sched: explicitly select the cpuload clock source configuration

boards/arm/imxrt/imxrt1050-evk/configs/libcxxtest/defconfig

@@ -32,7 +32,7 @@ CONFIG_NSH_LINELEN=64
 CONFIG_NSH_READLINE=y
 CONFIG_RAM_SIZE=536870912
 CONFIG_RAM_START=0x20200000
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_START_DAY=14
 CONFIG_START_MONTH=3
 CONFIG_SYSTEM_NSH=y

boards/arm/imxrt/imxrt1060-evk/configs/libcxxtest/defconfig

@@ -32,7 +32,7 @@ CONFIG_NSH_LINELEN=64
 CONFIG_NSH_READLINE=y
 CONFIG_RAM_SIZE=1048576
 CONFIG_RAM_START=0x20200000
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_START_DAY=14
 CONFIG_START_MONTH=3
 CONFIG_SYSTEM_NSH=y

boards/arm/imxrt/imxrt1064-evk/configs/libcxxtest/defconfig

@@ -32,7 +32,7 @@ CONFIG_NSH_LINELEN=64
 CONFIG_NSH_READLINE=y
 CONFIG_RAM_SIZE=1048576
 CONFIG_RAM_START=0x20200000
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_START_DAY=14
 CONFIG_START_MONTH=3
 CONFIG_SYSTEM_NSH=y

boards/arm/imxrt/teensy-4.x/configs/pikron-bb/defconfig

@@ -143,7 +143,6 @@ CONFIG_RAM_SIZE=1048576
 CONFIG_RAM_START=0x20200000
 CONFIG_READLINE_CMD_HISTORY=y
 CONFIG_RR_INTERVAL=10
-CONFIG_SCHED_CPULOAD=y
 CONFIG_SCHED_LPWORK=y
 CONFIG_SCHED_TICKLESS=y
 CONFIG_SCHED_TICKLESS_ALARM=y

boards/arm/lpc17xx_40xx/lx_cpu/configs/nsh/defconfig

@@ -138,7 +138,7 @@ CONFIG_PTHREAD_STACK_MIN=1024
 CONFIG_RAM_SIZE=65536
 CONFIG_RAM_START=0x10000000
 CONFIG_RR_INTERVAL=200
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKPRIORITY=192
 CONFIG_SCHED_IRQMONITOR=y

boards/arm/sam34/sam4s-xplained-pro/Kconfig

@@ -18,7 +18,7 @@ config SAM4S_XPLAINED_PRO_SCHED_TIMER_DEVPATH
 config SAM4S_XPLAINED_PRO_CPULOAD_TIMER_DEVPATH
 	string "CPU Load Timer Device Path"
 	default "/dev/tc0"
-	depends on TIMER && SCHED_CPULOAD && SCHED_CPULOAD_EXTCLK
+	depends on TIMER && SCHED_CPULOAD_EXTCLK
 
 config SAM34_NAND_BLOCKMOUNT
 	bool "NAND FLASH auto-mount"

boards/arm/stm32/stm32butterfly2/configs/nsh/defconfig

@@ -50,7 +50,7 @@ CONFIG_RAM_START=0x20000000
 CONFIG_RAW_BINARY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RR_INTERVAL=100
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKPRIORITY=192
 CONFIG_SCHED_HPWORKSTACKSIZE=1024

boards/arm/stm32/stm32butterfly2/configs/nshnet/defconfig

@@ -63,7 +63,7 @@ CONFIG_RAM_START=0x20000000
 CONFIG_RAW_BINARY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RR_INTERVAL=100
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKPRIORITY=192
 CONFIG_SCHED_HPWORKSTACKSIZE=1024

boards/arm/stm32/stm32butterfly2/configs/nshusbdev/defconfig

@@ -49,7 +49,7 @@ CONFIG_RAM_START=0x20000000
 CONFIG_RAW_BINARY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RR_INTERVAL=100
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKPRIORITY=192
 CONFIG_SCHED_HPWORKSTACKSIZE=1024

boards/arm/stm32/stm32butterfly2/configs/nshusbhost/defconfig

@@ -50,7 +50,7 @@ CONFIG_RAM_START=0x20000000
 CONFIG_RAW_BINARY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RR_INTERVAL=100
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKPRIORITY=192
 CONFIG_SCHED_HPWORKSTACKSIZE=1024

