[PATCH v12 47/69] perf: use VMA iterator

Liam Howlett
2022-07-20T02:23:02Z

From: "Matthew Wilcox (Oracle)" <willy@infradead.org>

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

Link: https://lkml.kernel.org/r/20220504011345.662299-32-Liam.Howlett@oracle.com
Link: https://lkml.kernel.org/r/20220621204632.3370049-48-Liam.Howlett@oracle.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
kernel/events/core.c | 3 ++-
kernel/events/uprobes.c | 9 ++++++---
2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 80782cddb1da..61ad10862c21 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -10210,8 +10210,9 @@ 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 2eaa327f8158..401bc2d24ce0 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -349,9 +349,10 @@ 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;

@@ -1231,11 +1232,12 @@ 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;

@@ -1983,9 +1985,10 @@ 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;
/*
--
2.35.1