[PATCH] powerpc: restore current_thread_info()

[Al Viro]

On Tue, May 07, 2019 at 03:51:21PM -0700, Yury Norov wrote:
> Commit ed1cd6deb013 ("powerpc: Activate CONFIG_THREAD_INFO_IN_TASK")
> removes the function current_thread_info(). It's wrong because the
> function is used in non-arch code and is part of API.

In include/linux/thread_info.h:

#ifdef CONFIG_THREAD_INFO_IN_TASK
/*
 * For CONFIG_THREAD_INFO_IN_TASK kernels we need <asm/current.h> for the
 * definition of current, but for !CONFIG_THREAD_INFO_IN_TASK kernels,
 * including <asm/current.h> can cause a circular dependency on some platforms.
 */
#include <asm/current.h>
#define current_thread_info() ((struct thread_info *)current)
#endif