pid_t: unify usage of special task IDs

Signed-off-by: Petro Karashchenko <petro.karashchenko@gmail.com>

arch/arm/include/cxd56xx/crashdump.h

@@ -104,7 +104,7 @@ typedef struct
   fault_flags_t flags;                  /* What is in the dump */
   uintptr_t     current_regs;           /* Used to validate the dump */
   int           lineno;                 /* __LINE__ to up_assert */
-  int           pid;                    /* Process ID */
+  pid_t         pid;                    /* Process ID */
   uint32_t      regs[XCPTCONTEXT_REGS]; /* Interrupt register save area */
   stack_t       stacks;                 /* Stack info */
 #if CONFIG_TASK_NAME_SIZE > 0

arch/arm/src/arm/arm_initialstate.c

@@ -61,7 +61,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/armv6-m/arm_initialstate.c

@@ -62,7 +62,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/armv7-a/arm_initialstate.c

@@ -61,7 +61,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/armv7-m/arm_initialstate.c

@@ -63,7 +63,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/armv7-r/arm_initialstate.c

@@ -61,7 +61,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/armv8-m/arm_initialstate.c

@@ -63,7 +63,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/arm/src/cxd56xx/cxd56_cpu1signal.c

@@ -26,6 +26,7 @@
 #include <stdlib.h>
 #include <errno.h>
 #include <sched.h>
+#include <nuttx/sched.h>
 #include <nuttx/kthread.h>
 #include <debug.h>
 
@@ -59,7 +60,7 @@ struct cxd56_sigtype_s
 
 struct cxd56cpu1_info_s
 {
-  int                    workerpid;
+  pid_t                  workerpid;
   int                    ndev;
   struct cxd56_sigtype_s sigtype[CXD56_CPU1_DATA_TYPE_MAX];
 };
@@ -70,7 +71,11 @@ struct cxd56cpu1_info_s
 
 static struct cxd56cpu1_info_s g_cpu1_info =
   {
-    0
+    INVALID_PROCESS_ID,
+    0,
+    {
+      0
+    }
   };
 
 /****************************************************************************
@@ -193,9 +198,9 @@ int cxd56_cpu1siginit(uint8_t sigtype, FAR void *data)
     }
 
   pid = kthread_create("gnss_receiver",
-                    CONFIG_CXD56CPU1_WORKER_THREAD_PRIORITY,
-                    CONFIG_CXD56CPU1_WORKER_STACKSIZE, cxd56cpu1_worker,
-                    (FAR char * const *) NULL);
+                       CONFIG_CXD56CPU1_WORKER_THREAD_PRIORITY,
+                       CONFIG_CXD56CPU1_WORKER_STACKSIZE, cxd56cpu1_worker,
+                       (FAR char * const *) NULL);
 
   if (pid < 0)
     {
@@ -221,7 +226,7 @@ err1:
 int cxd56_cpu1siguninit(uint8_t sigtype)
 {
   struct cxd56cpu1_info_s *priv = &g_cpu1_info;
-  int                      pid;
+  pid_t                    pid;
   int                      ret;
 
   if (sigtype >= CXD56_CPU1_DATA_TYPE_MAX)
@@ -249,7 +254,7 @@ int cxd56_cpu1siguninit(uint8_t sigtype)
     }
 
   pid             = priv->workerpid;
-  priv->workerpid = 0;
+  priv->workerpid = INVALID_PROCESS_ID;
 
   sched_unlock();
 

arch/arm/src/cxd56xx/cxd56_gnss.c

@@ -135,7 +135,7 @@ extern int fw_pm_sleepcpu(int cpuid, int mode);
 struct cxd56_gnss_sig_s
 {
   uint8_t                             enable;
-  int                                 pid;
+  pid_t                               pid;
   FAR struct cxd56_gnss_signal_info_s info;
 };
 
