Re: [PATCH 1/4] fastboot: Asynchronous function calls to speed up kernel boot

[Arjan van de Ven <arjan@infradead.org>]

On Sun, 4 Jan 2009 10:33:34 -0800 (PST)
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> IOW, I'd just suggest changing the interface so that
> "async_schedule()" also returns the cookie. 
> 

>From 6b436c0fab92c50cae7ba3bcd9bcfebf2c9596f7 Mon Sep 17 00:00:00 2001
From: Arjan van de Ven <arjan@linux.intel.com>
Date: Sun, 4 Jan 2009 10:47:27 -0800
Subject: [PATCH] fastboot: return the cookie from async_schedule()

Put this code back as suggested by Linus; even if there's no users right
now it makes conceptual sense and the cost is basically zero.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
---
 include/linux/async.h |    2 +-
 kernel/async.c        |   10 ++++++----
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/include/linux/async.h b/include/linux/async.h
index b54d83a..678d4fd 100644
--- a/include/linux/async.h
+++ b/include/linux/async.h
@@ -15,7 +15,7 @@
 typedef u64 async_cookie_t;
 typedef void (async_func_ptr) (void *data, async_cookie_t cookie);
 
-extern void async_schedule(async_func_ptr *ptr, void *data);
+extern async_cookie_t async_schedule(async_func_ptr *ptr, void *data);
 extern void async_synchronize_full(void);
 extern void async_synchronize_cookie(async_cookie_t cookie);
 
diff --git a/kernel/async.c b/kernel/async.c
index 9918fe5..8ecebf5 100644
--- a/kernel/async.c
+++ b/kernel/async.c
@@ -156,32 +156,34 @@ out:
 }
 
 
-void async_schedule(async_func_ptr *ptr, void *data)
+async_cookie_t async_schedule(async_func_ptr *ptr, void *data)
 {
 	struct async_entry *entry;
 	unsigned long flags;
+	async_cookie_t newcookie;
+	
 
 	/* allow irq-off callers */
 	entry = kzalloc(sizeof(struct async_entry), GFP_ATOMIC);
 	if (!entry) {
-		async_cookie_t newcookie;
 		spin_lock_irqsave(&async_lock, flags);
 		newcookie = next_cookie++;
 		spin_unlock_irqrestore(&async_lock, flags);
 
 		/* low on memory.. run synchronously */
 		ptr(data, newcookie);
-		return;
+		return newcookie;
 	}
 	entry->func = ptr;
 	entry->data = data;
 
 	spin_lock_irqsave(&async_lock, flags);
-	entry->cookie = next_cookie++;
+	newcookie = entry->cookie = next_cookie++;
 	list_add_tail(&entry->list, &async_pending);
 	atomic_inc(&entry_count);
 	spin_unlock_irqrestore(&async_lock, flags);
 	wake_up(&async_new);
+	return newcookie;
 }
 EXPORT_SYMBOL_GPL(async_schedule);
 
-- 
1.6.0.6


-- 
Arjan van de Ven 	Intel Open Source Technology Centre
For development, discussion and tips for power savings, 
visit http://www.lesswatts.org