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PMC_SET(3) FreeBSD Library Functions Manual PMC_SET(3)
NAME
pmc_set - set the reload count of a sampling PMC
LIBRARY
Performance Counters Library (libpmc, -lpmc)
SYNOPSIS
#include <pmc.h>
int
pmc_set(pmc_id_t pmc, pmc_value_t value);
DESCRIPTION
Function pmc_set() is used to set the reload value of sampling PMCs.
Argument pmc specified the handle a previously allocate sampling mode
PMC. Argument value specifies the reload count.
Sampling PMCs will interrupt the CPU after the number of hardware events
specified by the reload count are seen. After the sampling interrupt is
processed the underlying hardware will be reloaded with the specified
count and the hardware automatically restarted by hwpmc(4).
Function pmc_set() should be called on PMC in a quiescent state.
RETURN VALUES
The pmc_set() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
A call to pmc_set() may fail with the following errors:
[EINVAL] The current process did not own a PMC with the
specified handle.
[EBUSY] The specified PMC was already running.
SEE ALSO
pmc(3), hwpmc(4)
FreeBSD 14.2-RELEASE November 25, 2007 FreeBSD 14.2-RELEASE