Previously, IB GID cached used a lock per entry. This could result
in spending a lot of CPU cycles for locking and unlocking just
in order to find a GID. Changing this in favor of one lock per
a GID table.
Signed-off-by: Matan Barak <matanb@xxxxxxxxxxxx>
Reviewed-by: Haggai Eran <haggaie@xxxxxxxxxxxx>
---
drivers/infiniband/core/cache.c | 143 +++++++++++++++++++++++++---------------
1 file changed, 89 insertions(+), 54 deletions(-)
diff --git a/drivers/infiniband/core/cache.c b/drivers/infiniband/core/cache.c
index f0703d2..83aee7c 100644
--- a/drivers/infiniband/core/cache.c
+++ b/drivers/infiniband/core/cache.c
@@ -81,10 +81,6 @@ enum gid_table_write_action {
};
struct ib_gid_table_entry {
- /* This lock protects an entry from being
- * read and written simultaneously.
- */
- rwlock_t lock;
unsigned long props;
union ib_gid gid;
struct ib_gid_attr attr;
@@ -109,6 +105,10 @@ struct ib_gid_table {
* are locked by this lock.
**/
struct mutex lock;
+ /* This lock protects the table entries from being
+ * read and written simultaneously.
+ */
+ rwlock_t rwlock;
struct ib_gid_table_entry *data_vec;
};
@@ -125,6 +125,10 @@ static void dispatch_gid_change_event(struct ib_device *ib_dev, u8 port)
}
}
+/* This function expects that rwlock will be write locked in all
+ * scenarios and that lock will be locked in sleep-able (RoCE)
+ * scenarios.
+ */
static int write_gid(struct ib_device *ib_dev, u8 port,
struct ib_gid_table *table, int ix,
const union ib_gid *gid,
@@ -134,16 +138,14 @@ static int write_gid(struct ib_device *ib_dev, u8 port,
{
int ret = 0;
struct net_device *old_net_dev;
- unsigned long flags;
/* in rdma_cap_roce_gid_table, this funciton should be protected by a
* sleep-able lock.
*/
- write_lock_irqsave(&table->data_vec[ix].lock, flags);
if (rdma_cap_roce_gid_table(ib_dev, port)) {
table->data_vec[ix].props |= GID_TABLE_ENTRY_INVALID;
- write_unlock_irqrestore(&table->data_vec[ix].lock, flags);
+ write_unlock_irq(&table->rwlock);
/* GID_TABLE_WRITE_ACTION_MODIFY currently isn't supported by
* RoCE providers and thus only updates the cache.
*/
@@ -153,7 +155,7 @@ static int write_gid(struct ib_device *ib_dev, u8 port,
else if (action == GID_TABLE_WRITE_ACTION_DEL)
ret = ib_dev->del_gid(ib_dev, port, ix,
&table->data_vec[ix].context);
- write_lock_irqsave(&table->data_vec[ix].lock, flags);
+ write_lock_irq(&table->rwlock);
}
old_net_dev = table->data_vec[ix].attr.ndev;
@@ -175,11 +177,6 @@ static int write_gid(struct ib_device *ib_dev, u8 port,
table->data_vec[ix].props &= ~GID_TABLE_ENTRY_INVALID;
- write_unlock_irqrestore(&table->data_vec[ix].lock, flags);
-
- if (!ret)
- dispatch_gid_change_event(ib_dev, port);
-
return ret;
}
@@ -208,6 +205,7 @@ static int del_gid(struct ib_device *ib_dev, u8 port,
GID_TABLE_WRITE_ACTION_DEL, default_gid);
}
+/* rwlock should be read locked */
static int find_gid(struct ib_gid_table *table, const union ib_gid *gid,
const struct ib_gid_attr *val, bool default_gid,
unsigned long mask)
@@ -215,34 +213,29 @@ static int find_gid(struct ib_gid_table *table, const union ib_gid *gid,
int i;
for (i = 0; i < table->sz; i++) {
- unsigned long flags;
