization sequence
Sebastian Huber
sebastian.huber at embedded-brains.de
Mon May 27 10:58:14 UTC 2013
Delete bsp_smp_wait_for(). Other parts of the system work without
timeout, e.g. the spinlocks. Using a timeout here does not make the
system more robust.
Delete bsp_smp_cpu_state and replace it with Per_CPU_State. The
Per_CPU_State follows the Score naming conventions. Add
_Per_CPU_Change_state() and _Per_CPU_Wait_for_state() functions to
change and observe states.
Use Per_CPU_State in Per_CPU_Control instead of the anonymous integer.
Add _CPU_Processor_event_broadcast() and _CPU_Processor_event_receive()
functions provided by the CPU port. Use these functions in
_Per_CPU_Change_state() and _Per_CPU_Wait_for_state().
Add prototype for _SMP_Send_message().
Delete RTEMS_BSP_SMP_FIRST_TASK message. The first context switch is
now performed in rtems_smp_secondary_cpu_initialize(). Issuing the
first context switch in the context of the inter-processor interrupt is
not possible on systems with a modern interrupt controller. Such an
interrupt controler usually requires a handshake protocol with interrupt
acknowledge and end of interrupt signals. A direct context switch in an
interrupt handler circumvents the interrupt processing epilogue and may
leave the system in an inconsistent state.
Release lock in rtems_smp_process_interrupt() even if no message was
delivered. This prevents deadlock of the system.
Simplify and format _SMP_Send_message(),
_SMP_Request_other_cores_to_perform_first_context_switch(),
_SMP_Request_other_cores_to_dispatch() and
_SMP_Request_other_cores_to_shutdown().
---
c/src/lib/libbsp/i386/shared/smp/smp-imps.c | 49 -----
c/src/lib/libbsp/shared/smp/bspsmp_wait_for.c | 28 ---
c/src/lib/libbsp/sparc/erc32/Makefile.am | 3 +-
c/src/lib/libbsp/sparc/leon2/Makefile.am | 3 +-
c/src/lib/libbsp/sparc/leon3/smp/smp_leon3.c | 29 +---
cpukit/score/cpu/i386/rtems/score/cpu.h | 10 +
cpukit/score/cpu/no_cpu/rtems/score/cpu.h | 31 +++
cpukit/score/cpu/sparc/rtems/score/cpu.h | 10 +
cpukit/score/include/rtems/bspsmp.h | 6 -
cpukit/score/include/rtems/score/percpu.h | 73 ++++++--
cpukit/score/include/rtems/score/smp.h | 17 +-
cpukit/score/src/percpu.c | 29 +++-
cpukit/score/src/smp.c | 243 +++++++++----------------
13 files changed, 242 insertions(+), 289 deletions(-)
delete mode 100644 c/src/lib/libbsp/shared/smp/bspsmp_wait_for.c
diff --git a/c/src/lib/libbsp/i386/shared/smp/smp-imps.c b/c/src/lib/libbsp/i386/shared/smp/smp-imps.c
index 62ce8ac..916379e 100644
--- a/c/src/lib/libbsp/i386/shared/smp/smp-imps.c
+++ b/c/src/lib/libbsp/i386/shared/smp/smp-imps.c
@@ -71,7 +71,6 @@
#define PHYS_TO_VIRTUAL(x) /* convert physical address "x" to virtual */
#define VIRTUAL_TO_PHYS(x) /* convert virtual address "x" to physical */
#define UDELAY(x) /* delay roughly at least "x" microsecs */
-#define TEST_BOOTED(x) /* test bootaddr x to see if CPU started */
#define READ_MSR_LO(x) /* Read MSR low function */
#else
#include <string.h>
@@ -125,9 +124,6 @@ static void UDELAY(int x)
#define READ_MSR_LO(_x) \
(unsigned int)(read_msr(_x) & 0xffffffff)
-#define TEST_BOOTED(_cpu) \
- (_Per_CPU_Information[_cpu].state == RTEMS_BSP_SMP_CPU_INITIALIZED)
-
static inline unsigned long long read_msr(unsigned int msr)
{
unsigned long long value;
@@ -311,22 +307,6 @@ boot_cpu(imps_processor *proc)
}
/*
- * Check to see if other processor has started.