boards/arm/stm32h7/nucleo-h743zi2/configs/jumbo/defconfig

@@ -88,7 +88,7 @@ CONFIG_RAW_BINARY=y
 CONFIG_READLINE_CMD_HISTORY=y
 CONFIG_READLINE_TABCOMPLETION=y
 CONFIG_RR_INTERVAL=200
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_HPWORK=y
 CONFIG_SCHED_HPWORKSTACKSIZE=2048
 CONFIG_SCHED_IRQMONITOR=y

boards/risc-v/bl602/bl602evb/configs/timer/defconfig

@@ -65,7 +65,7 @@ CONFIG_RAM_SIZE=134217728
 CONFIG_RAM_START=0xc0800000
 CONFIG_RAW_BINARY=y
 CONFIG_RR_INTERVAL=200
-CONFIG_SCHED_CPULOAD=y
+CONFIG_SCHED_CPULOAD_SYSCLK=y
 CONFIG_SCHED_WAITPID=y
 CONFIG_STACK_COLORATION=y
 CONFIG_START_DAY=20

crypto/random_pool.c

@@ -213,7 +213,7 @@ static void addentropy(FAR const uint32_t *buf, size_t n, bool inc_new)
 
 static void initentropy(FAR blake2s_state *S)
 {
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   struct cpuload_s load;
 #endif
   uint32_t tmp;
@@ -231,7 +231,7 @@ static void initentropy(FAR blake2s_state *S)
 
   tmp = sizeof(entropy_pool.pool);
   tmp <<= 27;
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   clock_cpuload(0, &load);
   tmp += load.total ^ ROTL_32(load.active, 23);
 #endif

fs/procfs/Kconfig

@@ -45,7 +45,7 @@ config FS_PROCFS_EXCLUDE_CPUINFO
 
 config FS_PROCFS_EXCLUDE_CPULOAD
 	bool "Exclude CPU load"
-	depends on SCHED_CPULOAD
+	depends on !SCHED_CPULOAD_NONE
 	default DEFAULT_SMALL
 
 config FS_PROCFS_EXCLUDE_ENVIRON

fs/procfs/fs_procfs.c

@@ -106,7 +106,8 @@ static const struct procfs_entry_s g_procfs_entries[] =
   { "cpuinfo",      &g_cpuinfo_operations,  PROCFS_FILE_TYPE   },
 #endif
 
-#if defined(CONFIG_SCHED_CPULOAD) && !defined(CONFIG_FS_PROCFS_EXCLUDE_CPULOAD)
+#if !defined(CONFIG_SCHED_CPULOAD_NONE) && \
+    !defined(CONFIG_FS_PROCFS_EXCLUDE_CPULOAD)
   { "cpuload",      &g_cpuload_operations,  PROCFS_FILE_TYPE   },
 #endif
 

fs/procfs/fs_procfscpuload.c

@@ -45,7 +45,8 @@
 #include <nuttx/fs/procfs.h>
 
 #if !defined(CONFIG_DISABLE_MOUNTPOINT) && defined(CONFIG_FS_PROCFS)
-#if defined(CONFIG_SCHED_CPULOAD) && !defined(CONFIG_FS_PROCFS_EXCLUDE_CPULOAD)
+#if !defined(CONFIG_SCHED_CPULOAD_NONE) && \
+    !defined(CONFIG_FS_PROCFS_EXCLUDE_CPULOAD)
 
 /****************************************************************************
  * Pre-processor Definitions

fs/procfs/fs_procfsproc.c

@@ -54,7 +54,7 @@
 #include <nuttx/fs/ioctl.h>
 #include <nuttx/mm/mm.h>
 
-#if defined(CONFIG_SCHED_CPULOAD) || defined(CONFIG_SCHED_CRITMONITOR)
+#if !defined(CONFIG_SCHED_CPULOAD_NONE) || defined(CONFIG_SCHED_CRITMONITOR)
 #  include <nuttx/clock.h>
 #endif
 
