From: Kaixu Xia <kaixuxia@xxxxxxxxxxx>
The damon regions that belong to the same damon target have the same
'struct mm_struct *mm', so it's unnecessary to compare the mm and last_mm
objects among the damon regions in one damon target when checking accesses.
But the check is necessary when the target changed in
'__damon_va_check_accesses()', so we can simplify the whole operation by
using the bool 'same_target' to indicate whether the target changed.
Signed-off-by: Kaixu Xia <kaixuxia@xxxxxxxxxxx>
---
mm/damon/vaddr.c | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/mm/damon/vaddr.c b/mm/damon/vaddr.c
index e481f81c3efb..5f66c826ee3a 100644
--- a/mm/damon/vaddr.c
+++ b/mm/damon/vaddr.c
@@ -533,15 +533,14 @@ static bool damon_va_young(struct mm_struct *mm, unsigned long addr,
* r the region to be checked
*/
static void __damon_va_check_access(struct mm_struct *mm,
- struct damon_region *r)
+ struct damon_region *r, bool same_target)
{
- static struct mm_struct *last_mm;
static unsigned long last_addr;
static unsigned long last_page_sz = PAGE_SIZE;
static bool last_accessed;
/* If the region is in the last checked page, reuse the result */
- if (mm == last_mm && (ALIGN_DOWN(last_addr, last_page_sz) ==
+ if (same_target && (ALIGN_DOWN(last_addr, last_page_sz) ==
ALIGN_DOWN(r->sampling_addr, last_page_sz))) {
if (last_accessed)
r->nr_accesses++;
@@ -552,7 +551,6 @@ static void __damon_va_check_access(struct mm_struct *mm,
if (last_accessed)
r->nr_accesses++;
- last_mm = mm;
last_addr = r->sampling_addr;
}
@@ -562,14 +560,17 @@ static unsigned int damon_va_check_accesses(struct damon_ctx *ctx)
struct mm_struct *mm;
struct damon_region *r;
unsigned int max_nr_accesses = 0;
+ bool same_target;
damon_for_each_target(t, ctx) {
mm = damon_get_mm(t);
if (!mm)
continue;
+ same_target = false;
damon_for_each_region(r, t) {
- __damon_va_check_access(mm, r);
+ __damon_va_check_access(mm, r, same_target);
max_nr_accesses = max(r->nr_accesses, max_nr_accesses);
+ same_target = true;
}
mmput(mm);
}
--
2.27.0
