Add optional tracing to sleep manager lock/unlock

Add tracing output to console to track when drivers lock and unlock deep
sleep. Tracing output is enabled by configuring the
'SLEEP_PROFILING_ENABLED' at compile time.

- Wrapped sleep_manager_lock/sleep_manager_unlock in a macro to
conditionally call tracing functions when 'SLEEP_PROFILING_ENABLED' is
set.
- Define a global structure to track driver names and how many locks
they hold in the sleep manager.

Author: Steven Cartmell

hal/mbed_sleep_manager.c

@@ -14,18 +14,123 @@
  * limitations under the License.
  */
 
+#include "mbed_assert.h"
 #include "mbed_power_mgmt.h"
 #include "mbed_critical.h"
 #include "sleep_api.h"
 #include "mbed_error.h"
 #include <limits.h>
+#include <stdio.h>
 
 #if DEVICE_SLEEP
 
 // deep sleep locking counter. A target is allowed to deep sleep if counter == 0
 static uint16_t deep_sleep_lock = 0U;
 
-void sleep_manager_lock_deep_sleep(void)
+#ifdef SLEEP_PROFILING_ENABLED
+
+// Length of the identifier extracted from the driver name to store for logging.
+#define IDENTIFIER_WIDTH 7
+// Number of drivers that can be stored in the structure
+#define STATISTIC_COUNT  10
+
+typedef struct __PACKED sleep_statistic {
+    char identifier[IDENTIFIER_WIDTH];
+    uint8_t count;
+} sleep_statistic_t;
+
+static sleep_statistic_t sleep_stats[STATISTIC_COUNT];
+
+static const char* strip_path(const char* const filename)
+{
+    char *output = strrchr(filename, '/');
+
+    if (output != NULL) {
+        return output + 1;
+    }
+
+    output = strrchr(filename, '\\');
+
+    if (output != NULL) {
+        return output + 1;
+    }
+
+    return filename;
+}
+
+static size_t sleep_tracker_find_index(const char *const filename)
+{
+    char temp[IDENTIFIER_WIDTH];
+    strncpy(temp, filename, IDENTIFIER_WIDTH);
+    temp[IDENTIFIER_WIDTH - 1] = '\0';
+
+    // Search for the a driver matching the current name and return it's index
+    for (int i = 0; i < STATISTIC_COUNT; ++i) {
+        if (strcmp(sleep_stats[i].identifier, temp) == 0) {
+            return i;
+        }
+    }
+
+    // If no driver was found currently in the structure, find the first array
+    // index that hasn't been used by a driver and fill it, then return the
+    // index.
+    for (int i = 0; i < STATISTIC_COUNT; ++i) {
+        if (sleep_stats[i].identifier[0] == '\0') {
+            core_util_critical_section_enter();
+            strncpy(sleep_stats[i].identifier, temp, sizeof(temp));
+            core_util_critical_section_exit();
+
+            return i;
+        }
+    }
+
+    // Panic if there are no free indexes left to track with
+    MBED_ASSERT(true);
+
+    return -1;
+}
+
+static void sleep_tracker_print_stats(void)
+{
+    for (int i = 0; i < STATISTIC_COUNT; ++i) {
+        if (sleep_stats[i].count == 0) {
+            continue;
+        }
+
+        if (sleep_stats[i].identifier[0] == '\0') {
+            return;
+        }
+
+        printf("[id: %s, count: %u]\r\n", sleep_stats[i].identifier,
+                                          sleep_stats[i].count);
+    }
+}
+
+void sleep_tracker_lock(const char* const filename, int line)
+{
+    const char* const stripped_path = strip_path(filename);
+    size_t index = sleep_tracker_find_index(stripped_path);
+
+    core_util_atomic_incr_u8(&sleep_stats[index].count, 1);
+
+    printf("LOCK: %s, ln: %i, lock count: %u\r\n", stripped_path, line, deep_sleep_lock);
+}
+
+void sleep_tracker_unlock(const char* const filename, int line)
+{
+    const char* const stripped_path = strip_path(filename);
+    size_t index = sleep_tracker_find_index(stripped_path);
+
+    core_util_atomic_decr_u8(&sleep_stats[index].count, 1);
+
+    printf("UNLOCK: %s, ln: %i, lock count: %u\r\n", stripped_path, line, deep_sleep_lock);
+    sleep_tracker_print_stats();
+    printf("\r\n");
+}
+
+#endif // SLEEP_PROFILING_ENABLED
+
+void sleep_manager_lock_deep_sleep_internal(void)
 {
     core_util_critical_section_enter();
     if (deep_sleep_lock == USHRT_MAX) {
@@ -36,7 +141,7 @@ void sleep_manager_lock_deep_sleep(void)
     core_util_critical_section_exit();
 }
 
-void sleep_manager_unlock_deep_sleep(void)
+void sleep_manager_unlock_deep_sleep_internal(void)
 {
     core_util_critical_section_enter();
     if (deep_sleep_lock == 0) {
@@ -73,12 +178,12 @@ void sleep_manager_sleep_auto(void)
 // locking is valid only if DEVICE_SLEEP is defined
 // we provide empty implementation
 
-void sleep_manager_lock_deep_sleep(void)
+void sleep_manager_lock_deep_sleep_internal(void)
 {
 
 }
 
-void sleep_manager_unlock_deep_sleep(void)
+void sleep_manager_unlock_deep_sleep_internal(void)
 {
 
 }

platform/mbed_power_mgmt.h

@@ -23,7 +23,7 @@
 #ifndef MBED_POWER_MGMT_H
 #define MBED_POWER_MGMT_H
 
-#include "hal/sleep_api.h"
+#include "sleep_api.h"
 #include "mbed_toolchain.h"
 #include <stdbool.h>
 
