devlink: implement shared buffer occupancy monitoring interface

User needs to monitor shared buffer occupancy. For that, he issues a
snapshot command in order to instruct hardware to catch current and
maximal occupancy values, and clear command in order to clear the
historical maximal values.

Also port-pool and tc-pool-bind command response messages are extended to
carry occupancy values.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/devlink.h b/include/net/devlink.h
index e4c2747..be64218 100644 (file)
--- a/include/net/devlink.h
+++ b/include/net/devlink.h
@@ -78,6 +78,18 @@ struct devlink_ops {
                                   u16 tc_index,
                                   enum devlink_sb_pool_type pool_type,
                                   u16 pool_index, u32 threshold);
+       int (*sb_occ_snapshot)(struct devlink *devlink,
+                              unsigned int sb_index);
+       int (*sb_occ_max_clear)(struct devlink *devlink,
+                               unsigned int sb_index);
+       int (*sb_occ_port_pool_get)(struct devlink_port *devlink_port,
+                                   unsigned int sb_index, u16 pool_index,
+                                   u32 *p_cur, u32 *p_max);
+       int (*sb_occ_tc_port_bind_get)(struct devlink_port *devlink_port,
+                                      unsigned int sb_index,
+                                      u16 tc_index,
+                                      enum devlink_sb_pool_type pool_type,
+                                      u32 *p_cur, u32 *p_max);
 };
 
 static inline void *devlink_priv(struct devlink *devlink)

diff --git a/include/uapi/linux/devlink.h b/include/uapi/linux/devlink.h
index 9c1aa57..ba0073b 100644 (file)
--- a/include/uapi/linux/devlink.h
+++ b/include/uapi/linux/devlink.h
@@ -53,6 +53,10 @@ enum devlink_command {
        DEVLINK_CMD_SB_TC_POOL_BIND_NEW,
        DEVLINK_CMD_SB_TC_POOL_BIND_DEL,
 
+       /* Shared buffer occupancy monitoring commands */
+       DEVLINK_CMD_SB_OCC_SNAPSHOT,
+       DEVLINK_CMD_SB_OCC_MAX_CLEAR,
+
        /* add new commands above here */
 
        __DEVLINK_CMD_MAX,
@@ -119,6 +123,8 @@ enum devlink_attr {
        DEVLINK_ATTR_SB_POOL_THRESHOLD_TYPE,    /* u8 */
        DEVLINK_ATTR_SB_THRESHOLD,              /* u32 */
        DEVLINK_ATTR_SB_TC_INDEX,               /* u16 */
+       DEVLINK_ATTR_SB_OCC_CUR,                /* u32 */
+       DEVLINK_ATTR_SB_OCC_MAX,                /* u32 */
 
        /* add new attributes above here, update the policy in devlink.c */
 

diff --git a/net/core/devlink.c b/net/core/devlink.c
index aa0b9e1..933e8d4 100644 (file)
--- a/net/core/devlink.c
+++ b/net/core/devlink.c
@@ -280,6 +280,10 @@ devlink_sb_tc_index_get_from_info(struct devlink_sb *devlink_sb,
 #define DEVLINK_NL_FLAG_NEED_DEVLINK   BIT(0)
 #define DEVLINK_NL_FLAG_NEED_PORT      BIT(1)
 #define DEVLINK_NL_FLAG_NEED_SB                BIT(2)
+#define DEVLINK_NL_FLAG_LOCK_PORTS     BIT(3)
+       /* port is not needed but we need to ensure they don't
+        * change in the middle of command
+        */
 
 static int devlink_nl_pre_doit(const struct genl_ops *ops,
                               struct sk_buff *skb, struct genl_info *info)
@@ -306,6 +310,9 @@ static int devlink_nl_pre_doit(const struct genl_ops *ops,
                }
                info->user_ptr[0] = devlink_port;
        }
+       if (ops->internal_flags & DEVLINK_NL_FLAG_LOCK_PORTS) {
+               mutex_lock(&devlink_port_mutex);
+       }
        if (ops->internal_flags & DEVLINK_NL_FLAG_NEED_SB) {
                struct devlink_sb *devlink_sb;
 
@@ -324,7 +331,8 @@ static int devlink_nl_pre_doit(const struct genl_ops *ops,
 static void devlink_nl_post_doit(const struct genl_ops *ops,
                                 struct sk_buff *skb, struct genl_info *info)
 {
-       if (ops->internal_flags & DEVLINK_NL_FLAG_NEED_PORT)
+       if (ops->internal_flags & DEVLINK_NL_FLAG_NEED_PORT ||
+           ops->internal_flags & DEVLINK_NL_FLAG_LOCK_PORTS)
                mutex_unlock(&devlink_port_mutex);
        mutex_unlock(&devlink_mutex);
 }
@@ -942,12 +950,13 @@ static int devlink_nl_sb_port_pool_fill(struct sk_buff *msg,
                                        enum devlink_command cmd,
                                        u32 portid, u32 seq, int flags)
 {
+       const struct devlink_ops *ops = devlink->ops;
        u32 threshold;
        void *hdr;
        int err;
 
-       err = devlink->ops->sb_port_pool_get(devlink_port, devlink_sb->index,
-                                            pool_index, &threshold);
+       err = ops->sb_port_pool_get(devlink_port, devlink_sb->index,
+                                   pool_index, &threshold);
        if (err)
                return err;
 
