[XFS] Rework the dquot hash sizing heuristics.

SGI-PV: 943123
SGI-Modid: xfs-linux:xfs-kern:24012a

Signed-off-by: Nathan Scott <nathans@sgi.com>

3 files changed, 20 insertions, 31 deletions

diff --git a/fs/xfs/linux-2.6/xfs_linux.h b/fs/xfs/linux-2.6/xfs_linux.h
index 52b240539531..44fed10af0dd 100644
--- a/fs/xfs/linux-2.6/xfs_linux.h
+++ b/fs/xfs/linux-2.6/xfs_linux.h
@@ -217,19 +217,7 @@ static inline void set_buffer_unwritten_io(struct buffer_head *bh)
 #define Q_XSETPQLIM     XQM_CMD(10)     /* set projects disk limits */
 #define Q_XGETPQUOTA    XQM_CMD(11)     /* get projects disk limits */
 
-/* IRIX uses a dynamic sizing algorithm (ndquot = 200 + numprocs*2) */
-/* we may well need to fine-tune this if it ever becomes an issue.  */
-#define DQUOT_MAX_HEURISTIC     1024    /* NR_DQUOTS */
-#define ndquot                  DQUOT_MAX_HEURISTIC
-
-/* IRIX uses the current size of the name cache to guess a good value */
-/* - this isn't the same but is a good enough starting point for now. */
-#define DQUOT_HASH_HEURISTIC    files_stat.nr_files
-
-/* IRIX inodes maintain the project ID also, zero this field on Linux */
-#define DEFAULT_PROJID  0
-#define dfltprid        DEFAULT_PROJID
-
+#define dfltprid        0
 #define MAXPATHLEN      1024
 
 #define MIN(a,b)        (min(a,b))
diff --git a/fs/xfs/quota/xfs_qm.c b/fs/xfs/quota/xfs_qm.c
index 79aadb1c1f44..1aea42d71a64 100644
--- a/fs/xfs/quota/xfs_qm.c
+++ b/fs/xfs/quota/xfs_qm.c
@@ -60,8 +60,9 @@
  * quota functionality, including maintaining the freelist and hash
  * tables of dquots.
  */
-mutex_t xfs_Gqm_lock;
+mutex_t         xfs_Gqm_lock;
 struct xfs_qm   *xfs_Gqm;
+uint            ndquot;
 
 kmem_zone_t     *qm_dqzone;
 kmem_zone_t     *qm_dqtrxzone;
@@ -108,25 +109,25 @@ extern mutex_t	qcheck_lock;
 STATIC struct xfs_qm *
 xfs_Gqm_init(void)
 {
-        xfs_qm_t                *xqm;
-        int                     hsize, i;
-
-        xqm = kmem_zalloc(sizeof(xfs_qm_t), KM_SLEEP);
-        ASSERT(xqm);
+        xfs_dqhash_t    *udqhash, *gdqhash;
+        xfs_qm_t        *xqm;
+        uint            i, hsize, flags = KM_SLEEP | KM_MAYFAIL;
 
         /*
          * Initialize the dquot hash tables.
          */
-        hsize = (DQUOT_HASH_HEURISTIC < XFS_QM_NCSIZE_THRESHOLD) ?
-                XFS_QM_HASHSIZE_LOW : XFS_QM_HASHSIZE_HIGH;
-        xqm->qm_dqhashmask = hsize - 1;
+        hsize = XFS_QM_HASHSIZE_HIGH;
+        while (!(udqhash = kmem_zalloc(hsize * sizeof(xfs_dqhash_t), flags))) {
+                if ((hsize >>= 1) <= XFS_QM_HASHSIZE_LOW)
+                        flags = KM_SLEEP;
+        }
+        gdqhash = kmem_zalloc(hsize * sizeof(xfs_dqhash_t), KM_SLEEP);
+        ndquot = hsize << 8;
 
-        xqm->qm_usr_dqhtable = (xfs_dqhash_t *)kmem_zalloc(hsize *
-                                                      sizeof(xfs_dqhash_t),
-                                                      KM_SLEEP);
-        xqm->qm_grp_dqhtable = (xfs_dqhash_t *)kmem_zalloc(hsize *
-                                                      sizeof(xfs_dqhash_t),
-                                                      KM_SLEEP);
+        xqm = kmem_zalloc(sizeof(xfs_qm_t), KM_SLEEP);
+        xqm->qm_dqhashmask = hsize - 1;
+        xqm->qm_usr_dqhtable = udqhash;
+        xqm->qm_grp_dqhtable = gdqhash;
         ASSERT(xqm->qm_usr_dqhtable != NULL);
         ASSERT(xqm->qm_grp_dqhtable != NULL);
 
diff --git a/fs/xfs/quota/xfs_qm.h b/fs/xfs/quota/xfs_qm.h
index 43219c97b371..12da259f2fcb 100644
--- a/fs/xfs/quota/xfs_qm.h
+++ b/fs/xfs/quota/xfs_qm.h
@@ -26,6 +26,7 @@
 struct xfs_qm;
 struct xfs_inode;
 
+extern uint             ndquot;
 extern mutex_t          xfs_Gqm_lock;
 extern struct xfs_qm    *xfs_Gqm;
 extern kmem_zone_t      *qm_dqzone;
@@ -51,9 +52,8 @@ extern kmem_zone_t	*qm_dqtrxzone;
 /*
  * Dquot hashtable constants/threshold values.
  */
-#define XFS_QM_NCSIZE_THRESHOLD         5000
-#define XFS_QM_HASHSIZE_LOW             32
-#define XFS_QM_HASHSIZE_HIGH            64
+#define XFS_QM_HASHSIZE_LOW             (NBPP / sizeof(xfs_dqhash_t))
+#define XFS_QM_HASHSIZE_HIGH            ((NBPP * 4) / sizeof(xfs_dqhash_t))
 
 /*
  * We output a cmn_err when quotachecking a quota file with more than