@@ -63,6 +63,34 @@ extern "C" {
  * }
  * @endcode
  */
+#ifdef SLEEP_PROFILING_ENABLED
+
+#define sleep_manager_lock_deep_sleep()           \
+    do                                            \
+    {                                             \
+        sleep_manager_lock_deep_sleep_internal(); \
+        sleep_tracker_lock(__FILE__, __LINE__);   \
+    } while (0);
+
+#define sleep_manager_unlock_deep_sleep()           \
+    do                                              \
+    {                                               \
+        sleep_manager_unlock_deep_sleep_internal(); \
+        sleep_tracker_unlock(__FILE__, __LINE__);   \
+    } while (0);
+
+void sleep_tracker_lock(const char *const filename, int line);
+void sleep_tracker_unlock(const char *const filename, int line);
+
+#else
+
+#define sleep_manager_lock_deep_sleep() \
+    sleep_manager_lock_deep_sleep_internal()
+
+#define sleep_manager_unlock_deep_sleep() \
+    sleep_manager_lock_deep_sleep_internal()
+
+#endif // SLEEP_PROFILING_ENABLED
 
 /** Lock the deep sleep mode
  *
@@ -76,7 +104,7 @@ extern "C" {
  * The lock is a counter, can be locked up to USHRT_MAX
  * This function is IRQ and thread safe
  */
-void sleep_manager_lock_deep_sleep(void);
+void sleep_manager_lock_deep_sleep_internal(void);
 
 /** Unlock the deep sleep mode
  *
@@ -85,96 +113,13 @@ void sleep_manager_lock_deep_sleep(void);
  * The lock is a counter, should be equally unlocked as locked
  * This function is IRQ and thread safe
  */
-void sleep_manager_unlock_deep_sleep(void);
+void sleep_manager_unlock_deep_sleep_internal(void);
 
 /** Get the status of deep sleep allowance for a target
  *
  * @return true if a target can go to deepsleep, false otherwise
  */
 bool sleep_manager_can_deep_sleep(void);
-
-/** Enter auto selected sleep mode. It chooses the sleep or deeepsleep modes based
- *  on the deepsleep locking counter
- *
- * This function is IRQ and thread safe
- *
- * @note
- * If MBED_DEBUG is defined, only hal_sleep is allowed. This ensures the debugger
- * to be active for debug modes.
- *
- */
-void sleep_manager_sleep_auto(void);
-
-/** Send the microcontroller to sleep
- *
- * @note This function can be a noop if not implemented by the platform.
- * @note This function will be a noop in debug mode (debug build profile when MBED_DEBUG is defined).
- * @note This function will be a noop while uVisor is in use.
- * @note This function will be a noop if the following conditions are met:
- *   - The RTOS is present
- *   - The processor turn off the Systick clock during sleep
- *   - The target does not implement tickless mode
- *
- * The processor is setup ready for sleep, and sent to sleep using __WFI(). In this mode, the
- * system clock to the core is stopped until a reset or an interrupt occurs. This eliminates
- * dynamic power used by the processor, memory systems and buses. The processor, peripheral and
- * memory state are maintained, and the peripherals continue to work and can generate interrupts.
- *
- * The processor can be woken up by any internal peripheral interrupt or external pin interrupt.
- *
- * @note
- *  The mbed interface semihosting is disconnected as part of going to sleep, and can not be restored.
- * Flash re-programming and the USB serial port will remain active, but the mbed program will no longer be
- * able to access the LocalFileSystem
- */
-static inline void sleep(void)
-{
-#if !(defined(FEATURE_UVISOR) && defined(TARGET_UVISOR_SUPPORTED))
-#if DEVICE_SLEEP
-#if (MBED_CONF_RTOS_PRESENT == 0) || (DEVICE_STCLK_OFF_DURING_SLEEP == 0) || defined(MBED_TICKLESS)
-    sleep_manager_sleep_auto();
-#endif /* (MBED_CONF_RTOS_PRESENT == 0) || (DEVICE_STCLK_OFF_DURING_SLEEP == 0) || defined(MBED_TICKLESS) */
-#endif /* DEVICE_SLEEP */
-#endif /* !(defined(FEATURE_UVISOR) && defined(TARGET_UVISOR_SUPPORTED)) */
-}
-
-/** Send the microcontroller to deep sleep
- *
- * @note This function can be a noop if not implemented by the platform.
- * @note This function will be a noop in debug mode (debug build profile when MBED_DEBUG is defined)
- * @note This function will be a noop while uVisor is in use.
- *
- * This processor is setup ready for deep sleep, and sent to sleep. This mode
- * has the same sleep features as sleep plus it powers down peripherals and clocks. All state
- * is still maintained.
- *
- * The processor can only be woken up by an external interrupt on a pin or a watchdog timer.
- *
- * @note
- *  The mbed interface semihosting is disconnected as part of going to sleep, and can not be restored.
- * Flash re-programming and the USB serial port will remain active, but the mbed program will no longer be
- * able to access the LocalFileSystem
- */
-
-MBED_DEPRECATED_SINCE("mbed-os-5.6", "One entry point for an application, use sleep()")
-static inline void deepsleep(void)
-{
-#if !(defined(FEATURE_UVISOR) && defined(TARGET_UVISOR_SUPPORTED))
-#if DEVICE_SLEEP
-    sleep_manager_sleep_auto();
-#endif /* DEVICE_SLEEP */
-#endif /* !(defined(FEATURE_UVISOR) && defined(TARGET_UVISOR_SUPPORTED)) */
-}
-
-/** Resets the processor and most of the sub-system
- *
- * @note Does not affect the debug sub-system
- */
-static inline void system_reset(void)
-{
-    NVIC_SystemReset();
-}
-
 #ifdef __cplusplus
 }
 #endif