- */
- bsp_smp_wait_for(
- (volatile unsigned int *)&_Per_CPU_Information[imps_num_cpus].state,
- RTEMS_BSP_SMP_CPU_INITIALIZED,
- 1600
- );
- if ( _Per_CPU_Information[imps_num_cpus].state ==
- RTEMS_BSP_SMP_CPU_INITIALIZED )
- printk("#%d Application Processor (AP)", imps_num_cpus);
- else {
- printk("CPU Not Responding, DISABLED");
- success = 0;
- }
-
- /*
* Generic CPU startup sequence ends here, the rest is cleanup.
*/
@@ -835,32 +815,3 @@ void bsp_smp_broadcast_interrupt(void)
/* Single broadcast interrupt */
send_ipi( 0, LAPIC_ICR_DS_ALLEX | 0x30 );
}
-
-void bsp_smp_wait_for(
- volatile unsigned int *address,
- unsigned int desired,
- int maximum_usecs
-)
-{
- int iterations;
- volatile int i;
- volatile unsigned int *p = (volatile unsigned int *)address;
-
- for (iterations=0 ; iterations < maximum_usecs ; iterations++ ) {
- if ( *p == desired )
- break;
- #ifdef __SSE3__
- __builtin_ia32_monitor( (const void *)address, 0, 0 );
- if ( *p == desired )
- break;
- __builtin_ia32_mwait( 0, 0 );
- #endif
-
- /*
- * Until i386 ms delay does not depend upon the clock we
- * will use this less sophisticated delay.
- */
- for(i=5000; i>0; i--)
- ;
- }
-}
diff --git a/c/src/lib/libbsp/shared/smp/bspsmp_wait_for.c b/c/src/lib/libbsp/shared/smp/bspsmp_wait_for.c
deleted file mode 100644
index 8c4dcf7..0000000
--- a/c/src/lib/libbsp/shared/smp/bspsmp_wait_for.c
+++ /dev/null
@@ -1,28 +0,0 @@
-/*
- *
- * COPYRIGHT (c) 1989-2011.
- * On-Line Applications Research Corporation (OAR).
- *
- * The license and distribution terms for this file may be
- * found in the file LICENSE in this distribution or at
- * http://www.rtems.com/license/LICENSE.
- */
-
-void rtems_bsp_delay( int usec );
-
-void bsp_smp_wait_for(
- volatile unsigned int *address,
- unsigned int desired,
- int maximum_usecs
-)
-{
- int iterations;
- volatile unsigned int *p = address;
-
- for (iterations=0 ; iterations < maximum_usecs ; iterations++ ) {
- if ( *p == desired )
- break;
-
- rtems_bsp_delay( 1 );
- }
-}
diff --git a/c/src/lib/libbsp/sparc/erc32/Makefile.am b/c/src/lib/libbsp/sparc/erc32/Makefile.am
index ddb8d94..988f3ec 100644
--- a/c/src/lib/libbsp/sparc/erc32/Makefile.am
+++ b/c/src/lib/libbsp/sparc/erc32/Makefile.am
@@ -66,8 +66,7 @@ libbsp_a_SOURCES += \
../../shared/src/irq-shell.c
if HAS_SMP
-libbsp_a_SOURCES += ../../shared/smp/getcpuid.c ../../shared/smp/smp_stub.c \
- ../../shared/smp/bspsmp_wait_for.c
+libbsp_a_SOURCES += ../../shared/smp/getcpuid.c ../../shared/smp/smp_stub.c
endif
if HAS_NETWORKING
diff --git a/c/src/lib/libbsp/sparc/leon2/Makefile.am b/c/src/lib/libbsp/sparc/leon2/Makefile.am
index 9699bf1..ae6dfb0 100644
--- a/c/src/lib/libbsp/sparc/leon2/Makefile.am
+++ b/c/src/lib/libbsp/sparc/leon2/Makefile.am
@@ -119,8 +119,7 @@ libbsp_a_SOURCES += ../../sparc/shared/i2c/i2cmst.c
libbsp_a_SOURCES += timer/timer.c
if HAS_SMP
-libbsp_a_SOURCES += ../../shared/smp/getcpuid.c ../../shared/smp/smp_stub.c \
- ../../shared/smp/bspsmp_wait_for.c
+libbsp_a_SOURCES += ../../shared/smp/getcpuid.c ../../shared/smp/smp_stub.c
