spu_create - create a new spu context
int spu_create(const char *pathname, int flags, mode_t mode);
int spu_create(const char *pathname, int flags, mode_t mode,
: There is no glibc wrapper for this system call; see NOTES.
() 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 filesystem (spufs
). If spu_create
() is successful, a
directory is created at pathname
and it is populated with the files
described in spufs
When a context is created, the returned file descriptor can only be passed to
(2), used as the dirfd
argument to the *at
of system calls (e.g., openat
(2)), or closed; other operations are not
defined. A logical SPU context is destroyed (along with all files created
within the context's pathname
directory) once the last reference to the
context has gone; this usually occurs when the file descriptor returned by
() is closed.
argument can be zero or any bitwise OR-ed combination of the
- Rather than using signals for reporting DMA errors, use the
event argument to spu_run(2).
- 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 pathname argument. This gang may be used to hold other SPU
contexts, by providing a pathname that is within the gang directory to
further calls to spu_create().
- 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 SPU_CREATE_NOSCHED contexts. Only a
subset of the files will be available in this context directory in
spufs. Additionally, SPU_CREATE_NOSCHED contexts cannot dump
a core file when crashing.
- Creating SPU_CREATE_NOSCHED contexts requires the
- Create an isolated SPU context. Isolated contexts are
protected from some PPE (PowerPC Processing Element) operations, such as
access to the SPU local store and the NPC register.
- Creating SPU_CREATE_ISOLATE contexts also requires
the SPU_CREATE_NOSCHED flag.
- 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 neighbor_fd argument.
- 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 umask
specifies the permissions used for creating the new directory in spufs
(2) for a full list of the possible mode
On success, spu_create
() returns a new file descriptor. On error, -1 is
returned, and errno
is set to one of the error codes listed below.
- The current user does not have write access to the
spufs(7) mount point.
- An SPU context already exists at the given pathname.
- pathname is not a valid string pointer in the
calling process's address space.
- pathname is not a directory in the spufs(7)
mount point, or invalid flags have been provided.
- Too many symbolic links were found while resolving
- The per-process limit on the number of open file
descriptors has been reached.
- pathname is too long.
- The system-wide limit on the total number of open files has
- An isolated context was requested, but the hardware does
not support SPU isolation.
- Part of pathname 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
- The functionality is not provided by the current system,
because either the hardware does not provide SPUs or the spufs module is
- A part of pathname is not a directory.
- The SPU_CREATE_NOSCHED flag has been given, but the
user does not have the CAP_SYS_NICE capability.
must point to a location beneath the mount point of
. By convention, it gets mounted in /spu
() system call was added to Linux in kernel 2.6.16.
This call is Linux-specific and implemented only on the PowerPC architecture.
Programs using this system call are not portable.
Glibc does not provide a wrapper for this system call; call it using
(2). Note however, that spu_create
() is meant to be used
from libraries that implement a more abstract interface to SPUs, not to be
used from regular applications. See
for the recommended libraries.
(2) for an example of the use of spu_create
This page is part of release 4.13 of the Linux man-pages
description of the project, information about reporting bugs, and the latest
version of this page, can be found at