summaryrefslogtreecommitdiff
path: root/mm/vmpressure.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2016-03-25 03:53:42 -0300
commit03dd4cb26d967f9588437b0fc9cc0e8353322bb7 (patch)
treefa581f6dc1c0596391690d1f67eceef3af8246dc /mm/vmpressure.c
parentd4e493caf788ef44982e131ff9c786546904d934 (diff)
Linux-libre 4.5-gnu
Diffstat (limited to 'mm/vmpressure.c')
-rw-r--r--mm/vmpressure.c77
1 files changed, 58 insertions, 19 deletions
diff --git a/mm/vmpressure.c b/mm/vmpressure.c
index c5afd573d..149fdf6c5 100644
--- a/mm/vmpressure.c
+++ b/mm/vmpressure.c
@@ -137,14 +137,11 @@ struct vmpressure_event {
};
static bool vmpressure_event(struct vmpressure *vmpr,
- unsigned long scanned, unsigned long reclaimed)
+ enum vmpressure_levels level)
{
struct vmpressure_event *ev;
- enum vmpressure_levels level;
bool signalled = false;
- level = vmpressure_calc_level(scanned, reclaimed);
-
mutex_lock(&vmpr->events_lock);
list_for_each_entry(ev, &vmpr->events, node) {
@@ -164,6 +161,7 @@ static void vmpressure_work_fn(struct work_struct *work)
struct vmpressure *vmpr = work_to_vmpressure(work);
unsigned long scanned;
unsigned long reclaimed;
+ enum vmpressure_levels level;
spin_lock(&vmpr->sr_lock);
/*
@@ -174,19 +172,21 @@ static void vmpressure_work_fn(struct work_struct *work)
* here. No need for any locks here since we don't care if
* vmpr->reclaimed is in sync.
*/
- scanned = vmpr->scanned;
+ scanned = vmpr->tree_scanned;
if (!scanned) {
spin_unlock(&vmpr->sr_lock);
return;
}
- reclaimed = vmpr->reclaimed;
- vmpr->scanned = 0;
- vmpr->reclaimed = 0;
+ reclaimed = vmpr->tree_reclaimed;
+ vmpr->tree_scanned = 0;
+ vmpr->tree_reclaimed = 0;
spin_unlock(&vmpr->sr_lock);
+ level = vmpressure_calc_level(scanned, reclaimed);
+
do {
- if (vmpressure_event(vmpr, scanned, reclaimed))
+ if (vmpressure_event(vmpr, level))
break;
/*
* If not handled, propagate the event upward into the
@@ -199,6 +199,7 @@ static void vmpressure_work_fn(struct work_struct *work)
* vmpressure() - Account memory pressure through scanned/reclaimed ratio
* @gfp: reclaimer's gfp mask
* @memcg: cgroup memory controller handle
+ * @tree: legacy subtree mode
* @scanned: number of pages scanned
* @reclaimed: number of pages reclaimed
*
@@ -206,9 +207,16 @@ static void vmpressure_work_fn(struct work_struct *work)
* "instantaneous" memory pressure (scanned/reclaimed ratio). The raw
* pressure index is then further refined and averaged over time.
*
+ * If @tree is set, vmpressure is in traditional userspace reporting
+ * mode: @memcg is considered the pressure root and userspace is
+ * notified of the entire subtree's reclaim efficiency.
+ *
+ * If @tree is not set, reclaim efficiency is recorded for @memcg, and
+ * only in-kernel users are notified.
+ *
* This function does not return any value.
*/
-void vmpressure(gfp_t gfp, struct mem_cgroup *memcg,
+void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
unsigned long scanned, unsigned long reclaimed)
{
struct vmpressure *vmpr = memcg_to_vmpressure(memcg);
@@ -238,15 +246,46 @@ void vmpressure(gfp_t gfp, struct mem_cgroup *memcg,
if (!scanned)
return;
- spin_lock(&vmpr->sr_lock);
- vmpr->scanned += scanned;
- vmpr->reclaimed += reclaimed;
- scanned = vmpr->scanned;
- spin_unlock(&vmpr->sr_lock);
+ if (tree) {
+ spin_lock(&vmpr->sr_lock);
+ scanned = vmpr->tree_scanned += scanned;
+ vmpr->tree_reclaimed += reclaimed;
+ spin_unlock(&vmpr->sr_lock);
- if (scanned < vmpressure_win)
- return;
- schedule_work(&vmpr->work);
+ if (scanned < vmpressure_win)
+ return;
+ schedule_work(&vmpr->work);
+ } else {
+ enum vmpressure_levels level;
+
+ /* For now, no users for root-level efficiency */
+ if (!memcg || memcg == root_mem_cgroup)
+ return;
+
+ spin_lock(&vmpr->sr_lock);
+ scanned = vmpr->scanned += scanned;
+ reclaimed = vmpr->reclaimed += reclaimed;
+ if (scanned < vmpressure_win) {
+ spin_unlock(&vmpr->sr_lock);
+ return;
+ }
+ vmpr->scanned = vmpr->reclaimed = 0;
+ spin_unlock(&vmpr->sr_lock);
+
+ level = vmpressure_calc_level(scanned, reclaimed);
+
+ if (level > VMPRESSURE_LOW) {
+ /*
+ * Let the socket buffer allocator know that
+ * we are having trouble reclaiming LRU pages.
+ *
+ * For hysteresis keep the pressure state
+ * asserted for a second in which subsequent
+ * pressure events can occur.
+ */
+ memcg->socket_pressure = jiffies + HZ;
+ }
+ }
}
/**
@@ -276,7 +315,7 @@ void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio)
* to the vmpressure() basically means that we signal 'critical'
* level.
*/
- vmpressure(gfp, memcg, vmpressure_win, 0);
+ vmpressure(gfp, memcg, true, vmpressure_win, 0);
}
/**