sysmp(2)                                                              sysmp(2)


NAME
     sysmp - multiprocessing control

C SYNOPSIS
     #include <sys/types.h>
     #include <sys/sysmp.h>
     #include <sys/sysinfo.h> /* for SAGET and MINFO structures */
     int sysmp (int cmd, ...);
     ptrdiff_t sysmp (int cmd, ...);"

DESCRIPTION
     sysmp provides control over and information about miscellaneous system
     services.  This system call is usually used by system programs and is not
     intended for general use.  The arguments arg1, arg2, arg3, arg4 are
     provided for command-dependent use.

     As specified by cmd, the following commands are available:

     MP_CLEARCFSSTAT
     MP_CLEARNFSSTAT
     MP_NUMA_GETCPUNODEMAP
     MP_NUMA_GETDISTMATRIX
                    These are all interfaces that are used to implement
                    various system library functions.  They are all subject to
                    change and should not be called directly by applications.

     MP_PGSIZE      The page size of the system is returned (see
                    getpagesize(2)).

     MP_SCHED       Interface for the schedctl(2) system call.

     MP_NPROCS      Returns the number of processors physically configured.

     MP_NAPROCS     Returns the number of processors that are available to
                    schedule unrestricted processes.

     MP_STAT        The processor ids and status flag bits of the physically
                    configured processors are copied into an array of pda_stat
                    structures to which arg1 points.  The array must be large
                    enough to hold as many pda_stat structures as the number
                    of processors returned by the MP_NPROCS sysmp command.
                    The pda_stat structure and the various status bits are
                    defined in <sys/pda.h>.

     MP_EMPOWER     The processor number given by arg1, interpreted as an
                    'int', is empowered to run any unrestricted processes.
                    This is the default for all processors.  This command
                    requires superuser authority.

     MP_RESTRICT    The processor number given by arg1, interpreted as an
                    'int', is restricted from running any processes except
                    those assigned to it by a MP_MUSTRUN or MP_MUSTRUN_PID


                    command, a runon(1) command or because of hardware
                    necessity.  Note that processor 0 cannot be restricted.
                    This command requires superuser authority.  On Challenge
                    Series machines, all timers belonging to the processor are
                    moved to the processor that owns the clock as reported by
                    MP_CLOCK.

     MP_ISOLATE     The processor number given by arg1, interpreted as an
                    'int', is isolated from running any processes except those
                    assigned to it by a MP_MUSTRUN command, a runon(1) command
                    or because of hardware necessity.  Instruction cache and
                    Translation Lookaside Buffer synchronization across
                    processors in the system is minimized or delayed on an
                    isolated processor until system services are requested.
                    Note that processor 0 cannot be isolated.  This command
                    requires superuser authority.  On Challenge Series
                    machines, all timers belonging to the processor are moved
                    to the processor that owns the clock as reported by
                    MP_CLOCK.

     MP_UNISOLATE   The processor number given by arg1, interpreted as an
                    'int', is unisolated and empowered to run any unrestricted
                    processes.  This is the default system configuration for
                    all processors.  This command requires superuser
                    authority.

     MP_PREEMPTIVE  The processor number given by arg1, interpreted as an
                    'int', has its clock scheduler enabled.  This is the
                    default for all processors.  Note that this command
                    implies MP_PERMITRTC which can be seen below.  Clock
                    scheduling cannot be changed on an excluded processor.
                    This command requires superuser authority.

     MP_NONPREEMPTIVE
                    The processor number given by arg1, interpreted as an
                    'int', has its clock scheduler disabled.  Normal process
                    time slicing is no longer enforced on that processor.  As
                    a result of turning off the clock interrupt, the interrupt
                    latency on this processor will be lower.  Note that this
                    command implies MP_WARDRTC which can be seen below.  The
                    Real-Time Clock can be re-permitted by a subsequent use of
                    MP_PERMITRTC if so desired.  This command requires
                    superuser authority and is allowed only on an isolated
                    processor.  Clock scheduling cannot be changed on an
                    excluded processor.  This command is not allowed on the
                    clock processor (see MP_CLOCK).

     MP_CLOCK       The processor number given by arg1, interpreted as an
                    'int', is given charge of the operating system software
                    clock (see timers(5)).  Clock handling cannot be assigned
                    to an excluded processor.  This command requires superuser
                    authority.


     MP_FASTCLOCK   The processor number given by arg1, interpreted as an
                    'int', is given charge of the operating system software
                    fast clock (see timers(5)).  Clock handling cannot be
                    assigned to an excluded processor.  This command requires
                    superuser authority.

