We currently set a TIF flag when scheduling out a task that is in
lazy MMU mode, in order to restore it when the task is scheduled
again.

The generic lazy_mmu layer now tracks whether a task is in lazy MMU
mode in task_struct::lazy_mmu_state. We can therefore check that
state when switching to the new task, instead of using a separate
TIF flag.

Signed-off-by: Kevin Brodsky <redacted>
---
  arch/x86/include/asm/thread_info.h | 4 +---
  arch/x86/xen/enlighten_pv.c        | 3 +--
  2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h
index e71e0e8362ed..0067684afb5b 100644
--- a/arch/x86/include/asm/thread_info.h
+++ b/arch/x86/include/asm/thread_info.h

@@ -100,8 +100,7 @@ struct thread_info {
  #define TIF_FORCED_TF		24	/* true if TF in eflags artificially */
  #define TIF_SINGLESTEP		25	/* reenable singlestep on user return*/
  #define TIF_BLOCKSTEP		26	/* set when we want DEBUGCTLMSR_BTF */
-#define TIF_LAZY_MMU_UPDATES	27	/* task is updating the mmu lazily */
-#define TIF_ADDR32		28	/* 32-bit address space on 64 bits */
+#define TIF_ADDR32		27	/* 32-bit address space on 64 bits */
  
  #define _TIF_SSBD		BIT(TIF_SSBD)
  #define _TIF_SPEC_IB		BIT(TIF_SPEC_IB)

@@ -114,7 +113,6 @@ struct thread_info {
  #define _TIF_FORCED_TF		BIT(TIF_FORCED_TF)
  #define _TIF_BLOCKSTEP		BIT(TIF_BLOCKSTEP)
  #define _TIF_SINGLESTEP		BIT(TIF_SINGLESTEP)
-#define _TIF_LAZY_MMU_UPDATES	BIT(TIF_LAZY_MMU_UPDATES)
  #define _TIF_ADDR32		BIT(TIF_ADDR32)
  
  /* flags to check in __switch_to() */

diff --git a/arch/x86/xen/enlighten_pv.c b/arch/x86/xen/enlighten_pv.c
index 4806cc28d7ca..f40f5999352e 100644
--- a/arch/x86/xen/enlighten_pv.c
+++ b/arch/x86/xen/enlighten_pv.c

@@ -426,7 +426,6 @@ static void xen_start_context_switch(struct task_struct *prev)
  
  	if (this_cpu_read(xen_lazy_mode) == XEN_LAZY_MMU) {
  		arch_leave_lazy_mmu_mode();
-		set_ti_thread_flag(task_thread_info(prev), TIF_LAZY_MMU_UPDATES);
  	}
  	enter_lazy(XEN_LAZY_CPU);
  }

@@ -437,7 +436,7 @@ static void xen_end_context_switch(struct task_struct *next)
  
  	xen_mc_flush();
  	leave_lazy(XEN_LAZY_CPU);
-	if (test_and_clear_ti_thread_flag(task_thread_info(next), TIF_LAZY_MMU_UPDATES))
+	if (next->lazy_mmu_state.active)