[RFC PATCH 6/7] pass gfp mask of the allocation that waked kswapd to track number of pages scanned on behalf of each alloc type
From: kaiyang2
Date: Tue Mar 19 2024 - 22:43:44 EST
From: Kaiyang Zhao <kaiyang2@xxxxxxxxxx>
In preparation for exporting the number of pages scanned for each alloc
type
Signed-off-by: Kaiyang Zhao <zh_kaiyang@xxxxxxxxxxx>
---
include/linux/mmzone.h | 1 +
mm/vmscan.c | 13 +++++++++++--
2 files changed, 12 insertions(+), 2 deletions(-)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index a4889c9d4055..abc9f1623c82 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -1288,6 +1288,7 @@ typedef struct pglist_data {
struct task_struct *kswapd; /* Protected by kswapd_lock */
int kswapd_order;
enum zone_type kswapd_highest_zoneidx;
+ gfp_t kswapd_gfp;
int kswapd_failures; /* Number of 'reclaimed == 0' runs */
diff --git a/mm/vmscan.c b/mm/vmscan.c
index aa21da983804..ed0f47e2e810 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -7330,7 +7330,7 @@ clear_reclaim_active(pg_data_t *pgdat, int highest_zoneidx)
* or lower is eligible for reclaim until at least one usable zone is
* balanced.
*/
-static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)
+static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx, gfp_t gfp_mask)
{
int i;
unsigned long nr_soft_reclaimed;
@@ -7345,6 +7345,8 @@ static int balance_pgdat(pg_data_t *pgdat, int order, int highest_zoneidx)
.order = order,
.may_unmap = 1,
};
+ if (is_migrate_movable(gfp_migratetype(gfp_mask)))
+ sc.gfp_mask |= __GFP_MOVABLE;
set_task_reclaim_state(current, &sc.reclaim_state);
psi_memstall_enter(&pflags);
@@ -7659,6 +7661,7 @@ static int kswapd(void *p)
pg_data_t *pgdat = (pg_data_t *)p;
struct task_struct *tsk = current;
const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id);
+ gfp_t gfp_mask;
if (!cpumask_empty(cpumask))
set_cpus_allowed_ptr(tsk, cpumask);
@@ -7680,6 +7683,7 @@ static int kswapd(void *p)
WRITE_ONCE(pgdat->kswapd_order, 0);
WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);
+ WRITE_ONCE(pgdat->kswapd_gfp, 0);
atomic_set(&pgdat->nr_writeback_throttled, 0);
for ( ; ; ) {
bool ret;
@@ -7687,6 +7691,7 @@ static int kswapd(void *p)
alloc_order = reclaim_order = READ_ONCE(pgdat->kswapd_order);
highest_zoneidx = kswapd_highest_zoneidx(pgdat,
highest_zoneidx);
+ gfp_mask = READ_ONCE(pgdat->kswapd_gfp);
kswapd_try_sleep:
kswapd_try_to_sleep(pgdat, alloc_order, reclaim_order,
@@ -7696,8 +7701,10 @@ static int kswapd(void *p)
alloc_order = READ_ONCE(pgdat->kswapd_order);
highest_zoneidx = kswapd_highest_zoneidx(pgdat,
highest_zoneidx);
+ gfp_mask = READ_ONCE(pgdat->kswapd_gfp);
WRITE_ONCE(pgdat->kswapd_order, 0);
WRITE_ONCE(pgdat->kswapd_highest_zoneidx, MAX_NR_ZONES);
+ WRITE_ONCE(pgdat->kswapd_gfp, 0);
ret = try_to_freeze();
if (kthread_should_stop())
@@ -7721,7 +7728,7 @@ static int kswapd(void *p)
trace_mm_vmscan_kswapd_wake(pgdat->node_id, highest_zoneidx,
alloc_order);
reclaim_order = balance_pgdat(pgdat, alloc_order,
- highest_zoneidx);
+ highest_zoneidx, gfp_mask);
if (reclaim_order < alloc_order)
goto kswapd_try_sleep;
}
@@ -7759,6 +7766,8 @@ void wakeup_kswapd(struct zone *zone, gfp_t gfp_flags, int order,
if (READ_ONCE(pgdat->kswapd_order) < order)
WRITE_ONCE(pgdat->kswapd_order, order);
+ WRITE_ONCE(pgdat->kswapd_gfp, gfp_flags);
+
if (!waitqueue_active(&pgdat->kswapd_wait))
return;
--
2.40.1