[POWERPC] spufs: decouple spu scheduler from spufs_spu_run (asynchronous scheduling)
Change spufs_spu_run so that the context is queued directly to the
scheduler and the controlling thread advances directly to spufs_wait()
for spe errors and exceptions.
nosched contexts are treated the same as before.
Fixes from Christoph Hellwig <hch@lst.de>
Signed-off-by: Luke Browning <lukebr@linux.vnet.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/platforms/cell/spufs/run.c b/arch/powerpc/platforms/cell/spufs/run.c
index 652ae13..b380050 100644
--- a/arch/powerpc/platforms/cell/spufs/run.c
+++ b/arch/powerpc/platforms/cell/spufs/run.c
@@ -41,21 +41,29 @@
spu->dar = 0;
}
-static inline int spu_stopped(struct spu_context *ctx, u32 *stat)
+int spu_stopped(struct spu_context *ctx, u32 *stat)
{
- struct spu *spu;
- u64 pte_fault;
+ u64 dsisr;
+ u32 stopped;
*stat = ctx->ops->status_read(ctx);
- spu = ctx->spu;
- if (ctx->state != SPU_STATE_RUNNABLE ||
- test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
+ if (test_bit(SPU_SCHED_NOTIFY_ACTIVE, &ctx->sched_flags))
return 1;
- pte_fault = ctx->csa.dsisr &
- (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED);
- return (!(*stat & SPU_STATUS_RUNNING) || pte_fault || ctx->csa.class_0_pending) ?
- 1 : 0;
+
+ stopped = SPU_STATUS_INVALID_INSTR | SPU_STATUS_SINGLE_STEP |
+ SPU_STATUS_STOPPED_BY_HALT | SPU_STATUS_STOPPED_BY_STOP;
+ if (*stat & stopped)
+ return 1;
+
+ dsisr = ctx->csa.dsisr;
+ if (dsisr & (MFC_DSISR_PTE_NOT_FOUND | MFC_DSISR_ACCESS_DENIED))
+ return 1;
+
+ if (ctx->csa.class_0_pending)
+ return 1;
+
+ return 0;
}
static int spu_setup_isolated(struct spu_context *ctx)
@@ -151,24 +159,27 @@
static int spu_run_init(struct spu_context *ctx, u32 *npc)
{
- unsigned long runcntl;
+ unsigned long runcntl = SPU_RUNCNTL_RUNNABLE;
int ret;
spuctx_switch_state(ctx, SPU_UTIL_SYSTEM);
- if (ctx->flags & SPU_CREATE_ISOLATE) {
- /*
- * Force activation of spu. Isolated state assumes that
- * special loader context is loaded and running on spu.
- */
+ /*
+ * NOSCHED is synchronous scheduling with respect to the caller.
+ * The caller waits for the context to be loaded.
+ */
+ if (ctx->flags & SPU_CREATE_NOSCHED) {
if (ctx->state == SPU_STATE_SAVED) {
- spu_set_timeslice(ctx);
-
ret = spu_activate(ctx, 0);
if (ret)
return ret;
}
+ }
+ /*
+ * Apply special setup as required.
+ */
+ if (ctx->flags & SPU_CREATE_ISOLATE) {
if (!(ctx->ops->status_read(ctx) & SPU_STATUS_ISOLATED_STATE)) {
ret = spu_setup_isolated(ctx);
if (ret)
@@ -183,10 +194,11 @@
(SPU_RUNCNTL_RUNNABLE | SPU_RUNCNTL_ISOLATE);
if (runcntl == 0)
runcntl = SPU_RUNCNTL_RUNNABLE;
+ }
+ if (ctx->flags & SPU_CREATE_NOSCHED) {
spuctx_switch_state(ctx, SPU_UTIL_USER);
ctx->ops->runcntl_write(ctx, runcntl);
-
} else {
unsigned long privcntl;
@@ -194,20 +206,18 @@
privcntl = SPU_PRIVCNTL_MODE_SINGLE_STEP;
else
privcntl = SPU_PRIVCNTL_MODE_NORMAL;
- runcntl = SPU_RUNCNTL_RUNNABLE;
ctx->ops->npc_write(ctx, *npc);
ctx->ops->privcntl_write(ctx, privcntl);
+ ctx->ops->runcntl_write(ctx, runcntl);
if (ctx->state == SPU_STATE_SAVED) {
- spu_set_timeslice(ctx);
ret = spu_activate(ctx, 0);
if (ret)
return ret;
+ } else {
+ spuctx_switch_state(ctx, SPU_UTIL_USER);
}
-
- spuctx_switch_state(ctx, SPU_UTIL_USER);
- ctx->ops->runcntl_write(ctx, runcntl);
}
return 0;
@@ -218,6 +228,8 @@
{
int ret = 0;
+ spu_del_from_rq(ctx);
+
*status = ctx->ops->status_read(ctx);
*npc = ctx->ops->npc_read(ctx);
@@ -230,26 +242,6 @@
return ret;
}
-static int spu_reacquire_runnable(struct spu_context *ctx, u32 *npc,
- u32 *status)
-{
- int ret;
-
- ret = spu_run_fini(ctx, npc, status);
- if (ret)
- return ret;
-
- if (*status & (SPU_STATUS_STOPPED_BY_STOP | SPU_STATUS_STOPPED_BY_HALT))
- return *status;
-
- ret = spu_acquire_runnable(ctx, 0);
- if (ret)
- return ret;
-
- spuctx_switch_state(ctx, SPU_UTIL_USER);
- return 0;
-}
-
/*
* SPU syscall restarting is tricky because we violate the basic
* assumption that the signal handler is running on the interrupted
@@ -386,17 +378,8 @@
if (ret)
break;
- if (unlikely(ctx->state != SPU_STATE_RUNNABLE)) {
- ret = spu_reacquire_runnable(ctx, npc, &status);
- if (ret)
- goto out2;
- continue;
- }
-
if (signal_pending(current))
ret = -ERESTARTSYS;
-
-
} while (!ret && !(status & (SPU_STATUS_STOPPED_BY_STOP |
SPU_STATUS_STOPPED_BY_HALT |
SPU_STATUS_SINGLE_STEP)));
@@ -411,7 +394,6 @@
ret = spu_run_fini(ctx, npc, &status);
spu_yield(ctx);
-out2:
if ((ret == 0) ||
((ret == -ERESTARTSYS) &&
((status & SPU_STATUS_STOPPED_BY_HALT) ||