On Tue 12-05-20 14:41:46, Huang Ying wrote: > To improve the code readability and get random number with higher > quality. I understand the readability argument but why should prandom_u32_max (which I was not aware of) provide a higher quality randomness? > Signed-off-by: "Huang, Ying" <ying.huang@xxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxx> > Cc: Minchan Kim <minchan@xxxxxxxxxx> > Cc: Tim Chen <tim.c.chen@xxxxxxxxxxxxxxx> > Cc: Hugh Dickins <hughd@xxxxxxxxxx> To the change itself Acked-by: Michal Hocko <mhocko@xxxxxxxx> > --- > mm/swapfile.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/swapfile.c b/mm/swapfile.c > index a0a123e59ce6..2ec8b21201d6 100644 > --- a/mm/swapfile.c > +++ b/mm/swapfile.c > @@ -3220,7 +3220,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) > * select a random position to start with to help wear leveling > * SSD > */ > - p->cluster_next = 1 + (prandom_u32() % p->highest_bit); > + p->cluster_next = 1 + prandom_u32_max(p->highest_bit); > nr_cluster = DIV_ROUND_UP(maxpages, SWAPFILE_CLUSTER); > > cluster_info = kvcalloc(nr_cluster, sizeof(*cluster_info), > -- > 2.26.2 -- Michal Hocko SUSE Labs
