From 7638cbfb6bfe1662173441b1b2f9b13995a96c87 Mon Sep 17 00:00:00 2001
From: Timo Kokkonen <kaapeli@itanic.dy.fi>
Date: Sun, 16 Oct 2011 21:19:08 +0300
Subject: [PATCH] analyze.c: Factor out counting stats for a single pageframe

This makes it possible to re-use the pageframe stats counting in cases
it is not desirable to count the stats for every pages in the tree.

Signed-off-by: Timo Kokkonen <kaapeli@itanic.dy.fi>
---
 analyze.c | 136 ++++++++++++++++++++++++++++--------------------------
 1 file changed, 70 insertions(+), 66 deletions(-)

diff --git a/analyze.c b/analyze.c
index a032eff..547a3ad 100644
--- a/analyze.c
+++ b/analyze.c
@@ -84,89 +84,93 @@ struct analyze_frames {
 #define bintree_ops_to_af(bintree_ops)				\
 	container_of((bintree_ops), struct analyze_frames, ops)
 
-static int count_pages(struct rb_root *root, struct analyze_frames *af)
+static void count_page(struct pageframe *pf, struct analyze_frames *af)
 {
-	struct pageframe *pf;
 	struct maps_list *ml;
-	int i, pages = 0;
-
-	pf = rb_to_pageframe(rb_first(root));
+	int i;
 
-	while (pf) {
-		pages++;
+	if (af->pid) {
+		/* Find pages which reference at least once a pid */
+		list_for_each_entry(ml, &pf->ml, list) {
+			if (ml->map->pid == af->pid)
+				goto get_stats;
+		}
+		return;
+	} else if (af->pidlist && af->map) {
+		/*
+		 * Find pages that reference at least once all of the
+		 * given pids and a given mapping
+		 */
+		struct pidlist *pid;
+		int matches = 0;
 
-		if (af->pid) {
-			/* Find pages which reference at least once a pid */
-			list_for_each_entry(ml, &pf->ml, list) {
-				if (ml->map->pid == af->pid)
-					goto get_stats;
+		/*
+		 * Check that we reference the given mapping at least
+		 * once
+		 */
+		list_for_each_entry(ml, &pf->ml, list) {
+			if (ml->map == af->map) {
+				matches++;
+				break;
 			}
-			goto next;
-		} else if (af->pidlist && af->map) {
-			/*
-			 * Find pages that reference at least once all
-			 * of the given pids and a given mapping
-			 */
-			struct pidlist *pid;
-			int matches = 0;
+		}
 
-			/*
-			 * Check that we reference the given mapping
-			 * at least once
-			 */
+		if (!matches)
+			return;
+		matches = 0;
+
+		/*
+		 * Check that we reference all of the given pids
+		 * too. The order of the loops is important here. We
+		 * must scan through all the references and test for a
+		 * given pid. If we would iterate through the
+		 * references in the outer loop, we might get
+		 * duplicate matches for a pid since it is possible
+		 * that a page is mapped multiple times in a process's
+		 * addrses space.
+		 */
+		list_for_each_entry(pid, af->pidlist, list) {
 			list_for_each_entry(ml, &pf->ml, list) {
-				if (ml->map == af->map) {
+				if (ml->map->pid == pid->pid) {
 					matches++;
 					break;
 				}
 			}
 
-			if (!matches)
-				goto next;
-			matches = 0;
-
 			/*
-			 * Check that we reference all of the given
-			 * pids too. The order of the loops is
-			 * important here. We must scan through all
-			 * the references and test for a given pid. If
-			 * we would iterate through the references in
-			 * the outer loop, we might get duplicate
-			 * matches for a pid since it is possible that
-			 * a page is mapped multiple times in a
-			 * process's addrses space.
+			 * If we have found as many matches as ther
+			 * are pids, we will count the stats
 			 */
-			list_for_each_entry(pid, af->pidlist, list) {
-				list_for_each_entry(ml, &pf->ml, list) {
-					if (ml->map->pid == pid->pid) {
-						matches++;
-						break;
-					}
-				}
-
-				/*
-				 * If we have found as many matches as ther
-				 * are pids, we will count the stats
-				 */
-				if (matches == af->pids)
-					goto get_stats;
-			}
-			goto next;
+			if (matches == af->pids)
+				goto get_stats;
 		}
+		return;
+	}
 
 get_stats:
-		if (page_present(pf))
-			af->pages_present++;
-		else if (page_swapped(pf))
-			af->pages_swapped++;
-		if (pf->kpagecount == 1)
-			af->pages_unique++;
-
-		for (i = 0; i < KPAGEFLAGS_NUM; i++)
-			if (kpageflag_is_set(pf, i))
-				af->kpageflag[i]++;
-
-next:
+	if (page_present(pf))
+		af->pages_present++;
+	else if (page_swapped(pf))
+		af->pages_swapped++;
+	if (pf->kpagecount == 1)
+		af->pages_unique++;
+
+	for (i = 0; i < KPAGEFLAGS_NUM; i++)
+		if (kpageflag_is_set(pf, i))
+			af->kpageflag[i]++;
+}
+
+static int count_pages(struct rb_root *root, struct analyze_frames *af)
+{
+	struct pageframe *pf;
+	int pages = 0;
+
+	pf = rb_to_pageframe(rb_first(root));
+
+	while (pf) {
+		pages++;
+		count_page(pf, af);
+
 		pf = rb_to_pageframe(rb_next(&pf->tree));
 	}
 
-- 
2.45.0