From harisri@internode.on.net Mon Jan 31 23:10:25 2005
From: Srihari Vijayaraghavan <harisri@internode.on.net>
To: Jens Axboe <axboe@suse.de>
Subject: Re: [PATCH] elevator: print default selection
Date: Mon, 31 Jan 2005 23:10:25 +1100
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At a cost of one extra variable, this one works great for all cases:

Hopefully the extra steps in elevator_init() won't hinder the performance, as 
elevator_init() seems to be the safest place to determine the default 
elevator, as all elevators are registered, when it is called.

Sorry if it is no good.

Thank you.
Hari.

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--- 2.6.11/drivers/block/elevator.c	2005-01-22 15:22:55.000000000 +1100
+++ test/drivers/block/elevator.c	2005-01-31 22:38:36.000000000 +1100
@@ -180,6 +180,8 @@
 
 __setup("elevator=", elevator_setup);
 
+static int default_msg = 0;
+
 int elevator_init(request_queue_t *q, char *name)
 {
 	struct elevator_type *e = NULL;
@@ -195,6 +197,12 @@
 	if (!e)
 		return -EINVAL;
 
+	if (!default_msg && !strcmp(e->elevator_name, chosen_elevator)) {
+		printk(KERN_INFO "using %s as default io scheduler\n",
+						chosen_elevator);
+		default_msg = 1;
+	}
+
 	eq = kmalloc(sizeof(struct elevator_queue), GFP_KERNEL);
 	if (!eq) {
 		elevator_put(e->elevator_type);
@@ -513,10 +521,7 @@
 	list_add_tail(&e->list, &elv_list);
 	spin_unlock_irq(&elv_list_lock);
 
-	printk(KERN_INFO "io scheduler %s registered", e->elevator_name);
-	if (!strcmp(e->elevator_name, chosen_elevator))
-		printk(" (default)");
-	printk("\n");
+	printk(KERN_INFO "io scheduler %s registered\n", e->elevator_name);
 	return 0;
 }
 EXPORT_SYMBOL_GPL(elv_register);

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