[PATCH 3/3] Infiniband: don't use task_struct.tgid in make_cm_node()

[PATCH 3/3] Infiniband: don't use task_struct.tgid in make_cm_node()

[Pavel Emelyanov]

The task_struct->tgid field is about to become deprecated, due to
pid namespaces make tasks have many pids, not one. There is one
place using it left to fix in infiniband - the make_cm_node().

This function uses the task tgid just to generate a session id,
so it's perfectly safe to use appropriate wrapper - task_tgid_nr().

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>

---

 drivers/infiniband/hw/nes/nes_cm.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 39adb26..7a06156 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1077,7 +1077,8 @@ static struct nes_cm_node *make_cm_node(struct nes_cm_core *cm_core,
 	/* get a unique session ID , add thread_id to an upcounter to handle race */
 	atomic_inc(&cm_core->node_cnt);
 	atomic_inc(&cm_core->session_id);
-	cm_node->session_id = (u32)(atomic_read(&cm_core->session_id) + current->tgid);
+	cm_node->session_id = (u32)(atomic_read(&cm_core->session_id) +
+			task_tgid_nr(current));
 	cm_node->conn_type = cm_info->conn_type;
 	cm_node->apbvt_set = 0;
 	cm_node->accept_pend = 0;
@@ -1606,7 +1607,8 @@ static struct nes_cm_listener *mini_cm_listen(struct nes_cm_core *cm_core,
 	atomic_inc(&cm_core->node_cnt);
 	atomic_inc(&cm_core->session_id);
 
-	listener->session_id = (u32)(atomic_read(&cm_core->session_id) + current->tgid);
+	listener->session_id = (u32)(atomic_read(&cm_core->session_id) +
+			task_tgid_nr(current));
 	listener->conn_type = cm_info->conn_type;
 	listener->backlog = cm_info->backlog;
 	listener->listener_state = NES_CM_LISTENER_ACTIVE_STATE;

RE: [PATCH 3/3] Infiniband: don't use task_struct.tgid in make_cm_node()

[Glenn Streiff]

Acked-by Glenn Streiff <gstreiff@neteffect.com>

> From: Roland Dreier [mailto:rdreier@cisco.com]
> The patch
> below compiles and links fine for me, so is the simplest fix?  (I
> don't think hardware is looking at session_id behind our back, is it?)
> 
> diff --git a/drivers/infiniband/hw/nes/nes_cm.c 
> b/drivers/infiniband/hw/nes/nes_cm.c
> index c1a85f3..31a28e9 100644
> --- a/drivers/infiniband/hw/nes/nes_cm.c
> +++ b/drivers/infiniband/hw/nes/nes_cm.c
> @@ -365,7 +365,6 @@ static void print_core(struct nes_cm_core *core)
>  	if (!core)
>  		return;
>  	nes_debug(NES_DBG_CM, 
> "---------------------------------------------\n");
> -	nes_debug(NES_DBG_CM, "Session ID    : %u \n", 
> atomic_read(&core->session_id));
>  
>  	nes_debug(NES_DBG_CM, "State         : %u \n",  core->state);
>  
> @@ -1100,8 +1099,6 @@ static struct nes_cm_node 
> *make_cm_node(struct nes_cm_core *cm_core,
>  	cm_node->tcp_cntxt.rcv_nxt = 0;
>  	/* get a unique session ID , add thread_id to an 
> upcounter to handle race */
>  	atomic_inc(&cm_core->node_cnt);
> -	atomic_inc(&cm_core->session_id);
> -	cm_node->session_id = 
> (u32)(atomic_read(&cm_core->session_id) + current->tgid);
>  	cm_node->conn_type = cm_info->conn_type;
>  	cm_node->apbvt_set = 0;
>  	cm_node->accept_pend = 0;
> @@ -1628,9 +1625,7 @@ static struct nes_cm_listener 
> *mini_cm_listen(struct nes_cm_core *cm_core,
>  	listener->cm_core = cm_core;
>  	listener->nesvnic = nesvnic;
>  	atomic_inc(&cm_core->node_cnt);
> -	atomic_inc(&cm_core->session_id);
>  
> -	listener->session_id = 
> (u32)(atomic_read(&cm_core->session_id) + current->tgid);
>  	listener->conn_type = cm_info->conn_type;
>  	listener->backlog = cm_info->backlog;
>  	listener->listener_state = NES_CM_LISTENER_ACTIVE_STATE;
> @@ -1943,7 +1938,6 @@ static struct nes_cm_core 
> *nes_cm_alloc_core(void)
>  	cm_core->state = NES_CM_STATE_INITED;
>  	cm_core->free_tx_pkt_max = NES_CM_DEFAULT_FREE_PKTS;
>  
> -	atomic_set(&cm_core->session_id, 0);
>  	atomic_set(&cm_core->events_posted, 0);
>  
>  	/* init the packet lists */
> diff --git a/drivers/infiniband/hw/nes/nes_cm.h 
> b/drivers/infiniband/hw/nes/nes_cm.h
> index 980fb67..7717cb2 100644
> --- a/drivers/infiniband/hw/nes/nes_cm.h
> +++ b/drivers/infiniband/hw/nes/nes_cm.h
> @@ -225,7 +225,6 @@ enum nes_cm_listener_state {
>  
>  struct nes_cm_listener {
>  	struct list_head           list;
> -	u64                        session_id;
>  	struct nes_cm_core         *cm_core;
>  	u8                         loc_mac[ETH_ALEN];
>  	nes_addr_t                 loc_addr;
> @@ -242,7 +241,6 @@ struct nes_cm_listener {
>  
>  /* per connection node and node state information */
>  struct nes_cm_node {
> -	u64                       session_id;
>  	u32                       hashkey;
>  
>  	nes_addr_t                loc_addr, rem_addr;
> @@ -327,7 +325,6 @@ struct nes_cm_event {
>  
>  struct nes_cm_core {
>  	enum nes_cm_node_state  state;
> -	atomic_t                session_id;
>  
>  	atomic_t                listen_node_cnt;
>  	struct nes_cm_node      listen_list;
>