lustre/kernel_patches/patches/quota-avoid-dqget-calls-sles11sp2.patch

   1 --- linux-3.0/fs/quota/dquot.c.orig     2013-07-18 09:46:28.000000000 -0400
   2 +++ linux-3.0/fs/quota/dquot.c  2013-07-18 09:49:20.000000000 -0400
   3 @@ -1342,7 +1342,7 @@
   4  static void __dquot_initialize(struct inode *inode, int type)
   5  {
   6         unsigned int id = 0;
   7 -       int cnt;
   8 +       int cnt, ret = 0, dq_get = 0;
   9         struct dquot *got[MAXQUOTAS];
  10         struct super_block *sb = inode->i_sb;
  11         qsize_t rsv;
  12 @@ -1352,7 +1352,14 @@
  13         if (!dquot_active(inode))
  14                 return;
  15
  16 -       /* First get references to structures we might need. */
  17 +       /* In most case, the i_dquot should have been initialized, except
  18 +        * the newly allocated one. We'd always try to skip the dqget() and
  19 +        * dqput() calls to avoid unnecessary global lock contention. */
  20 +       if (!(inode->i_state & I_NEW))
  21 +               goto init_idquot;
  22 +
  23 +get_dquots:
  24 +       dq_get = 1;
  25         for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
  26                 got[cnt] = NULL;
  27                 if (type != -1 && cnt != type)
  28 @@ -1367,7 +1374,7 @@
  29                 }
  30                 got[cnt] = dqget(sb, id, cnt);
  31         }
  32 -
  33 +init_idquot:
  34         spin_lock(&inode->i_lock);
  35         if (IS_NOQUOTA(inode))
  36                 goto out_err;
  37 @@ -1381,6 +1388,10 @@
  38                 if (!got[cnt])
  39                         continue;
  40                 if (!inode->i_dquot[cnt]) {
  41 +                       if (dq_get == 0) {
  42 +                               spin_unlock(&inode->i_lock);
  43 +                               goto get_dquots;
  44 +                       }
  45                         inode->i_dquot[cnt] = got[cnt];
  46                         got[cnt] = NULL;
  47                         /*
  48 @@ -1388,7 +1399,7 @@
  49                          * did a write before quota was turned on
  50                          */
  51                         rsv = inode_get_rsv_space(inode);
  52 -                       if (unlikely(rsv)) {
  53 +                       if (unlikely(rsv) && likely(inode->i_dquot[cnt])) {
  54                                 spin_lock(&dq_data_lock);
  55                                 dquot_resv_space(inode->i_dquot[cnt], rsv);
  56                                 spin_unlock(&dq_data_lock);