pset_create

, pset_destroy

, pset_assign

- manage sets of processors

Synopsis

#include <sys/pset.h>

int pset_create(psetid_t *newpset);

int pset_destroy(psetid_t pset);

int pset_assign(psetid_t pset, processorid_t cpu, psetid_t *opset);

Description

These functions control the creation and management of sets of processors. Processor sets allow a subset of the system's processors to be set aside for exclusive use by specified LWPs and processes. The binding of LWPs and processes to processor sets is controlled by pset_bind(2).

The pset_create() function creates an empty processor set that contains no processors. On successful return, newpset will contain the ID of the new processor set.

The pset_destroy() function destroys the processor set pset, releasing its constituent processors and processes. If pset is PS_MYID, the processor set to which the caller is bound is destroyed.

The pset_assign() function assigns the processor cpu to the processor set pset. A processor that has been assigned to a processor set will run only LWPs and processes that have been explicitly bound to that processor set, unless another LWP requires a resource that is only available on that processor.

On successful return, if opset is non-null, opset will contain the processor set ID of the former processor set of the processor.

If pset is PS_NONE, pset_assign() releases processor cpu from its current processor set.

If pset is PS_QUERY, pset_assign() makes no change to processor sets, but returns the current processor set ID of processor cpu in opset.

If pset is PS_MYID, processor cpu is assigned to the processor set to which the caller belongs. If the caller does not belong to a processor set, processor cpu is released from its current processor set.

These functions are restricted to privileged processes, except for pset_assign() when pset is PS_QUERY.

Return Values

Upon successful completion, these functions return 0. Otherwise, -1 is returned and errno is set to indicate the error.

Errors

These functions will fail if:

EBUSY

The processor could not be moved to the specified processor set.

EFAULT

The location pointed to by newpset was not writable by the user, or the location pointed to by opset was not NULL and not writable by the user.

EINVAL

The specified processor does not exist, the specified processor is not on-line, or an invalid processor set was specified.

ENOMEM

There was insufficient space for pset_create to create a new processor set.

ENOTSUP

The pools facility is active. See pooladm(1M) and pool_set_status(3POOL) for information about enabling and disabling the pools facility.

EPERM

The {PRIV_SYS_RES_CONFIG} privilege is not asserted in the effective set of the calling process.

Attributes

See attributes(5) for descriptions of the following attributes:

See Also

pooladm(1M), psradm(1M), psrinfo(1M), psrset(1M), p_online(2), processor_bind(2), pset_bind(2), pset_info(2), pool_set_status(3POOL), pset_getloadavg(3C), attributes(5), privileges(5)

Notes

The processor set type of PS_SYSTEM is no longer supported.

Processors with LWPs bound to them using processor_bind(2) cannot be assigned to a new processor set. If this is attempted, pset_assign() will fail and set errno to EBUSY.