[PATCH v4 1/6] asm-generic/tlb: Track freeing of page-table directories in struct mmu_gather
From: Santosh Sivaraj <hidden>
Date: 2020-05-20 08:33:11
Also in:
stable
Subsystem:
generic include/asm header files, mmu gather and tlb invalidation, the rest · Maintainers:
Arnd Bergmann, Will Deacon, "Aneesh Kumar K.V", Andrew Morton, Nick Piggin, Peter Zijlstra, Linus Torvalds
From: Peter Zijlstra <peterz@infradead.org> commit 22a61c3c4f1379ef8b0ce0d5cb78baf3178950e2 upstream Some architectures require different TLB invalidation instructions depending on whether it is only the last-level of page table being changed, or whether there are also changes to the intermediate (directory) entries higher up the tree. Add a new bit to the flags bitfield in struct mmu_gather so that the architecture code can operate accordingly if it's the intermediate levels being invalidated. Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Will Deacon <redacted> Cc: <redacted> # 4.19 Signed-off-by: Santosh Sivaraj <redacted> [santosh: prerequisite for tlbflush backports] --- include/asm-generic/tlb.h | 31 +++++++++++++++++++++++-------- 1 file changed, 23 insertions(+), 8 deletions(-)
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
index b3353e21f3b3..97306b32d8d2 100644
--- a/include/asm-generic/tlb.h
+++ b/include/asm-generic/tlb.h@@ -97,12 +97,22 @@ struct mmu_gather { #endif unsigned long start; unsigned long end; - /* we are in the middle of an operation to clear - * a full mm and can make some optimizations */ - unsigned int fullmm : 1, - /* we have performed an operation which - * requires a complete flush of the tlb */ - need_flush_all : 1; + /* + * we are in the middle of an operation to clear + * a full mm and can make some optimizations + */ + unsigned int fullmm : 1; + + /* + * we have performed an operation which + * requires a complete flush of the tlb + */ + unsigned int need_flush_all : 1; + + /* + * we have removed page directories + */ + unsigned int freed_tables : 1; struct mmu_gather_batch *active; struct mmu_gather_batch local;
@@ -137,6 +147,7 @@ static inline void __tlb_reset_range(struct mmu_gather *tlb) tlb->start = TASK_SIZE; tlb->end = 0; } + tlb->freed_tables = 0; } static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
@@ -278,6 +289,7 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, #define pte_free_tlb(tlb, ptep, address) \ do { \ __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + tlb->freed_tables = 1; \ __pte_free_tlb(tlb, ptep, address); \ } while (0) #endif
@@ -285,7 +297,8 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, #ifndef pmd_free_tlb #define pmd_free_tlb(tlb, pmdp, address) \ do { \ - __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + tlb->freed_tables = 1; \ __pmd_free_tlb(tlb, pmdp, address); \ } while (0) #endif
@@ -295,6 +308,7 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, #define pud_free_tlb(tlb, pudp, address) \ do { \ __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + tlb->freed_tables = 1; \ __pud_free_tlb(tlb, pudp, address); \ } while (0) #endif
@@ -304,7 +318,8 @@ static inline void tlb_remove_check_page_size_change(struct mmu_gather *tlb, #ifndef p4d_free_tlb #define p4d_free_tlb(tlb, pudp, address) \ do { \ - __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + __tlb_adjust_range(tlb, address, PAGE_SIZE); \ + tlb->freed_tables = 1; \ __p4d_free_tlb(tlb, pudp, address); \ } while (0) #endif
--
2.25.4