libglusterfs,mount/fuse: implement gidcache mechanism in fuse-bridge

This change genericizes the cache mechanism implemented in commit
8efd2845 into libglusterfs/src/gidcache.[ch] and adds fuse-bridge as
a client. The cache mechanism is fundamentally equivalent, with some
minor changes:

  - Change cache key from uid_t to uint64_t.
  - Modify the cache add logic to locate and use an entry with a
    matching ID, should it already exist. This addresses a bug in
    the existing mechanism where an expired entry supercedes a newly
    added entry in lookup, causing repeated adds and flushing of a
    cache bucket.

The fuse group cache is disabled by default. It can be enabled via
the 'gid-timeout' fuse-bridge translator option and accompanying
mount option (i.e., '-o gid-timeout=1' for a 1s entry timeout).

BUG: 800892
Change-Id: I0b34a2263ca48dbb154790a4a44fc70b733e9114
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-on: http://review.gluster.com/3676
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>
Reviewed-by: Anand Avati <avati@redhat.com>

1 files changed, 3 insertions, 26 deletions

diff --git a/xlators/nfs/server/src/nfs.h b/xlators/nfs/server/src/nfs.h
index d2a0c1343..c3deba00a 100644
--- a/xlators/nfs/server/src/nfs.h
+++ b/xlators/nfs/server/src/nfs.h
@@ -29,6 +29,7 @@
 #include "dict.h"
 #include "xlator.h"
 #include "lkowner.h"
+#include "gidcache.h"
 
 #define GF_NFS                  "nfs"
 
@@ -65,28 +66,6 @@ struct nfs_initer_list {
         rpcsvc_program_t        *program;
 };
 
-/*
- * TBD: make the cache size tunable
- *
- * The current size represents a pretty trivial amount of memory, and should
- * provide good hit rates even for quite busy systems.  If we ever want to
- * support really large cache sizes, we'll need to do dynamic allocation
- * instead of just defining an array within nfs_state.  It doesn't make a
- * whole lot of sense to change the associativity, because it won't improve
- * hit rates all that much and will increase the maintenance cost as we have
- * to scan more entries with every lookup/update.
- */
-#define AUX_GID_CACHE_ASSOC     4
-#define AUX_GID_CACHE_BUCKETS   256
-#define AUX_GID_CACHE_SIZE      (AUX_GID_CACHE_ASSOC * AUX_GID_CACHE_BUCKETS)
-
-typedef struct {
-        uid_t                   uid;
-        int                     gid_count;
-        gid_t                   *gid_list;
-        time_t                  deadline;
-} aux_gid_list_t;
-
 struct nfs_state {
         rpcsvc_t                *rpcsvc;
         struct list_head        versions;
@@ -110,10 +89,8 @@ struct nfs_state {
         int                     mount_udp;
         struct rpc_clnt         *rpc_clnt;
         gf_boolean_t            server_aux_gids;
-        gf_lock_t               aux_gid_lock;
-        uint32_t                aux_gid_max_age;
-        unsigned int            aux_gid_nbuckets;
-        aux_gid_list_t          aux_gid_cache[AUX_GID_CACHE_SIZE];
+	uint32_t		server_aux_gids_max_age;
+	gid_cache_t		gid_cache;
 };
 
 #define gf_nfs_dvm_on(nfsstt)   (((struct nfs_state *)nfsstt)->dynamicvolumes == GF_NFS_DVM_ON)