linux/arch/powerpc/platforms/cell/spufs/spufs.h
Christoph Hellwig 2eb1b12049 [POWERPC] spu sched: static timeslicing for SCHED_RR contexts
For SCHED_RR tasks we can do some really trivial timeslicing.  Basically
we fire up a time for every scheduler tick that searches for a higher
or same priority thread that is on the runqueue and if there is one
context switches to it.  Because we can't lock spus from timer context
we actually run this from a delayed runqueue instead of a timer.

A nice optimization would be to skip the actual priority bitmap search
when there are less contexts than physical spus available.  To implement
this I need a so far unpublished patch from Andre, and it will be added
after we have that patch in.

Note that right now we only do the time slicing for SCHED_RR tasks.
The code would work for SCHED_OTHER tasks aswell, but their prio
value is defered from the one the PPU thread has at time of spu_run,
and using this for spu scheduling decisions would make the code very
unfair.  SCHED_OTHER support will be enabled once we the spu scheduler
knows how to calculcate cpu_context.prio (very soon)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com>
2007-02-13 21:55:43 +01:00

257 lines
7.9 KiB
C

/*
* SPU file system
*
* (C) Copyright IBM Deutschland Entwicklung GmbH 2005
*
* Author: Arnd Bergmann <arndb@de.ibm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef SPUFS_H
#define SPUFS_H
#include <linux/kref.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/fs.h>
#include <asm/spu.h>
#include <asm/spu_csa.h>
#include <asm/spu_info.h>
/* The magic number for our file system */
enum {
SPUFS_MAGIC = 0x23c9b64e,
};
struct spu_context_ops;
struct spu_gang;
/* ctx->sched_flags */
enum {
SPU_SCHED_WAKE = 0,
};
struct spu_context {
struct spu *spu; /* pointer to a physical SPU */
struct spu_state csa; /* SPU context save area. */
spinlock_t mmio_lock; /* protects mmio access */
struct address_space *local_store; /* local store mapping. */
struct address_space *mfc; /* 'mfc' area mappings. */
struct address_space *cntl; /* 'control' area mappings. */
struct address_space *signal1; /* 'signal1' area mappings. */
struct address_space *signal2; /* 'signal2' area mappings. */
struct address_space *mss; /* 'mss' area mappings. */
struct address_space *psmap; /* 'psmap' area mappings. */
u64 object_id; /* user space pointer for oprofile */
enum { SPU_STATE_RUNNABLE, SPU_STATE_SAVED } state;
struct mutex state_mutex;
struct semaphore run_sema;
struct mm_struct *owner;
struct kref kref;
wait_queue_head_t ibox_wq;
wait_queue_head_t wbox_wq;
wait_queue_head_t stop_wq;
wait_queue_head_t mfc_wq;
struct fasync_struct *ibox_fasync;
struct fasync_struct *wbox_fasync;
struct fasync_struct *mfc_fasync;
u32 tagwait;
struct spu_context_ops *ops;
struct work_struct reap_work;
unsigned long flags;
unsigned long event_return;
struct list_head gang_list;
struct spu_gang *gang;
/* scheduler fields */
struct list_head rq;
struct delayed_work sched_work;
unsigned long sched_flags;
unsigned long rt_priority;
int policy;
int prio;
};
struct spu_gang {
struct list_head list;
struct mutex mutex;
struct kref kref;
int contexts;
};
struct mfc_dma_command {
int32_t pad; /* reserved */
uint32_t lsa; /* local storage address */
uint64_t ea; /* effective address */
uint16_t size; /* transfer size */
uint16_t tag; /* command tag */
uint16_t class; /* class ID */
uint16_t cmd; /* command opcode */
};
/* SPU context query/set operations. */
struct spu_context_ops {
int (*mbox_read) (struct spu_context * ctx, u32 * data);
u32(*mbox_stat_read) (struct spu_context * ctx);
unsigned int (*mbox_stat_poll)(struct spu_context *ctx,
unsigned int events);
int (*ibox_read) (struct spu_context * ctx, u32 * data);
int (*wbox_write) (struct spu_context * ctx, u32 data);
u32(*signal1_read) (struct spu_context * ctx);
void (*signal1_write) (struct spu_context * ctx, u32 data);
u32(*signal2_read) (struct spu_context * ctx);
void (*signal2_write) (struct spu_context * ctx, u32 data);
void (*signal1_type_set) (struct spu_context * ctx, u64 val);
u64(*signal1_type_get) (struct spu_context * ctx);
