dirty_memory_manager: rename {memory_hard_limit,region_group}::notify_relief

It clashes with region_group_reclaimer::notify_relief, which does something
different. Since we plan to merge region_group_reclaimer into
memory_hard_limit and region_group (this can simplify the code), we
need to avoid duplicate function names.

dirty_memory_manager.cc

@@ -156,13 +156,13 @@ bool region_group::reclaimer_can_block() const {
     return _reclaimer.throttle_threshold() != std::numeric_limits<size_t>::max();
 }
 
-void region_group::notify_relief() {
+void region_group::notify_pressure_relieved() {
     _relief.signal();
 }
 
-void memory_hard_limit::notify_relief() {
+void memory_hard_limit::notify_pressure_relieved() {
     if (_subgroup) {
-        _subgroup->notify_relief();
+        _subgroup->notify_pressure_relieved();
     }
 }
 
@@ -191,7 +191,7 @@ void memory_hard_limit::update(ssize_t delta) {
     do_update(this, top_relief, delta);
 
     if (top_relief) {
-        top_relief->notify_relief();
+        top_relief->notify_pressure_relieved();
     }
 }
 
@@ -206,9 +206,9 @@ void region_group::update(ssize_t delta) {
     }
 
     if (top_relief_memory_hard_limit) {
-        top_relief_memory_hard_limit->notify_relief();
+        top_relief_memory_hard_limit->notify_pressure_relieved();
     } else if (top_relief_region_group) {
-        top_relief_region_group->notify_relief();
+        top_relief_region_group->notify_pressure_relieved();
     }
 }
 

dirty_memory_manager.hh

@@ -211,7 +211,7 @@ public:
             , _reclaimer(reclaimer) {
     }
 
-    void notify_relief();
+    void notify_pressure_relieved();
 
     void update(ssize_t delta);
 
@@ -257,7 +257,7 @@ class region_group : public region_listener {
 
     bool reclaimer_can_block() const;
     future<> start_releaser(scheduling_group deferered_work_sg);
-    void notify_relief();
+    void notify_pressure_relieved();
     friend void region_group_binomial_group_sanity_check(const region_group::region_heap& bh);
 private: // from region_listener
     virtual void moved(region* old_address, region* new_address) override;