@@ -1466,7 +1466,7 @@ static int cxd56_gnss_set_signal(FAR struct file *filep, unsigned long arg)
   FAR struct cxd56_gnss_signal_setting_s *setting;
   FAR struct cxd56_gnss_sig_s            *sig;
   FAR struct cxd56_gnss_sig_s            *checksig;
-  int                                     pid;
+  pid_t                                   pid;
   int                                     i;
 
   if (!arg)

arch/arm/src/cxd56xx/cxd56_icc.c

@@ -116,7 +116,7 @@ struct iccdev_s
   /* for POSIX signal */
 
   int signo;
-  int pid;
+  pid_t pid;
   FAR void *sigdata;
 
   struct sq_queue_s recvq;

arch/arm/src/cxd56xx/cxd56_scu.c

@@ -113,7 +113,7 @@
 struct ev_notify_s
 {
   int signo;               /* Signal number */
-  int pid;                 /* Target PID */
+  pid_t pid;               /* Target PID */
   struct scuev_arg_s *arg; /* Event argument */
   struct scufifo_s *fifo;  /* Reverse reference to FIFO */
 };
@@ -121,7 +121,7 @@ struct ev_notify_s
 struct wm_notify_s
 {
   int signo;                 /* Signal number */
-  int pid;                   /* Target PID */
+  pid_t pid;                 /* Target PID */
   struct scutimestamp_s *ts; /* Event argument */
   struct scufifo_s *fifo;    /* Reverse reference to FIFO */
 };

arch/arm/src/cxd56xx/cxd56_usbdev.c

@@ -380,7 +380,7 @@ struct cxd56_usbdev_s
   /* signal */
 
   int signo;
-  int pid;
+  pid_t pid;
 };
 
 /* For maintaining tables of endpoint info */

arch/arm/src/rtl8720c/amebaz_depend.c

@@ -661,7 +661,7 @@ int rtw_create_task(struct task_struct *task, const char *name,
       return pid;
     }
 
-  wrap->pid = pid;
+  wrap->pid = (pid_t)pid;
   return 1;
 }
 

arch/arm/src/rtl8720c/amebaz_depend.h

@@ -66,7 +66,7 @@ struct task_struct
 };
 struct nthread_wrapper
 {
-  int pid;
+  pid_t               pid;
   thread_func_t       func;
   void                *thctx;
 };

arch/arm/src/tiva/common/tiva_can.c

@@ -141,7 +141,7 @@ struct tiva_canmod_s
 
   /* kthread message handler thread ID */
 
-  int       kthd_id;
+  pid_t     kthd_id;
 
 #ifdef CONFIG_CAN_ERRORS
   /* Asynchronously report errors when status interrupts are disabled */
@@ -438,7 +438,7 @@ static int tivacan_setup(FAR struct can_dev_s *dev)
     }
   else
     {
-      canmod->kthd_id = ret;
+      canmod->kthd_id = (pid_t)ret;
     }
 
 #ifdef CONFIG_CAN_EXTID

arch/avr/src/avr/up_initialstate.c

@@ -58,7 +58,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/avr/src/avr32/up_initialstate.c

@@ -55,7 +55,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/ceva/src/common/up_assert.c

@@ -296,7 +296,7 @@ static void _up_assert(int errorcode)
 
   /* Are we in an interrupt handler or the idle task? */
 
-  if (CURRENT_REGS || running_task()->pid == 0)
+  if (up_interrupt_context() || sched_idletask())
     {
       up_irq_save();
       for (; ; )

arch/ceva/src/xc5/up_initialstate.c

@@ -55,7 +55,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = g_idle_basestack;
       tcb->stack_base_ptr  = tcb->stack_alloc_ptr;

arch/ceva/src/xm6/up_initialstate.c

@@ -61,7 +61,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = g_idle_basestack;
       tcb->stack_base_ptr  = tcb->stack_alloc_ptr;

arch/hc/src/m9s12/m9s12_initialstate.c

@@ -56,7 +56,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/mips/src/mips32/mips_initialstate.c

@@ -59,7 +59,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/misoc/src/lm32/lm32_initialstate.c

@@ -57,7 +57,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/misoc/src/minerva/minerva_initialstate.c

@@ -61,7 +61,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/or1k/src/common/up_initialstate.c

@@ -74,7 +74,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/renesas/src/m16c/m16c_initialstate.c

@@ -57,7 +57,7 @@ void up_initial_state(FAR struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/renesas/src/rx65n/rx65n_initialstate.c

@@ -62,7 +62,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/renesas/src/sh1/sh1_initialstate.c

@@ -74,7 +74,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/risc-v/src/bl602/bl602_os_hal.c

