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.Dd January 24, 2010 .Dt SYSMON_TASKQ 9 .Os .Sh NAME .Nm sysmon_taskq .Nd general purpose system monitoring task queue .Sh SYNOPSIS n dev/sysmon/sysmon_taskq.h .Ft void .Fn sysmon_task_queue_preinit "void" .Ft void .Fn sysmon_task_queue_init "void" .Ft void .Fn sysmon_task_queue_fini "void" .Ft int .Fn sysmon_task_queue_sched "u_int pri" "void (*func)(void *)" "void *arg" .Ft void .Fn sysmon_task_queue_barrier "u_int pri" .Sh DESCRIPTION The machine-independent .Nm provides a simple general purpose task queue. It can be used to run callbacks that require thread context, but do not warrant the use of a more fine-grained solution.
p Although the intended usage is related to the context of system monitoring and power management, also other comparable functions are suitable for .Nm . .Sh FUNCTIONS The necessary internal data structures are initialized during system startup by .Fn sysmon_task_queue_preinit . Before actual usage, a machine-dependent procedure should finish the initialization by calling .Fn sysmon_task_queue_init . This will create a kernel thread that can be later halted by .Fn sysmon_task_queue_fini . All scheduled tasks are executed before the queue is halted.
p The .Fn sysmon_task_queue_sched function enqueues .Fa func to be executed at the priority .Fa pri . If .Fa pri is 0, the scheduled function will be placed as the last element in the queue. The single argument passed to .Fa func is specified by .Fa arg .
p The .Fn sysmon_task_queue_barrier function waits for the completion of all tasks at .Fa pri or lower currently queued at the time of the call. .Sh RETURN VALUES Upon successful completion, .Fn sysmon_task_queue_sched returns 0. Otherwise, the following error values are returned: l -tag -width [EINVAL] t Bq Er EINVAL An invalid parameter was specified. t Bq Er ENOMEM There was not enough memory. .El .Sh SEE ALSO .Xr queue 3 , .Xr kthread 9 , .Xr workqueue 9 .Sh AUTHORS .An Jason R. Thorpe Aq Mt thorpej@NetBSD.org