Re: [PATCH] i386 !NUMA node_to_cpumask broken in early boot

[Zwane Mwaikambo]

On Fri, 19 Aug 2005, Andi Kleen wrote:

> On Thu, Aug 18, 2005 at 08:07:53PM -0600, Zwane Mwaikambo wrote:
> > node_to_cpumask on non NUMA systems is broken if used before all the 
> > processors have been brought up as it returns cpu_online_map, as opposed 
> > to NUMA i386 systems which does it earlier than AP bringup. So return 
> > which processors responded via cpu_present_map and switch to 
> > cpu_online_map during normal runtime. This was found whilst testing a 
> > patch which does node dependent work before APs have all gone online.
> 
> Very ugly and will probably cause code bloat.
> 
> If anything define a special early_node_to ... function for this.

Thanks for the feedback, ugly indeed, i was really trying to avoid adding 
a new API function or extra cpu_* variables. Ok, here is an 
early_node_to_cpumask instead.

Signed-off-by: Zwane Mwaikambo <zwane@xxxxxxxxxxxxxxxx>

Index: linux-2.6.13-rc5-mm1/include/asm-i386/topology.h
===================================================================
RCS file: /home/cvsroot/linux-2.6.13-rc5-mm1/include/asm-i386/topology.h,v
retrieving revision 1.1.1.1
diff -u -p -B -r1.1.1.1 topology.h
--- linux-2.6.13-rc5-mm1/include/asm-i386/topology.h	7 Aug 2005 21:38:36 -0000	1.1.1.1
+++ linux-2.6.13-rc5-mm1/include/asm-i386/topology.h	19 Aug 2005 02:47:10 -0000
@@ -92,6 +92,7 @@ extern unsigned long node_end_pfn[];
 extern unsigned long node_remap_size[];
 
 #define node_has_online_mem(nid) (node_start_pfn[nid] != node_end_pfn[nid])
+#define early_node_to_cpumask(nid)	node_to_cpumask(nid)
 
 #else /* !CONFIG_NUMA */
 /*
@@ -99,6 +100,14 @@ extern unsigned long node_remap_size[];
  * above macros here.
  */
 
+static inline cpumask_t early_node_to_cpumask(int nid)
+{
+	if (unlikely(system_state == SYSTEM_BOOTING))
+		return cpu_present_map;
+
+	return cpu_online_map;
+}
+
 #include <asm-generic/topology.h>
 
 #endif /* CONFIG_NUMA */
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/