@@ -340,9 +340,9 @@ int bl_os_task_create(const char *name,
 
 void bl_os_task_delete(void *task_handle)
 {
-  pid_t task = (int)task_handle;
+  pid_t pid = (pid_t)((uintptr_t)task_handle);
 
-  task_delete((pid_t)task);
+  task_delete(pid);
 }
 
 /****************************************************************************
@@ -358,7 +358,9 @@ void bl_os_task_delete(void *task_handle)
 
 void *bl_os_task_get_current_task(void)
 {
-  return (void *)0;
+  pid_t pid = getpid();
+
+  return (void *)((uintptr_t)pid);
 }
 
 /****************************************************************************

arch/risc-v/src/common/riscv_initialstate.c

@@ -57,7 +57,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/risc-v/src/esp32c3/esp32c3_ble_adapter.c

@@ -553,7 +553,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
       wlerr("Failed to create task\n");
     }
 
-  return pid > 0 ? true : false;
+  return pid > 0;
 }
 
 /****************************************************************************

arch/risc-v/src/esp32c3/esp32c3_rt_timer.c

@@ -68,7 +68,7 @@
 
 struct esp32c3_rt_priv_s
 {
-  int pid;
+  pid_t pid;
   sem_t toutsem;
   struct list_node runlist;
   struct list_node toutlist;
@@ -81,7 +81,7 @@ struct esp32c3_rt_priv_s
 
 static struct esp32c3_rt_priv_s g_rt_priv =
 {
-  .pid = -EINVAL,
+  .pid = INVALID_PROCESS_ID,
 };
 
 /****************************************************************************
@@ -736,7 +736,7 @@ int esp32c3_rt_timer_init(void)
   list_initialize(&priv->runlist);
   list_initialize(&priv->toutlist);
 
-  priv->pid = pid;
+  priv->pid = (pid_t)pid;
 
   flags = enter_critical_section();
 
@@ -789,10 +789,10 @@ void esp32c3_rt_timer_deinit(void)
 
   leave_critical_section(flags);
 
-  if (priv->pid != -EINVAL)
+  if (priv->pid != INVALID_PROCESS_ID)
     {
       kthread_delete(priv->pid);
-      priv->pid = -EINVAL;
+      priv->pid = INVALID_PROCESS_ID;
     }
 
   nxsem_destroy(&priv->toutsem);

arch/risc-v/src/esp32c3/esp32c3_wifi_adapter.c

@@ -1997,7 +1997,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
       wlerr("ERROR: Failed to create task\n");
     }
 
-  return pid > 0 ? true : false;
+  return pid > 0;
 }
 
 /****************************************************************************

arch/sim/src/sim/up_initialstate.c

@@ -54,7 +54,7 @@
 
 void up_initial_state(struct tcb_s *tcb)
 {
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(up_getsp() -
                                       CONFIG_IDLETHREAD_STACKSIZE -

arch/sparc/src/sparc_v8/up_dumpstate.c

@@ -108,7 +108,7 @@ void up_dumpstate(void)
 
   /* Get the limits on the user stack memory */
 
-  if (rtcb->pid == 0) /* Check for CPU0 IDLE thread */
+  if (rtcb->pid == IDLE_PROCESS_ID) /* Check for CPU0 IDLE thread */
     {
       ustackbase = g_idle_topstack - 4;
       ustacksize = CONFIG_IDLETHREAD_STACKSIZE;

arch/sparc/src/sparc_v8/up_initialstate.c

@@ -68,7 +68,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = (void *)(g_idle_topstack -
                                       CONFIG_IDLETHREAD_STACKSIZE);

arch/x86/src/i486/up_initialstate.c

@@ -55,7 +55,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/x86_64/src/intel64/up_initialstate.c

@@ -56,7 +56,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)(g_idle_topstack -
                                  CONFIG_IDLETHREAD_STACKSIZE);

arch/xtensa/src/common/xtensa_initialstate.c

@@ -60,7 +60,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       tcb->stack_alloc_ptr = g_idlestack;
       tcb->stack_base_ptr  = tcb->stack_alloc_ptr;

arch/xtensa/src/esp32/esp32_ble_adapter.c

@@ -802,7 +802,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
       wlerr("Failed to create task, error %d\n", pid);
     }
 