struct ib_gid_attr *attr = &table->data_vec[i].attr;
- read_lock_irqsave(&table->data_vec[i].lock, flags);
if (table->data_vec[i].props & GID_TABLE_ENTRY_INVALID)
- goto next;
+ continue;
if (mask & GID_ATTR_FIND_MASK_GID &&
memcmp(gid, &table->data_vec[i].gid, sizeof(*gid)))
- goto next;
+ continue;
if (mask & GID_ATTR_FIND_MASK_NETDEV &&
attr->ndev != val->ndev)
- goto next;
+ continue;
if (mask & GID_ATTR_FIND_MASK_DEFAULT &&
!!(table->data_vec[i].props & GID_TABLE_ENTRY_DEFAULT) !=
default_gid)
- goto next;
+ continue;
- read_unlock_irqrestore(&table->data_vec[i].lock, flags);
- return i;
-next:
- read_unlock_irqrestore(&table->data_vec[i].lock, flags);
+ break;
}
- return -1;
+ return i == table->sz ? -1 : i;
}
static void make_default_gid(struct net_device *dev, union ib_gid *gid)
@@ -282,6 +275,7 @@ int ib_cache_gid_add(struct ib_device *ib_dev, u8 port,
}
mutex_lock(&table->lock);
+ write_lock_irq(&table->rwlock);
ix = find_gid(table, gid, attr, false, GID_ATTR_FIND_MASK_GID |
GID_ATTR_FIND_MASK_NETDEV);
@@ -295,9 +289,12 @@ int ib_cache_gid_add(struct ib_device *ib_dev, u8 port,
goto out_unlock;
}
- add_gid(ib_dev, port, table, ix, gid, attr, false);
+ ret = add_gid(ib_dev, port, table, ix, gid, attr, false);
+ if (!ret)
+ dispatch_gid_change_event(ib_dev, port);
out_unlock:
+ write_unlock_irq(&table->rwlock);
mutex_unlock(&table->lock);
return ret;
}
@@ -312,6 +309,7 @@ int ib_cache_gid_del(struct ib_device *ib_dev, u8 port,
table = ports_table[port - rdma_start_port(ib_dev)];
mutex_lock(&table->lock);
+ write_lock_irq(&table->rwlock);
ix = find_gid(table, gid, attr, false,
GID_ATTR_FIND_MASK_GID |
@@ -320,9 +318,11 @@ int ib_cache_gid_del(struct ib_device *ib_dev, u8 port,
if (ix < 0)
goto out_unlock;
- del_gid(ib_dev, port, table, ix, false);
+ if (!del_gid(ib_dev, port, table, ix, false))
+ dispatch_gid_change_event(ib_dev, port);
out_unlock:
+ write_unlock_irq(&table->rwlock);
mutex_unlock(&table->lock);
return 0;
}
@@ -333,16 +333,24 @@ int ib_cache_gid_del_all_netdev_gids(struct ib_device *ib_dev, u8 port,
struct ib_gid_table **ports_table = ib_dev->cache.gid_cache;
struct ib_gid_table *table;
int ix;
+ bool deleted = false;
table = ports_table[port - rdma_start_port(ib_dev)];
mutex_lock(&table->lock);
+ write_lock_irq(&table->rwlock);
for (ix = 0; ix < table->sz; ix++)
if (table->data_vec[ix].attr.ndev == ndev)
- del_gid(ib_dev, port, table, ix, false);
+ if (!del_gid(ib_dev, port, table, ix, false))
+ deleted = true;
+ write_unlock_irq(&table->rwlock);
mutex_unlock(&table->lock);
+
+ if (deleted)
+ dispatch_gid_change_event(ib_dev, port);
+
return 0;
}
@@ -351,18 +359,14 @@ static int __ib_cache_gid_get(struct ib_device *ib_dev, u8 port, int index,
{
struct ib_gid_table **ports_table = ib_dev->cache.gid_cache;
struct ib_gid_table *table;
- unsigned long flags;
table = ports_table[port - rdma_start_port(ib_dev)];
if (index < 0 || index >= table->sz)
return -EINVAL;
- read_lock_irqsave(&table->data_vec[index].lock, flags);
- if (table->data_vec[index].props & GID_TABLE_ENTRY_INVALID) {
- read_unlock_irqrestore(&table->data_vec[index].lock, flags);
+ if (table->data_vec[index].props & GID_TABLE_ENTRY_INVALID)
