DTRACE_CALLOUT_EXECUTE(4)                     FreeBSD Kernel Interfaces Manual

NAME

     dtrace_callout_execute - a DTrace provider for the callout API

SYNOPSIS

     callout_execute:kernel::callout_start
     callout_execute:kernel::callout_end

DESCRIPTION

     The callout_execute provider allows for tracing the callout(9) mechanism.

     The callout_execute:kernel::callout_start probe fires just before a
     callout.

     The callout_execute:kernel::callout_end probe fires right after a
     callout.

     The only argument to the callout_execute probes, args[0], is a callout
     handler struct callout * of the invoked callout.

EXAMPLES

Example 1: Graph of Callout Execution Time

     The following d(7) script generates a distribution graph of callout(9)
     execution times:

       callout_execute:::callout_start
       {
           self->cstart = timestamp;
       }

       callout_execute:::callout_end
       {
           @length = quantize(timestamp - self->cstart);
       }

SEE ALSO

     dtrace(1), tracing(7), callout(9), SDT(9)

AUTHORS

     The callout_execute provider was written by Robert N. M. Watson
     <rwatson@FreeBSD.org>.

     This manual page was written by Mateusz Piotrowski <0mp@FreeBSD.org>.

FreeBSD 15.1-STABLE-HBSD       November 4, 2025      DTRACE_CALLOUT_EXECUTE(4)