diff --git a/course/lib.php b/course/lib.php
index f98e9b3f884..e088d7d229c 100644
--- a/course/lib.php
+++ b/course/lib.php
@@ -1376,22 +1376,28 @@ function set_section_visible($courseid, $sectionnumber, $visibility) {
 function get_print_section_cm_text(cm_info $cm, $course) {
     global $OUTPUT;
 
-    // Get course context
-    $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
-
     // Get content from modinfo if specified. Content displays either
     // in addition to the standard link (below), or replaces it if
     // the link is turned off by setting ->url to null.
     if (($content = $cm->get_content()) !== '') {
+        // Improve filter performance by preloading filter setttings for all
+        // activities on the course (this does nothing if called multiple
+        // times)
+        filter_preload_activities($cm->get_modinfo());
+
+        // Get module context
+        $modulecontext = get_context_instance(CONTEXT_MODULE, $cm->id);
         $labelformatoptions = new stdClass();
         $labelformatoptions->noclean = true;
         $labelformatoptions->overflowdiv = true;
-        $labelformatoptions->context = $coursecontext;
+        $labelformatoptions->context = $modulecontext;
         $content = format_text($content, FORMAT_HTML, $labelformatoptions);
     } else {
         $content = '';
     }
 
+    // Get course context
+    $coursecontext = get_context_instance(CONTEXT_COURSE, $course->id);
     $stringoptions = new stdClass;
     $stringoptions->context = $coursecontext;
     $instancename = format_string($cm->name, true,  $stringoptions);
diff --git a/lib/filterlib.php b/lib/filterlib.php
index 73ddf0b342e..7dd5b939f31 100644
--- a/lib/filterlib.php
+++ b/lib/filterlib.php
@@ -816,7 +816,15 @@ function filter_get_all_local_settings($contextid) {
  *      array('filter/tex' => array(), 'mod/glossary' => array('glossaryid', 123))
  */
 function filter_get_active_in_context($context) {
-    global $DB;
+    global $DB, $FILTERLIB_PRIVATE;
+
+    // Use cache (this is a within-request cache only) if available. See
+    // function filter_preload_activities.
+    if (isset($FILTERLIB_PRIVATE->active) &&
+            array_key_exists($context->id, $FILTERLIB_PRIVATE->active)) {
+        return $FILTERLIB_PRIVATE->active[$context->id];
+    }
+
     $contextids = str_replace('/', ',', trim($context->path, '/'));
 
     // The following SQL is tricky. It is explained on
@@ -850,6 +858,129 @@ function filter_get_active_in_context($context) {
     return $filters;
 }
 
+/**
+ * Preloads the list of active filters for all activities (modules) on the course
+ * using two database queries.
+ * @param course_modinfo $modinfo Course object from get_fast_modinfo
+ */
+function filter_preload_activities(course_modinfo $modinfo) {
+    global $DB, $FILTERLIB_PRIVATE;
+
+    // Don't repeat preload
+    if (!isset($FILTERLIB_PRIVATE->preloaded)) {
+        $FILTERLIB_PRIVATE->preloaded = array();
+    }
+    if (!empty($FILTERLIB_PRIVATE->preloaded[$modinfo->get_course_id()])) {
+        return;
+    }
+    $FILTERLIB_PRIVATE->preloaded[$modinfo->get_course_id()] = true;
+
+    // Get contexts for all CMs
+    $cmcontexts = array();
+    $cmcontextids = array();
+    foreach ($modinfo->get_cms() as $cm) {
+        $modulecontext = get_context_instance(CONTEXT_MODULE, $cm->id);
+        $cmcontextids[] = $modulecontext->id;
+        $cmcontexts[] = $modulecontext;
+    }
+
+    // Get course context and all other parents...
