Re: [PATCH 1/2] async: Handle kthread_run() return codes.

[Cornelia Huck <cornelia.huck@de.ibm.com>]

On Tue, 13 Jan 2009 16:51:15 +0000,
Ben Dooks <ben-linux@fluff.org> wrote:

> > @@ -315,11 +315,14 @@ static int async_manager_thread(void *un
> >  		ec = atomic_read(&entry_count);
> >  
> >  		while (tc < ec && tc < MAX_THREADS) {
> 
> why not add the following to stop the wrapping of kthread_run:
> 
> +   	    		struct task_struct *kt;
> 			kt = kthread_run(async_thread, NULL, "async/%i", tc);

Hm, I don't think avoiding wrapping is worth adding another variable.

> 			if (IS_ERR(kt))
> 				goto schedule;
> 
> also, I belive the goto isn't necessary, just break out of the while
> 
> 			if (IS_ERR(kt))
> 				break;

OK, that's a bit nicer. Updated patch follows.


If we fail to create the manager thread, fall back to non-fastboot.
If we fail to create an async thread, try again when the manager
thread runs again.

Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>

---
 kernel/async.c |    9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

--- linux-2.6.orig/kernel/async.c
+++ linux-2.6/kernel/async.c
@@ -315,7 +315,10 @@ static int async_manager_thread(void *un
 		ec = atomic_read(&entry_count);
 
 		while (tc < ec && tc < MAX_THREADS) {
-			kthread_run(async_thread, NULL, "async/%i", tc);
+			if (IS_ERR(kthread_run(async_thread, NULL, "async/%i",
+					       tc)))
+				/* Try again later. */
+				break;
 			atomic_inc(&thread_count);
 			tc++;
 		}
@@ -330,7 +333,9 @@ static int async_manager_thread(void *un
 static int __init async_init(void)
 {
 	if (async_enabled)
-		kthread_run(async_manager_thread, NULL, "async/mgr");
+		if (IS_ERR(kthread_run(async_manager_thread, NULL,
+				       "async/mgr")))
+			async_enabled = 0;
 	return 0;
 }