path: root/mm/mmap.c
diff options
authorWill Deacon <will@kernel.org>2021-01-27 23:53:44 +0000
committerPeter Zijlstra <peterz@infradead.org>2021-01-29 20:02:29 +0100
commitd8b450530b90f8845ab962af18b8a10ed77fc889 (patch)
tree5399ddb38a5f0a743c07866a32bec5ce46175b61 /mm/mmap.c
parenttlb: mmu_gather: Remove unused start/end arguments from tlb_finish_mmu() (diff)
tlb: mmu_gather: Introduce tlb_gather_mmu_fullmm()
Passing the range '0, -1' to tlb_gather_mmu() sets the 'fullmm' flag, which indicates that the mm_struct being operated on is going away. In this case, some architectures (such as arm64) can elide TLB invalidation by ensuring that the TLB tag (ASID) associated with this mm is not immediately reclaimed. Although this behaviour is documented in asm-generic/tlb.h, it's subtle and easily missed. Introduce tlb_gather_mmu_fullmm() to make it clearer that this is for the entire mm and WARN() if tlb_gather_mmu() is called with the 'fullmm' address range. Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Yu Zhao <yuzhao@google.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Link: https://lkml.kernel.org/r/20210127235347.1402-4-will@kernel.org
Diffstat (limited to 'mm/mmap.c')
1 files changed, 1 insertions, 1 deletions
diff --git a/mm/mmap.c b/mm/mmap.c
index 7a9f493a4b83..4eac7c63edbe 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -3214,7 +3214,7 @@ void exit_mmap(struct mm_struct *mm)
- tlb_gather_mmu(&tlb, mm, 0, -1);
+ tlb_gather_mmu_fullmm(&tlb, mm);
/* update_hiwater_rss(mm) here? but nobody should be looking */
/* Use -1 here to ensure all VMAs in the mm are unmapped */
unmap_vmas(&tlb, vma, 0, -1);