Commit e27e6151 authored Apr 14, 2011 by Ben Hutchings Committed by Linus Torvalds Apr 14, 2011

mm/thp: use conventional format for boolean attributes



The conventional format for boolean attributes in sysfs is numeric ("0" or
"1" followed by new-line).  Any boolean attribute can then be read and
written using a generic function.  Using the strings "yes [no]", "[yes]
no" (read), "yes" and "no" (write) will frustrate this.

[akpm@linux-foundation.org: use kstrtoul()]
[akpm@linux-foundation.org: test_bit() doesn't return 1/0, per Neil]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <jweiner@redhat.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Tested-by: David Rientjes <rientjes@google.com>
Cc: NeilBrown <neilb@suse.de>
Cc: <stable@kernel.org> 	[2.6.38.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b836aec5

mm/huge_memory.c

+14 −10

Original line number	Diff line number	Diff line
		@@ -244,24 +244,28 @@ static ssize_t single_flag_show(struct kobject *kobj,
		struct kobj_attribute attr, char buf,
		enum transparent_hugepage_flag flag)
		{
		if (test_bit(flag, &transparent_hugepage_flags))
		return sprintf(buf, "[yes] no\n");
		else
		return sprintf(buf, "yes [no]\n");
		return sprintf(buf, "%d\n",
		!!test_bit(flag, &transparent_hugepage_flags));
		}

		static ssize_t single_flag_store(struct kobject *kobj,
		struct kobj_attribute *attr,
		const char *buf, size_t count,
		enum transparent_hugepage_flag flag)
		{
		if (!memcmp("yes", buf,
		min(sizeof("yes")-1, count))) {
		unsigned long value;
		int ret;

		ret = kstrtoul(buf, 10, &value);
		if (ret < 0)
		return ret;
		if (value > 1)
		return -EINVAL;

		if (value)
		set_bit(flag, &transparent_hugepage_flags);
		} else if (!memcmp("no", buf,
		min(sizeof("no")-1, count))) {
		else
		clear_bit(flag, &transparent_hugepage_flags);
		} else
		return -EINVAL;

		return count;
		}