@@ -84,7 +84,7 @@ enum proc_node_e
   PROC_LEVEL0 = 0,                    /* The top-level directory */
   PROC_STATUS,                        /* Task/thread status */
   PROC_CMDLINE,                       /* Task command line */
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   PROC_LOADAVG,                       /* Average CPU utilization */
 #endif
 #ifdef CONFIG_SCHED_CRITMONITOR
@@ -171,7 +171,7 @@ static ssize_t proc_status(FAR struct proc_file_s *procfile,
 static ssize_t proc_cmdline(FAR struct proc_file_s *procfile,
                  FAR struct tcb_s *tcb, FAR char *buffer, size_t buflen,
                  off_t offset);
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 static ssize_t proc_loadavg(FAR struct proc_file_s *procfile,
                  FAR struct tcb_s *tcb, FAR char *buffer, size_t buflen,
                  off_t offset);
@@ -278,7 +278,7 @@ static const struct proc_node_s g_cmdline =
   "cmdline",      "cmdline", (uint8_t)PROC_CMDLINE,      DTYPE_FILE        /* Task command line */
 };
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 static const struct proc_node_s g_loadavg =
 {
   "loadavg",       "loadavg", (uint8_t)PROC_LOADAVG,     DTYPE_FILE        /* Average CPU utilization */
@@ -340,7 +340,7 @@ static FAR const struct proc_node_s * const g_nodeinfo[] =
 {
   &g_status,       /* Task/thread status */
   &g_cmdline,      /* Task command line */
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   &g_loadavg,      /* Average CPU utilization */
 #endif
 #ifdef CONFIG_SCHED_CRITMONITOR
@@ -369,7 +369,7 @@ static const struct proc_node_s * const g_level0info[] =
 {
   &g_status,       /* Task/thread status */
   &g_cmdline,      /* Task command line */
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   &g_loadavg,      /* Average CPU utilization */
 #endif
 #ifdef CONFIG_SCHED_CRITMONITOR
@@ -706,7 +706,7 @@ static ssize_t proc_cmdline(FAR struct proc_file_s *procfile,
  * Name: proc_loadavg
  ****************************************************************************/
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 static ssize_t proc_loadavg(FAR struct proc_file_s *procfile,
                             FAR struct tcb_s *tcb, FAR char *buffer,
                             size_t buflen, off_t offset)
@@ -1521,7 +1521,7 @@ static ssize_t proc_read(FAR struct file *filep, FAR char *buffer,
       ret = proc_cmdline(procfile, tcb, buffer, buflen, filep->f_pos);
       break;
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
     case PROC_LOADAVG: /* Average CPU utilization */
       ret = proc_loadavg(procfile, tcb, buffer, buflen, filep->f_pos);
       break;

include/nuttx/clock.h

@@ -274,7 +274,7 @@
 
 /* This structure is used to report CPU usage for a particular thread */
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 struct cpuload_s
 {
   volatile uint32_t total;   /* Total number of clock ticks */
@@ -615,7 +615,7 @@ int clock_systime_timespec(FAR struct timespec *ts);
  *
  ****************************************************************************/
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 int clock_cpuload(int pid, FAR struct cpuload_s *cpuload);
 #endif
 

include/nuttx/sched.h

@@ -625,7 +625,7 @@ struct tcb_s
 
   /* CPU load monitoring support ********************************************/
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   uint32_t ticks;                        /* Number of ticks on this thread */
 #endif
 

sched/Kconfig

@@ -914,9 +914,9 @@ config SCHED_CRITMONITOR_MAXTIME_PANIC
 		If this option is enabled, a panic will be triggered when
 		IRQ/WQUEUE/PREEMPTION execution time exceeds SCHED_CRITMONITOR_MAXTIME_xxx
 
-config SCHED_CPULOAD
-	bool "Enable CPU load monitoring"
-	default n
+choice
+	prompt "Select CPU load clock source"
+	default SCHED_CPULOAD_NONE
 	---help---
 		If this option is selected, the timer interrupt handler will monitor
 		if the system is IDLE or busy at the time of that the timer interrupt
@@ -932,12 +932,11 @@ config SCHED_CPULOAD
 		possible unless you provide an alternative clock to drive the
 		sampling and select SCHED_CPULOAD_EXTCLK.
 
-if SCHED_CPULOAD
-
-choice
-	prompt "Select CPU load clock source"
-	default SCHED_CPULOAD_EXTCLK if SCHED_TICKLESS
-	default SCHED_CPULOAD_CRITMONITOR if SCHED_CRITMONITOR
+config SCHED_CPULOAD_NONE
+	bool "None CPU load clock source"
+	---help---
+		If this option is enabled, the system will not support CPU load
+		measurement.
 
 config SCHED_CPULOAD_SYSCLK
 	bool "Use system clock"
@@ -955,8 +954,9 @@ config SCHED_CPULOAD_SYSCLK
 		the CPU load attributed to these threads that run synchronously with
 		they system timer may be grossly in error.
 		The CPU load measurements are determined by sampling the active
-		tasks periodically at the occurrence to a timer expiration.  By
-		default, the system clock is used to do that sampling.
+		tasks periodically at the occurrence to a timer expiration.
+		If tickless is enabled, SYSCLK should not be used. Its error will be
+		very large, and using it for analysis will lead to wrong conclusions.
 
