[PATCH 4/4] score: _CPU_SMP_Get_current_processor()
Sebastian Huber
sebastian.huber at embedded-brains.de
Wed Feb 19 13:42:28 UTC 2014
Remove RTEMS_COMPILER_PURE_ATTRIBUTE from _SMP_Get_current_processor()
and all _CPU_SMP_Get_current_processor(). Make inline ASM statements
volatile again. Test smptests/smpmigration01 showed that GCC optimizes
too much otherwise.
---
cpukit/score/cpu/arm/rtems/score/cpu.h | 5 +-
cpukit/score/cpu/i386/rtems/score/cpu.h | 2 +-
cpukit/score/cpu/no_cpu/rtems/score/cpu.h | 3 +-
cpukit/score/cpu/powerpc/rtems/score/cpu.h | 5 +-
cpukit/score/cpu/sparc/rtems/score/cpu.h | 6 +--
cpukit/score/cpu/sparc/rtems/score/sparc.h | 2 +-
cpukit/score/include/rtems/score/smp.h | 3 +-
testsuites/smptests/smpmigration01/init.c | 50 +++++++++++++++++--
.../smptests/smpmigration01/smpmigration01.scn | 32 ++++++++-----
9 files changed, 74 insertions(+), 34 deletions(-)
diff --git a/cpukit/score/cpu/arm/rtems/score/cpu.h b/cpukit/score/cpu/arm/rtems/score/cpu.h
index a58fa9e..d0ed61f 100644
--- a/cpukit/score/cpu/arm/rtems/score/cpu.h
+++ b/cpukit/score/cpu/arm/rtems/score/cpu.h
@@ -469,13 +469,12 @@ void _CPU_Context_validate( uintptr_t pattern );
#ifdef RTEMS_SMP
uint32_t _CPU_SMP_Initialize( uint32_t configured_cpu_count );
- RTEMS_COMPILER_PURE_ATTRIBUTE static inline uint32_t
- _CPU_SMP_Get_current_processor( void )
+ static inline uint32_t _CPU_SMP_Get_current_processor( void )
{
uint32_t mpidr;
/* Use ARMv7 Multiprocessor Affinity Register (MPIDR) */
- __asm__ (
+ __asm__ volatile (
"mrc p15, 0, %[mpidr], c0, c0, 5\n"
: [mpidr] "=&r" (mpidr)
);
diff --git a/cpukit/score/cpu/i386/rtems/score/cpu.h b/cpukit/score/cpu/i386/rtems/score/cpu.h
index 3c37006..047ab69 100644
--- a/cpukit/score/cpu/i386/rtems/score/cpu.h
+++ b/cpukit/score/cpu/i386/rtems/score/cpu.h
@@ -464,7 +464,7 @@ uint32_t _CPU_ISR_Get_level( void );
#if defined(RTEMS_SMP)
uint32_t _CPU_SMP_Initialize( uint32_t configured_cpu_count );
- RTEMS_COMPILER_PURE_ATTRIBUTE uint32_t _CPU_SMP_Get_current_processor( void );
+ uint32_t _CPU_SMP_Get_current_processor( void );
void _CPU_SMP_Send_interrupt( uint32_t target_processor_index );
diff --git a/cpukit/score/cpu/no_cpu/rtems/score/cpu.h b/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
index e250639..5c34e17 100644
--- a/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
+++ b/cpukit/score/cpu/no_cpu/rtems/score/cpu.h
@@ -1486,8 +1486,7 @@ CPU_Counter_ticks _CPU_Counter_difference(
* current processor in the system. The set of processor indices is the
* range of integers starting with zero up to the processor count minus one.