+    $coursecontext = get_context_instance(CONTEXT_COURSE, $modinfo->get_course_id());
+    $parentcontextids = explode('/', substr($coursecontext->path, 1));
+    $allcontextids = array_merge($cmcontextids, $parentcontextids);
+
+    // Get all filter_active rows relating to all these contexts
+    list ($sql, $params) = $DB->get_in_or_equal($allcontextids);
+    $filteractives = $DB->get_records_select('filter_active', "contextid $sql", $params);
+
+    // Get all filter_config only for the cm contexts
+    list ($sql, $params) = $DB->get_in_or_equal($cmcontextids);
+    $filterconfigs = $DB->get_records_select('filter_config', "contextid $sql", $params);
+
+    // Note: I was a bit surprised that filter_config only works for the
+    // most specific context (i.e. it does not need to be checked for course
+    // context if we only care about CMs) however basede on code in
+    // filter_get_active_in_context, this does seem to be correct.
+
+    // Build course default active list. Initially this will be an array of
+    // filter name => active score (where an active score >0 means it's active)
+    $courseactive = array();
+
+    // Also build list of filter_active rows below course level, by contextid
+    $remainingactives = array();
+
+    // Array lists filters that are banned at top level
+    $banned = array();
+
+    // Add any active filters in parent contexts to the array
+    foreach ($filteractives as $row) {
+        $depth = array_search($row->contextid, $parentcontextids);
+        if ($depth !== false) {
+            // Find entry
+            if (!array_key_exists($row->filter, $courseactive)) {
+                $courseactive[$row->filter] = 0;
+            }
+            // This maths copes with reading rows in any order. Turning on/off
+            // at site level counts 1, at next level down 4, at next level 9,
+            // then 16, etc. This means the deepest level always wins, except
+            // against the -9999 at top level.
+            $courseactive[$row->filter] +=
+                ($depth + 1) * ($depth + 1) * $row->active;
+
+            if ($row->active == TEXTFILTER_DISABLED) {
+                $banned[$row->filter] = true;
+            }
+        } else {
+            // Build list of other rows indexed by contextid
+            if (!array_key_exists($row->contextid, $remainingactives)) {
+                $remainingactives[$row->contextid] = array();
+            }
+            $remainingactives[$row->contextid][] = $row;
+        }
+    }
+
+    // Chuck away the ones that aren't active
+    foreach ($courseactive as $filter=>$score) {
+        if ($score <= 0) {
+            unset($courseactive[$filter]);
+        } else {
+            $courseactive[$filter] = array();
+        }
+    }
+
+    // Loop through the contexts to reconstruct filter_active lists for each
+    // cm on the course
+    if (!isset($FILTERLIB_PRIVATE->active)) {
+        $FILTERLIB_PRIVATE->active = array();
+    }
+    foreach ($cmcontextids as $contextid) {
+        // Copy course list
+        $FILTERLIB_PRIVATE->active[$contextid] = $courseactive;
+
+        // Are there any changes to the active list?
+        if (array_key_exists($contextid, $remainingactives)) {
+            foreach ($remainingactives[$contextid] as $row) {
+                if ($row->active > 0 && empty($banned[$row->filter])) {
+                    // If it's marked active for specific context, add entry
+                    // (doesn't matter if one exists already)
+                    $FILTERLIB_PRIVATE->active[$contextid][$row->filter] = array();
+                } else {
+                    // If it's marked inactive, remove entry (doesn't matter
+                    // if it doesn't exist)
+                    unset($FILTERLIB_PRIVATE->active[$contextid][$row->filter]);
+                }
+            }
+        }
+    }
+
+    // Process all config rows to add config data to these entries
+    foreach ($filterconfigs as $row) {
+        if (isset($FILTERLIB_PRIVATE->active[$row->contextid][$row->filter])) {
+            $FILTERLIB_PRIVATE->active[$row->contextid][$row->filter][$row->name] = $row->value;
+        }
+    }
+}
+
 /**
  * List all of the filters that are available in this context, and what the
  * local and inherited states of that filter are.