endif
if HAS_NETWORKING
diff --git a/c/src/lib/libbsp/sparc/leon3/smp/smp_leon3.c b/c/src/lib/libbsp/sparc/leon3/smp/smp_leon3.c
index 6a9c189..9081819 100644
--- a/c/src/lib/libbsp/sparc/leon3/smp/smp_leon3.c
+++ b/c/src/lib/libbsp/sparc/leon3/smp/smp_leon3.c
@@ -33,7 +33,7 @@ static inline unsigned int sparc_leon3_get_cctrl( void )
return v;
}
-rtems_isr bsp_ap_ipi_isr(
+static rtems_isr bsp_ap_ipi_isr(
rtems_vector_number vector
)
{
@@ -99,10 +99,11 @@ uint32_t bsp_smp_initialize( uint32_t configured_cpu_count )
bsp_smp_delay( 1000000 );
#if defined(RTEMS_DEBUG)
printk(
- "CPU %d is %s\n",
- cpu,
- ((_Per_CPU_Information[cpu].state == RTEMS_BSP_SMP_CPU_INITIALIZED) ?
- "online" : "offline")
+ "CPU %d is %s\n",
+ cpu,
+ _Per_CPU_Information[cpu].state
+ == PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING ?
+ "online" : "offline"
);
#endif
}
@@ -160,21 +161,3 @@ void bsp_smp_delay( int max )
{
__delay( max );
}
-
-void bsp_smp_wait_for(
- volatile unsigned int *address,
- unsigned int desired,
- int maximum_usecs
-)
-{
- int iterations;
- volatile unsigned int *p = address;
-
- for (iterations=0 ; iterations < maximum_usecs ; iterations++ ) {
- if ( *p == desired )
- break;
- bsp_smp_delay( 5000 );
- }
-}
-
-
diff --git a/cpukit/score/cpu/i386/rtems/score/cpu.h b/cpukit/score/cpu/i386/rtems/score/cpu.h
index 6a19fb1..c262e3c 100644
--- a/cpukit/score/cpu/i386/rtems/score/cpu.h
+++ b/cpukit/score/cpu/i386/rtems/score/cpu.h
@@ -463,6 +463,16 @@ uint32_t _CPU_ISR_Get_level( void );
"1" (_value) : \
"cc"); \
} while (0)
+
+ static inline void _CPU_Processor_event_broadcast( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
+
+ static inline void _CPU_Processor_event_receive( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
#endif
#define _CPU_Context_Fp_start( _base, _offset ) \
diff --git a/cpukit/score/cpu/no_cpu/rtems/score/cpu.h b/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
index 6d72976..e2c6d94 100644
--- a/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
+++ b/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
@@ -1402,6 +1402,37 @@ static inline uint32_t CPU_swap_u32(
#define CPU_swap_u16( value ) \
(((value&0xff) << 8) | ((value >> 8)&0xff))
+#ifdef RTEMS_SMP
+ /**
+ * @brief Broadcasts a processor event.
+ *
+ * Some architectures provide a low-level synchronization primitive for
+ * processors in a multi-processor environment. Processors waiting for this
+ * event may go into a low-power state and stop generating system bus
+ * transactions. This function must ensure that preceding store operations
+ * can be observed by other processors.
+ *
+ * @see _CPU_Processor_event_receive().
+ */
+ static inline void _CPU_Processor_event_broadcast( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
+
+ /**
+ * @brief Receives a processor event.
+ *
+ * This function will wait for the processor event and may wait forever if no
+ * such event arrives.
+ *
+ * @see _CPU_Processor_event_broadcast().