 config SCHED_CPULOAD_EXTCLK
 	bool "Use external clock"
@@ -1068,14 +1068,13 @@ endif # SCHED_CPULOAD_EXTCLK
 
 config SCHED_CPULOAD_TIMECONSTANT
 	int "CPU load time constant"
+	depends on !SCHED_CPULOAD_NONE
 	default 2
 	---help---
 		The accumulated CPU count is divided by two when the accumulated
 		tick count exceeds this time constant.  This time constant is in
 		units of seconds.
 
-endif # SCHED_CPULOAD
-
 menuconfig SCHED_INSTRUMENTATION
 	bool "System performance monitor hooks"
 	default n

sched/misc/assert.c

@@ -297,7 +297,7 @@ static void dump_task(FAR struct tcb_s *tcb, FAR void *arg)
   size_t stack_filled = 0;
   size_t stack_used;
 #endif
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
   struct cpuload_s cpuload;
   size_t fracpart = 0;
   size_t intpart = 0;
@@ -349,7 +349,7 @@ static void dump_task(FAR struct tcb_s *tcb, FAR void *arg)
 #ifdef CONFIG_STACK_COLORATION
          "   %7zu   %3zu.%1zu%%%c"
 #endif
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
          "   %3zu.%01zu%%"
 #endif
          "   %s%s\n"
@@ -375,7 +375,7 @@ static void dump_task(FAR struct tcb_s *tcb, FAR void *arg)
          , stack_filled / 10, stack_filled % 10
          , (stack_filled >= 10 * 80 ? '!' : ' ')
 #endif
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
          , intpart, fracpart
 #endif
 #if CONFIG_TASK_NAME_SIZE > 0
@@ -431,7 +431,7 @@ static void dump_tasks(void)
 #ifdef CONFIG_STACK_COLORATION
          "      USED   FILLED "
 #endif
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
          "      CPU"
 #endif
          "   COMMAND\n");
@@ -450,7 +450,7 @@ static void dump_tasks(void)
 #  ifdef CONFIG_STACK_COLORATION
          "   %7zu   %3zu.%1zu%%%c"
 #  endif
-#  ifdef CONFIG_SCHED_CPULOAD
+#  ifndef CONFIG_SCHED_CPULOAD_NONE
          "     ----"
 #  endif
          "   irq\n"

sched/sched/CMakeLists.txt

@@ -91,7 +91,7 @@ elseif(CONFIG_SCHED_RESUMESCHEDULER)
   list(APPEND SRCS sched_resumescheduler.c)
 endif()
 
-if(CONFIG_SCHED_CPULOAD)
+if(NOT CONFIG_SCHED_CPULOAD_NONE)
   list(APPEND SRCS sched_cpuload.c)
   if(CONFIG_CPULOAD_ONESHOT)
     list(APPEND SRCS sched_cpuload_oneshot.c)

sched/sched/Make.defs

@@ -68,7 +68,7 @@ else ifeq ($(CONFIG_SCHED_RESUMESCHEDULER),y)
 CSRCS += sched_resumescheduler.c
 endif
 
-ifeq ($(CONFIG_SCHED_CPULOAD),y)
+ifneq ($(CONFIG_SCHED_CPULOAD_NONE),y)
 CSRCS += sched_cpuload.c
 ifeq ($(CONFIG_CPULOAD_ONESHOT),y)
 CSRCS += sched_cpuload_oneshot.c

sched/sched/sched.h

@@ -235,7 +235,7 @@ extern volatile int g_npidhash;
 
 extern const struct tasklist_s g_tasklisttable[NUM_TASK_STATES];
 
-#ifdef CONFIG_SCHED_CPULOAD
+#ifndef CONFIG_SCHED_CPULOAD_NONE
 /* This is the total number of clock tick counts.  Essentially the
  * 'denominator' for all CPU load calculations.
  */

sched/sched/sched_cpuload.c

@@ -32,8 +32,6 @@
 
 #include "sched/sched.h"
 
-#ifdef CONFIG_SCHED_CPULOAD
-
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
@@ -227,5 +225,3 @@ int clock_cpuload(int pid, FAR struct cpuload_s *cpuload)
   leave_critical_section(flags);
   return ret;
 }
-
-#endif /* CONFIG_SCHED_CPULOAD */