diff --git a/lib/simpletest/testfilterconfig.php b/lib/simpletest/testfilterconfig.php
index ccd3592700e..9f1ad0aef26 100644
--- a/lib/simpletest/testfilterconfig.php
+++ b/lib/simpletest/testfilterconfig.php
@@ -548,6 +548,180 @@ class filter_get_active_available_in_context_test extends UnitTestCaseUsingDatab
     }
 }
 
+class filter_preload_activities_test extends UnitTestCaseUsingDatabase {
+    private $syscontext, $catcontext, $coursecontext, $activity1context, $activity2context;
+
+    public function setUp() {
+        parent::setUp();
+
+        // Make sure accesslib has cached a sensible system context object
+        // before we switch to the test DB.
+        $this->syscontext = get_context_instance(CONTEXT_SYSTEM);
+
+        // Create the table we need and switch to test DB.
+        $this->create_test_tables(array('filter_active', 'filter_config', 'context',
+            'course', 'course_modules', 'modules', 'course_sections',
+            'course_modules_availability', 'grade_items'), 'lib');
+        $this->create_test_tables(array('label'), 'mod/label');
+        $this->switch_to_test_db();
+
+        // Set up systcontext in the test database.
+        $this->syscontext->id = $this->testdb->insert_record('context', $this->syscontext);
+
+        // Make the course
+        $course = (object)array(
+            'shortname' => 'TEST101');
+        $course->id = $this->testdb->insert_record('course', $course);
+
+        // Set up category and course contexts
+        $this->catcontext = (object)array(
+            'contextlevel' => CONTEXT_COURSECAT,
+            'instanceid' => 1,
+            'depth' => 2,
+            'path' => '/1/2');
+        $this->catcontext->id = $this->testdb->insert_record('context', $this->catcontext);
+        $this->coursecontext = (object)array(
+            'contextlevel' => CONTEXT_COURSE,
+            'instanceid' => $course->id,
+            'depth' => 3,
+            'path' => '/1/2/3');
+        $this->coursecontext->id = $this->testdb->insert_record('context', $this->coursecontext);
+
+        // Set up section
+        $section = (object)array(
+            'course' => $course->id);
+        $section->id = $this->testdb->insert_record('course_sections', $section);
+
+        // Make course-modules
+        $mod = (object)array(
+            'name' => 'label',
+            'visible' => 1);
+        $mod->id = $this->testdb->insert_record('modules', $mod);
+        $label1 = (object)array(
+            'course' => $course->id,
+            'intro' => 'Intro 1',
+            'name' => 'Label 1');
+        $label1->id = $this->testdb->insert_record('label', $label1);
+        $cm1 = (object)array(
+            'course' => $course->id,
+            'section' => $section->id,
+            'module' => $mod->id,
+            'instance' => $label1->id);
+        $cm1->id = $this->testdb->insert_record('course_modules', $cm1);
+        $label2 = (object)array(
+            'course' => $course->id,
+            'intro' => 'Intro 2',
+            'name' => 'Label 2');
+        $label2->id = $this->testdb->insert_record('label', $label2);
+        $cm2 = (object)array(
+            'course' => $course->id,
+            'section' => $section->id,
+            'module' => $mod->id,
+            'instance' => $label2->id);
+        $cm2->id = $this->testdb->insert_record('course_modules', $cm2);
+        $this->testdb->set_field('course_sections', 'sequence',
+            "$cm1->id,$cm2->id", array('id' => $section->id));
+
+        // Set up activity contexts
+        $this->activity1context = (object)array(
+            'contextlevel' => CONTEXT_MODULE,
+            'instanceid' => $cm1->id,
+            'depth' => 4,
+            'path' => '/1/2/3/4');
+        $this->activity1context->id =
+                $this->testdb->insert_record('context', $this->activity1context);
+        $this->activity2context = (object)array(
+                'contextlevel' => CONTEXT_MODULE,
+                'instanceid' => $cm2->id,
+                'depth' => 4,
+                'path' => '/1/2/3/5');
+        $this->activity2context->id =
+                $this->testdb->insert_record('context', $this->activity2context);
+    }
+
+    private function assert_matches($modinfo) {
+        global $FILTERLIB_PRIVATE;
+
+        // Use preload cache...
