Commit 0b5e2588 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'sysctl' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-misc-2.6 

* 'sysctl' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-misc-2.6:
  SYSCTL: Add a mutex to the page_alloc zone order sysctl
  SYSCTL: Print binary sysctl warnings (nearly) only once
parents 6067d7e4 443c6f14

kernel/sysctl_binary.c

+30 −1
Original line number Diff line number Diff line
@@ -1417,6 +1417,35 @@ static void deprecated_sysctl_warning(const int *name, int nlen) 
	return;

}



#define WARN_ONCE_HASH_BITS 8

#define WARN_ONCE_HASH_SIZE (1<<WARN_ONCE_HASH_BITS)



static DECLARE_BITMAP(warn_once_bitmap, WARN_ONCE_HASH_SIZE);



#define FNV32_OFFSET 2166136261U

#define FNV32_PRIME 0x01000193



/*

 * Print each legacy sysctl (approximately) only once.

 * To avoid making the tables non-const use a external

 * hash-table instead.

 * Worst case hash collision: 6, but very rarely.

 * NOTE! We don't use the SMP-safe bit tests. We simply

 * don't care enough.

 */

static void warn_on_bintable(const int *name, int nlen)

{

	int i;

	u32 hash = FNV32_OFFSET;



	for (i = 0; i < nlen; i++)

		hash = (hash ^ name[i]) * FNV32_PRIME;

	hash %= WARN_ONCE_HASH_SIZE;

	if (__test_and_set_bit(hash, warn_once_bitmap))

		return;

	deprecated_sysctl_warning(name, nlen);

}



static ssize_t do_sysctl(int __user *args_name, int nlen,

	void __user *oldval, size_t oldlen, void __user *newval, size_t newlen)

{
@@ -1431,7 +1460,7 @@ static ssize_t do_sysctl(int __user *args_name, int nlen, 
		if (get_user(name[i], args_name + i))

			return -EFAULT;



	deprecated_sysctl_warning(name, nlen);

	warn_on_bintable(name, nlen);



	return binary_sysctl(name, nlen, oldval, oldlen, newval, newlen);

}

mm/page_alloc.c

+7 −4
Original line number Diff line number Diff line
@@ -2402,13 +2402,14 @@ int numa_zonelist_order_handler(ctl_table *table, int write, 
{

	char saved_string[NUMA_ZONELIST_ORDER_LEN];

	int ret;

	static DEFINE_MUTEX(zl_order_mutex);



	mutex_lock(&zl_order_mutex);

	if (write)

		strncpy(saved_string, (char*)table->data,

			NUMA_ZONELIST_ORDER_LEN);

		strcpy(saved_string, (char*)table->data);

	ret = proc_dostring(table, write, buffer, length, ppos);

	if (ret)

		return ret;

		goto out;

	if (write) {

		int oldval = user_zonelist_order;

		if (__parse_numa_zonelist_order((char*)table->data)) {
@@ -2421,7 +2422,9 @@ int numa_zonelist_order_handler(ctl_table *table, int write, 
		} else if (oldval != user_zonelist_order)

			build_all_zonelists();

	}

	return 0;

out:

	mutex_unlock(&zl_order_mutex);

	return ret;

}