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linux/arch/powerpc/platforms/cell/spufs/context.c
Christoph Hellwig 9d78592ed7 [POWERPC] spusched: Fix initial timeslice calculation
Currently we calculate the first timeslice for every context
incorrectly - alloc_spu_context calls spu_set_timeslice before we set
ctx->prio so we always calculate the longest possible timeslice for the
lowest possible priority.

This patch makes sure to update the schedule-related fields before
calculating the timeslice and also makes sure we update the timeslice for
a non-running context when entering spu_run so a priority change affects
the context as soon as possible.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-07-26 16:17:56 +10:00

209 lines
5.1 KiB
C

/*
* SPU file system -- SPU context management
*
* (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.
*/
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <asm/atomic.h>
#include <asm/spu.h>
#include <asm/spu_csa.h>
#include "spufs.h"
atomic_t nr_spu_contexts = ATOMIC_INIT(0);
struct spu_context *alloc_spu_context(struct spu_gang *gang)
{
struct spu_context *ctx;
ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
if (!ctx)
goto out;
/* Binding to physical processor deferred
* until spu_activate().
*/
if (spu_init_csa(&ctx->csa))
goto out_free;
spin_lock_init(&ctx->mmio_lock);
mutex_init(&ctx->mapping_lock);
kref_init(&ctx->kref);
mutex_init(&ctx->state_mutex);
mutex_init(&ctx->run_mutex);
init_waitqueue_head(&ctx->ibox_wq);
init_waitqueue_head(&ctx->wbox_wq);
init_waitqueue_head(&ctx->stop_wq);
init_waitqueue_head(&ctx->mfc_wq);
ctx->state = SPU_STATE_SAVED;
ctx->ops = &spu_backing_ops;
ctx->owner = get_task_mm(current);
INIT_LIST_HEAD(&ctx->rq);
INIT_LIST_HEAD(&ctx->aff_list);
if (gang)
spu_gang_add_ctx(gang, ctx);
__spu_update_sched_info(ctx);
spu_set_timeslice(ctx);
ctx->stats.util_state = SPU_UTIL_IDLE_LOADED;
atomic_inc(&nr_spu_contexts);
goto out;
out_free:
kfree(ctx);
ctx = NULL;
out:
return ctx;
}
void destroy_spu_context(struct kref *kref)
{
struct spu_context *ctx;
ctx = container_of(kref, struct spu_context, kref);
mutex_lock(&ctx->state_mutex);
spu_deactivate(ctx);
mutex_unlock(&ctx->state_mutex);
spu_fini_csa(&ctx->csa);
if (ctx->gang)
spu_gang_remove_ctx(ctx->gang, ctx);
if (ctx->prof_priv_kref)
kref_put(ctx->prof_priv_kref, ctx->prof_priv_release);
BUG_ON(!list_empty(&ctx->rq));
atomic_dec(&nr_spu_contexts);
kfree(ctx);
}
struct spu_context * get_spu_context(struct spu_context *ctx)
{
kref_get(&ctx->kref);
return ctx;
}
int put_spu_context(struct spu_context *ctx)
{
return kref_put(&ctx->kref, &destroy_spu_context);
}
/* give up the mm reference when the context is about to be destroyed */
void spu_forget(struct spu_context *ctx)
{
struct mm_struct *mm;
spu_acquire_saved(ctx);
mm = ctx->owner;
ctx->owner = NULL;
mmput(mm);
spu_release(ctx);
}
void spu_unmap_mappings(struct spu_context *ctx)
{
mutex_lock(&ctx->mapping_lock);
if (ctx->local_store)
unmap_mapping_range(ctx->local_store, 0, LS_SIZE, 1);
if (ctx->mfc)
unmap_mapping_range(ctx->mfc, 0, 0x1000, 1);
if (ctx->cntl)
unmap_mapping_range(ctx->cntl, 0, 0x1000, 1);
if (ctx->signal1)
unmap_mapping_range(ctx->signal1, 0, PAGE_SIZE, 1);
if (ctx->signal2)
unmap_mapping_range(ctx->signal2, 0, PAGE_SIZE, 1);
if (ctx->mss)
unmap_mapping_range(ctx->mss, 0, 0x1000, 1);
if (ctx->psmap)
unmap_mapping_range(ctx->psmap, 0, 0x20000, 1);
mutex_unlock(&ctx->mapping_lock);
}
/**
* spu_acquire_runnable - lock spu contex and make sure it is in runnable state
* @ctx: spu contex to lock
*
* Note:
* Returns 0 and with the context locked on success
* Returns negative error and with the context _unlocked_ on failure.
*/
int spu_acquire_runnable(struct spu_context *ctx, unsigned long flags)
{
int ret = -EINVAL;
spu_acquire(ctx);
if (ctx->state == SPU_STATE_SAVED) {
/*
* Context is about to be freed, so we can't acquire it anymore.
*/
if (!ctx->owner)
goto out_unlock;
ret = spu_activate(ctx, flags);
if (ret)
goto out_unlock;
}
return 0;
out_unlock:
spu_release(ctx);
return ret;
}
/**
* spu_acquire_saved - lock spu contex and make sure it is in saved state
* @ctx: spu contex to lock
*/
void spu_acquire_saved(struct spu_context *ctx)
{
spu_acquire(ctx);
if (ctx->state != SPU_STATE_SAVED) {
set_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags);
spu_deactivate(ctx);
}
}
/**
* spu_release_saved - unlock spu context and return it to the runqueue
* @ctx: context to unlock
*/
void spu_release_saved(struct spu_context *ctx)
{
BUG_ON(ctx->state != SPU_STATE_SAVED);
if (test_and_clear_bit(SPU_SCHED_WAS_ACTIVE, &ctx->sched_flags))
spu_activate(ctx, 0);
spu_release(ctx);
}
void spu_set_profile_private_kref(struct spu_context *ctx,
struct kref *prof_info_kref,
void ( * prof_info_release) (struct kref *kref))
{
ctx->prof_priv_kref = prof_info_kref;
ctx->prof_priv_release = prof_info_release;
}
EXPORT_SYMBOL_GPL(spu_set_profile_private_kref);
void *spu_get_profile_private_kref(struct spu_context *ctx)
{
return ctx->prof_priv_kref;
}
EXPORT_SYMBOL_GPL(spu_get_profile_private_kref);