Section: Linux Programmer's Manual (2)Updated: 2007-12-20Local indexUp
spu_create - create a new spu context
#include <sys/types.h>#include <sys/spu.h>int spu_create(const char *pathname, int flags, mode_t mode);int spu_create(const char *pathname, int flags, mode_t mode, int neighbor_fd);
system call is used on PowerPC machines that implement the
Cell Broadband Engine Architecture in order to access Synergistic
Processor Units (SPUs).
It creates a new logical context for an SPU in
and returns a file descriptor associated with it.
must refer to a nonexistent directory in the mount point of
the SPU file system
is successful, a directory is created at
and it is populated with the files described in
When a context is created,
the returned file descriptor can only be passed to
used as the
argument to the
family of system calls (e.g.,
other operations are not defined.
A logical SPU
context is destroyed (along with all files created within the context's
directory) once the last reference to the context has gone;
this usually occurs when the file descriptor returned by
argument can be zero or any bitwise OR-ed
combination of the following constants:
Rather than using signals for reporting DMA errors, use the
Create an SPU gang instead of a context.
(A gang is a group of SPU contexts that are
functionally related to each other and which share common scheduling
parameters --- priority and policy.
In the future, gang scheduling may be implemented causing
the group to be switched in and out as a single unit.)
A new directory will be created at the location specified by the
This gang may be used to hold other SPU contexts, by providing
a pathname that is within the gang directory to further calls to
Create a context that is not affected by the SPU scheduler.
Once the context is run,
it will not be scheduled out until it is destroyed by
the creating process.
Because the context cannot be removed from the SPU, some functionality
is disabled for
Only a subset of the files will be
available in this context directory in
contexts cannot dump a core file when crashing.
contexts requires the
Create an isolated SPU context.
Isolated contexts are protected from some
PPE (PowerPC Processing Element)
such as access to the SPU local store and the NPC register.
contexts also requires the
Create a context with affinity to another SPU context.
This affinity information is used within the SPU scheduling algorithm.
Using this flag requires that a file descriptor referring to
the other SPU context be passed in the
Create a context with affinity to system memory.
This affinity information
is used within the SPU scheduling algorithm.
argument (minus any bits set in the process's
specifies the permissions used for creating the new directory in
for a full list of the possible
returns a new file descriptor.
On error, -1 is returned, and
is set to one of the error codes listed below.
The current user does not have write access to the
An SPU context already exists at the given path name.
is not a valid string pointer in the
calling process's address space.
is not a directory in the
mount point, or invalid flags have been provided.
Too many symbolic links were found while resolving
The process has reached its maximum open files limit.
is too long.
The system has reached the global open files limit.
An isolated context was requested, but the hardware does not support
could not be resolved.
The kernel could not allocate all resources required.
There are not enough SPU resources available to create
a new context or the user-specific limit for the number
of SPU contexts has been reached.
The functionality is not provided by the current system, because
either the hardware does not provide SPUs or the spufs module is not
A part of
is not a directory.
flag has been given, but the user does not have the
must point to a location beneath the mount point of
By convention, it gets mounted in
system call was added to Linux in kernel 2.6.16.
This call is Linux-specific and only implemented on the PowerPC
Programs using this system call are not portable.
Glibc does not provide a wrapper for this system call; call it using
Note however, that
is meant to be used from libraries that implement a more abstract
interface to SPUs, not to be used from regular applications.
for the recommended libraries.
for an example of the use of