* [PATCH] ext2/3: use prandom_u32() instead of get_random_bytes() [not found] <530D4BBB.6090600@huawei.com> @ 2014-02-26 2:32 ` ZhangZhen 2014-02-26 11:08 ` Jan Kara 0 siblings, 1 reply; 2+ messages in thread From: ZhangZhen @ 2014-02-26 2:32 UTC (permalink / raw) To: jack; +Cc: linux-ext4 Many of the uses of get_random_bytes() do not actually need cryptographically secure random numbers. Replace those uses with a call to prandom_u32(), which is faster and which doesn't consume entropy from the /dev/random driver. The commit dd1f723bf56bd96efc9d90e9e60dc511c79de48f has made that for ext4, and i did the same for ext2/3. Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com> --- fs/ext2/ialloc.c | 2 +- fs/ext3/ialloc.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c index 7cadd82..32f131a 100644 --- a/fs/ext2/ialloc.c +++ b/fs/ext2/ialloc.c @@ -284,7 +284,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent) int best_ndir = inodes_per_group; int best_group = -1; - get_random_bytes(&group, sizeof(group)); + grp = prandom_u32(); parent_group = (unsigned)group % ngroups; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; diff --git a/fs/ext3/ialloc.c b/fs/ext3/ialloc.c index 082afd7..60e63e3 100644 --- a/fs/ext3/ialloc.c +++ b/fs/ext3/ialloc.c @@ -215,7 +215,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent) int best_ndir = inodes_per_group; int best_group = -1; - get_random_bytes(&group, sizeof(group)); + grp = prandom_u32(); parent_group = (unsigned)group % ngroups; for (i = 0; i < ngroups; i++) { group = (parent_group + i) % ngroups; -- 1.8.1.4 . ^ permalink raw reply related [flat|nested] 2+ messages in thread
* Re: [PATCH] ext2/3: use prandom_u32() instead of get_random_bytes() 2014-02-26 2:32 ` [PATCH] ext2/3: use prandom_u32() instead of get_random_bytes() ZhangZhen @ 2014-02-26 11:08 ` Jan Kara 0 siblings, 0 replies; 2+ messages in thread From: Jan Kara @ 2014-02-26 11:08 UTC (permalink / raw) To: ZhangZhen; +Cc: jack, linux-ext4 On Wed 26-02-14 10:32:41, ZhangZhen wrote: > Many of the uses of get_random_bytes() do not actually need > cryptographically secure random numbers. Replace those uses with a > call to prandom_u32(), which is faster and which doesn't consume > entropy from the /dev/random driver. > > The commit dd1f723bf56bd96efc9d90e9e60dc511c79de48f has made that for > ext4, and i did the same for ext2/3. Thanks. I've merged the patch to my tree. Honza > > Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com> > --- > fs/ext2/ialloc.c | 2 +- > fs/ext3/ialloc.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/fs/ext2/ialloc.c b/fs/ext2/ialloc.c > index 7cadd82..32f131a 100644 > --- a/fs/ext2/ialloc.c > +++ b/fs/ext2/ialloc.c > @@ -284,7 +284,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent) > int best_ndir = inodes_per_group; > int best_group = -1; > > - get_random_bytes(&group, sizeof(group)); > + grp = prandom_u32(); > parent_group = (unsigned)group % ngroups; > for (i = 0; i < ngroups; i++) { > group = (parent_group + i) % ngroups; > diff --git a/fs/ext3/ialloc.c b/fs/ext3/ialloc.c > index 082afd7..60e63e3 100644 > --- a/fs/ext3/ialloc.c > +++ b/fs/ext3/ialloc.c > @@ -215,7 +215,7 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent) > int best_ndir = inodes_per_group; > int best_group = -1; > > - get_random_bytes(&group, sizeof(group)); > + grp = prandom_u32(); > parent_group = (unsigned)group % ngroups; > for (i = 0; i < ngroups; i++) { > group = (parent_group + i) % ngroups; > -- > 1.8.1.4 > > > . > > > > -- Jan Kara <jack@suse.cz> SUSE Labs, CR ^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2014-02-26 11:08 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <530D4BBB.6090600@huawei.com>
2014-02-26 2:32 ` [PATCH] ext2/3: use prandom_u32() instead of get_random_bytes() ZhangZhen
2014-02-26 11:08 ` Jan Kara
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.