Re: percpu_counter_mod not getting into SMP kernel image whenext2/3 compiled as modules

From: Andrew Morton
Date: Mon Nov 10 2003 - 19:37:24 EST


Jeff Bowden <jlb@xxxxxxxxxxxxxxxxxxxxxx> wrote:
>
> In 2.6.9-test9 (also tried with bk15) I have ext2 and ext3 both
> configured as modules. When I do "modprobe ext3" it says:
>
> FATAL: Error inserting ext3
> (/lib/modules/2.6.0-test9-bug-t1/kernel/fs/ext3/ext3.ko): Unknown symbol
> in module, or unknown parameter (see dmesg)
>
> and dmesg says:
>
> ext3: Unknown symbol percpu_counter_mod

You'll be needing this:

diff -puN -L lib/percpu_counter.c lib/percpu_counter.c~percpu-counter-linkage-fix /dev/null
--- 25/lib/percpu_counter.c
+++ /dev/null 2002-08-30 16:31:37.000000000 -0700
@@ -1,21 +0,0 @@
-#include <linux/module.h>
-#include <linux/percpu_counter.h>
-#include <linux/sched.h>
-
-void percpu_counter_mod(struct percpu_counter *fbc, long amount)
-{
- int cpu = get_cpu();
- long count = fbc->counters[cpu].count;
-
- count += amount;
- if (count >= FBC_BATCH || count <= -FBC_BATCH) {
- spin_lock(&fbc->lock);
- fbc->count += count;
- spin_unlock(&fbc->lock);
- count = 0;
- }
- fbc->counters[cpu].count = count;
- put_cpu();
-}
-
-EXPORT_SYMBOL(percpu_counter_mod);
diff -puN lib/Makefile~percpu-counter-linkage-fix lib/Makefile
--- 25/lib/Makefile~percpu-counter-linkage-fix 2003-11-07 20:36:48.000000000 -0800
+++ 25-akpm/lib/Makefile 2003-11-07 20:36:48.000000000 -0800
@@ -9,7 +9,6 @@ lib-y := errno.o ctype.o string.o vsprin

lib-$(CONFIG_RWSEM_GENERIC_SPINLOCK) += rwsem-spinlock.o
lib-$(CONFIG_RWSEM_XCHGADD_ALGORITHM) += rwsem.o
-lib-$(CONFIG_SMP) += percpu_counter.o

ifneq ($(CONFIG_HAVE_DEC_LOCK),y)
lib-y += dec_and_lock.o
diff -puN mm/swap.c~percpu-counter-linkage-fix mm/swap.c
--- 25/mm/swap.c~percpu-counter-linkage-fix 2003-11-07 20:36:48.000000000 -0800
+++ 25-akpm/mm/swap.c 2003-11-07 20:36:48.000000000 -0800
@@ -14,6 +14,7 @@
*/

#include <linux/mm.h>
+#include <linux/sched.h>
#include <linux/kernel_stat.h>
#include <linux/swap.h>
#include <linux/mman.h>
@@ -23,6 +24,8 @@
#include <linux/module.h>
#include <linux/mm_inline.h>
#include <linux/buffer_head.h> /* for try_to_release_page() */
+#include <linux/module.h>
+#include <linux/percpu_counter.h>
#include <linux/percpu.h>

/* How many pages do we try to swap or page in/out together? */
@@ -380,6 +383,24 @@ void vm_acct_memory(long pages)
EXPORT_SYMBOL(vm_acct_memory);
#endif

+#ifdef CONFIG_SMP
+void percpu_counter_mod(struct percpu_counter *fbc, long amount)
+{
+ int cpu = get_cpu();
+ long count = fbc->counters[cpu].count;
+
+ count += amount;
+ if (count >= FBC_BATCH || count <= -FBC_BATCH) {
+ spin_lock(&fbc->lock);
+ fbc->count += count;
+ spin_unlock(&fbc->lock);
+ count = 0;
+ }
+ fbc->counters[cpu].count = count;
+ put_cpu();
+}
+EXPORT_SYMBOL(percpu_counter_mod);
+#endif

/*
* Perform any setup for the swap system

_

-
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/