return -EAGAIN;
- }
memcpy(gid, &table->data_vec[index].gid, sizeof(*gid));
if (attr) {
@@ -371,7 +375,6 @@ static int __ib_cache_gid_get(struct ib_device *ib_dev, u8 port, int index,
dev_hold(attr->ndev);
}
- read_unlock_irqrestore(&table->data_vec[index].lock, flags);
return 0;
}
@@ -385,17 +388,21 @@ static int _ib_cache_gid_table_find(struct ib_device *ib_dev,
struct ib_gid_table *table;
u8 p;
int local_index;
+ unsigned long flags;
for (p = 0; p < ib_dev->phys_port_cnt; p++) {
table = ports_table[p];
+ read_lock_irqsave(&table->rwlock, flags);
local_index = find_gid(table, gid, val, false, mask);
if (local_index >= 0) {
if (index)
*index = local_index;
if (port)
*port = p + rdma_start_port(ib_dev);
+ read_unlock_irqrestore(&table->rwlock, flags);
return 0;
}
+ read_unlock_irqrestore(&table->rwlock, flags);
}
return -ENOENT;
@@ -426,6 +433,7 @@ int ib_find_cached_gid_by_port(struct ib_device *ib_dev,
struct ib_gid_table *table;
unsigned long mask = GID_ATTR_FIND_MASK_GID;
struct ib_gid_attr val = {.ndev = ndev};
+ unsigned long flags;
if (port < rdma_start_port(ib_dev) ||
port > rdma_end_port(ib_dev))
@@ -436,13 +444,16 @@ int ib_find_cached_gid_by_port(struct ib_device *ib_dev,
if (ndev)
mask |= GID_ATTR_FIND_MASK_NETDEV;
+ read_lock_irqsave(&table->rwlock, flags);
local_index = find_gid(table, gid, &val, false, mask);
if (local_index >= 0) {
if (index)
*index = local_index;
+ read_unlock_irqrestore(&table->rwlock, flags);
return 0;
}
+ read_unlock_irqrestore(&table->rwlock, flags);
return -ENOENT;
}
EXPORT_SYMBOL(ib_find_cached_gid_by_port);
@@ -479,6 +490,7 @@ static int ib_cache_gid_find_by_filter(struct ib_device *ib_dev,
struct ib_gid_table **ports_table = ib_dev->cache.gid_cache;
struct ib_gid_table *table;
unsigned int i;
+ unsigned long flags;
bool found = false;
if (!ports_table)
@@ -491,11 +503,10 @@ static int ib_cache_gid_find_by_filter(struct ib_device *ib_dev,
table = ports_table[port - rdma_start_port(ib_dev)];
+ read_lock_irqsave(&table->rwlock, flags);
for (i = 0; i < table->sz; i++) {
struct ib_gid_attr attr;
- unsigned long flags;
- read_lock_irqsave(&table->data_vec[i].lock, flags);
if (table->data_vec[i].props & GID_TABLE_ENTRY_INVALID)
goto next;
@@ -508,11 +519,10 @@ static int ib_cache_gid_find_by_filter(struct ib_device *ib_dev,
found = true;
next:
- read_unlock_irqrestore(&table->data_vec[i].lock, flags);
-
if (found)
break;
}
+ read_unlock_irqrestore(&table->rwlock, flags);
if (!found)
return -ENOENT;
@@ -524,9 +534,9 @@ next:
static struct ib_gid_table *alloc_gid_table(int sz)
{
- unsigned int i;
struct ib_gid_table *table =
kzalloc(sizeof(struct ib_gid_table), GFP_KERNEL);
+
if (!table)
return NULL;
@@ -537,9 +547,7 @@ static struct ib_gid_table *alloc_gid_table(int sz)
mutex_init(&table->lock);
table->sz = sz;
-
- for (i = 0; i < sz; i++)
- rwlock_init(&table->data_vec[i].lock);
+ rwlock_init(&table->rwlock);
return table;
@@ -560,17 +568,24 @@ static void cleanup_gid_table_port(struct ib_device *ib_dev, u8 port,
struct ib_gid_table *table)
{
int i;
+ bool deleted = false;
if (!table)
return;
+ write_lock_irq(&table->rwlock);
