diff options
| author |   Michel Lespinasse <walken@google.com> | 2019-09-25 16:46:07 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-25 17:51:39 -0700 |
| commit | 315cc066b8ae8349a27887ad7a34e1916e9797fe (patch) | |
| tree | 3c7dba850cee3ec6991228ae425db0de78fbb252 /mm/mmap.c | |
| parent | augmented rbtree: add comments for RB_DECLARE_CALLBACKS macro (diff) | |
| download | linux-dev-315cc066b8ae8349a27887ad7a34e1916e9797fe.tar.xz linux-dev-315cc066b8ae8349a27887ad7a34e1916e9797fe.zip | |
augmented rbtree: add new RB_DECLARE_CALLBACKS_MAX macro
Add RB_DECLARE_CALLBACKS_MAX, which generates augmented rbtree callbacks
for the case where the augmented value is a scalar whose definition
follows a max(f(node)) pattern. This actually covers all present uses of
RB_DECLARE_CALLBACKS, and saves some (source) code duplication in the
various RBCOMPUTE function definitions.
[walken@google.com: fix mm/vmalloc.c]
Link: http://lkml.kernel.org/r/CANN689FXgK13wDYNh1zKxdipeTuALG4eKvKpsdZqKFJ-rvtGiQ@mail.gmail.com
[walken@google.com: re-add check to check_augmented()]
Link: http://lkml.kernel.org/r/20190727022027.GA86863@google.com
Link: http://lkml.kernel.org/r/20190703040156.56953-3-walken@google.com
Signed-off-by: Michel Lespinasse <walken@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mmap.c')
| -rw-r--r-- | mm/mmap.c | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index f1e8c7f93e04..14b7da317ec0 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -289,9 +289,9 @@ out: return retval; } -static long vma_compute_subtree_gap(struct vm_area_struct *vma) +static inline unsigned long vma_compute_gap(struct vm_area_struct *vma) { - unsigned long max, prev_end, subtree_gap; + unsigned long gap, prev_end; /* * Note: in the rare case of a VM_GROWSDOWN above a VM_GROWSUP, we @@ -299,14 +299,21 @@ static long vma_compute_subtree_gap(struct vm_area_struct *vma) * an unmapped area; whereas when expanding we only require one. * That's a little inconsistent, but keeps the code here simpler. */ - max = vm_start_gap(vma); + gap = vm_start_gap(vma); if (vma->vm_prev) { prev_end = vm_end_gap(vma->vm_prev); - if (max > prev_end) - max -= prev_end; + if (gap > prev_end) + gap -= prev_end; else - max = 0; + gap = 0; } + return gap; +} + +#ifdef CONFIG_DEBUG_VM_RB +static unsigned long vma_compute_subtree_gap(struct vm_area_struct *vma) +{ + unsigned long max = vma_compute_gap(vma), subtree_gap; if (vma->vm_rb.rb_left) { subtree_gap = rb_entry(vma->vm_rb.rb_left, struct vm_area_struct, vm_rb)->rb_subtree_gap; @@ -322,7 +329,6 @@ static long vma_compute_subtree_gap(struct vm_area_struct *vma) return max; } -#ifdef CONFIG_DEBUG_VM_RB static int browse_rb(struct mm_struct *mm) { struct rb_root *root = &mm->mm_rb; @@ -428,8 +434,9 @@ static void validate_mm(struct mm_struct *mm) #define validate_mm(mm) do { } while (0) #endif -RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb, - unsigned long, rb_subtree_gap, vma_compute_subtree_gap) +RB_DECLARE_CALLBACKS_MAX(static, vma_gap_callbacks, + struct vm_area_struct, vm_rb, + unsigned long, rb_subtree_gap, vma_compute_gap) /* * Update augmented rbtree rb_subtree_gap values after vma->vm_start or @@ -439,8 +446,8 @@ RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb, static void vma_gap_update(struct vm_area_struct *vma) { /* - * As it turns out, RB_DECLARE_CALLBACKS() already created a callback - * function that does exactly what we want. + * As it turns out, RB_DECLARE_CALLBACKS_MAX() already created + * a callback function that does exactly what we want. */ vma_gap_callbacks_propagate(&vma->vm_rb, NULL); } |