*/
- RTEMS_COMPILER_PURE_ATTRIBUTE static inline uint32_t
- _CPU_SMP_Get_current_processor( void )
+ static inline uint32_t _CPU_SMP_Get_current_processor( void )
{
return 123;
}
diff --git a/cpukit/score/cpu/powerpc/rtems/score/cpu.h b/cpukit/score/cpu/powerpc/rtems/score/cpu.h
index 5e9e5f9..4e6fc74 100644
--- a/cpukit/score/cpu/powerpc/rtems/score/cpu.h
+++ b/cpukit/score/cpu/powerpc/rtems/score/cpu.h
@@ -1036,13 +1036,12 @@ void _CPU_Context_validate( uintptr_t pattern );
#ifdef RTEMS_SMP
uint32_t _CPU_SMP_Initialize( uint32_t configured_cpu_count );
- RTEMS_COMPILER_PURE_ATTRIBUTE static inline uint32_t
- _CPU_SMP_Get_current_processor( void )
+ static inline uint32_t _CPU_SMP_Get_current_processor( void )
{
uint32_t pir;
/* Use Book E Processor ID Register (PIR) */
- __asm__ (
+ __asm__ volatile (
"mfspr %[pir], 286"
: [pir] "=&r" (pir)
);
diff --git a/cpukit/score/cpu/sparc/rtems/score/cpu.h b/cpukit/score/cpu/sparc/rtems/score/cpu.h
index 19454a6..d68b0c0 100644
--- a/cpukit/score/cpu/sparc/rtems/score/cpu.h
+++ b/cpukit/score/cpu/sparc/rtems/score/cpu.h
@@ -1164,14 +1164,12 @@ void _CPU_Context_restore(
uint32_t _CPU_SMP_Initialize( uint32_t configured_cpu_count );
#if defined(__leon__)
- RTEMS_COMPILER_PURE_ATTRIBUTE static inline uint32_t
- _CPU_SMP_Get_current_processor( void )
+ static inline uint32_t _CPU_SMP_Get_current_processor( void )
{
return _LEON3_Get_current_processor();
}
#else
- RTEMS_COMPILER_PURE_ATTRIBUTE uint32_t
- _CPU_SMP_Get_current_processor( void );
+ uint32_t _CPU_SMP_Get_current_processor( void );
#endif
void _CPU_SMP_Send_interrupt( uint32_t target_processor_index );
diff --git a/cpukit/score/cpu/sparc/rtems/score/sparc.h b/cpukit/score/cpu/sparc/rtems/score/sparc.h
index 4539e7d..e52c274 100644
--- a/cpukit/score/cpu/sparc/rtems/score/sparc.h
+++ b/cpukit/score/cpu/sparc/rtems/score/sparc.h
@@ -298,7 +298,7 @@ static inline uint32_t _LEON3_Get_current_processor( void )
{
uint32_t asr17;
- __asm__ (
+ __asm__ volatile (
"rd %%asr17, %0"
: "=&r" (asr17)
);
diff --git a/cpukit/score/include/rtems/score/smp.h b/cpukit/score/include/rtems/score/smp.h
index 521cd7b..fcf2036 100644
--- a/cpukit/score/include/rtems/score/smp.h
+++ b/cpukit/score/include/rtems/score/smp.h
@@ -46,8 +46,7 @@ extern "C" {
#endif
#if defined( RTEMS_SMP )
- RTEMS_COMPILER_PURE_ATTRIBUTE static inline uint32_t
- _SMP_Get_current_processor( void )
+ static inline uint32_t _SMP_Get_current_processor( void )
{
return _CPU_SMP_Get_current_processor();
}
diff --git a/testsuites/smptests/smpmigration01/init.c b/testsuites/smptests/smpmigration01/init.c
index 1500dba..2422466 100644
--- a/testsuites/smptests/smpmigration01/init.c
+++ b/testsuites/smptests/smpmigration01/init.c
@@ -16,9 +16,11 @@
#include "config.h"
#endif
+#define TESTS_USE_PRINTF
#include "tmacros.h"
#include <stdio.h>
+#include <math.h>
#include <inttypes.h>
#define CPU_COUNT 2
@@ -102,6 +104,11 @@ static void stopper(rtems_task_argument arg)
}
}
+static uint32_t abs_delta(uint32_t a, uint32_t b)
+{
+ return a > b ? a - b : b - a;
+}
+
static void test(void)
{
test_context *ctx = &ctx_instance;
@@ -110,6 +117,8 @@ static void test(void)
rtems_id stopper_id;
uint32_t expected_tokens;
uint32_t total_delta;
+ uint64_t total_cycles;
+ uint32_t average_cycles;
sc = rtems_task_create(
