[PATCH v2 2/4] mm: make tlb_flush_pending global

From: Minchan Kim
Date: Tue Aug 01 2017 - 01:56:51 EST


Currently, tlb_flush_pending is used only for CONFIG_[NUMA_BALANCING|
COMPACTION] but upcoming patches to solve subtle TLB flush bacting
problem will use it regardless of compaction/numa so this patch
doesn't remove the dependency.

Cc: Nadav Amit <nadav.amit@xxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx>
---
include/linux/mm_types.h | 21 ---------------------
mm/debug.c | 2 --
2 files changed, 23 deletions(-)

diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index c605f2a3a68e..892a7b0196fd 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -487,14 +487,12 @@ struct mm_struct {
/* numa_scan_seq prevents two threads setting pte_numa */
int numa_scan_seq;
#endif
-#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
/*
* An operation with batched TLB flushing is going on. Anything that
* can move process memory needs to flush the TLB when moving a
* PROT_NONE or PROT_NUMA mapped page.
*/
atomic_t tlb_flush_pending;
-#endif
#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
/* See flush_tlb_batched_pending() */
bool tlb_flush_batched;
@@ -528,7 +526,6 @@ extern void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
extern void tlb_finish_mmu(struct mmu_gather *tlb,
unsigned long start, unsigned long end);

-#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
/*
* Memory barriers to keep this state in sync are graciously provided by
* the page table locks, outside of which no page table modifications happen.
@@ -569,24 +566,6 @@ static inline void dec_tlb_flush_pending(struct mm_struct *mm)
smp_mb__before_atomic();
atomic_dec(&mm->tlb_flush_pending);
}
-#else
-static inline bool mm_tlb_flush_pending(struct mm_struct *mm)
-{
- return false;
-}
-
-static inline void init_tlb_flush_pending(struct mm_struct *mm)
-{
-}
-
-static inline void inc_tlb_flush_pending(struct mm_struct *mm)
-{
-}
-
-static inline void dec_tlb_flush_pending(struct mm_struct *mm)
-{
-}
-#endif

struct vm_fault;

diff --git a/mm/debug.c b/mm/debug.c
index d70103bb4731..18a9b15b1e37 100644
--- a/mm/debug.c
+++ b/mm/debug.c
@@ -158,9 +158,7 @@ void dump_mm(const struct mm_struct *mm)
#ifdef CONFIG_NUMA_BALANCING
mm->numa_next_scan, mm->numa_scan_offset, mm->numa_scan_seq,
#endif
-#if defined(CONFIG_NUMA_BALANCING) || defined(CONFIG_COMPACTION)
atomic_read(&mm->tlb_flush_pending),
-#endif
mm->def_flags, &mm->def_flags
);
}
--
2.7.4