@@ -966,6 +975,22 @@ static int devlink_nl_sb_port_pool_fill(struct sk_buff *msg,
        if (nla_put_u32(msg, DEVLINK_ATTR_SB_THRESHOLD, threshold))
                goto nla_put_failure;
 
+       if (ops->sb_occ_port_pool_get) {
+               u32 cur;
+               u32 max;
+
+               err = ops->sb_occ_port_pool_get(devlink_port, devlink_sb->index,
+                                               pool_index, &cur, &max);
+               if (err && err != -EOPNOTSUPP)
+                       return err;
+               if (!err) {
+                       if (nla_put_u32(msg, DEVLINK_ATTR_SB_OCC_CUR, cur))
+                               goto nla_put_failure;
+                       if (nla_put_u32(msg, DEVLINK_ATTR_SB_OCC_MAX, max))
+                               goto nla_put_failure;
+               }
+       }
+
        genlmsg_end(msg, hdr);
        return 0;
 
@@ -1114,14 +1139,15 @@ devlink_nl_sb_tc_pool_bind_fill(struct sk_buff *msg, struct devlink *devlink,
                                enum devlink_command cmd,
                                u32 portid, u32 seq, int flags)
 {
+       const struct devlink_ops *ops = devlink->ops;
        u16 pool_index;
        u32 threshold;
        void *hdr;
        int err;
 
-       err = devlink->ops->sb_tc_pool_bind_get(devlink_port, devlink_sb->index,
-                                               tc_index, pool_type,
-                                               &pool_index, &threshold);
+       err = ops->sb_tc_pool_bind_get(devlink_port, devlink_sb->index,
+                                      tc_index, pool_type,
+                                      &pool_index, &threshold);
        if (err)
                return err;
 
@@ -1144,6 +1170,24 @@ devlink_nl_sb_tc_pool_bind_fill(struct sk_buff *msg, struct devlink *devlink,
        if (nla_put_u32(msg, DEVLINK_ATTR_SB_THRESHOLD, threshold))
                goto nla_put_failure;
 
+       if (ops->sb_occ_tc_port_bind_get) {
+               u32 cur;
+               u32 max;
+
+               err = ops->sb_occ_tc_port_bind_get(devlink_port,
+                                                  devlink_sb->index,
+                                                  tc_index, pool_type,
+                                                  &cur, &max);
+               if (err && err != -EOPNOTSUPP)
+                       return err;
+               if (!err) {
+                       if (nla_put_u32(msg, DEVLINK_ATTR_SB_OCC_CUR, cur))
+                               goto nla_put_failure;
+                       if (nla_put_u32(msg, DEVLINK_ATTR_SB_OCC_MAX, max))
+                               goto nla_put_failure;
+               }
+       }
+
        genlmsg_end(msg, hdr);
        return 0;
 
@@ -1326,6 +1370,30 @@ static int devlink_nl_cmd_sb_tc_pool_bind_set_doit(struct sk_buff *skb,
                                           pool_index, threshold);
 }
 
+static int devlink_nl_cmd_sb_occ_snapshot_doit(struct sk_buff *skb,
+                                              struct genl_info *info)
+{
+       struct devlink *devlink = info->user_ptr[0];
+       struct devlink_sb *devlink_sb = info->user_ptr[1];
+       const struct devlink_ops *ops = devlink->ops;
+
+       if (ops && ops->sb_occ_snapshot)
+               return ops->sb_occ_snapshot(devlink, devlink_sb->index);
+       return -EOPNOTSUPP;
+}
+
+static int devlink_nl_cmd_sb_occ_max_clear_doit(struct sk_buff *skb,
+                                               struct genl_info *info)
+{
+       struct devlink *devlink = info->user_ptr[0];
+       struct devlink_sb *devlink_sb = info->user_ptr[1];
+       const struct devlink_ops *ops = devlink->ops;
+
+       if (ops && ops->sb_occ_max_clear)
+               return ops->sb_occ_max_clear(devlink, devlink_sb->index);
+       return -EOPNOTSUPP;
+}
+
 static const struct nla_policy devlink_nl_policy[DEVLINK_ATTR_MAX + 1] = {
        [DEVLINK_ATTR_BUS_NAME] = { .type = NLA_NUL_STRING },
        [DEVLINK_ATTR_DEV_NAME] = { .type = NLA_NUL_STRING },
@@ -1439,6 +1507,24 @@ static const struct genl_ops devlink_nl_ops[] = {
                .internal_flags = DEVLINK_NL_FLAG_NEED_PORT |
                                  DEVLINK_NL_FLAG_NEED_SB,
        },
+       {
+               .cmd = DEVLINK_CMD_SB_OCC_SNAPSHOT,
+               .doit = devlink_nl_cmd_sb_occ_snapshot_doit,
+               .policy = devlink_nl_policy,
+               .flags = GENL_ADMIN_PERM,
+               .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK |
+                                 DEVLINK_NL_FLAG_NEED_SB |
+                                 DEVLINK_NL_FLAG_LOCK_PORTS,
+       },
+       {
+               .cmd = DEVLINK_CMD_SB_OCC_MAX_CLEAR,
+               .doit = devlink_nl_cmd_sb_occ_max_clear_doit,
+               .policy = devlink_nl_policy,
+               .flags = GENL_ADMIN_PERM,
+               .internal_flags = DEVLINK_NL_FLAG_NEED_DEVLINK |
+                                 DEVLINK_NL_FLAG_NEED_SB |
+                                 DEVLINK_NL_FLAG_LOCK_PORTS,
+       },
 };
 
 /**