[203/272] memsw: handle swapaccount kernel parameter correctly

Greg KH
2011-02-16T00:24:01Z

From: Michal Hocko <mhocko@suse.cz>

commit fceda1bf498677501befc7da72fd2e4de7f18466 upstream.

__setup based kernel command line parameters handlers which are handled in
obsolete_checksetup are provided with the parameter value including =
(more precisely everything right after the parameter name).

This means that the current implementation of swapaccount[=1|0] doesn't
work at all because if there is a value for the parameter then we are
testing for "0" resp. "1" but we are getting "=0" resp. "=1" and if
there is no parameter value we are getting an empty string rather than
NULL.

The original noswapccount parameter, which doesn't care about the value,
works correctly.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
mm/memcontrol.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4930,9 +4930,9 @@ struct cgroup_subsys mem_cgroup_subsys =
static int __init enable_swap_account(char *s)
{
/* consider enabled if no parameter or 1 is given */
- if (!s || !strcmp(s, "1"))
+ if (!(*s) || !strcmp(s, "=1"))
really_do_swap_account = 1;
- else if (!strcmp(s, "0"))
+ else if (!strcmp(s, "=0"))
really_do_swap_account = 0;
return 1;
}
@@ -4940,7 +4940,7 @@ __setup("swapaccount", enable_swap_accou

static int __init disable_swap_account(char *s)
{
- enable_swap_account("0");
+ enable_swap_account("=0");
return 1;
}
__setup("noswapaccount", disable_swap_account);