+ */
+ static inline void _CPU_Processor_event_receive( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
+#endif
+
#ifdef __cplusplus
}
#endif
diff --git a/cpukit/score/cpu/sparc/rtems/score/cpu.h b/cpukit/score/cpu/sparc/rtems/score/cpu.h
index 2209c89..9654c29 100644
--- a/cpukit/score/cpu/sparc/rtems/score/cpu.h
+++ b/cpukit/score/cpu/sparc/rtems/score/cpu.h
@@ -1203,6 +1203,16 @@ void _CPU_Context_restore(
); \
_previous = _val; \
} while (0)
+
+ static inline void _CPU_Processor_event_broadcast( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
+
+ static inline void _CPU_Processor_event_receive( void )
+ {
+ __asm__ volatile ( "" : : : "memory" );
+ }
#endif
/**
diff --git a/cpukit/score/include/rtems/bspsmp.h b/cpukit/score/include/rtems/bspsmp.h
index 240f820..4806c90 100644
--- a/cpukit/score/include/rtems/bspsmp.h
+++ b/cpukit/score/include/rtems/bspsmp.h
@@ -148,12 +148,6 @@ void rtems_smp_secondary_cpu_initialize( void );
*/
void rtems_smp_process_interrupt(void);
-void bsp_smp_wait_for(
- volatile unsigned int *address,
- unsigned int desired,
- int maximum_usecs
-);
-
#endif
#ifdef __cplusplus
diff --git a/cpukit/score/include/rtems/score/percpu.h b/cpukit/score/include/rtems/score/percpu.h
index 5469d25..f8cc0c8 100644
--- a/cpukit/score/include/rtems/score/percpu.h
+++ b/cpukit/score/include/rtems/score/percpu.h
@@ -60,32 +60,57 @@ extern "C" {
typedef struct Thread_Control_struct Thread_Control;
#endif
+#ifdef RTEMS_SMP
+
typedef enum {
+ /**
+ * @brief The per CPU controls are initialized to zero.
+ *
+ * In this state the only valid field of the per CPU controls for secondary
+ * processors is the per CPU state. The secondary CPUs should perform their
+ * basic initialization now and change into the
+ * PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING state once this is complete.
+ */
+ PER_CPU_STATE_BEFORE_INITIALIZATION,
/**
- * This defines the constant used to indicate that the cpu code is in
- * its initial powered up start.
+ * @brief Secondary CPU is ready to begin multitasking.
+ *
+ * The secondary CPU performed its basic initialization and is ready to
+ * receive inter-processor interrupts. Interrupt delivery must be disabled
+ * in this state, but requested inter-processor interrupts must be recorded
+ * and must be delivered once the secondary CPU enables interrupts for the
+ * first time. The main CPU will wait for all secondary CPUs to change into
+ * this state. In case a secondary CPU does not reach this state the system
+ * will not start. The secondary CPUs wait now for a change into the
+ * PER_CPU_STATE_BEGIN_MULTITASKING state set by the main CPU once all
+ * secondary CPUs reached the PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING
+ * state.
*/
- RTEMS_BSP_SMP_CPU_INITIAL_STATE = 1,
+ PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING,
/**
- * This defines the constant used to indicate that the cpu code has
- * completed basic initialization and awaits further commands.
+ * @brief Multitasking begin of secondary CPU is requested.
+ *
+ * The main CPU completed system initialization and performed a context
+ * switch to the initialization thread. Secondary CPUs should now issue a
+ * context switch to the heir thread. This normally enables interrupts on
+ * the secondary CPU for the first time.
*/
- RTEMS_BSP_SMP_CPU_INITIALIZED = 2,
+ PER_CPU_STATE_BEGIN_MULTITASKING,
/**
- * This defines the constant used to indicate that the cpu code has
- * completed basic initialization and awaits further commands.
+ * @brief Normal multitasking state.
*/
- RTEMS_BSP_SMP_CPU_UP = 3,
+ PER_CPU_STATE_UP,
/**
- * This defines the constant used to indicate that the cpu code has
- * shut itself down.
+ * @brief This is a terminal state.
