From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerard Lledo Date: Tue, 02 Jun 2009 11:32:16 +0000 Subject: Re: [PATCH] [JFFS2] Move jffs2_gcd_mtd threads to the new kthread Message-Id: <20090602113216.GA3513@tank> List-Id: References: <1243585181-2997-1-git-send-email-gerard.lledo@gmail.com> <20090601162010.ed69436f.akpm@linux-foundation.org> In-Reply-To: <20090601162010.ed69436f.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Andrew Morton Cc: dwmw2@infradead.org, kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mtd@lists.infradead.org On Mon, Jun 01, 2009 at 04:20:10PM -0700, Andrew Morton wrote: > On Fri, 29 May 2009 11:19:41 +0300 > Gerard Lledo wrote: > > > kernel_thread() is being depracated. This patch moves the jffs2 garbage > > collecting thread to the new kthread API with the minimal impact. > > > > Signed-off-by: Gerard Lledo > > --- > > fs/jffs2/background.c | 22 ++++++++++++++-------- > > 1 files changed, 14 insertions(+), 8 deletions(-) > > > > diff --git a/fs/jffs2/background.c b/fs/jffs2/background.c > > index e958010..077fa65 100644 > > --- a/fs/jffs2/background.c > > +++ b/fs/jffs2/background.c > > @@ -15,6 +15,7 @@ > > #include > > #include > > #include > > +#include > > #include "nodelist.h" > > > > > > @@ -31,7 +32,7 @@ void jffs2_garbage_collect_trigger(struct jffs2_sb_info *c) > > /* This must only ever be called when no GC thread is currently running */ > > int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c) > > { > > - pid_t pid; > > + struct task_struct *tsk; > > int ret = 0; > > > > BUG_ON(c->gc_task); > > @@ -39,15 +40,16 @@ int jffs2_start_garbage_collect_thread(struct jffs2_sb_info *c) > > init_completion(&c->gc_thread_start); > > init_completion(&c->gc_thread_exit); > > > > - pid = kernel_thread(jffs2_garbage_collect_thread, c, CLONE_FS|CLONE_FILES); > > - if (pid < 0) { > > - printk(KERN_WARNING "fork failed for JFFS2 garbage collect thread: %d\n", -pid); > > + tsk = kthread_create(jffs2_garbage_collect_thread, c, "jffs2_gcd_mtd%d", c->mtd->index); > > + if (IS_ERR(tsk)) { > > + printk(KERN_WARNING "fork failed for JFFS2 garbage collect thread: %ld\n", -PTR_ERR(tsk)); > > complete(&c->gc_thread_exit); > > - ret = pid; > > + ret = PTR_ERR(tsk); > > } else { > > - /* Wait for it... */ > > - D1(printk(KERN_DEBUG "JFFS2: Garbage collect thread is pid %d\n", pid)); > > + D1(printk(KERN_DEBUG "JFFS2: Garbage collect thread is pid %d\n", tsk->pid)); > > + wake_up_process(tsk); > > wait_for_completion(&c->gc_thread_start); > > + ret = tsk->pid; > > } > > A simple kthread_run() would be preferable here. The code presently > sort-of open-codes it. > > > return ret; > > Also, manipulating kernel threads via their pids is atypical and > inefficient. In-kernel it is better to refer to threads via their > task_struct*. > > Fortunately all callers of this function ignore its return value so I > expect we can simply change it to be void-returning. But that's a > cleanup which would best be done in a spearate patch. > OK, I'll redo the previous patch with kthread_run() instead. I will also post a different patch to cleanup the return value and use void.