Commit 85687ff2 authored Feb 08, 2008 by Luke Browning Committed by Paul Mackerras Feb 08, 2008

[POWERPC] spufs: Fix timing dependent false return from spufs_run_spu

Stop bits are only valid when the running bit is not set. Status bits
carry over from one invocation of spufs_run_spu() to another, so the
RUNNING bit gets added to the previous state of the register which may
have been a remote library call. In this case, it looks like another
library routine should be invoked, but the spe is actually running.

This fixes a problem with a testcase that exercises the scheduler.

Signed-off-by: Luke Browning <lukebrowning@us.ibm.com>
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

parent e66686b4

arch/powerpc/platforms/cell/spufs/run.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -53,7 +53,7 @@ int spu_stopped(struct spu_context ctx, u32 stat)

	stopped = SPU_STATUS_INVALID_INSTR \| SPU_STATUS_SINGLE_STEP \|		stopped = SPU_STATUS_INVALID_INSTR \| SPU_STATUS_SINGLE_STEP \|
	SPU_STATUS_STOPPED_BY_HALT \| SPU_STATUS_STOPPED_BY_STOP;		SPU_STATUS_STOPPED_BY_HALT \| SPU_STATUS_STOPPED_BY_STOP;
	if (*stat & stopped)		if (!(stat & SPU_STATUS_RUNNING) && (stat & stopped))
	return 1;		return 1;

	dsisr = ctx->csa.dsisr;		dsisr = ctx->csa.dsisr;