sysmp(2)sysmp(2)NAMEsysmp - 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, ...);"
DESCRIPTIONsysmp 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
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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.
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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).
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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.
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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.
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[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.
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[EFAULT] An invalid buffer address has been supplied by the calling
process.
SEE ALSOmpadmin(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.
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