xref: /freebsd/lib/libpmc/pmc_set.3 (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
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24.Dd November 25, 2007
25.Dt PMC_SET 3
26.Os
27.Sh NAME
28.Nm pmc_set
29.Nd set the reload count of a sampling PMC
30.Sh LIBRARY
31.Lb libpmc
32.Sh SYNOPSIS
33.In pmc.h
34.Ft int
35.Fn pmc_set "pmc_id_t pmc" "pmc_value_t value"
36.Sh DESCRIPTION
37Function
38.Fn pmc_set
39is used to set the reload value of sampling PMCs.
40Argument
41.Fa pmc
42specified the handle a previously allocate sampling mode PMC.
43Argument
44.Fa value
45specifies the reload count.
46.Pp
47Sampling PMCs will interrupt the CPU after the number of
48hardware events specified by the reload count are seen.
49After the sampling interrupt is processed the underlying hardware will
50be reloaded with the specified count and the hardware
51automatically restarted by
52.Xr hwpmc 4 .
53.Pp
54Function
55.Fn pmc_set
56should be called on PMC in a quiescent state.
57.Sh RETURN VALUES
58.Rv -std pmc_set
59.Sh ERRORS
60A call to
61.Fn pmc_set
62may fail with the following errors:
63.Bl -tag -width Er
64.It Bq Er EINVAL
65The current process did not own a PMC with the specified handle.
66.It Bq Er EBUSY
67The specified PMC was already running.
68.El
69.Sh SEE ALSO
70.Xr pmc 3 ,
71.Xr hwpmc 4
72