Commit 5f307be1 authored by Peter Zijlstra's avatar Peter Zijlstra Committed by Ingo Molnar

asm-generic/tlb, arch: Provide generic tlb_flush() based on flush_tlb_range()

Provide a generic tlb_flush() implementation that relies on
flush_tlb_range(). This is a little awkward because flush_tlb_range()
assumes a VMA for range invalidation, but we no longer have one.

Audit of all flush_tlb_range() implementations shows only vma->vm_mm
and vma->vm_flags are used, and of the latter only VM_EXEC (I-TLB
invalidates) and VM_HUGETLB (large TLB invalidate) are used.

Therefore, track VM_EXEC and VM_HUGETLB in two more bits, and create a
'fake' VMA.

This allows architectures that have a reasonably efficient
flush_tlb_range() to not require any additional effort.

No change in behavior intended.
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: default avatarWill Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent e7fd28a7
...@@ -27,6 +27,7 @@ static inline void __tlb_remove_table(void *_table) ...@@ -27,6 +27,7 @@ static inline void __tlb_remove_table(void *_table)
free_page_and_swap_cache((struct page *)_table); free_page_and_swap_cache((struct page *)_table);
} }
#define tlb_flush tlb_flush
static void tlb_flush(struct mmu_gather *tlb); static void tlb_flush(struct mmu_gather *tlb);
#include <asm-generic/tlb.h> #include <asm-generic/tlb.h>
......
...@@ -28,6 +28,7 @@ ...@@ -28,6 +28,7 @@
#define tlb_end_vma(tlb, vma) do { } while (0) #define tlb_end_vma(tlb, vma) do { } while (0)
#define __tlb_remove_tlb_entry __tlb_remove_tlb_entry #define __tlb_remove_tlb_entry __tlb_remove_tlb_entry
#define tlb_flush tlb_flush
extern void tlb_flush(struct mmu_gather *tlb); extern void tlb_flush(struct mmu_gather *tlb);
/* Get the generic bits... */ /* Get the generic bits... */
......
...@@ -18,6 +18,7 @@ struct mmu_gather; ...@@ -18,6 +18,7 @@ struct mmu_gather;
static void tlb_flush(struct mmu_gather *tlb); static void tlb_flush(struct mmu_gather *tlb);
#define tlb_flush tlb_flush
#include <asm-generic/tlb.h> #include <asm-generic/tlb.h>
static inline void tlb_flush(struct mmu_gather *tlb) static inline void tlb_flush(struct mmu_gather *tlb)
......
...@@ -6,6 +6,7 @@ ...@@ -6,6 +6,7 @@
#define tlb_end_vma(tlb, vma) do { } while (0) #define tlb_end_vma(tlb, vma) do { } while (0)
#define __tlb_remove_tlb_entry(tlb, ptep, address) do { } while (0) #define __tlb_remove_tlb_entry(tlb, ptep, address) do { } while (0)
#define tlb_flush tlb_flush
static inline void tlb_flush(struct mmu_gather *tlb); static inline void tlb_flush(struct mmu_gather *tlb);
#include <asm-generic/tlb.h> #include <asm-generic/tlb.h>
......
...@@ -95,7 +95,7 @@ ...@@ -95,7 +95,7 @@
* flush the entire TLB irrespective of the range. For instance * flush the entire TLB irrespective of the range. For instance
* x86-PAE needs this when changing top-level entries. * x86-PAE needs this when changing top-level entries.
* *
* And requires the architecture to provide and implement tlb_flush(). * And allows the architecture to provide and implement tlb_flush():
* *
* tlb_flush() may, in addition to the above mentioned mmu_gather fields, make * tlb_flush() may, in addition to the above mentioned mmu_gather fields, make
* use of: * use of:
...@@ -111,7 +111,10 @@ ...@@ -111,7 +111,10 @@
* *
* - tlb_get_unmap_shift() / tlb_get_unmap_size() * - tlb_get_unmap_shift() / tlb_get_unmap_size()
* *
* returns the smallest TLB entry size unmapped in this range * returns the smallest TLB entry size unmapped in this range.
*
* If an architecture does not provide tlb_flush() a default implementation