*/
- RTEMS_BSP_SMP_CPU_SHUTDOWN = 4
-} bsp_smp_cpu_state;
+ PER_CPU_STATE_SHUTDOWN
+} Per_CPU_State;
+
+#endif /* RTEMS_SMP */
/**
* @brief Per CPU Core Structure
@@ -133,15 +158,21 @@ typedef struct {
/** This element is used to lock this structure */
SMP_lock_spinlock_simple_Control lock;
- /** This indicates that the CPU is online. */
- uint32_t state;
-
/**
* This is the request for the interrupt.
*
* @note This may become a chain protected by atomic instructions.
*/
uint32_t message;
+
+ /**
+ * @brief Indicates the current state of the CPU.
+ *
+ * This field is not protected by a lock.
+ *
+ * @see _Per_CPU_Change_state() and _Per_CPU_Wait_for_state().
+ */
+ Per_CPU_State state;
#endif
} Per_CPU_Control;
#endif
@@ -218,6 +249,16 @@ void _SMP_Handler_initialize(void);
*/
void _Per_CPU_Initialize(void);
+void _Per_CPU_Change_state(
+ Per_CPU_Control *per_cpu,
+ Per_CPU_State new_state
+);
+
+void _Per_CPU_Wait_for_state(
+ const Per_CPU_Control *per_cpu,
+ Per_CPU_State desired_state
+);
+
#endif
/*
diff --git a/cpukit/score/include/rtems/score/smp.h b/cpukit/score/include/rtems/score/smp.h
index f4bf72e..c7de6d6 100644
--- a/cpukit/score/include/rtems/score/smp.h
+++ b/cpukit/score/include/rtems/score/smp.h
@@ -58,13 +58,6 @@ extern "C" {
*/
#define RTEMS_BSP_SMP_SHUTDOWN 0x04
-/**
- * This defines the bit which indicates the interprocessor interrupt
- * has been requested that the receiving CPU needs to perform a context
- * switch to the first task.
- */
-#define RTEMS_BSP_SMP_FIRST_TASK 0x08
-
#ifndef ASM
/**
* @brief Number of CPUs in a SMP system.
@@ -75,6 +68,16 @@ extern "C" {
SCORE_EXTERN uint32_t _SMP_Processor_count;
/**
+ * @brief Sends a SMP message to a processor.
+ *
+ * The target processor may be the sending processor.
+ *
+ * @param[in] cpu The target processor of the message.
+ * @param[in] message The message.
+ */
+void _SMP_Send_message( int cpu, uint32_t message );
+
+/**
* @brief Request of others CPUs.
*
* This method is invoked by RTEMS when it needs to make a request
diff --git a/cpukit/score/src/percpu.c b/cpukit/score/src/percpu.c
index f01d933..a957053 100644
--- a/cpukit/score/src/percpu.c
+++ b/cpukit/score/src/percpu.c
@@ -56,9 +56,6 @@
p->interrupt_stack_high = (void *)ptr;
}
#endif
-
- p->state = RTEMS_BSP_SMP_CPU_INITIAL_STATE;
- RTEMS_COMPILER_MEMORY_BARRIER();
}
/*
@@ -67,6 +64,32 @@
max_cpus = bsp_smp_initialize( max_cpus );
_SMP_Processor_count = max_cpus;
+
+ for ( cpu = 1 ; cpu < max_cpus; ++cpu ) {
+ _Per_CPU_Wait_for_state(
+ &_Per_CPU_Information[ cpu ],
+ PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING
+ );
+ }
+ }
+
+ void _Per_CPU_Change_state(
+ Per_CPU_Control *per_cpu,
+ Per_CPU_State new_state
+ )
+ {
+ per_cpu->state = new_state;
+ _CPU_Processor_event_broadcast();
+ }
+
+ void _Per_CPU_Wait_for_state(
+ const Per_CPU_Control *per_cpu,
+ Per_CPU_State desired_state
+ )
+ {
+ while ( per_cpu->state != desired_state ) {
+ _CPU_Processor_event_receive();
+ }
}
#else
/*
diff --git a/cpukit/score/src/smp.c b/cpukit/score/src/smp.c
index a06db5e..aee1c45 100644
--- a/cpukit/score/src/smp.c
+++ b/cpukit/score/src/smp.c
@@ -27,142 +27,87 @@
#include <rtems/bspIo.h>
#endif
-/*
- * Process request to switch to the first task on a secondary core.
