|SPU_CREATE(2)||Linux Programmer's Manual||SPU_CREATE(2)|
NAMEspu_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,
Note: There is no glibc wrapper for this system call; see NOTES.
DESCRIPTIONThe spu_create() 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 pathname and returns a file descriptor associated with it. pathname must refer to a nonexistent directory in the mount point of the SPU file system ( spufs). If spu_create() is successful, a directory is created at pathname and it is populated with the files described in spufs(7).
- 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.)
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.
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.
- 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.
The mode argument (minus any bits set in the process's umask(2)) specifies the permissions used for creating the new directory in spufs. See stat(2) for a full list of the possible mode values.
RETURN VALUEOn 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 path name.
- 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 pathname.
- The process has reached its maximum open files limit.
- pathname is too long.
- The system has reached the global open files limit.
- 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 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 loaded.
- 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.
FILESpathname must point to a location beneath the mount point of spufs. By convention, it gets mounted in /spu.
VERSIONSThe spu_create() system call was added to Linux in kernel 2.6.16.
CONFORMING TOThis call is Linux-specific and implemented only on the PowerPC architecture. Programs using this system call are not portable.
NOTESGlibc does not provide a wrapper for this system call; call it using syscall(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 http://www.bsc.es/projects/deepcomputing/linuxoncell/ for the recommended libraries.
EXAMPLESee spu_run(2) for an example of the use of spu_create()
SEE ALSOclose(2), spu_run(2), capabilities(7), spufs(7)
COLOPHONThis page is part of release 3.53 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.