     MP_WARDRTC     The processor number given by arg1, interpreted as an
                    'int', queues interrupts from the Real-Time Clock (RTC)
                    created by timeouts and interval timers created by threads
                    running on the processor to other processors.  RTC
                    interrupts will not be queueable to the processor from
                    other processors.  This command is not allowed on the
                    Clock processor nor processor 0.  This command requires
                    superuser authority.

     MP_PERMITRTC   The processor number given by arg1, interpreted as an
                    'int', will be permitted to handle RTC interrupts created
                    by timeouts and interval timers.  This command requires
                    superuser authority.

          MP_MISER_GETREQUEST
          MP_MISER_SENDREQUEST
          MP_MISER_RESPOND
          MP_MISER_GETRESOURCE
          MP_MISER_SETRESOURCE
     MP_MISER_CHECKACCESS
                    These are all interfaces that are used to implement
                    various miser(1) functions.  These are all subject to
                    change and should not be called directly by applications.
     MP_MUSTRUN
          Assigns the calling process to run only on the processor number by
          arg1, interpreted as an 'int', except as required for communications
          with hardware devices.  After a sucessful assignment to a cpu, any
          subsequent fork or sproc call that creates a new process is also
          assigned to the same cpu as the parent (see fork(2) and sproc(2)).
          Processes cannot be assigned to an excluded processor. A process
          that has allocated a CC sync register (see ccsync(7m)) is restricted
          to running on a particular cpu.  Attempts to reassign such a process
          to another cpu will fail until the CC sync register has been
          relinquished. This command should not be used within a pthreaded
          application (see pthread_setrunon_np(3P)). There are two tuneable
          system parameters in the dynamic parameter group miser that affect
          the operation of MP_MUSTRUN.  The boolean parameter cpuset_nobind,
          if set to '0' or false, has no affect.  When this parameter is set
          to '1' (true), no process running in a cpuset can assign itself or
          child to any CPU.  The boolean parameter cpuset_tobind, if set to
          '0' or false, has no affect.  When this parameter is set to '1'
          (true), the CPU being bound to must be restricted, isolated, or part
          of a cpuset(1).


     MP_MUSTRUN_PID
          Assigns the process specified by arg2 to run only on the processor
          number specified by arg1, both interpreted as 'int', except as
          required for communications with hardware devices.  After a
          sucessful assignment to a cpu, any subsequent fork or sproc call
          performed by the specified process that creates a new process is
          also assigned to the same cpu as the parent (see fork(2) and
          sproc(2)).  Processes cannot be assigned to an excluded processor.
          A process that has allocated a CC sync register (see ccsync(7m)) is
          restricted to running on a particular cpu.  Attempts to reassign
          such a process to another cpu will fail until the CC sync register
          has been relinquished.  This command will give unpredictable results
          if the specified process is a pthreaded process.  There are two
          tuneable system parameters in the dynamic parameter group miser that
          affect the operation of MP_MUSTRUN_PID.  The boolean parameter
          cpuset_nobind, if set to '0' or false, has no affect.  When this
          parameter is set to '1' (true), no process running in a cpuset can
          assign itself or child to any CPU.  The boolean parameter
          cpuset_tobind, if set to '0' or false, has no affect.  When this
          parameter is set to '1' (true), the CPU being bound to must be
          restricted, isolated, or part of a cpuset(1).

     MP_GETMUSTRUN
          Returns the processor the current process has been set to run on
          using the MP_MUSTRUN command.  If the current process has not been
          assigned to a specific processor, -1 is returned and errno is set to
          EINVAL.  This command should not be used within a pthreaded
          application (see pthread_setrunon_np(3P)).

     MP_GETMUSTRUN_PID
          Returns the processor that the process specified by arg1 has been
          set to run on using the MP_MUSTRUN or MP_MUSTRUN_PID command.  If
          the process has not been assigned to a specific processor, -1 is
          returned and errno is set to EINVAL.  This command will give
          unpredictable results if the specified process is a pthreaded
          process.

     MP_RUNANYWHERE
          Frees the calling process to run on whatever processor the system
          deems suitable.

     MP_RUNANYWHERE_PID
          Frees the process specified by arg1 to run on whatever processor the
          system deems suitable.

     MP_KERNADDR
          Returns the address of various kernel data structures.  The
          structure returned is selected by arg1.  The list of available
          structures is detailed in <sys/sysmp.h>.  This option is used by
          many system programs to avoid having to look in /unix for the
          location of the data structures.


     MP_SASZ
          Returns the size of various system accounting structures.  As above,
          the structure returned is governed by arg1.

