Re: [ANNOUNCE] 3.0-rc7-rt0

[Thomas Gleixner <tglx@linutronix.de>]

On Thu, 21 Jul 2011, hermann wrote:
> I try to build the 3.0-rc7-rt0 but fail with the following message:
>  CC [M]  fs/ext3/balloc.o
> In file included from include/linux/jbd.h:247:0,
>                  from fs/ext3/balloc.c:18:

Find below a patch on top of rt0 which fixes this build failure and
some other stuff.

Thanks,

	tglx

-----------

Index: linux-2.6/kernel/timer.c
===================================================================
--- linux-2.6.orig/kernel/timer.c
+++ linux-2.6/kernel/timer.c
@@ -654,6 +654,36 @@ static struct tvec_base *lock_timer_base
 	}
 }
 
+#ifndef CONFIG_PREEMPT_RT_FULL
+static inline struct tvec_base *switch_timer_base(struct timer_list *timer,
+						  struct tvec_base *old,
+						  struct tvec_base *new)
+{
+	/* See the comment in lock_timer_base() */
+	timer_set_base(timer, NULL);
+	spin_unlock(&old->lock);
+	spin_lock(&new->lock);
+	timer_set_base(timer, new);
+	return new;
+}
+#else
+static inline struct tvec_base *switch_timer_base(struct timer_list *timer,
+						  struct tvec_base *old,
+						  struct tvec_base *new)
+{
+	/*
+	 * We cannot do the above because we might be preempted and
+	 * then the preempter would see NULL and loop forever.
+	 */
+	if (spin_trylock(&new->lock)) {
+		timer_set_base(timer, new);
+		spin_unlock(&old->lock);
+		return new;
+	}
+	return old;
+}
+#endif
+
 static inline int
 __mod_timer(struct timer_list *timer, unsigned long expires,
 						bool pending_only, int pinned)
@@ -699,14 +729,8 @@ __mod_timer(struct timer_list *timer, un
 		 * handler yet has not finished. This also guarantees that
 		 * the timer is serialized wrt itself.
 		 */
-		if (likely(base->running_timer != timer)) {
-			/* See the comment in lock_timer_base() */
-			timer_set_base(timer, NULL);
-			spin_unlock(&base->lock);
-			base = new_base;
-			spin_lock(&base->lock);
-			timer_set_base(timer, base);
-		}
+		if (likely(base->running_timer != timer))
+			base = switch_timer_base(timer, base, new_base);
 	}
 
 	timer->expires = expires;
Index: linux-2.6/mm/page_alloc.c
===================================================================
--- linux-2.6.orig/mm/page_alloc.c
+++ linux-2.6/mm/page_alloc.c
@@ -1943,8 +1943,8 @@ __alloc_pages_direct_compact(gfp_t gfp_m
 	if (*did_some_progress != COMPACT_SKIPPED) {
 
 		/* Page migration frees to the PCP lists but we want merging */
-		drain_pages(get_cpu());
-		put_cpu();
+		drain_pages(get_cpu_light());
+		put_cpu_light();
 
 		page = get_page_from_freelist(gfp_mask, nodemask,
 				order, zonelist, high_zoneidx,
Index: linux-2.6/include/linux/buffer_head.h
===================================================================
--- linux-2.6.orig/include/linux/buffer_head.h
+++ linux-2.6/include/linux/buffer_head.h
@@ -74,7 +74,9 @@ struct buffer_head {
 	atomic_t b_count;		/* users using this buffer_head */
 #ifdef CONFIG_PREEMPT_RT_BASE
 	spinlock_t b_uptodate_lock;
-#if defined(CONFIG_JBD) || defined(CONFIG_JBD2)
+#if defined(CONFIG_JBD) || defined(CONFIG_JBD_MODULE) || \
+    defined(CONFIG_JBD2) || defined(CONFIG_JBD2_MODULE)
+	spinlock_t b_state_lock;
 	spinlock_t b_state_lock;
 	spinlock_t b_journal_head_lock;
 #endif