x86/mm: Change the leave_mm() condition for local TLB flushes

On a remote TLB flush, we leave_mm() if we're TLBSTATE_LAZY.  For a
local flush_tlb_mm_range(), we leave_mm() if !current->mm.  These
are approximately the same condition -- the scheduler sets lazy TLB
mode when switching to a thread with no mm.

I'm about to merge the local and remote flush code, but for ease of
verifying and bisecting the patch, I want the local and remote flush
behavior to match first.  This patch changes the local code to match
the remote code.

Signed-off-by: Andy Lutomirski <[email protected]>
Acked-by: Rik van Riel <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Arjan van de Ven <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Mel Gorman <[email protected]>
Cc: Michal Hocko <[email protected]>
Cc: Nadav Amit <[email protected]>
Cc: Nadav Amit <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rik van Riel <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Signed-off-by: Ingo Molnar <[email protected]>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/mm/tlb.c b/arch/x86/mm/tlb.c
index 776469cc54e0..3143c9a180e5 100644
--- a/arch/x86/mm/tlb.c
+++ b/arch/x86/mm/tlb.c
@@ -311,7 +311,7 @@ void flush_tlb_mm_range(struct mm_struct *mm, unsigned long start,
 		goto out;
 	}
 
-	if (!current->mm) {
+	if (this_cpu_read(cpu_tlbstate.state) != TLBSTATE_OK) {
 		leave_mm(smp_processor_id());
 
 		/* Synchronize with switch_mm. */