| Message ID | 20230711202047.3818697-9-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Avoid the mmap lock for fault-around | expand |
On Tue, Jul 11, 2023 at 1:21 PM Matthew Wilcox (Oracle) <willy@infradead.org> wrote: > > Provide lock_vma_under_rcu() when CONFIG_PER_VMA_LOCK is not defined > to eliminate ifdefs in the users. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Very nice. Thanks! Reviewed-by: Suren Baghdasaryan <surenb@google.com> > --- > arch/arm64/mm/fault.c | 2 -- > arch/powerpc/mm/fault.c | 4 ---- > arch/riscv/mm/fault.c | 4 ---- > arch/s390/mm/fault.c | 2 -- > arch/x86/mm/fault.c | 4 ---- > include/linux/mm.h | 6 ++++++ > 6 files changed, 6 insertions(+), 16 deletions(-) > > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c > index b8c80f7b8a5f..2e5d1e238af9 100644 > --- a/arch/arm64/mm/fault.c > +++ b/arch/arm64/mm/fault.c > @@ -587,7 +587,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, > > perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); > > -#ifdef CONFIG_PER_VMA_LOCK > if (!(mm_flags & FAULT_FLAG_USER)) > goto lock_mmap; > > @@ -616,7 +615,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, > return 0; > } > lock_mmap: > -#endif /* CONFIG_PER_VMA_LOCK */ > > retry: > vma = lock_mm_and_find_vma(mm, addr, regs); > diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c > index 82954d0e6906..b1723094d464 100644 > --- a/arch/powerpc/mm/fault.c > +++ b/arch/powerpc/mm/fault.c > @@ -469,7 +469,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, > if (is_exec) > flags |= FAULT_FLAG_INSTRUCTION; > > -#ifdef CONFIG_PER_VMA_LOCK > if (!(flags & FAULT_FLAG_USER)) > goto lock_mmap; > > @@ -502,7 +501,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, > return user_mode(regs) ? 0 : SIGBUS; > > lock_mmap: > -#endif /* CONFIG_PER_VMA_LOCK */ > > /* When running in the kernel we expect faults to occur only to > * addresses in user space. All other faults represent errors in the > @@ -552,9 +550,7 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, > > mmap_read_unlock(current->mm); > > -#ifdef CONFIG_PER_VMA_LOCK > done: > -#endif > if (unlikely(fault & VM_FAULT_ERROR)) > return mm_fault_error(regs, address, fault); > > diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c > index 6ea2cce4cc17..046732fcb48c 100644 > --- a/arch/riscv/mm/fault.c > +++ b/arch/riscv/mm/fault.c > @@ -283,7 +283,6 @@ void handle_page_fault(struct pt_regs *regs) > flags |= FAULT_FLAG_WRITE; > else if (cause == EXC_INST_PAGE_FAULT) > flags |= FAULT_FLAG_INSTRUCTION; > -#ifdef CONFIG_PER_VMA_LOCK > if (!(flags & FAULT_FLAG_USER)) > goto lock_mmap; > > @@ -311,7 +310,6 @@ void handle_page_fault(struct pt_regs *regs) > return; > } > lock_mmap: > -#endif /* CONFIG_PER_VMA_LOCK */ > > retry: > vma = lock_mm_and_find_vma(mm, addr, regs); > @@ -368,9 +366,7 @@ void handle_page_fault(struct pt_regs *regs) > > mmap_read_unlock(mm); > > -#ifdef CONFIG_PER_VMA_LOCK > done: > -#endif > if (unlikely(fault & VM_FAULT_ERROR)) { > tsk->thread.bad_cause = cause; > mm_fault_error(regs, addr, fault); > diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c > index 40a71063949b..ac8351f172bb 100644 > --- a/arch/s390/mm/fault.c > +++ b/arch/s390/mm/fault.c > @@ -407,7 +407,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) > access = VM_WRITE; > if (access == VM_WRITE) > flags |= FAULT_FLAG_WRITE; > -#ifdef CONFIG_PER_VMA_LOCK > if (!(flags & FAULT_FLAG_USER)) > goto lock_mmap; > vma = lock_vma_under_rcu(mm, address); > @@ -431,7 +430,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) > goto out; > } > lock_mmap: > -#endif /* CONFIG_PER_VMA_LOCK */ > mmap_read_lock(mm); > > gmap = NULL; > diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c > index b0f7add07aa5..ab778eac1952 100644 > --- a/arch/x86/mm/fault.c > +++ b/arch/x86/mm/fault.c > @@ -1350,7 +1350,6 @@ void do_user_addr_fault(struct pt_regs *regs, > } > #endif > > -#ifdef CONFIG_PER_VMA_LOCK > if (!(flags & FAULT_FLAG_USER)) > goto lock_mmap; > > @@ -1381,7 +1380,6 @@ void do_user_addr_fault(struct pt_regs *regs, > return; > } > lock_mmap: > -#endif /* CONFIG_PER_VMA_LOCK */ > > retry: > vma = lock_mm_and_find_vma(mm, address, regs); > @@ -1441,9 +1439,7 @@ void do_user_addr_fault(struct pt_regs *regs, > } > > mmap_read_unlock(mm); > -#ifdef CONFIG_PER_VMA_LOCK > done: > -#endif > if (likely(!(fault & VM_FAULT_ERROR))) > return; > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 46c442855df7..3c923a4bf213 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -813,6 +813,12 @@ static inline void assert_fault_locked(struct vm_fault *vmf) > mmap_assert_locked(vmf->vma->vm_mm); > } > > +static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, > + unsigned long address) > +{ > + return NULL; > +} > + > #endif /* CONFIG_PER_VMA_LOCK */ > > /* > -- > 2.39.2 >
diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index b8c80f7b8a5f..2e5d1e238af9 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -587,7 +587,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, addr); -#ifdef CONFIG_PER_VMA_LOCK if (!(mm_flags & FAULT_FLAG_USER)) goto lock_mmap; @@ -616,7 +615,6 @@ static int __kprobes do_page_fault(unsigned long far, unsigned long esr, return 0; } lock_mmap: -#endif /* CONFIG_PER_VMA_LOCK */ retry: vma = lock_mm_and_find_vma(mm, addr, regs); diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index 82954d0e6906..b1723094d464 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -469,7 +469,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, if (is_exec) flags |= FAULT_FLAG_INSTRUCTION; -#ifdef CONFIG_PER_VMA_LOCK if (!(flags & FAULT_FLAG_USER)) goto lock_mmap; @@ -502,7 +501,6 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, return user_mode(regs) ? 0 : SIGBUS; lock_mmap: -#endif /* CONFIG_PER_VMA_LOCK */ /* When running in the kernel we expect faults to occur only to * addresses in user space. All other faults represent errors in the @@ -552,9 +550,7 @@ static int ___do_page_fault(struct pt_regs *regs, unsigned long address, mmap_read_unlock(current->mm); -#ifdef CONFIG_PER_VMA_LOCK done: -#endif if (unlikely(fault & VM_FAULT_ERROR)) return mm_fault_error(regs, address, fault); diff --git a/arch/riscv/mm/fault.c b/arch/riscv/mm/fault.c index 6ea2cce4cc17..046732fcb48c 100644 --- a/arch/riscv/mm/fault.c +++ b/arch/riscv/mm/fault.c @@ -283,7 +283,6 @@ void handle_page_fault(struct pt_regs *regs) flags |= FAULT_FLAG_WRITE; else if (cause == EXC_INST_PAGE_FAULT) flags |= FAULT_FLAG_INSTRUCTION; -#ifdef CONFIG_PER_VMA_LOCK if (!(flags & FAULT_FLAG_USER)) goto lock_mmap; @@ -311,7 +310,6 @@ void handle_page_fault(struct pt_regs *regs) return; } lock_mmap: -#endif /* CONFIG_PER_VMA_LOCK */ retry: vma = lock_mm_and_find_vma(mm, addr, regs); @@ -368,9 +366,7 @@ void handle_page_fault(struct pt_regs *regs) mmap_read_unlock(mm); -#ifdef CONFIG_PER_VMA_LOCK done: -#endif if (unlikely(fault & VM_FAULT_ERROR)) { tsk->thread.bad_cause = cause; mm_fault_error(regs, addr, fault); diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 40a71063949b..ac8351f172bb 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -407,7 +407,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) access = VM_WRITE; if (access == VM_WRITE) flags |= FAULT_FLAG_WRITE; -#ifdef CONFIG_PER_VMA_LOCK if (!(flags & FAULT_FLAG_USER)) goto lock_mmap; vma = lock_vma_under_rcu(mm, address); @@ -431,7 +430,6 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) goto out; } lock_mmap: -#endif /* CONFIG_PER_VMA_LOCK */ mmap_read_lock(mm); gmap = NULL; diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index b0f7add07aa5..ab778eac1952 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -1350,7 +1350,6 @@ void do_user_addr_fault(struct pt_regs *regs, } #endif -#ifdef CONFIG_PER_VMA_LOCK if (!(flags & FAULT_FLAG_USER)) goto lock_mmap; @@ -1381,7 +1380,6 @@ void do_user_addr_fault(struct pt_regs *regs, return; } lock_mmap: -#endif /* CONFIG_PER_VMA_LOCK */ retry: vma = lock_mm_and_find_vma(mm, address, regs); @@ -1441,9 +1439,7 @@ void do_user_addr_fault(struct pt_regs *regs, } mmap_read_unlock(mm); -#ifdef CONFIG_PER_VMA_LOCK done: -#endif if (likely(!(fault & VM_FAULT_ERROR))) return; diff --git a/include/linux/mm.h b/include/linux/mm.h index 46c442855df7..3c923a4bf213 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -813,6 +813,12 @@ static inline void assert_fault_locked(struct vm_fault *vmf) mmap_assert_locked(vmf->vma->vm_mm); } +static inline struct vm_area_struct *lock_vma_under_rcu(struct mm_struct *mm, + unsigned long address) +{ + return NULL; +} + #endif /* CONFIG_PER_VMA_LOCK */ /*
Provide lock_vma_under_rcu() when CONFIG_PER_VMA_LOCK is not defined to eliminate ifdefs in the users. Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> --- arch/arm64/mm/fault.c | 2 -- arch/powerpc/mm/fault.c | 4 ---- arch/riscv/mm/fault.c | 4 ---- arch/s390/mm/fault.c | 2 -- arch/x86/mm/fault.c | 4 ---- include/linux/mm.h | 6 ++++++ 6 files changed, 6 insertions(+), 16 deletions(-)