[PATCH 08/10] staging: lustre: Dynamic LNet Configuration (DLC)

From: James Simmons
Date: Mon Feb 15 2016 - 10:26:19 EST


From: Amir Shehata <amir.shehata@xxxxxxxxx>

This is the first patch of a set of patches that enables DLC.

This patch adds some cleanup in the config.c as well as some
preparatory changes in peer.c to enable dynamic network
configuration

Signed-off-by: Amir Shehata <amir.shehata@xxxxxxxxx>
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-2456
Change-Id: I8c8bbf3b55acf4d76f22a8be587b553a70d31889
Reviewed-on: http://review.whamcloud.com/9830
Reviewed-by: Liang Zhen <liang.zhen@xxxxxxxxx>
Reviewed-by: James Simmons <uja.ornl@xxxxxxxxx>
Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
---
.../staging/lustre/include/linux/lnet/lib-lnet.h | 2 +-
.../staging/lustre/include/linux/lnet/lib-types.h | 5 +-
drivers/staging/lustre/lnet/lnet/api-ni.c | 8 +-
drivers/staging/lustre/lnet/lnet/config.c | 29 ++++-
drivers/staging/lustre/lnet/lnet/peer.c | 134 ++++++++++++++------
5 files changed, 124 insertions(+), 54 deletions(-)

diff --git a/drivers/staging/lustre/include/linux/lnet/lib-lnet.h b/drivers/staging/lustre/include/linux/lnet/lib-lnet.h
index b2e5017..77d8e37 100644
--- a/drivers/staging/lustre/include/linux/lnet/lib-lnet.h
+++ b/drivers/staging/lustre/include/linux/lnet/lib-lnet.h
@@ -685,7 +685,7 @@ int lnet_parse_networks(struct list_head *nilist, char *networks);
int lnet_nid2peer_locked(lnet_peer_t **lpp, lnet_nid_t nid, int cpt);
lnet_peer_t *lnet_find_peer_locked(struct lnet_peer_table *ptable,
lnet_nid_t nid);
-void lnet_peer_tables_cleanup(void);
+void lnet_peer_tables_cleanup(lnet_ni_t *ni);
void lnet_peer_tables_destroy(void);
int lnet_peer_tables_create(void);
void lnet_debug_peer(lnet_nid_t nid);
diff --git a/drivers/staging/lustre/include/linux/lnet/lib-types.h b/drivers/staging/lustre/include/linux/lnet/lib-types.h
index d769c35..be650d4 100644
--- a/drivers/staging/lustre/include/linux/lnet/lib-types.h
+++ b/drivers/staging/lustre/include/linux/lnet/lib-types.h
@@ -351,6 +351,8 @@ typedef struct lnet_peer {
struct lnet_peer_table {
int pt_version; /* /proc validity stamp */
int pt_number; /* # peers extant */
+ /* # zombies to go to deathrow (and not there yet) */
+ int pt_zombies;
struct list_head pt_deathrow; /* zombie peers */
struct list_head *pt_hash; /* NID->peer hash */
};
@@ -616,9 +618,6 @@ typedef struct {
/* registered LNDs */
struct list_head ln_lnds;

- /* space for network names */
- char *ln_network_tokens;
- int ln_network_tokens_nob;
/* test protocol compatibility flags */
int ln_testprotocompat;

diff --git a/drivers/staging/lustre/lnet/lnet/api-ni.c b/drivers/staging/lustre/lnet/lnet/api-ni.c
index 58b30f1..cd68ca7 100644
--- a/drivers/staging/lustre/lnet/lnet/api-ni.c
+++ b/drivers/staging/lustre/lnet/lnet/api-ni.c
@@ -892,7 +892,7 @@ lnet_shutdown_lndnis(void)
* Clear the peer table and wait for all peers to go (they hold refs on
* their NIs)
*/
- lnet_peer_tables_cleanup();
+ lnet_peer_tables_cleanup(NULL);

lnet_net_lock(LNET_LOCK_EX);
/*
@@ -952,12 +952,6 @@ lnet_shutdown_lndnis(void)

the_lnet.ln_shutdown = 0;
lnet_net_unlock(LNET_LOCK_EX);
-
- if (the_lnet.ln_network_tokens) {
- LIBCFS_FREE(the_lnet.ln_network_tokens,
- the_lnet.ln_network_tokens_nob);
- the_lnet.ln_network_tokens = NULL;
- }
}

static int
diff --git a/drivers/staging/lustre/lnet/lnet/config.c b/drivers/staging/lustre/lnet/lnet/config.c
index e817eb3..bcc97b4 100644
--- a/drivers/staging/lustre/lnet/lnet/config.c
+++ b/drivers/staging/lustre/lnet/lnet/config.c
@@ -96,6 +96,8 @@ lnet_net_unique(__u32 net, struct list_head *nilist)
void
lnet_ni_free(struct lnet_ni *ni)
{
+ int i;
+
if (ni->ni_refs)
cfs_percpt_free(ni->ni_refs);

