From 90794bf19dc19691a16b71bcd75c04094d9e392d Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Wed, 22 Feb 2017 15:42:37 -0800 Subject: [PATCH] userfaultfd: non-cooperative: optimize mremap_userfaultfd_complete() Optimize the mremap_userfaultfd_complete() interface to pass only the vm_userfaultfd_ctx pointer through the stack as a microoptimization. Link: http://lkml.kernel.org/r/20161216144821.5183-13-aarcange@redhat.com Signed-off-by: Andrea Arcangeli Reported-by: Hillf Danton Acked-by: Mike Rapoport Cc: "Dr. David Alan Gilbert" Cc: Michael Rapoport Cc: Mike Kravetz Cc: Pavel Emelyanov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/userfaultfd.c | 4 ++-- include/linux/userfaultfd_k.h | 4 ++-- mm/mremap.c | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index 68f978beefac..5d37c37854b0 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -608,11 +608,11 @@ void mremap_userfaultfd_prep(struct vm_area_struct *vma, } } -void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx vm_ctx, +void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx *vm_ctx, unsigned long from, unsigned long to, unsigned long len) { - struct userfaultfd_ctx *ctx = vm_ctx.ctx; + struct userfaultfd_ctx *ctx = vm_ctx->ctx; struct userfaultfd_wait_queue ewq; if (!ctx) diff --git a/include/linux/userfaultfd_k.h b/include/linux/userfaultfd_k.h index 7f318a46044b..78ec197e8b47 100644 --- a/include/linux/userfaultfd_k.h +++ b/include/linux/userfaultfd_k.h @@ -57,7 +57,7 @@ extern void dup_userfaultfd_complete(struct list_head *); extern void mremap_userfaultfd_prep(struct vm_area_struct *, struct vm_userfaultfd_ctx *); -extern void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx, +extern void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx *, unsigned long from, unsigned long to, unsigned long len); @@ -100,7 +100,7 @@ static inline void mremap_userfaultfd_prep(struct vm_area_struct *vma, { } -static inline void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx ctx, +static inline void mremap_userfaultfd_complete(struct vm_userfaultfd_ctx *ctx, unsigned long from, unsigned long to, unsigned long len) diff --git a/mm/mremap.c b/mm/mremap.c index 504b560c013c..8779928d6a70 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -608,6 +608,6 @@ out: up_write(¤t->mm->mmap_sem); if (locked && new_len > old_len) mm_populate(new_addr + old_len, new_len - old_len); - mremap_userfaultfd_complete(uf, addr, new_addr, old_len); + mremap_userfaultfd_complete(&uf, addr, new_addr, old_len); return ret; } -- 2.39.5