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>

5 files changed, 63 insertions, 1 deletions

diff --git a/xlators/mount/fuse/src/fuse-bridge.c b/xlators/mount/fuse/src/fuse-bridge.c
index 360e1443cf2..3a620ac7e7f 100644
--- a/xlators/mount/fuse/src/fuse-bridge.c
+++ b/xlators/mount/fuse/src/fuse-bridge.c
@@ -4604,6 +4604,15 @@ init (xlator_t *this_xl)
 	GF_OPTION_INIT("fopen-keep-cache", priv->fopen_keep_cache, bool,
 		cleanup_exit);
 
+	GF_OPTION_INIT("gid-timeout", priv->gid_cache_timeout, int32,
+		cleanup_exit);
+
+	if (gid_cache_init(&priv->gid_cache, priv->gid_cache_timeout) < 0) {
+		gf_log("glusterfs-fuse", GF_LOG_ERROR, "Failed to initialize "
+			"group cache.");
+		goto cleanup_exit;
+	}
+
         cmd_args = &this_xl->ctx->cmd_args;
         fsname = cmd_args->volfile;
         if (!fsname && cmd_args->volfile_server) {
@@ -4768,5 +4777,9 @@ struct volume_options options[] = {
 	  .type = GF_OPTION_TYPE_BOOL,
 	  .default_value = "false"
 	},
+	{ .key = {"gid-timeout"},
+	  .type = GF_OPTION_TYPE_INT,
+	  .default_value = "0"
+	},
         { .key = {NULL} },
 };
diff --git a/xlators/mount/fuse/src/fuse-bridge.h b/xlators/mount/fuse/src/fuse-bridge.h
index dcd9629246c..bc35eb0617d 100644
--- a/xlators/mount/fuse/src/fuse-bridge.h
+++ b/xlators/mount/fuse/src/fuse-bridge.h
@@ -55,6 +55,7 @@
 #include "list.h"
 #include "dict.h"
 #include "syncop.h"
+#include "gidcache.h"
 
 #if defined(GF_LINUX_HOST_OS) || defined(__NetBSD__)
 #define FUSE_OP_HIGH (FUSE_POLL + 1)
@@ -110,7 +111,9 @@ struct fuse_private {
         gf_boolean_t         selinux;
         gf_boolean_t         read_only;
 	gf_boolean_t	     fopen_keep_cache;
+	int32_t		     gid_cache_timeout;
         fdtable_t           *fdtable;
+	gid_cache_t	     gid_cache;
 
         /* For fuse-reverse-validation */
         int                  revchan_in;
diff --git a/xlators/mount/fuse/src/fuse-helpers.c b/xlators/mount/fuse/src/fuse-helpers.c
index bcad97fc742..729c8fb2cd4 100644
--- a/xlators/mount/fuse/src/fuse-helpers.c
+++ b/xlators/mount/fuse/src/fuse-helpers.c
@@ -245,6 +245,46 @@ out:
 #endif /* GF_LINUX_HOST_OS */
 }
 
+/*
+ * Get the groups for the PID associated with this frame. If enabled,
+ * use the gid cache to reduce group list collection.
+ */
+static void get_groups(fuse_private_t *priv, call_frame_t *frame)
+{
+	int i;
+	const gid_list_t *gl;
+	gid_list_t agl;
+
+	if (!priv->gid_cache_timeout) {
+		frame_fill_groups(frame);
+		return;
+	}
+
+	gl = gid_cache_lookup(&priv->gid_cache, frame->root->pid);
+	if (gl) {
+		frame->root->ngrps = gl->gl_count;
+		for (i = 0; i < gl->gl_count; i++)
+			frame->root->groups[i] = gl->gl_list[i];
+		gid_cache_release(&priv->gid_cache, gl);
+		return;
+	}
+
+	frame_fill_groups (frame);
+
+	agl.gl_id = frame->root->pid;
+	agl.gl_count = frame->root->ngrps;
+	agl.gl_list = GF_CALLOC(frame->root->ngrps, sizeof(gid_t),
+			gf_fuse_mt_gids_t);
+	if (!agl.gl_list)
+		return;
+
+	for (i = 0; i < frame->root->ngrps; i++)
+		agl.gl_list[i] = frame->root->groups[i];
+
+	if (gid_cache_add(&priv->gid_cache, &agl) != 1)
+		GF_FREE(agl.gl_list);
+}
+
 call_frame_t *
 get_call_frame_for_req (fuse_state_t *state)
 {
@@ -272,7 +312,7 @@ get_call_frame_for_req (fuse_state_t *state)
                                           state->lk_owner);
         }
 
-        frame_fill_groups (frame);
+	get_groups(priv, frame);
 
         if (priv && priv->client_pid_set)
                 frame->root->pid = priv->client_pid;
diff --git a/xlators/mount/fuse/src/fuse-mem-types.h b/xlators/mount/fuse/src/fuse-mem-types.h
index 9c6a1c67a7a..d1c5e511b0e 100644
--- a/xlators/mount/fuse/src/fuse-mem-types.h
+++ b/xlators/mount/fuse/src/fuse-mem-types.h
@@ -31,6 +31,7 @@ enum gf_fuse_mem_types_ {
         gf_fuse_mt_fuse_state_t,
         gf_fuse_mt_fd_ctx_t,
         gf_fuse_mt_graph_switch_args_t,
+	gf_fuse_mt_gids_t,
         gf_fuse_mt_end
 };
 #endif
diff --git a/xlators/mount/fuse/utils/mount.glusterfs.in b/xlators/mount/fuse/utils/mount.glusterfs.in
index b623d3428b7..e585ba3b7fd 100755
--- a/xlators/mount/fuse/utils/mount.glusterfs.in
+++ b/xlators/mount/fuse/utils/mount.glusterfs.in
@@ -132,6 +132,10 @@ start_glusterfs ()
         cmd_line=$(echo "$cmd_line --entry-timeout=$entry_timeout");
     fi
 
+    if [ -n "$gid_timeout" ]; then
+	cmd_line=$(echo "$cmd_line --gid-timeout=$gid_timeout");
+    fi
+
     if [ -n "$fopen_keep_cache" ]; then
 	cmd_line=$(echo "$cmd_line --fopen-keep-cache");
     fi
@@ -325,6 +329,7 @@ main ()
                             "attribute-timeout")
                                 attribute_timeout=$value ;;
                             "entry-timeout")    entry_timeout=$value ;;
+			    "gid-timeout")	gid_timeout=$value ;;
                             *) echo "unknown option $key (ignored)" ;;
                         esac
                 esac