From 6b0b50b0617fad5f2af3b928596a25f7de8dbf50 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 5 Jun 2013 17:14:02 -0700 Subject: mm/THP: add pmd args to pgtable deposit and withdraw APIs This will be later used by powerpc THP support. In powerpc we want to use pgtable for storing the hash index values. So instead of adding them to mm_context list, we would like to store them in the second half of pmd Signed-off-by: Aneesh Kumar K.V Reviewed-by: Andrea Arcangeli Reviewed-by: David Gibson Cc: Benjamin Herrenschmidt Signed-off-by: Andrew Morton Signed-off-by: Benjamin Herrenschmidt --- include/asm-generic/pgtable.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include/asm-generic/pgtable.h') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index a59ff51b0166..18e27c210716 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -173,11 +173,12 @@ extern void pmdp_splitting_flush(struct vm_area_struct *vma, #endif #ifndef __HAVE_ARCH_PGTABLE_DEPOSIT -extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pgtable_t pgtable); +extern void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp, + pgtable_t pgtable); #endif #ifndef __HAVE_ARCH_PGTABLE_WITHDRAW -extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm); +extern pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp); #endif #ifndef __HAVE_ARCH_PMDP_INVALIDATE -- cgit v1.2.3 From 40d158e61840fbbe23be3f37302a3ca237c15491 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 11 May 2013 12:13:10 -0400 Subject: consolidate io_remap_pfn_range definitions Signed-off-by: Al Viro --- include/asm-generic/pgtable.h | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'include/asm-generic/pgtable.h') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index a59ff51b0166..b1836987d506 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -692,4 +692,8 @@ static inline pmd_t pmd_mknuma(pmd_t pmd) #endif /* !__ASSEMBLY__ */ +#ifndef io_remap_pfn_range +#define io_remap_pfn_range remap_pfn_range +#endif + #endif /* _ASM_GENERIC_PGTABLE_H */ -- cgit v1.2.3 From 0f8975ec4db2c8b5bd111b211292ca9be0feb6b8 Mon Sep 17 00:00:00 2001 From: Pavel Emelyanov Date: Wed, 3 Jul 2013 15:01:20 -0700 Subject: mm: soft-dirty bits for user memory changes tracking The soft-dirty is a bit on a PTE which helps to track which pages a task writes to. In order to do this tracking one should 1. Clear soft-dirty bits from PTEs ("echo 4 > /proc/PID/clear_refs) 2. Wait some time. 3. Read soft-dirty bits (55'th in /proc/PID/pagemap2 entries) To do this tracking, the writable bit is cleared from PTEs when the soft-dirty bit is. Thus, after this, when the task tries to modify a page at some virtual address the #PF occurs and the kernel sets the soft-dirty bit on the respective PTE. Note, that although all the task's address space is marked as r/o after the soft-dirty bits clear, the #PF-s that occur after that are processed fast. This is so, since the pages are still mapped to physical memory, and thus all the kernel does is finds this fact out and puts back writable, dirty and soft-dirty bits on the PTE. Another thing to note, is that when mremap moves PTEs they are marked with soft-dirty as well, since from the user perspective mremap modifies the virtual memory at mremap's new address. Signed-off-by: Pavel Emelyanov Cc: Matt Mackall Cc: Xiao Guangrong Cc: Glauber Costa Cc: Marcelo Tosatti Cc: KOSAKI Motohiro Cc: Stephen Rothwell Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'include/asm-generic/pgtable.h') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index b1836987d506..a7126d28f4cf 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -396,6 +396,28 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm, #define arch_start_context_switch(prev) do {} while (0) #endif +#ifndef CONFIG_HAVE_ARCH_SOFT_DIRTY +static inline int pte_soft_dirty(pte_t pte) +{ + return 0; +} + +static inline int pmd_soft_dirty(pmd_t pmd) +{ + return 0; +} + +static inline pte_t pte_mksoft_dirty(pte_t pte) +{ + return pte; +} + +static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) +{ + return pmd; +} +#endif + #ifndef __HAVE_PFNMAP_TRACKING /* * Interfaces that can be used by architecture code to keep track of -- cgit v1.2.3 From 179ef71cbc085252e3fe6b8159263a7ed1d88ea4 Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Tue, 13 Aug 2013 16:00:49 -0700 Subject: mm: save soft-dirty bits on swapped pages Andy Lutomirski reported that if a page with _PAGE_SOFT_DIRTY bit set get swapped out, the bit is getting lost and no longer available when pte read back. To resolve this we introduce _PTE_SWP_SOFT_DIRTY bit which is saved in pte entry for the page being swapped out. When such page is to be read back from a swap cache we check for bit presence and if it's there we clear it and restore the former _PAGE_SOFT_DIRTY bit back. One of the problem was to find a place in pte entry where we can save the _PTE_SWP_SOFT_DIRTY bit while page is in swap. The _PAGE_PSE was chosen for that, it doesn't intersect with swap entry format stored in pte. Reported-by: Andy Lutomirski Signed-off-by: Cyrill Gorcunov Acked-by: Pavel Emelyanov Cc: Matt Mackall Cc: Xiao Guangrong Cc: Marcelo Tosatti Cc: KOSAKI Motohiro Cc: Stephen Rothwell Cc: Peter Zijlstra Cc: "Aneesh Kumar K.V" Reviewed-by: Minchan Kim Reviewed-by: Wanpeng Li Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/asm-generic/pgtable.h') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 2f47ade1b567..2a7e0d10ad9a 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -417,6 +417,21 @@ static inline pmd_t pmd_mksoft_dirty(pmd_t pmd) { return pmd; } + +static inline pte_t pte_swp_mksoft_dirty(pte_t pte) +{ + return pte; +} + +static inline int pte_swp_soft_dirty(pte_t pte) +{ + return 0; +} + +static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) +{ + return pte; +} #endif #ifndef __HAVE_PFNMAP_TRACKING -- cgit v1.2.3 From 41bb3476b361ef38576cf9d539b19bae2ac93167 Mon Sep 17 00:00:00 2001 From: Cyrill Gorcunov Date: Tue, 13 Aug 2013 16:00:51 -0700 Subject: mm: save soft-dirty bits on file pages Andy reported that if file page get reclaimed we lose the soft-dirty bit if it was there, so save _PAGE_BIT_SOFT_DIRTY bit when page address get encoded into pte entry. Thus when #pf happens on such non-present pte we can restore it back. Reported-by: Andy Lutomirski Signed-off-by: Cyrill Gorcunov Acked-by: Pavel Emelyanov Cc: Matt Mackall Cc: Xiao Guangrong Cc: Marcelo Tosatti Cc: KOSAKI Motohiro Cc: Stephen Rothwell Cc: Peter Zijlstra Cc: "Aneesh Kumar K.V" Cc: Minchan Kim Cc: Wanpeng Li Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-generic/pgtable.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'include/asm-generic/pgtable.h') diff --git a/include/asm-generic/pgtable.h b/include/asm-generic/pgtable.h index 2a7e0d10ad9a..0807ddf97b05 100644 --- a/include/asm-generic/pgtable.h +++ b/include/asm-generic/pgtable.h @@ -432,6 +432,21 @@ static inline pte_t pte_swp_clear_soft_dirty(pte_t pte) { return pte; } + +static inline pte_t pte_file_clear_soft_dirty(pte_t pte) +{ + return pte; +} + +static inline pte_t pte_file_mksoft_dirty(pte_t pte) +{ + return pte; +} + +static inline int pte_file_soft_dirty(pte_t pte) +{ + return 0; +} #endif #ifndef __HAVE_PFNMAP_TRACKING -- cgit v1.2.3