LKML Archive on lore.kernel.org
 help / Atom feed
From: Davidlohr Bueso <dave@stgolabs.net>
To: akpm@linux-foundation.org
Cc: dave@stgolabs.net, linux-kernel@vger.kernel.org,
	Davidlohr Bueso <dbueso@suse.de>
Subject: [PATCH 3/4] lib/interval_tree_test: allow users to limit scope of endpoint
Date: Thu, 18 May 2017 10:49:35 -0700
Message-ID: <20170518174936.20265-4-dave@stgolabs.net> (raw)
In-Reply-To: <20170518174936.20265-1-dave@stgolabs.net>

Add a 'max_endpoint' parameter such that users may easily
limit the size of the intervals that are randomly generated.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
---
 lib/interval_tree_test.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/lib/interval_tree_test.c b/lib/interval_tree_test.c
index 1093f0496d5e..0fef6364a958 100644
--- a/lib/interval_tree_test.c
+++ b/lib/interval_tree_test.c
@@ -16,6 +16,7 @@ __param(int, perf_loops, 100000, "Number of iterations modifying the tree");
 __param(int, nsearches, 100, "Number of searches to the interval tree");
 __param(int, search_loops, 10000, "Number of iterations searching the tree");
 
+__param(uint, max_endpoint, ~0, "Largest value for the interval's endpoint");
 
 static struct rb_root root = RB_ROOT;
 static struct interval_tree_node *nodes = NULL;
@@ -40,18 +41,20 @@ static void init(void)
 	int i;
 
 	for (i = 0; i < nnodes; i++) {
-		u32 a = prandom_u32_state(&rnd);
-		u32 b = prandom_u32_state(&rnd);
-		if (a <= b) {
-			nodes[i].start = a;
-			nodes[i].last = b;
-		} else {
-			nodes[i].start = b;
-			nodes[i].last = a;
-		}
+		u32 b = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
+		u32 a = (prandom_u32_state(&rnd) >> 4) % b;
+
+		nodes[i].start = a;
+		nodes[i].last = b;
 	}
+
+	/*
+	 * Limit the search scope to what the user defined.
+	 * Otherwise we are merely measuring empty walks,
+	 * which is pointless.
+	 */
 	for (i = 0; i < nsearches; i++)
-		queries[i] = prandom_u32_state(&rnd);
+		queries[i] = (prandom_u32_state(&rnd) >> 4) % max_endpoint;
 }
 
 static int interval_tree_test_init(void)
-- 
2.12.0

  parent reply index

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-18 17:49 [PATCH -next 0/4] lib/interval_tree_test: some debugging improvements Davidlohr Bueso
2017-05-18 17:49 ` [PATCH 1/4] lib/interval_tree_test: allow the module to be compiled-in Davidlohr Bueso
2017-05-18 17:49 ` [PATCH 2/4] lib/interval_tree_test: make test options module parameters Davidlohr Bueso
2017-05-18 17:49 ` Davidlohr Bueso [this message]
2017-05-18 17:49 ` [PATCH 4/4] lib/interval_tree_test: allow full tree search Davidlohr Bueso

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170518174936.20265-4-dave@stgolabs.net \
    --to=dave@stgolabs.net \
    --cc=akpm@linux-foundation.org \
    --cc=dbueso@suse.de \
    --cc=linux-kernel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

LKML Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/lkml/0 lkml/git/0.git
	git clone --mirror https://lore.kernel.org/lkml/1 lkml/git/1.git
	git clone --mirror https://lore.kernel.org/lkml/2 lkml/git/2.git
	git clone --mirror https://lore.kernel.org/lkml/3 lkml/git/3.git
	git clone --mirror https://lore.kernel.org/lkml/4 lkml/git/4.git
	git clone --mirror https://lore.kernel.org/lkml/5 lkml/git/5.git
	git clone --mirror https://lore.kernel.org/lkml/6 lkml/git/6.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 lkml lkml/ https://lore.kernel.org/lkml \
		linux-kernel@vger.kernel.org linux-kernel@archiver.kernel.org
	public-inbox-index lkml


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-kernel


AGPL code for this site: git clone https://public-inbox.org/ public-inbox