void (*signal2_type_set) (struct spu_context * ctx, u64 val);
u64(*signal2_type_get) (struct spu_context * ctx);
u32(*npc_read) (struct spu_context * ctx);
void (*npc_write) (struct spu_context * ctx, u32 data);
u32(*status_read) (struct spu_context * ctx);
char*(*get_ls) (struct spu_context * ctx);
u32 (*runcntl_read) (struct spu_context * ctx);
void (*runcntl_write) (struct spu_context * ctx, u32 data);
void (*master_start) (struct spu_context * ctx);
void (*master_stop) (struct spu_context * ctx);
int (*set_mfc_query)(struct spu_context * ctx, u32 mask, u32 mode);
u32 (*read_mfc_tagstatus)(struct spu_context * ctx);
u32 (*get_mfc_free_elements)(struct spu_context *ctx);
int (*send_mfc_command)(struct spu_context * ctx,
struct mfc_dma_command * cmd);
void (*dma_info_read) (struct spu_context * ctx,
struct spu_dma_info * info);
void (*proxydma_info_read) (struct spu_context * ctx,
struct spu_proxydma_info * info);
};
extern struct spu_context_ops spu_hw_ops;
extern struct spu_context_ops spu_backing_ops;
struct spufs_inode_info {
struct spu_context *i_ctx;
struct spu_gang *i_gang;
struct inode vfs_inode;
};
#define SPUFS_I(inode) \
container_of(inode, struct spufs_inode_info, vfs_inode)
extern struct tree_descr spufs_dir_contents[];
extern struct tree_descr spufs_dir_nosched_contents[];
/* system call implementation */
long spufs_run_spu(struct file *file,
struct spu_context *ctx, u32 *npc, u32 *status);
long spufs_create(struct nameidata *nd,
unsigned int flags, mode_t mode);
extern const struct file_operations spufs_context_fops;
/* gang management */
struct spu_gang *alloc_spu_gang(void);
struct spu_gang *get_spu_gang(struct spu_gang *gang);
int put_spu_gang(struct spu_gang *gang);
void spu_gang_remove_ctx(struct spu_gang *gang, struct spu_context *ctx);
void spu_gang_add_ctx(struct spu_gang *gang, struct spu_context *ctx);
/* context management */
static inline void spu_acquire(struct spu_context *ctx)
{
mutex_lock(&ctx->state_mutex);
}
static inline void spu_release(struct spu_context *ctx)
{
mutex_unlock(&ctx->state_mutex);
}
struct spu_context * alloc_spu_context(struct spu_gang *gang);
void destroy_spu_context(struct kref *kref);
struct spu_context * get_spu_context(struct spu_context *ctx);
int put_spu_context(struct spu_context *ctx);
void spu_unmap_mappings(struct spu_context *ctx);
void spu_forget(struct spu_context *ctx);
int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags);
void spu_acquire_saved(struct spu_context *ctx);
int spu_acquire_exclusive(struct spu_context *ctx);
enum {
SPU_ACTIVATE_NOWAKE = 1,
};
int spu_activate(struct spu_context *ctx, unsigned long flags);
void spu_deactivate(struct spu_context *ctx);
void spu_yield(struct spu_context *ctx);
void spu_start_tick(struct spu_context *ctx);
void spu_stop_tick(struct spu_context *ctx);
void spu_sched_tick(struct work_struct *work);
int __init spu_sched_init(void);
void __exit spu_sched_exit(void);
extern char *isolated_loader;
/*
* spufs_wait
* Same as wait_event_interruptible(), except that here
* we need to call spu_release(ctx) before sleeping, and
* then spu_acquire(ctx) when awoken.
*/
#define spufs_wait(wq, condition) \
({ \
int __ret = 0; \
DEFINE_WAIT(__wait); \
for (;;) { \
prepare_to_wait(&(wq), &__wait, TASK_INTERRUPTIBLE); \
if (condition) \
break; \
if (!signal_pending(current)) { \
spu_release(ctx); \
schedule(); \
spu_acquire(ctx); \
continue; \
} \
__ret = -ERESTARTSYS; \
break; \
} \
finish_wait(&(wq), &__wait); \
__ret; \
})
size_t spu_wbox_write(struct spu_context *ctx, u32 data);
size_t spu_ibox_read(struct spu_context *ctx, u32 *data);
/* irq callback funcs. */
void spufs_ibox_callback(struct spu *spu);
void spufs_wbox_callback(struct spu *spu);
void spufs_stop_callback(struct spu *spu);
void spufs_mfc_callback(struct spu *spu);
void spufs_dma_callback(struct spu *spu, int type);
extern struct spu_coredump_calls spufs_coredump_calls;
struct spufs_coredump_reader {
char *name;
ssize_t (*read)(struct spu_context *ctx,
char __user *buffer, size_t size, loff_t *pos);
u64 (*get)(void *data);
size_t size;
};
extern struct spufs_coredump_reader spufs_coredump_read[];
extern int spufs_coredump_num_notes;
#endif