- */
-void rtems_smp_run_first_task(int cpu)
+void rtems_smp_secondary_cpu_initialize( void )
{
- Thread_Control *heir;
- ISR_Level level;
+ int self = bsp_smp_processor_id();
+ Per_CPU_Control *per_cpu = &_Per_CPU_Information[ self ];
+ Thread_Control *heir;
- _ISR_Disable_on_this_core( level );
+ #if defined(RTEMS_DEBUG)
+ printk( "Made it to %d -- ", self );
+ #endif
- /*
- * The Scheduler will have selected the heir thread for each CPU core.
- * Now we have been requested to perform the first context switch. So
- * force a switch to the designated heir and make it executing on
- * THIS core.
- */
- heir = _Thread_Heir;
- _Thread_Executing = heir;
+ _Per_CPU_Change_state( per_cpu, PER_CPU_STATE_READY_TO_BEGIN_MULTITASKING );
- _CPU_Context_switch_to_first_task_smp( &heir->Registers );
-}
+ _Per_CPU_Wait_for_state( per_cpu, PER_CPU_STATE_BEGIN_MULTITASKING );
-void rtems_smp_secondary_cpu_initialize(void)
-{
- int cpu;
- ISR_Level level;
-
- cpu = bsp_smp_processor_id();
+ _Per_CPU_Change_state( per_cpu, PER_CPU_STATE_UP );
/*
- * Inform the primary CPU that this secondary CPU is initialized
- * and ready to dispatch to the first thread it is supposed to
- * execute when the primary CPU is ready.
+ * The Scheduler will have selected the heir thread for each CPU core.
+ * Now we have been requested to perform the first context switch. So
+ * force a switch to the designated heir and make it executing on
+ * THIS core.
*/
- _Per_CPU_Information[cpu].state = RTEMS_BSP_SMP_CPU_INITIALIZED;
-
- #if defined(RTEMS_DEBUG)
- printk( "Made it to %d -- ", cpu );
- #endif
+ heir = per_cpu->heir;
+ per_cpu->executing = heir;
/*
- * With this secondary core out of reset, we can wait for the
- * request to switch to the first task.
+ * Threads begin execution in the _Thread_Handler() function. This function
+ * will call _Thread_Enable_dispatch().
*/
- while(1) {
- uint32_t message;
-
- bsp_smp_wait_for(
- (volatile unsigned int *)&_Per_CPU_Information[cpu].message,
- RTEMS_BSP_SMP_FIRST_TASK,
- 10000
- );
+ _Thread_Disable_dispatch();
- level = _SMP_lock_spinlock_simple_Obtain( &_Per_CPU_Information[cpu].lock );
- message = _Per_CPU_Information[cpu].message;
- if ( message & RTEMS_BSP_SMP_FIRST_TASK ) {
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
- _ISR_Set_level( 0 );
- }
-
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
- }
+ _CPU_Context_switch_to_first_task_smp( &heir->Registers );
}
-void rtems_smp_process_interrupt(void)
+void rtems_smp_process_interrupt( void )
{
- int cpu;
- uint32_t message;
- ISR_Level level;
+ int self = bsp_smp_processor_id();
+ Per_CPU_Control *per_cpu = &_Per_CPU_Information[ self ];
+ uint32_t message;
+ ISR_Level level;
- cpu = bsp_smp_processor_id();
- level = _SMP_lock_spinlock_simple_Obtain( &_Per_CPU_Information[cpu].lock );
- message = _Per_CPU_Information[cpu].message;
+ level = _SMP_lock_spinlock_simple_Obtain( &per_cpu->lock );
+ message = per_cpu->message;
+ per_cpu->message = 0;
