[v6,49/71] perf: Use VMA iterator

Commit Message

Liam R. Howlett Feb. 15, 2022, 2:43 p.m. UTC

From: "Liam R. Howlett" <[e-mail]>

The VMA iterator is faster than the linked list and removing the linked
list will shrink the vm_area_struct.

Signed-off-by: Matthew Wilcox (Oracle) <[e-mail]>
Signed-off-by: Liam R. Howlett <[e-mail]>
Acked-by: Vlastimil Babka <[e-mail]>
---
 kernel/events/core.c    | 3 ++-
 kernel/events/uprobes.c | 9 ++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

Patch

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 6859229497b1..935e738a5eb6 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10319,8 +10319,9 @@  static void perf_addr_filter_apply(struct perf_addr_filter *filter,
 				   struct perf_addr_filter_range *fr)
 {
 	struct vm_area_struct *vma;
+	VMA_ITERATOR(vmi, mm, 0);
 
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+	for_each_vma(vmi, vma) {
 		if (!vma->vm_file)
 			continue;
 
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 6357c3580d07..5dee6c41f36d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -356,9 +356,10 @@  static bool valid_ref_ctr_vma(struct uprobe *uprobe,
 static struct vm_area_struct *
 find_ref_ctr_vma(struct uprobe *uprobe, struct mm_struct *mm)
 {
+	VMA_ITERATOR(vmi, mm, 0);
 	struct vm_area_struct *tmp;
 
-	for (tmp = mm->mmap; tmp; tmp = tmp->vm_next)
+	for_each_vma(vmi, tmp)
 		if (valid_ref_ctr_vma(uprobe, tmp))
 			return tmp;
 
@@ -1237,11 +1238,12 @@  int uprobe_apply(struct inode *inode, loff_t offset,
 
 static int unapply_uprobe(struct uprobe *uprobe, struct mm_struct *mm)
 {
+	VMA_ITERATOR(vmi, mm, 0);
 	struct vm_area_struct *vma;
 	int err = 0;
 
 	mmap_read_lock(mm);
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+	for_each_vma(vmi, vma) {
 		unsigned long vaddr;
 		loff_t offset;
 
@@ -1989,9 +1991,10 @@  bool uprobe_deny_signal(void)
 
 static void mmf_recalc_uprobes(struct mm_struct *mm)
 {
+	VMA_ITERATOR(vmi, mm, 0);
 	struct vm_area_struct *vma;
 
-	for (vma = mm->mmap; vma; vma = vma->vm_next) {
+	for_each_vma(vmi, vma) {
 		if (!valid_vma(vma, false))
 			continue;
 		/*