powerpc/tm: Drop tm_orig_msr from thread_struct

Currently tm_orig_msr is getting used during process context switch only.
Then there is ckpt_regs which saves the checkpointed userspace context
The MSR slot contained in ckpt_regs structure can be used during process
context switch instead of tm_orig_msr, thus allowing us to drop it from
thread_struct structure. This patch does that change.

Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anshuman Khandual 2015-07-06 16:24:10 +05:30 committed by Michael Ellerman
parent bd664f892e
commit 829023df86
2 changed files with 7 additions and 8 deletions

View File

@ -264,7 +264,6 @@ struct thread_struct {
u64 tm_tfhar; /* Transaction fail handler addr */
u64 tm_texasr; /* Transaction exception & summary */
u64 tm_tfiar; /* Transaction fail instr address reg */
unsigned long tm_orig_msr; /* Thread's MSR on ctx switch */
struct pt_regs ckpt_regs; /* Checkpointed registers */
unsigned long tm_tar;

View File

@ -86,7 +86,7 @@ void giveup_fpu_maybe_transactional(struct task_struct *tsk)
if (tsk == current && tsk->thread.regs &&
MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
!test_thread_flag(TIF_RESTORE_TM)) {
tsk->thread.tm_orig_msr = tsk->thread.regs->msr;
tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
set_thread_flag(TIF_RESTORE_TM);
}
@ -104,7 +104,7 @@ void giveup_altivec_maybe_transactional(struct task_struct *tsk)
if (tsk == current && tsk->thread.regs &&
MSR_TM_ACTIVE(tsk->thread.regs->msr) &&
!test_thread_flag(TIF_RESTORE_TM)) {
tsk->thread.tm_orig_msr = tsk->thread.regs->msr;
tsk->thread.ckpt_regs.msr = tsk->thread.regs->msr;
set_thread_flag(TIF_RESTORE_TM);
}
@ -543,7 +543,7 @@ static void tm_reclaim_thread(struct thread_struct *thr,
* the thread will no longer be transactional.
*/
if (test_ti_thread_flag(ti, TIF_RESTORE_TM)) {
msr_diff = thr->tm_orig_msr & ~thr->regs->msr;
msr_diff = thr->ckpt_regs.msr & ~thr->regs->msr;
if (msr_diff & MSR_FP)
memcpy(&thr->transact_fp, &thr->fp_state,
sizeof(struct thread_fp_state));
@ -594,10 +594,10 @@ static inline void tm_reclaim_task(struct task_struct *tsk)
/* Stash the original thread MSR, as giveup_fpu et al will
* modify it. We hold onto it to see whether the task used
* FP & vector regs. If the TIF_RESTORE_TM flag is set,
* tm_orig_msr is already set.
* ckpt_regs.msr is already set.
*/
if (!test_ti_thread_flag(task_thread_info(tsk), TIF_RESTORE_TM))
thr->tm_orig_msr = thr->regs->msr;
thr->ckpt_regs.msr = thr->regs->msr;
TM_DEBUG("--- tm_reclaim on pid %d (NIP=%lx, "
"ccr=%lx, msr=%lx, trap=%lx)\n",
@ -666,7 +666,7 @@ static inline void tm_recheckpoint_new_task(struct task_struct *new)
tm_restore_sprs(&new->thread);
return;
}
msr = new->thread.tm_orig_msr;
msr = new->thread.ckpt_regs.msr;
/* Recheckpoint to restore original checkpointed register state. */
TM_DEBUG("*** tm_recheckpoint of pid %d "
"(new->msr 0x%lx, new->origmsr 0x%lx)\n",
@ -726,7 +726,7 @@ void restore_tm_state(struct pt_regs *regs)
if (!MSR_TM_ACTIVE(regs->msr))
return;
msr_diff = current->thread.tm_orig_msr & ~regs->msr;
msr_diff = current->thread.ckpt_regs.msr & ~regs->msr;
msr_diff &= MSR_FP | MSR_VEC | MSR_VSX;
if (msr_diff & MSR_FP) {
fp_enable();