+ _SMP_lock_spinlock_simple_Release( &per_cpu->lock, level );
#if defined(RTEMS_DEBUG)
{
void *sp = __builtin_frame_address(0);
if ( !(message & RTEMS_BSP_SMP_SHUTDOWN) ) {
- printk( "ISR on CPU %d -- (0x%02x) (0x%p)\n", cpu, message, sp );
+ printk( "ISR on CPU %d -- (0x%02x) (0x%p)\n", self, message, sp );
if ( message & RTEMS_BSP_SMP_CONTEXT_SWITCH_NECESSARY )
printk( "context switch necessary\n" );
if ( message & RTEMS_BSP_SMP_SIGNAL_TO_SELF )
printk( "signal to self\n" );
if ( message & RTEMS_BSP_SMP_SHUTDOWN )
printk( "shutdown\n" );
- if ( message & RTEMS_BSP_SMP_FIRST_TASK )
- printk( "switch to first task\n" );
}
printk( "Dispatch level %d\n", _Thread_Dispatch_get_disable_level() );
}
#endif
- if ( message & RTEMS_BSP_SMP_FIRST_TASK ) {
- _Per_CPU_Information[cpu].isr_nest_level = 0;
- _Per_CPU_Information[cpu].message &= ~message;
- _Per_CPU_Information[cpu].state = RTEMS_BSP_SMP_CPU_UP;
-
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
-
- rtems_smp_run_first_task(cpu);
- /* does not return */
- }
-
if ( message & RTEMS_BSP_SMP_SHUTDOWN ) {
- _Per_CPU_Information[cpu].message &= ~message;
+ _ISR_Disable_on_this_core( level );
- _Per_CPU_Information[cpu].isr_nest_level = 0;
- _Per_CPU_Information[cpu].state = RTEMS_BSP_SMP_CPU_SHUTDOWN;
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
+ while ( _Thread_Dispatch_decrement_disable_level() != 0 ) {
+ /* Release completely */
+ }
- _Thread_Enable_dispatch(); /* undo ISR code */
- _ISR_Disable_on_this_core( level );
+ _Per_CPU_Change_state( per_cpu, PER_CPU_STATE_SHUTDOWN );
while(1)
;
/* does not continue past here */
}
-
- if ( message & RTEMS_BSP_SMP_CONTEXT_SWITCH_NECESSARY ) {
- #if defined(RTEMS_DEBUG)
- printk( "switch needed\n" );
- #endif
- _Per_CPU_Information[cpu].message &= ~message;
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
- }
}
-/*
- * Send an interrupt processor request to another cpu.
- */
-void _SMP_Send_message(
- int cpu,
- uint32_t message
-)
+void _SMP_Send_message( int cpu, uint32_t message )
{
+ Per_CPU_Control *per_cpu = &_Per_CPU_Information[ cpu ];
ISR_Level level;
#if defined(RTEMS_DEBUG)
@@ -170,90 +115,82 @@ void _SMP_Send_message(
printk( "Send 0x%x to %d\n", message, cpu );
#endif
- level = _SMP_lock_spinlock_simple_Obtain( &_Per_CPU_Information[cpu].lock );
- _Per_CPU_Information[cpu].message |= message;
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
+ level = _SMP_lock_spinlock_simple_Obtain( &per_cpu->lock );
+ per_cpu->message |= message;
+ _SMP_lock_spinlock_simple_Release( &per_cpu->lock, level );
+
bsp_smp_interrupt_cpu( cpu );
}
-void _SMP_Broadcast_message(
- uint32_t message
-)
+void _SMP_Broadcast_message( uint32_t message )
{
- int dest_cpu;
- int cpu;
- ISR_Level level;
-
- cpu = bsp_smp_processor_id();
+ int self = bsp_smp_processor_id();
+ int ncpus = _SMP_Processor_count;
+ int cpu;
- for ( dest_cpu=0 ; dest_cpu < _SMP_Processor_count; dest_cpu++ ) {
- if ( cpu == dest_cpu )
- continue;
- level = _SMP_lock_spinlock_simple_Obtain( &_Per_CPU_Information[cpu].lock );