@@ -105,6 +107,10 @@ lnet_ni_free(struct lnet_ni *ni)
if (ni->ni_cpts)
cfs_expr_list_values_free(ni->ni_cpts, ni->ni_ncpts);

+ for (i = 0; i < LNET_MAX_INTERFACES && ni->ni_interfaces[i]; i++) {
+ LIBCFS_FREE(ni->ni_interfaces[i],
+ strlen(ni->ni_interfaces[i]) + 1);
+ }
LIBCFS_FREE(ni, sizeof(*ni));
}

@@ -199,8 +205,6 @@ lnet_parse_networks(struct list_head *nilist, char *networks)
return -ENOMEM;
}

- the_lnet.ln_network_tokens = tokens;
- the_lnet.ln_network_tokens_nob = tokensize;
memcpy(tokens, networks, tokensize);
tmp = tokens;
str = tokens;
@@ -321,7 +325,23 @@ lnet_parse_networks(struct list_head *nilist, char *networks)
goto failed;
}

- ni->ni_interfaces[niface++] = iface;
+ /*
+ * Allocate a separate piece of memory and copy
+ * into it the string, so we don't have
+ * a depencency on the tokens string. This way we
+ * can free the tokens at the end of the function.
+ * The newly allocated ni_interfaces[] can be
+ * freed when freeing the NI
+ */
+ LIBCFS_ALLOC(ni->ni_interfaces[niface],
+ strlen(iface) + 1);
+ if (!ni->ni_interfaces[niface]) {
+ CERROR("Can't allocate net interface name\n");
+ goto failed;
+ }
+ strncpy(ni->ni_interfaces[niface], iface,
+ strlen(iface));
+ niface++;
iface = comma;
} while (iface);

@@ -346,6 +366,8 @@ lnet_parse_networks(struct list_head *nilist, char *networks)
}

LASSERT(!list_empty(nilist));
+
+ LIBCFS_FREE(tokens, tokensize);
return 0;

failed_syntax:
@@ -362,7 +384,6 @@ lnet_parse_networks(struct list_head *nilist, char *networks)
cfs_expr_list_free(el);

LIBCFS_FREE(tokens, tokensize);
- the_lnet.ln_network_tokens = NULL;

return -EINVAL;
}
diff --git a/drivers/staging/lustre/lnet/lnet/peer.c b/drivers/staging/lustre/lnet/lnet/peer.c
index 00086ee..42b2d44 100644
--- a/drivers/staging/lustre/lnet/lnet/peer.c
+++ b/drivers/staging/lustre/lnet/lnet/peer.c
@@ -103,62 +103,116 @@ lnet_peer_tables_destroy(void)
the_lnet.ln_peer_tables = NULL;
}

