powerpc/process: Add the function flush_tmregs_to_thread

This patch creates a function flush_tmregs_to_thread which
will then be used by subsequent patches in this series. The
function checks for self tracing ptrace interface attempts
while in the TM context and logs appropriate warning message.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anshuman Khandual 2016-07-28 10:57:31 +08:00 committed by Michael Ellerman
parent 0dc696bcf2
commit 8d460f6156
2 changed files with 28 additions and 0 deletions

View File

@ -75,6 +75,14 @@ static inline void disable_kernel_spe(void)
static inline void __giveup_spe(struct task_struct *t) { }
#endif
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
extern void flush_tmregs_to_thread(struct task_struct *);
#else
static inline void flush_tmregs_to_thread(struct task_struct *t)
{
}
#endif
static inline void clear_task_ebb(struct task_struct *t)
{
#ifdef CONFIG_PPC_BOOK3S_64

View File

@ -1074,6 +1074,26 @@ static inline void restore_sprs(struct thread_struct *old_thread,
#endif
}
#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
void flush_tmregs_to_thread(struct task_struct *tsk)
{
/*
* Process self tracing is not yet supported through
* ptrace interface. Ptrace generic code should have
* prevented this from happening in the first place.
* Warn once here with the message, if some how it
* is attempted.
*/
WARN_ONCE(tsk == current,
"Not expecting ptrace on self: TM regs may be incorrect\n");
/*
* If task is not current, it should have been flushed
* already to it's thread_struct during __switch_to().
*/
}
#endif
struct task_struct *__switch_to(struct task_struct *prev,
struct task_struct *new)
{