-  return pid > 0 ? true : false;
+  return pid > 0;
 }
 
 /****************************************************************************

arch/xtensa/src/esp32/esp32_rt_timer.c

@@ -66,7 +66,7 @@
 
 struct esp32_rt_priv_s
 {
-  int pid;
+  pid_t pid;
 
   sem_t toutsem;
 
@@ -81,7 +81,10 @@ struct esp32_rt_priv_s
  * Private Data
  ****************************************************************************/
 
-static struct esp32_rt_priv_s g_rt_priv;
+static struct esp32_rt_priv_s g_rt_priv =
+{
+  .pid = INVALID_PROCESS_ID
+};
 
 /****************************************************************************
  * Private Function Prototypes
@@ -705,7 +708,7 @@ int esp32_rt_timer_init(void)
   list_initialize(&priv->toutlist);
 
   priv->timer = tim;
-  priv->pid   = pid;
+  priv->pid   = (pid_t)pid;
 
   flags = spin_lock_irqsave(&priv->lock);
 
@@ -757,7 +760,12 @@ void esp32_rt_timer_deinit(void)
 
   spin_unlock_irqrestore(&priv->lock, flags);
 
-  kthread_delete(priv->pid);
+  if (priv->pid != INVALID_PROCESS_ID)
+    {
+      kthread_delete(priv->pid);
+      priv->pid = INVALID_PROCESS_ID;
+    }
+
   nxsem_destroy(&priv->toutsem);
 }
 

arch/xtensa/src/esp32/esp32_wifi_adapter.c

@@ -1933,7 +1933,7 @@ static int32_t esp_task_create_pinned_to_core(void *entry,
       wlerr("Failed to create task\n");
     }
 
-  return pid > 0 ? true : false;
+  return pid > 0;
 }
 
 /****************************************************************************

arch/xtensa/src/esp32s2/esp32s2_rt_timer.c

@@ -74,7 +74,7 @@
 
 struct esp32s2_rt_priv_s
 {
-  int pid;
+  pid_t pid;
   sem_t toutsem;
   struct list_node runlist;
   struct list_node toutlist;
@@ -87,7 +87,7 @@ struct esp32s2_rt_priv_s
 
 static struct esp32s2_rt_priv_s g_rt_priv =
 {
-  .pid = -EINVAL,
+  .pid = INVALID_PROCESS_ID,
 };
 
 /****************************************************************************
@@ -752,7 +752,7 @@ int esp32s2_rt_timer_init(void)
   list_initialize(&priv->runlist);
   list_initialize(&priv->toutlist);
 
-  priv->pid = pid;
+  priv->pid = (pid_t)pid;
   priv->timer = tim;
 
   flags = enter_critical_section();
@@ -832,10 +832,10 @@ void esp32s2_rt_timer_deinit(void)
 
   leave_critical_section(flags);
 
-  if (priv->pid != -EINVAL)
+  if (priv->pid != INVALID_PROCESS_ID)
     {
       kthread_delete(priv->pid);
-      priv->pid = -EINVAL;
+      priv->pid = INVALID_PROCESS_ID;
     }
 
   nxsem_destroy(&priv->toutsem);

arch/xtensa/src/esp32s3/esp32s3_rt_timer.c

@@ -72,7 +72,7 @@ static_assert(RT_TIMER_TASK_PRIORITY < CONFIG_SCHED_HPWORKPRIORITY,
 
 struct esp32s3_rt_priv_s
 {
-  int pid;                    /* PID of RT Timer kernel thread */
+  pid_t pid;                  /* PID of RT Timer kernel thread */
   int cpuint;                 /* CPU interrupt assigned to this timer */
   int core;                   /* Core that is taking care of the timer
                                * interrupts
@@ -91,7 +91,7 @@ struct esp32s3_rt_priv_s
 
 static struct esp32s3_rt_priv_s g_rt_priv =
 {
-  .pid    = -EINVAL,
+  .pid    = INVALID_PROCESS_ID,
   .cpuint = -ENOMEM,
   .core   = -ENODEV
 };
@@ -961,7 +961,7 @@ int esp32s3_rt_timer_init(void)
   list_initialize(&priv->runlist);
   list_initialize(&priv->toutlist);
 
-  priv->pid = pid;
+  priv->pid = (pid_t)pid;
 
   flags = spin_lock_irqsave(&priv->lock);
 
@@ -1044,10 +1044,10 @@ void esp32s3_rt_timer_deinit(void)
 
   spin_unlock_irqrestore(&priv->lock, flags);
 
