[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] [PATCH] xen: selfballoon: remove unnecessary static in frontswap_selfshrink()

Remove unnecessary static on local variables last_frontswap_pages and
tgt_frontswap_pages. Such variables are initialized before being used,
on every execution path throughout the function. The statics have no
benefit and, removing them reduce the code size.

This issue was detected using Coccinelle and the following semantic patch:

@bad exists@
position p;
identifier x;
type T;

static T x@p;
x = <+...x...+>

identifier x;
expression e;
type T;
position p != bad.p;

 T x@p;
 ... when != x
     when strict
?x = e;

You can see a significant difference in the code size after executing
the size command, before and after the code change:

   text    data     bss     dec     hex filename
   5633    3452     384    9469    24fd drivers/xen/xen-selfballoon.o

   text    data     bss     dec     hex filename
   5576    3308     256    9140    23b4 drivers/xen/xen-selfballoon.o

Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
 drivers/xen/xen-selfballoon.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/xen/xen-selfballoon.c b/drivers/xen/xen-selfballoon.c
index 6662071..a67e955 100644
--- a/drivers/xen/xen-selfballoon.c
+++ b/drivers/xen/xen-selfballoon.c
@@ -151,8 +151,8 @@ static unsigned long frontswap_inertia_counter;
 static void frontswap_selfshrink(void)
        static unsigned long cur_frontswap_pages;
-       static unsigned long last_frontswap_pages;
-       static unsigned long tgt_frontswap_pages;
+       unsigned long last_frontswap_pages;
+       unsigned long tgt_frontswap_pages;
        last_frontswap_pages = cur_frontswap_pages;
        cur_frontswap_pages = frontswap_curr_pages();

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.