     MP_SAGET1
          Returns the contents of various system accounting structures.  The
          information is only for the processor specified by arg4.  As above,
          the structure returned is governed by arg1.  arg2 points to a buffer
          in the address space of the calling process and arg3 specifies the
          maximum number of bytes to transfer.

     MP_SAGET
          Returns the contents of various system accounting structures.  The
          information is summed across all processors before it is returned.
          As above, the structure returned is governed by arg1.  arg2 points
          to a buffer in the address space of the calling process and arg3
          specifies the maximum number of bytes to transfer.

     MP_EXCLUDE
          The processor number given by arg1, interpreted as an 'int', is
          excluded from system use.  Currently, this includes isolation in the
          same manner as the MP_ISOLATE command.  In addition, the MP_EMPOWER,
          MP_RESTRICT, MP_ISOLATE, MP_UNISOLATE, MP_CLOCK, MP_FASTCLOCK,
          MP_PREEMPTIVE, MP_NONPREEMPTIVE, MP_MUSTRUN and MP_MUSTRUNPID
          commands cannot be applied to an excluded processor.  This command
          requires superuser authority.  On Challenge Series machines, all
          timers belonging to the processor are moved to the processor that
          owns the clock as reported by Note that processor 0 cannot be
          excluded.

     MP_UNEXCLUDE
          The processor number given by arg1, interpreted as an 'int', is
          unexcluded and empowered to run any unrestricted processes.  This is
          the default system configuration for all processors.  This command
          requires superuser authority.

     Possible errors from sysmp are:

     [EACCES]    An attempt to bind a thread to a CPU using MP_MUSTRUN or
                 MP_MUSTRUN_PID was made with the system tuneable parameter
                 cpuset_tobind set to '1', and the CPU was not restricted,
                 isolated, or part of a cpuset.

     [EPERM]     The effective user ID is not superuser.  Many of the commands
                 require superuser privilege.

     [EPERM]     The user ID of the sending process is not superuser, and its
                 real or effective user ID does not match the real, saved,  or
                 effective user ID of the receiving process.


     [ESRCH]     No process corresponding to that specified by a
                 MP_MUSTRUN_PID, MP_GETMUSTRUN_PID, or MP_RUNANYWHERE_PID
                 could be found.

     [EINVAL]    The processor named by a MP_EMPOWER, MP_RESTRICT, MP_ISOLATE,
                 MP_UNISOLATE, MP_CLOCK, MP_FASTCLOCK, MP_PREEMPTIVE,
                 MP_NONPREEMPTIVE, MP_MUSTRUN, MP_MUSTRUNPID, MP_PERMITRTC or
                 MP_WARDRTC command does not exist.

     [EINVAL]    The cmd argument is invalid.

     [EINVAL]    The arg1 argument to a MP_KERNADDR command is invalid.

     [EINVAL]    An attempt was made via MP_MUSTRUN or MP_MUSTRUN_PID to move
                 a process owning a CC sync register from the cpu controlling
                 the CC sync register.

     [EINVAL]    The target of the MP_GETMUSTRUN command has not been set to
                 run on a specific processor.

     [EINVAL]    The target process of the MP_MUSTRUN_PID command is a
                 pthreaded process.

     [EINVALSTATE]
                 The processor named by a MP_EMPOWER, MP_RESTRICT, MP_ISOLATE,
                 MP_UNISOLATE, MP_CLOCK, MP_FASTCLOCK, MP_PREEMPTIVE,
                 MP_NONPREEMPTIVE, MP_MUSTRUN or MP_MUSTRUNPID command is in
                 excluded state.

     [EINVALSTATE]
                 The processor named by a MP_EMPOWER command is in isolated
                 state.

     [EINVALSTATE]
                 The processor names by a MP_CLOCK command is in RTC warded
                 state.

     [EINVALSTATE]
                 The processor named by a MP_WARDRTC command is running the
                 operating system software clock.

     [EBUSY]     An attempt was made to restrict the only unrestricted
                 processor or to restrict the master processor.

     [EBUSY]     The processor named by an MP_EXCLUDE command is currently
                 running processes assigned by the MP_MUSTRUN or MP_MUSTRUNPID
                 commands.

     [EBUSY]     The processor named by an MP_UNISOLATE command is currently
                 running in non-preemptive mode.


     [EFAULT]    An invalid buffer address has been supplied by the calling
                 process.

SEE ALSO
     mpadmin(1), runon(1), getpagesize(2), schedctl(2),
     pthread_setrunon_np(3P), timers(5)

DIAGNOSTICS
     Upon successful completion, the cmd dependent data is returned.
     Otherwise, a value of -1 is returned and errno is set to indicate the
     error.


                                                                        Page 7