mm/mmap.c: clean up CONFIG_DEBUG_VM_RB checks

- be consistent in printing the test which failed

- one message was actually wrong (a<b != b>a)

- don't print second bogus warning if browse_rb() failed

Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 6 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 69d4c5199fd8..c9bc285df255 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -368,16 +368,18 @@ static int browse_rb(struct rb_root *root)
                 struct vm_area_struct *vma;
                 vma = rb_entry(nd, struct vm_area_struct, vm_rb);
                 if (vma->vm_start < prev) {
-                        pr_emerg("vm_start %lx prev %lx\n", vma->vm_start, prev);
+                        pr_emerg("vm_start %lx < prev %lx\n",
+                                  vma->vm_start, prev);
                         bug = 1;
                 }
                 if (vma->vm_start < pend) {
-                        pr_emerg("vm_start %lx pend %lx\n", vma->vm_start, pend);
+                        pr_emerg("vm_start %lx < pend %lx\n",
+                                  vma->vm_start, pend);
                         bug = 1;
                 }
                 if (vma->vm_start > vma->vm_end) {
-                        pr_emerg("vm_end %lx < vm_start %lx\n",
-                                vma->vm_end, vma->vm_start);
+                        pr_emerg("vm_start %lx > vm_end %lx\n",
+                                  vma->vm_start, vma->vm_end);
                         bug = 1;
                 }
                 if (vma->rb_subtree_gap != vma_compute_subtree_gap(vma)) {
@@ -419,8 +421,10 @@ static void validate_mm(struct mm_struct *mm)
         int i = 0;
         unsigned long highest_address = 0;
         struct vm_area_struct *vma = mm->mmap;
+
         while (vma) {
                 struct anon_vma_chain *avc;
+
                 vma_lock_anon_vma(vma);
                 list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
                         anon_vma_interval_tree_verify(avc);
@@ -435,12 +439,13 @@ static void validate_mm(struct mm_struct *mm)
         }
         if (highest_address != mm->highest_vm_end) {
                 pr_emerg("mm->highest_vm_end %lx, found %lx\n",
-                       mm->highest_vm_end, highest_address);
+                          mm->highest_vm_end, highest_address);
                 bug = 1;
         }
         i = browse_rb(&mm->mm_rb);
         if (i != mm->map_count) {
-                pr_emerg("map_count %d rb %d\n", mm->map_count, i);
+                if (i != -1)
+                        pr_emerg("map_count %d rb %d\n", mm->map_count, i);
                 bug = 1;
         }
         BUG_ON(bug);