+        $FILTERLIB_PRIVATE = new stdClass;
+        filter_preload_activities($modinfo);
+
+        // Get data and check no queries are made
+        $before = $this->testdb->perf_get_reads();
+        $plfilters1 = filter_get_active_in_context($this->activity1context);
+        $plfilters2 = filter_get_active_in_context($this->activity2context);
+        $after = $this->testdb->perf_get_reads();
+        $this->assertEqual($before, $after);
+
+        // Repeat without cache and check it makes queries now
+        $FILTERLIB_PRIVATE = new stdClass;
+        $before = $this->testdb->perf_get_reads();
+        $filters1 = filter_get_active_in_context($this->activity1context);
+        $filters2 = filter_get_active_in_context($this->activity2context);
+        $after = $this->testdb->perf_get_reads();
+        $this->assertTrue($after > $before);
+
+        // Check they match
+        $this->assertEqual($plfilters1, $filters1);
+        $this->assertEqual($plfilters2, $filters2);
+    }
+
+    public function test_preload() {
+        global $FILTERLIB_PRIVATE;
+
+        // Get course and modinfo
+        $course = $this->testdb->get_record('course', array('id'=>1));
+        $modinfo = new course_modinfo($course, 1);
+
+        // Note: All the tests in this function check that the result from the
+        // preloaded cache is the same as the result from calling the standard
+        // function without preloading.
+
+        // Initially, check with no filters enabled
+        $this->assert_matches($modinfo);
+
+        // Enable filter globally, check
+        filter_set_global_state('filter/name', TEXTFILTER_ON);
+        $this->assert_matches($modinfo);
+
+        // Disable for activity 2
+        filter_set_local_state('filter/name', $this->activity2context->id, TEXTFILTER_OFF);
+        $this->assert_matches($modinfo);
+
+        // Disable at category
+        filter_set_local_state('filter/name', $this->catcontext->id, TEXTFILTER_OFF);
+        $this->assert_matches($modinfo);
+
+        // Enable for activity 1
+        filter_set_local_state('filter/name', $this->activity1context->id, TEXTFILTER_ON);
+        $this->assert_matches($modinfo);
+
+        // Disable globally
+        filter_set_global_state('filter/name', TEXTFILTER_DISABLED);
+        $this->assert_matches($modinfo);
+
+        // Add another 2 filters
+        filter_set_global_state('filter/frog', TEXTFILTER_ON);
+        filter_set_global_state('filter/zombie', TEXTFILTER_ON);
+        $this->assert_matches($modinfo);
+
+        // Disable random one of these in each context
+        filter_set_local_state('filter/zombie', $this->activity1context->id, TEXTFILTER_OFF);
+        filter_set_local_state('filter/frog', $this->activity2context->id, TEXTFILTER_OFF);
+        $this->assert_matches($modinfo);
+
+        // Now do some filter options
+        filter_set_local_config('filter/name', $this->activity1context->id, 'a', 'x');
+        filter_set_local_config('filter/zombie', $this->activity1context->id, 'a', 'y');
+        filter_set_local_config('filter/frog', $this->activity1context->id, 'a', 'z');
+        // These last two don't do anything as they are not at final level but I
+        // thought it would be good to have that verified in test
+        filter_set_local_config('filter/frog', $this->coursecontext->id, 'q', 'x');
+        filter_set_local_config('filter/frog', $this->catcontext->id, 'q', 'z');
+        $this->assert_matches($modinfo);
+    }
+}
+
 class filter_delete_config_test extends UnitTestCaseUsingDatabase {
     protected $syscontext;
 
@@ -659,4 +833,3 @@ class filter_filter_set_applies_to_strings extends UnitTestCaseUsingDatabase {
         $this->assertTrue($CFG->filterall);
     }
 }
-