* based on flush_tlb_range() will be used.
* *
* Additionally there are a few opt-in features: * Additionally there are a few opt-in features:
* *
...@@ -245,6 +248,12 @@ struct mmu_gather { ...@@ -245,6 +248,12 @@ struct mmu_gather {
unsigned int cleared_puds : 1; unsigned int cleared_puds : 1;
unsigned int cleared_p4ds : 1; unsigned int cleared_p4ds : 1;
/*
* tracks VM_EXEC | VM_HUGETLB in tlb_start_vma
*/
unsigned int vma_exec : 1;
unsigned int vma_huge : 1;
unsigned int batch_count; unsigned int batch_count;
struct mmu_gather_batch *active; struct mmu_gather_batch *active;
...@@ -286,8 +295,59 @@ static inline void __tlb_reset_range(struct mmu_gather *tlb) ...@@ -286,8 +295,59 @@ static inline void __tlb_reset_range(struct mmu_gather *tlb)
tlb->cleared_pmds = 0; tlb->cleared_pmds = 0;
tlb->cleared_puds = 0; tlb->cleared_puds = 0;
tlb->cleared_p4ds = 0; tlb->cleared_p4ds = 0;
/*
* Do not reset mmu_gather::vma_* fields here, we do not
* call into tlb_start_vma() again to set them if there is an
* intermediate flush.
*/
}
#ifndef tlb_flush
#if defined(tlb_start_vma) || defined(tlb_end_vma)
#error Default tlb_flush() relies on default tlb_start_vma() and tlb_end_vma()
#endif
static inline void tlb_flush(struct mmu_gather *tlb)
{
if (tlb->fullmm || tlb->need_flush_all) {
flush_tlb_mm(tlb->mm);
} else if (tlb->end) {
struct vm_area_struct vma = {
.vm_mm = tlb->mm,
.vm_flags = (tlb->vma_exec ? VM_EXEC : 0) |
(tlb->vma_huge ? VM_HUGETLB : 0),
};
flush_tlb_range(&vma, tlb->start, tlb->end);
}
}
static inline void
tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma)
{
/*
* flush_tlb_range() implementations that look at VM_HUGETLB (tile,
* mips-4k) flush only large pages.
*
* flush_tlb_range() implementations that flush I-TLB also flush D-TLB
* (tile, xtensa, arm), so it's ok to just add VM_EXEC to an existing
* range.
*
* We rely on tlb_end_vma() to issue a flush, such that when we reset
* these values the batch is empty.
*/
tlb->vma_huge = !!(vma->vm_flags & VM_HUGETLB);
tlb->vma_exec = !!(vma->vm_flags & VM_EXEC);
} }
#else
static inline void
tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) { }
#endif
static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb)
{ {
if (!tlb->end) if (!tlb->end)
...@@ -357,19 +417,30 @@ static inline unsigned long tlb_get_unmap_size(struct mmu_gather *tlb) ...@@ -357,19 +417,30 @@ static inline unsigned long tlb_get_unmap_size(struct mmu_gather *tlb)
* the vmas are adjusted to only cover the region to be torn down. * the vmas are adjusted to only cover the region to be torn down.
*/ */
#ifndef tlb_start_vma #ifndef tlb_start_vma
#define tlb_start_vma(tlb, vma) \ static inline void tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
do { \ {
if (!tlb->fullmm) \ if (tlb->fullmm)
flush_cache_range(vma, vma->vm_start, vma->vm_end); \ return;
} while (0)
tlb_update_vma_flags(tlb, vma);
flush_cache_range(vma, vma->vm_start, vma->vm_end);
}
#endif #endif
#ifndef tlb_end_vma #ifndef tlb_end_vma
#define tlb_end_vma(tlb, vma) \ static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma)
do { \ {
if (!tlb->fullmm) \ if (tlb->fullmm)
tlb_flush_mmu_tlbonly(tlb); \ return;
} while (0)
/*
* Do a TLB flush and reset the range at VMA boundaries; this avoids
* the ranges growing with the unused space between consecutive VMAs,
* but also the mmu_gather::vma_* flags from tlb_start_vma() rely on
* this.
*/
tlb_flush_mmu_tlbonly(tlb);
}
#endif #endif
#ifndef __tlb_remove_tlb_entry #ifndef __tlb_remove_tlb_entry
......
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