for (i = 0; i < table->sz; ++i) {
if (memcmp(&table->data_vec[i].gid, &zgid,
sizeof(table->data_vec[i].gid)))
- del_gid(ib_dev, port, table, i,
- table->data_vec[i].props &
- GID_ATTR_FIND_MASK_DEFAULT);
+ if (!del_gid(ib_dev, port, table, i,
+ table->data_vec[i].props &
+ GID_ATTR_FIND_MASK_DEFAULT))
+ deleted = true;
}
+ write_unlock_irq(&table->rwlock);
+
+ if (deleted)
+ dispatch_gid_change_event(ib_dev, port);
}
void ib_cache_gid_set_default_gid(struct ib_device *ib_dev, u8 port,
@@ -592,6 +607,7 @@ void ib_cache_gid_set_default_gid(struct ib_device *ib_dev, u8 port,
gid_attr.ndev = ndev;
mutex_lock(&table->lock);
+ write_lock_irq(&table->rwlock);
ix = find_gid(table, NULL, NULL, true, GID_ATTR_FIND_MASK_DEFAULT);
/* Coudn't find default GID location */
@@ -604,23 +620,31 @@ void ib_cache_gid_set_default_gid(struct ib_device *ib_dev, u8 port,
!memcmp(&gid_attr, ¤t_gid_attr, sizeof(gid_attr)))
goto unlock;
- if ((memcmp(¤t_gid, &zgid, sizeof(current_gid)) ||
- memcmp(¤t_gid_attr, &zattr,
- sizeof(current_gid_attr))) &&
- del_gid(ib_dev, port, table, ix, true)) {
- pr_warn("ib_cache_gid: can't delete index %d for default gid %pI6\n",
- ix, gid.raw);
- goto unlock;
+ if (memcmp(¤t_gid, &zgid, sizeof(current_gid)) ||
+ memcmp(¤t_gid_attr, &zattr,
+ sizeof(current_gid_attr))) {
+ if (del_gid(ib_dev, port, table, ix, true)) {
+ pr_warn("ib_cache_gid: can't delete index %d for default gid %pI6\n",
+ ix, gid.raw);
+ goto unlock;
+ } else {
+ dispatch_gid_change_event(ib_dev, port);
+ }
}
- if (mode == IB_CACHE_GID_DEFAULT_MODE_SET)
- if (add_gid(ib_dev, port, table, ix, &gid, &gid_attr, true))
+ if (mode == IB_CACHE_GID_DEFAULT_MODE_SET) {
+ if (add_gid(ib_dev, port, table, ix, &gid, &gid_attr, true)) {
pr_warn("ib_cache_gid: unable to add default gid %pI6\n",
gid.raw);
+ } else {
+ dispatch_gid_change_event(ib_dev, port);
+ }
+ }
unlock:
if (current_gid_attr.ndev)
dev_put(current_gid_attr.ndev);
+ write_unlock_irq(&table->rwlock);
mutex_unlock(&table->lock);
}
@@ -735,10 +759,19 @@ int ib_get_cached_gid(struct ib_device *device,
union ib_gid *gid,
struct ib_gid_attr *gid_attr)
{
+ int res;
+ unsigned long flags;
+ struct ib_gid_table **ports_table = device->cache.gid_cache;
+ struct ib_gid_table *table = ports_table[port_num - rdma_start_port(device)];
+
if (port_num < rdma_start_port(device) || port_num > rdma_end_port(device))
return -EINVAL;
- return __ib_cache_gid_get(device, port_num, index, gid, gid_attr);
+ read_lock_irqsave(&table->rwlock, flags);
+ res = __ib_cache_gid_get(device, port_num, index, gid, gid_attr);
+ read_unlock_irqrestore(&table->rwlock, flags);
+
+ return res;
}
EXPORT_SYMBOL(ib_get_cached_gid);
@@ -963,10 +996,12 @@ static void ib_cache_update(struct ib_device *device,
device->cache.pkey_cache[port - rdma_start_port(device)] = pkey_cache;
if (!use_roce_gid_table) {
+ write_lock(&table->rwlock);
for (i = 0; i < gid_cache->table_len; i++) {
modify_gid(device, port, table, i, gid_cache->table + i,
&zattr, false);
}
+ write_unlock(&table->rwlock);
}
device->cache.lmc_cache[port - rdma_start_port(device)] = tprops->lmc;
--
2.1.0
--
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