Print this page
11945 pool import performance regression due to repeated libshare initialization
Reviewed by: Sanjay Nadkarni <sanjay.nadkarni@nexenta.com>
Reviewed by: Evan Layton <evan.layton@nexenta.com>
Reviewed by: Dan McDonald <danmcd@joyent.com>
Reviewed by: Jason King <jason.brian.king@gmail.com>
@@ -610,10 +610,11 @@
* initialized in _zfs_init_libshare() are actually present.
*/
static sa_handle_t (*_sa_init)(int);
static sa_handle_t (*_sa_init_arg)(int, void *);
+static int (*_sa_service)(sa_handle_t);
static void (*_sa_fini)(sa_handle_t);
static sa_share_t (*_sa_find_share)(sa_handle_t, char *);
static int (*_sa_enable_share)(sa_share_t, char *);
static int (*_sa_disable_share)(sa_share_t, char *);
static char *(*_sa_errorstr)(int);
@@ -652,10 +653,12 @@
if ((libshare = dlopen(path, RTLD_LAZY | RTLD_GLOBAL)) != NULL) {
_sa_init = (sa_handle_t (*)(int))dlsym(libshare, "sa_init");
_sa_init_arg = (sa_handle_t (*)(int, void *))dlsym(libshare,
"sa_init_arg");
_sa_fini = (void (*)(sa_handle_t))dlsym(libshare, "sa_fini");
+ _sa_service = (int (*)(sa_handle_t))dlsym(libshare,
+ "sa_service");
_sa_find_share = (sa_share_t (*)(sa_handle_t, char *))
dlsym(libshare, "sa_find_share");
_sa_enable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
"sa_enable_share");
_sa_disable_share = (int (*)(sa_share_t, char *))dlsym(libshare,
@@ -675,14 +678,15 @@
if (_sa_init == NULL || _sa_init_arg == NULL ||
_sa_fini == NULL || _sa_find_share == NULL ||
_sa_enable_share == NULL || _sa_disable_share == NULL ||
_sa_errorstr == NULL || _sa_parse_legacy_options == NULL ||
_sa_needs_refresh == NULL || _sa_get_zfs_handle == NULL ||
- _sa_zfs_process_share == NULL ||
+ _sa_zfs_process_share == NULL || _sa_service == NULL ||
_sa_update_sharetab_ts == NULL) {
_sa_init = NULL;
_sa_init_arg = NULL;
+ _sa_service = NULL;
_sa_fini = NULL;
_sa_disable_share = NULL;
_sa_enable_share = NULL;
_sa_errorstr = NULL;
_sa_parse_legacy_options = NULL;
@@ -837,26 +841,39 @@
char sourcestr[ZFS_MAXPROPLEN];
libzfs_handle_t *hdl = zhp->zfs_hdl;
sa_share_t share;
zfs_share_proto_t *curr_proto;
zprop_source_t sourcetype;
+ int service = SA_INIT_ONE_SHARE_FROM_HANDLE;
int ret;
if (!zfs_is_mountable(zhp, mountpoint, sizeof (mountpoint), NULL))
return (0);
+ /*
+ * Function may be called in a loop from higher up stack, with libshare
+ * initialized for multiple shares (SA_INIT_SHARE_API_SELECTIVE).
+ * zfs_init_libshare_arg will refresh the handle's cache if necessary.
+ * In this case we do not want to switch to per share initialization.
+ * Specify SA_INIT_SHARE_API to do full refresh, if refresh required.
+ */
+ if ((hdl->libzfs_sharehdl != NULL) && (_sa_service != NULL) &&
+ (_sa_service(hdl->libzfs_sharehdl) ==
+ SA_INIT_SHARE_API_SELECTIVE)) {
+ service = SA_INIT_SHARE_API;
+ }
+
for (curr_proto = proto; *curr_proto != PROTO_END; curr_proto++) {
/*
* Return success if there are no share options.
*/
if (zfs_prop_get(zhp, proto_table[*curr_proto].p_prop,
shareopts, sizeof (shareopts), &sourcetype, sourcestr,
ZFS_MAXPROPLEN, B_FALSE) != 0 ||
strcmp(shareopts, "off") == 0)
continue;
- ret = zfs_init_libshare_arg(hdl, SA_INIT_ONE_SHARE_FROM_HANDLE,
- zhp);
+ ret = zfs_init_libshare_arg(hdl, service, zhp);
if (ret != SA_OK) {
(void) zfs_error_fmt(hdl, EZFS_SHARENFSFAILED,
dgettext(TEXT_DOMAIN, "cannot share '%s': %s"),
zfs_get_name(zhp), _sa_errorstr != NULL ?
_sa_errorstr(ret) : "");
@@ -946,26 +963,34 @@
zfs_share_proto_t proto)
{
sa_share_t share;
int err;
char *mntpt;
+ int service = SA_INIT_ONE_SHARE_FROM_NAME;
/*
* Mountpoint could get trashed if libshare calls getmntany
* which it does during API initialization, so strdup the
* value.
*/
mntpt = zfs_strdup(hdl, mountpoint);
/*
- * make sure libshare initialized, initialize everything because we
- * don't know what other unsharing may happen later. Functions up the
- * stack are allowed to initialize instead a subset of shares at the
- * time the set is known.
+ * Function may be called in a loop from higher up stack, with libshare
+ * initialized for multiple shares (SA_INIT_SHARE_API_SELECTIVE).
+ * zfs_init_libshare_arg will refresh the handle's cache if necessary.
+ * In this case we do not want to switch to per share initialization.
+ * Specify SA_INIT_SHARE_API to do full refresh, if refresh required.
*/
- if ((err = zfs_init_libshare_arg(hdl, SA_INIT_ONE_SHARE_FROM_NAME,
- (void *)name)) != SA_OK) {
+ if ((hdl->libzfs_sharehdl != NULL) && (_sa_service != NULL) &&
+ (_sa_service(hdl->libzfs_sharehdl) ==
+ SA_INIT_SHARE_API_SELECTIVE)) {
+ service = SA_INIT_SHARE_API;
+ }
+
+ err = zfs_init_libshare_arg(hdl, service, (void *)name);
+ if (err != SA_OK) {
free(mntpt); /* don't need the copy anymore */
return (zfs_error_fmt(hdl, proto_table[proto].p_unshare_err,
dgettext(TEXT_DOMAIN, "cannot unshare '%s': %s"),
name, _sa_errorstr(err)));
}
@@ -1530,13 +1555,13 @@
zfs_mount_one, &ms, B_TRUE);
if (ms.ms_mntstatus != 0)
ret = ms.ms_mntstatus;
/*
- * Share all filesystems that need to be shared. This needs to be
- * a separate pass because libshare is not mt-safe, and so we need
- * to share serially.
+ * Initialize libshare SA_INIT_SHARE_API_SELECTIVE here
+ * to avoid unnecessary load/unload of the libshare API
+ * per shared dataset downstream.
*/
sharearg.zhandle_arr = cb.cb_handles;
sharearg.zhandle_len = cb.cb_used;
if ((ret = zfs_init_libshare_arg(zhp->zpool_hdl,
SA_INIT_SHARE_API_SELECTIVE, &sharearg)) != 0)