+static void
+lnet_peer_table_cleanup_locked(lnet_ni_t *ni, struct lnet_peer_table *ptable)
+{
+ int i;
+ lnet_peer_t *lp;
+ lnet_peer_t *tmp;
+
+ for (i = 0; i < LNET_PEER_HASH_SIZE; i++) {
+ list_for_each_entry_safe(lp, tmp, &ptable->pt_hash[i],
+ lp_hashlist) {
+ if (ni && ni != lp->lp_ni)
+ continue;
+ list_del_init(&lp->lp_hashlist);
+ /* Lose hash table's ref */
+ ptable->pt_zombies++;
+ lnet_peer_decref_locked(lp);
+ }
+ }
+}
+
+static void
+lnet_peer_table_deathrow_wait_locked(struct lnet_peer_table *ptable,
+ int cpt_locked)
+{
+ int i;
+
+ for (i = 3; ptable->pt_zombies; i++) {
+ lnet_net_unlock(cpt_locked);
+
+ if (is_power_of_2(i)) {
+ CDEBUG(D_WARNING,
+ "Waiting for %d zombies on peer table\n",
+ ptable->pt_zombies);
+ }
+ set_current_state(TASK_UNINTERRUPTIBLE);
+ schedule_timeout(cfs_time_seconds(1) >> 1);
+ lnet_net_lock(cpt_locked);
+ }
+}
+
+static void
+lnet_peer_table_del_rtrs_locked(lnet_ni_t *ni, struct lnet_peer_table *ptable,
+ int cpt_locked)
+{
+ lnet_peer_t *lp;
+ lnet_peer_t *tmp;
+ lnet_nid_t lp_nid;
+ int i;
+
+ for (i = 0; i < LNET_PEER_HASH_SIZE; i++) {
+ list_for_each_entry_safe(lp, tmp, &ptable->pt_hash[i],
+ lp_hashlist) {
+ if (ni != lp->lp_ni)
+ continue;
+
+ if (!lp->lp_rtr_refcount)
+ continue;
+
+ lp_nid = lp->lp_nid;
+
+ lnet_net_unlock(cpt_locked);
+ lnet_del_route(LNET_NIDNET(LNET_NID_ANY), lp_nid);
+ lnet_net_lock(cpt_locked);
+ }
+ }
+}
+
void
-lnet_peer_tables_cleanup(void)
+lnet_peer_tables_cleanup(lnet_ni_t *ni)
{
struct lnet_peer_table *ptable;
+ struct list_head deathrow;
+ lnet_peer_t *lp;
int i;
- int j;

- LASSERT(the_lnet.ln_shutdown); /* i.e. no new peers */
+ INIT_LIST_HEAD(&deathrow);

+ LASSERT(the_lnet.ln_shutdown || ni);
+ /*
+ * If just deleting the peers for a NI, get rid of any routes these
+ * peers are gateways for.
+ */
cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
lnet_net_lock(i);
-
- for (j = 0; j < LNET_PEER_HASH_SIZE; j++) {
- struct list_head *peers = &ptable->pt_hash[j];
-
- while (!list_empty(peers)) {
- lnet_peer_t *lp = list_entry(peers->next,
- lnet_peer_t,
- lp_hashlist);
- list_del_init(&lp->lp_hashlist);
- /* lose hash table's ref */
- lnet_peer_decref_locked(lp);
- }
- }
-
+ lnet_peer_table_del_rtrs_locked(ni, ptable, i);
lnet_net_unlock(i);
}

+ /*
+ * Start the process of moving the applicable peers to
+ * deathrow.
+ */
cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
- LIST_HEAD(deathrow);
- lnet_peer_t *lp;
-
lnet_net_lock(i);
+ lnet_peer_table_cleanup_locked(ni, ptable);
+ lnet_net_unlock(i);
+ }

- for (j = 3; ptable->pt_number; j++) {
- lnet_net_unlock(i);
-
- if (!(j & (j - 1))) {
- CDEBUG(D_WARNING,
- "Waiting for %d peers on peer table\n",
- ptable->pt_number);
- }
- set_current_state(TASK_UNINTERRUPTIBLE);
- schedule_timeout(cfs_time_seconds(1) / 2);
- lnet_net_lock(i);
- }
+ /* Cleanup all entries on deathrow. */
+ cfs_percpt_for_each(ptable, i, the_lnet.ln_peer_tables) {
+ lnet_net_lock(i);
+ lnet_peer_table_deathrow_wait_locked(ptable, i);
list_splice_init(&ptable->pt_deathrow, &deathrow);
-
lnet_net_unlock(i);
+ }

- while (!list_empty(&deathrow)) {
- lp = list_entry(deathrow.next,
- lnet_peer_t, lp_hashlist);
- list_del(&lp->lp_hashlist);
- LIBCFS_FREE(lp, sizeof(*lp));
- }
+ while (!list_empty(&deathrow)) {
+ lp = list_entry(deathrow.next, lnet_peer_t, lp_hashlist);
+ list_del(&lp->lp_hashlist);
+ LIBCFS_FREE(lp, sizeof(*lp));
}
}

@@ -181,6 +235,8 @@ lnet_destroy_peer_locked(lnet_peer_t *lp)
lp->lp_ni = NULL;

list_add(&lp->lp_hashlist, &ptable->pt_deathrow);
+ LASSERT(ptable->pt_zombies > 0);
+ ptable->pt_zombies--;
}

lnet_peer_t *
--
1.7.1