On Tue, Apr 09, 2013 at 01:33:34PM +0100, Christopher Covington wrote: > For accurate accounting pass contextidr_thread_switch the prev > task pointer, since cpu_switch_to has at that point changed the > the stack pointer. > > Signed-off-by: Christopher Covington <c...@codeaurora.org> > --- > arch/arm64/kernel/process.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c > index 0337cdb..a49b25a 100644 > --- a/arch/arm64/kernel/process.c > +++ b/arch/arm64/kernel/process.c > @@ -315,7 +315,7 @@ struct task_struct *__switch_to(struct task_struct *prev, > /* the actual thread switch */ > last = cpu_switch_to(prev, next); > > - contextidr_thread_switch(next); > + contextidr_thread_switch(prev);
The original code was indeed wrong but using prev isn't any better. For a newly created thread, prev is probably 0 (if it's in a register, cpu_context has been zeroed by copy_thread()) or some random stack value. So we either use current or move the call before cpu_switch_to() (I would go for the former). -- Catalin -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
