diff options
Diffstat (limited to 'nuttx/sched/Kconfig')
| -rw-r--r-- | nuttx/sched/Kconfig | 188 |
1 files changed, 160 insertions, 28 deletions
diff --git a/nuttx/sched/Kconfig b/nuttx/sched/Kconfig index bfaec3b5d..fe9a88085 100644 --- a/nuttx/sched/Kconfig +++ b/nuttx/sched/Kconfig @@ -4,7 +4,7 @@ # config MSEC_PER_TICK - int "tick timer" + int "Milliseconds per system timer tick" default 10 ---help--- The default system timer is 100Hz or MSEC_PER_TICK=10. This setting @@ -12,7 +12,7 @@ config MSEC_PER_TICK system timer interrupts at some interrupt interval other than 10 msec. config RR_INTERVAL - int "round robin timeslice" + int "Round robin timeslice (MSEC)" default 0 ---help--- The round robin timeslice will be set this number of milliseconds; @@ -38,6 +38,92 @@ config TASK_NAME_SIZE Useful if scheduler instrumentation is selected. Set to zero to disable. +config SCHED_HAVE_PARENT + bool "Support parent/child task relationships" + default n + ---help--- + Remember the ID of the parent task when a new child task is + created. This support enables some additional features (such as + SIGCHLD) and modifies the behavior of other interfaces. For + example, it makes waitpid() more standards complete by restricting + the waited-for tasks to the children of the caller. Default: + disabled. + +config SCHED_CHILD_STATUS + bool "Retain child exit status" + default n + depends on SCHED_HAVE_PARENT + ---help--- + If this option is selected, then the exit status of the child task + will be retained after the child task exits. This option should be + selected if you require knowledge of a child process' exit status. + Without this setting, wait(), waitpid() or waitid() may fail. For + example, if you do: + + 1) Start child task + 2) Wait for exit status (using wait(), waitpid(), or waitid()). + + This can fail because the child task may run to completion before + the wait begins. There is a non-standard work-around in this case: + The above sequence will work if you disable pre-emption using + sched_lock() prior to starting the child task, then re-enable pre- + emption with sched_unlock() after the wait completes. This works + because the child task is not permitted to run until the wait is in + place. + + The standard solution would be to enable SCHED_CHILD_STATUS. In + this case the exit status of the child task is retained after the + child exits and the wait will successful obtain the child task's + exit status whether it is called before the child task exits or not. + + Warning: If you enable this feature, then your application must + either (1) take responsibility for reaping the child status with wait(), + waitpid(), or waitid(), or (2) suppress retention of child status. + If you do not reap the child status, then you have a memory leak and + your system will eventually fail. + + Retention of child status can be suppressed on the parent using logic like: + + struct sigaction sa; + + sa.sa_handler = SIG_IGN; + sa.sa_flags = SA_NOCLDWAIT; + int ret = sigaction(SIGCHLD, &sa, NULL); + +config PREALLOC_CHILDSTATUS + int "Number of pre-allocated child status" + default 0 + depends on SCHED_CHILD_STATUS + ---help--- + To prevent runaway child status allocations and to improve + allocation performance, child task exit status structures are pre- + allocated when the system boots. This setting determines the number + of child status structures that will be pre-allocated. If this + setting is not defined or if it is defined to be zero then a value + of 2*MAX_TASKS is used. + + Note that there cannot be more that CONFIG_MAX_TASKS tasks in total. + However, the number of child status structures may need to be + significantly larger because this number includes the maximum number + of tasks that are running PLUS the number of tasks that have exit'ed + without having their exit status reaped (via wait(), waitid(), or + waitpid()). + + Obviously, if tasks spawn children indefinitely and never have the + exit status reaped, then you may have a memory leak! If you enable + the SCHED_CHILD_STATUS feature, then your application must take + responsibility for either (1) reaping the child status with wait(), + waitpid(), or waitid() or it must (2) suppress retention of child + status. Otherwise, your system will eventually fail. + + Retention of child status can be suppressed on the parent using logic like: + + struct sigaction sa; + + sa.sa_handler = SIG_IGN; + sa.sa_flags = SA_NOCLDWAIT; + int ret = sigaction(SIGCHLD, &sa, NULL); + config JULIAN_TIME bool "Enables Julian time conversions" default n @@ -45,15 +131,15 @@ config JULIAN_TIME Enables Julian time conversions config START_YEAR - int "start year" + int "Start year" default 2013 config START_MONTH - int "start month" + int "Start month" default 1 config START_DAY - int "start day" + int "Start day" default 1 config DEV_CONSOLE @@ -77,7 +163,7 @@ config PRIORITY_INHERITANCE Set to enable support for priority inheritance on mutexes and semaphores. config SEM_PREALLOCHOLDERS - int "Pre-allocated holders" + int "Number of pre-allocated holders" default 16 depends on PRIORITY_INHERITANCE ---help--- @@ -127,6 +213,7 @@ config SDCLONE_DISABLE config SCHED_WORKQUEUE bool "Enable worker thread" default n + depends on !DISABLE_SIGNALS ---help--- Create a dedicated "worker" thread to handle delayed processing from interrupt handlers. This feature is required for some drivers but, if there are no @@ -158,14 +245,6 @@ config SCHED_WORKSTACKSIZE ---help--- The stack size allocated for the worker thread. Default: 2K. -config SIG_SIGWORK - int "Worker thread wakeup signal" - default 4 - depends on SCHED_WORKQUEUE - ---help--- - The signal number that will be used to wake-up the worker thread. - Default: 4 - config SCHED_LPWORK bool "Enable a lower priority worker thread" default n @@ -203,7 +282,12 @@ config SCHED_WAITPID bool "Enable waitpid() API" default n ---help--- - Enables the waitpid() API + Enables the waitpid() interface in a default, non-standard mode + (non-standard in the sense that the waited for PID need not be child + of the caller). If SCHED_HAVE_PARENT is also defined, then this + setting will modify the behavior or waitpid() (making more spec + compliant) and will enable the waitid() and wait() interfaces as + well. config SCHED_ATEXIT bool "Enable atexit() API" @@ -310,10 +394,60 @@ config DISABLE_POLL depends on DISABLE_OS_API default n +if !DISABLE_SIGNALS +comment "Signal Numbers" + +config SIG_SIGUSR1 + int "SIGUSR1" + default 1 + ---help--- + Value of standard user signal 1 (SIGUSR1). Default: 1 + +config SIG_SIGUSR2 + int "SIGUSR2" + default 2 + ---help--- + Value of standard user signal 2 (SIGUSR2). Default: 2 + +config SIG_SIGALARM + int "SIGALRM" + default 3 + ---help--- + Default the signal number used with POSIX timers (SIGALRM). + Default: 3 + +config SIG_SIGCHLD + int "SIGCHLD" + default 4 + depends on SCHED_HAVE_PARENT + ---help--- + The SIGCHLD signal is sent to the parent of a child process when it + exits, is interrupted (stopped), or resumes after being interrupted. + Default: 4 + +config SIG_SIGCONDTIMEDOUT + int "SIGCONDTIMEDOUT" + default 16 + depends on !DISABLE_PTHREAD + ---help--- + This non-standard signal number is used the implementation of + pthread_cond_timedwait(). Default 16. + +config SIG_SIGWORK + int "SIGWORK" + default 17 + depends on SCHED_WORKQUEUE + ---help--- + SIGWORK is a non-standard signal used to wake up the internal NuttX + worker thread. This setting specifies the signal number that will be + used for SIGWORK. Default: 17 + +endif + comment "Sizes of configurable things (0 disables)" config MAX_TASKS - int "Max tasks" + int "Max number of tasks" default 32 ---help--- The maximum number of simultaneously active tasks. This value must be @@ -327,33 +461,32 @@ config MAX_TASK_ARGS receive (i.e., maxmum value of 'argc') config NPTHREAD_KEYS - int "Number of pthread keys" + int "Maximum number of pthread keys" default 4 ---help--- The number of items of thread- specific data that can be retained config NFILE_DESCRIPTORS - int "Max file descriptors" + int "Maximum number of file descriptors per task" default 16 ---help--- - The maximum number of file - descriptors (one for each open) + The maximum number of file descriptors per task (one for each open) config NFILE_STREAMS - int "Max file streams" + int "Maximum number of FILE streams" default 16 ---help--- The maximum number of streams that can be fopen'ed config NAME_MAX - int "name max" + int "Maximum size of a file name" default 32 ---help--- The maximum size of a file name. config PREALLOC_MQ_MSGS - int "Pre-allocated messages" + int "Number of pre-allocated messages" default 32 ---help--- The number of pre-allocated message structures. The system manages @@ -367,21 +500,20 @@ config MQ_MAXMSGSIZE setting (does not include other message structure overhead. config MAX_WDOGPARMS - int "max watchdog parms" + int "Maximum number of watchdog parameters" default 4 ---help--- - Maximum number of parameters that - can be passed to a watchdog handler + Maximum number of parameters that can be passed to a watchdog handler config PREALLOC_WDOGS - int "Pre-allocated watchdogs" + int "Number of pre-allocated watchdog timers" default 32 ---help--- The number of pre-allocated watchdog structures. The system manages a pool of preallocated watchdog structures to minimize dynamic allocations config PREALLOC_TIMERS - int "Pre-allocated timers" + int "Number of pre-allocated POSIX timers" default 8 ---help--- The number of pre-allocated POSIX timer structures. The system manages a |