Re: [PATCH] mm: unhide vmstat_text definition for CONFIG_SMP

[Christoph Lameter]

On Wed, 11 May 2016, Arnd Bergmann wrote:

> In randconfig builds with sysfs, procfs and numa all disabled,
> but SMP enabled, we now get a link error in the newly introduced
> vmstat_refresh function:
>
> mm/built-in.o: In function `vmstat_refresh':

Hmmm... vmstat_refresh should not be build if CONFIG_PROC_FS is not set
since there will be no way to trigger it. Lets not complicate this
further.



Subject: Do not build vmstat_refresh if there is no procfs support

It makes no sense to build functionality into the kernel that
cannot be used and causes build issues.

Signed-off-by: Christoph Lameter <cl@xxxxxxxxx>

Index: linux/mm/vmstat.c
===================================================================
--- linux.orig/mm/vmstat.c
+++ linux/mm/vmstat.c
@@ -1358,7 +1358,6 @@ static const struct file_operations proc
 	.llseek		= seq_lseek,
 	.release	= seq_release,
 };
-#endif /* CONFIG_PROC_FS */

 #ifdef CONFIG_SMP
 static struct workqueue_struct *vmstat_wq;
@@ -1422,7 +1421,10 @@ int vmstat_refresh(struct ctl_table *tab
 		*lenp = 0;
 	return 0;
 }
+#endif /* CONFIG_SMP */
+#endif /* CONFIG_PROC_FS */

+#ifdef CONFIG_SMP
 static void vmstat_update(struct work_struct *w)
 {
 	if (refresh_cpu_vm_stats(true)) {