rtems_build_name('S', 'T', 'O', 'P'),
@@ -144,21 +153,49 @@ static void test(void)
sc = rtems_task_start(stopper_id, stopper, 0);
rtems_test_assert(sc == RTEMS_SUCCESSFUL);
+ total_cycles = 0;
for (runner_index = 0; runner_index < RUNNER_COUNT; ++runner_index) {
- test_counters *counters = &ctx->counters[runner_index];
+ const test_counters *counters = &ctx->counters[runner_index];
+ size_t cpu;
+
+ for (cpu = 0; cpu < CPU_COUNT; ++cpu) {
+ total_cycles += counters->cycles_per_cpu[cpu].counter;
+ }
+ }
+ average_cycles = (uint32_t) (total_cycles / (RUNNER_COUNT * CPU_COUNT));
+
+ printf(
+ "total cycles %" PRIu64 "\n"
+ "average cycles %" PRIu32 "\n",
+ total_cycles,
+ average_cycles
+ );
+
+ for (runner_index = 0; runner_index < RUNNER_COUNT; ++runner_index) {
+ const test_counters *counters = &ctx->counters[runner_index];
size_t cpu;
printf("runner %" PRIuPTR "\n", runner_index);
for (cpu = 0; cpu < CPU_COUNT; ++cpu) {
+ uint32_t tokens = counters->tokens_per_cpu[cpu].counter;
+ uint32_t cycles = counters->cycles_per_cpu[cpu].counter;
+ double cycle_deviation = ((double) cycles - average_cycles)
+ / average_cycles;
+
printf(
"\tcpu %zu tokens %" PRIu32 "\n"
- "\tcpu %zu cycles %" PRIu32 "\n",
+ "\tcpu %zu cycles %" PRIu32 "\n"
+ "\tcpu %zu cycle deviation %f\n",
+ cpu,
+ tokens,
cpu,
- counters->tokens_per_cpu[cpu].counter,
+ cycles,
cpu,
- counters->cycles_per_cpu[cpu].counter
+ cycle_deviation
);
+
+ rtems_test_assert(fabs(cycle_deviation) < 0.5);
}
}
@@ -170,8 +207,7 @@ static void test(void)
for (cpu = 0; cpu < CPU_COUNT; ++cpu) {
uint32_t tokens = counters->tokens_per_cpu[cpu].counter;
- uint32_t delta = tokens > expected_tokens ?
- tokens - expected_tokens : expected_tokens - tokens;
+ uint32_t delta = abs_delta(tokens, expected_tokens);
rtems_test_assert(delta <= 1);
@@ -204,6 +240,8 @@ static void Init(rtems_task_argument arg)
#define CONFIGURE_MAXIMUM_TASKS (2 + RUNNER_COUNT)
+#define CONFIGURE_INIT_TASK_ATTRIBUTES RTEMS_FLOATING_POINT
+
#define CONFIGURE_RTEMS_INIT_TASKS_TABLE
#define CONFIGURE_INIT
diff --git a/testsuites/smptests/smpmigration01/smpmigration01.scn b/testsuites/smptests/smpmigration01/smpmigration01.scn
index b2b56ff..ba42cd4 100644
--- a/testsuites/smptests/smpmigration01/smpmigration01.scn
+++ b/testsuites/smptests/smpmigration01/smpmigration01.scn
@@ -1,17 +1,25 @@
*** TEST SMPMIGRATION 1 ***
+total cycles 94476101
+average cycles 15746016
runner 0
- cpu 0 tokens 453284
- cpu 0 cycles 14955317
- cpu 1 tokens 453283
- cpu 1 cycles 14978390
+ cpu 0 tokens 456994
+ cpu 0 cycles 16451659
+ cpu 0 cycle deviation 0.044814
+ cpu 1 tokens 456994
+ cpu 1 cycles 16895680
+ cpu 1 cycle deviation 0.073013
runner 1
- cpu 0 tokens 453283
- cpu 0 cycles 21302793
- cpu 1 tokens 453283
- cpu 1 cycles 21318817
+ cpu 0 tokens 456993
+ cpu 0 cycles 20561545
+ cpu 0 cycle deviation 0.305825
+ cpu 1 tokens 456994
+ cpu 1 cycles 20548432
+ cpu 1 cycle deviation 0.304992
runner 2
- cpu 0 tokens 453283
- cpu 0 cycles 19973312
- cpu 1 tokens 453283
- cpu 1 cycles 21315227
+ cpu 0 tokens 456994
+ cpu 0 cycles 10007206
+ cpu 0 cycle deviation -0.364461
+ cpu 1 tokens 456993
+ cpu 1 cycles 10011579
+ cpu 1 cycle deviation -0.364183
*** END OF TEST SMPMIGRATION 1 ***
--
1.7.7
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