- _Per_CPU_Information[dest_cpu].message |= message;
- _SMP_lock_spinlock_simple_Release( &_Per_CPU_Information[cpu].lock, level );
+ for ( cpu = 0 ; cpu < ncpus ; ++cpu ) {
+ if ( cpu != self ) {
+ Per_CPU_Control *per_cpu = &_Per_CPU_Information[ cpu ];
+ ISR_Level level = _SMP_lock_spinlock_simple_Obtain( &per_cpu->lock );
+ per_cpu->message |= message;
+ _SMP_lock_spinlock_simple_Release( &per_cpu->lock, level );
+ }
}
+
bsp_smp_broadcast_interrupt();
}
-void _SMP_Request_other_cores_to_perform_first_context_switch(void)
+void _SMP_Request_other_cores_to_perform_first_context_switch( void )
{
- int cpu;
+ int self = bsp_smp_processor_id();
+ int ncpus = _SMP_Processor_count;
+ int cpu;
- _Per_CPU_Information[cpu].state = RTEMS_BSP_SMP_CPU_UP;
- for (cpu=1 ; cpu < _SMP_Processor_count ; cpu++ ) {
- _SMP_Send_message( cpu, RTEMS_BSP_SMP_FIRST_TASK );
+ for ( cpu = 0 ; cpu < ncpus ; ++cpu ) {
+ if ( cpu != self ) {
+ _Per_CPU_Change_state(
+ &_Per_CPU_Information[ cpu ],
+ PER_CPU_STATE_BEGIN_MULTITASKING
+ );
+ }
}
}
-void _SMP_Request_other_cores_to_dispatch(void)
+void _SMP_Request_other_cores_to_dispatch( void )
{
- int i;
- int cpu;
+ if ( _System_state_Is_up( _System_state_Get() ) ) {
+ int self = bsp_smp_processor_id();
+ int ncpus = _SMP_Processor_count;
+ int cpu;
- cpu = bsp_smp_processor_id();
+ for ( cpu = 0 ; cpu < ncpus ; ++cpu ) {
+ const Per_CPU_Control *per_cpu = &_Per_CPU_Information[ cpu ];
- if ( !_System_state_Is_up (_System_state_Current) )
- return;
- for (i=1 ; i < _SMP_Processor_count ; i++ ) {
- if ( cpu == i )
- continue;
- if ( _Per_CPU_Information[i].state != RTEMS_BSP_SMP_CPU_UP )
- continue;
- if ( !_Per_CPU_Information[i].dispatch_necessary )
- continue;
- _SMP_Send_message( i, RTEMS_BSP_SMP_CONTEXT_SWITCH_NECESSARY );
+ if (
+ cpu != self
+ && per_cpu->state == PER_CPU_STATE_UP
+ && per_cpu->dispatch_necessary
+ ) {
+ _SMP_Send_message( cpu, RTEMS_BSP_SMP_CONTEXT_SWITCH_NECESSARY );
+ }
+ }
}
}
-void _SMP_Request_other_cores_to_shutdown(void)
+void _SMP_Request_other_cores_to_shutdown( void )
{
- bool allDown;
- int ncpus;
- int n;
- int cpu;
-
- cpu = bsp_smp_processor_id();
- ncpus = _SMP_Processor_count;
+ int self = bsp_smp_processor_id();
+ int ncpus = _SMP_Processor_count;
+ int cpu;
_SMP_Broadcast_message( RTEMS_BSP_SMP_SHUTDOWN );
- allDown = true;
- for (n=0 ; n<ncpus ; n++ ) {
- if ( n == cpu )
- continue;
- bsp_smp_wait_for(
- (unsigned int *)&_Per_CPU_Information[n].state,
- RTEMS_BSP_SMP_CPU_SHUTDOWN,
- 10000
- );
- if ( _Per_CPU_Information[n].state != RTEMS_BSP_SMP_CPU_SHUTDOWN )
- allDown = false;
+ for ( cpu = 0 ; cpu < ncpus ; ++cpu ) {
+ if ( cpu != self ) {
+ _Per_CPU_Wait_for_state(
+ &_Per_CPU_Information[ cpu ],
+ PER_CPU_STATE_SHUTDOWN
+ );
+ }
}
- if ( !allDown )
- printk( "not all down -- timed out\n" );
- #if defined(RTEMS_DEBUG)
- else
- printk( "All CPUs shutdown successfully\n" );
- #endif
}
--
1.7.7
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