-  if (priv->pid != -EINVAL)
+  if (priv->pid != INVALID_PROCESS_ID)
     {
       kthread_delete(priv->pid);
-      priv->pid = -EINVAL;
+      priv->pid = INVALID_PROCESS_ID;
     }
 
   nxsem_destroy(&priv->toutsem);

arch/z80/src/z180/z180_initialstate.c

@@ -54,7 +54,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)CONFIG_STACK_BASE;
 #ifdef CONFIG_STACK_COLORATION

arch/z80/src/z80/z80_initialstate.c

@@ -54,7 +54,7 @@ void up_initial_state(struct tcb_s *tcb)
 
   /* Initialize the idle thread stack */
 
-  if (tcb->pid == 0)
+  if (tcb->pid == IDLE_PROCESS_ID)
     {
       char *stack_ptr = (char *)CONFIG_STACK_BASE;
 #ifdef CONFIG_STACK_COLORATION

boards/arm/imxrt/imxrt1020-evk/src/imxrt_usbhost.c

@@ -131,7 +131,6 @@ static int ehci_waiter(int argc, char *argv[])
 
 int imxrt_usbhost_initialize(void)
 {
-  pid_t pid;
   int ret;
 
   imxrt_clockall_usboh3();
@@ -205,10 +204,10 @@ int imxrt_usbhost_initialize(void)
 
   /* Start a thread to handle device connection. */
 
-  pid = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
+  ret = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
                        CONFIG_USBHOST_STACKSIZE,
                        (main_t)ehci_waiter, (FAR char * const *)NULL);
-  if (pid < 0)
+  if (ret < 0)
     {
       uerr("ERROR: Failed to create ehci_waiter task: %d\n", ret);
       return -ENODEV;

boards/arm/imxrt/imxrt1060-evk/src/imxrt_usbhost.c

@@ -131,7 +131,6 @@ static int ehci_waiter(int argc, char *argv[])
 
 int imxrt_usbhost_initialize(void)
 {
-  pid_t pid;
   int ret;
 
   imxrt_clockall_usboh3();
@@ -203,10 +202,10 @@ int imxrt_usbhost_initialize(void)
 
   /* Start a thread to handle device connection. */
 
-  pid = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
+  ret = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
                        CONFIG_USBHOST_STACKSIZE,
                        (main_t)ehci_waiter, (FAR char * const *)NULL);
-  if (pid < 0)
+  if (ret < 0)
     {
       uerr("ERROR: Failed to create ehci_waiter task: %d\n", ret);
       return -ENODEV;

boards/arm/imxrt/imxrt1064-evk/src/imxrt_usbhost.c

@@ -131,7 +131,6 @@ static int ehci_waiter(int argc, char *argv[])
 
 int imxrt_usbhost_initialize(void)
 {
-  pid_t pid;
   int ret;
 
   imxrt_clockall_usboh3();
@@ -203,10 +202,10 @@ int imxrt_usbhost_initialize(void)
 
   /* Start a thread to handle device connection. */
 
-  pid = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
+  ret = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
                        CONFIG_USBHOST_STACKSIZE,
                        (main_t)ehci_waiter, (FAR char * const *)NULL);
-  if (pid < 0)
+  if (ret < 0)
     {
       uerr("ERROR: Failed to create ehci_waiter task: %d\n", ret);
       return -ENODEV;

boards/arm/kinetis/freedom-k28f/src/k28_usbhshost.c

@@ -398,7 +398,6 @@ static void usb_msc_disconnect(FAR void *arg)
 
 int k28_usbhost_initialize(void)
 {
-  pid_t    pid;
   int      ret;
 #  ifdef HAVE_USB_AUTOMOUNTER
   int      index;
@@ -479,10 +478,10 @@ int k28_usbhost_initialize(void)
 
   /* Start a thread to handle device connection. */
 
-  pid = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
+  ret = kthread_create("EHCI Monitor", CONFIG_USBHOST_DEFPRIO,
                        CONFIG_USBHOST_STACKSIZE,
                        (main_t)ehci_waiter, (FAR char * const *)NULL);
-  if (pid < 0)
+  if (ret < 0)
     {
       uerr("ERROR: Failed to create ehci_waiter task: %d\n", ret);
       return -ENODEV;