Re: [PATCH 2/2] Staging: lustre: lnet: lib-move return of an errno should typically be negative (ie: return -EAGAIN)

["Dilger, Andreas" <andreas.dilger@intel.com>]

On 2015/10/22, 22:30, "Nilesh Kokane" <nilesh.kokane05@gmail.com> wrote:
>Fixed- Return of an errno should typically be negative (ie: return
>-EAGAIN)

Nak. Please do not change these function return values.  They are
converted as necessary by the callers before returning to userspace, but
allow the code to distinguish between errors generated internally or from
lower networking layers.

As you will note, many of them are explicitly annotated with comments that
they are returning positive values.  The patch as it stands would totally
break the code.

Cheers, Andreas

>Signed-off-by: Nilesh Kokane <Nilesh.Kokane05@gmail.com>
>---
> drivers/staging/lustre/lnet/lnet/lib-move.c | 22 +++++++++++-----------
> 1 file changed, 11 insertions(+), 11 deletions(-)
>
>diff --git a/drivers/staging/lustre/lnet/lnet/lib-move.c
>b/drivers/staging/lustre/lnet/lnet/lib-move.c
>index 433faae..10f886f 100644
>--- a/drivers/staging/lustre/lnet/lnet/lib-move.c
>+++ b/drivers/staging/lustre/lnet/lnet/lib-move.c
>@@ -808,7 +808,7 @@ lnet_post_send_locked(lnet_msg_t *msg, int do_send)
> 			lnet_finalize(ni, msg, -EHOSTUNREACH);
> 
> 		lnet_net_lock(cpt);
>-		return EHOSTUNREACH;
>+		return -EHOSTUNREACH;
> 	}
> 
> 	if (msg->msg_md != NULL &&
>@@ -821,7 +821,7 @@ lnet_post_send_locked(lnet_msg_t *msg, int do_send)
> 			lnet_finalize(ni, msg, -ECANCELED);
> 
> 		lnet_net_lock(cpt);
>-		return ECANCELED;
>+		return -ECANCELED;
> 	}
> 
> 	if (!msg->msg_peertxcredit) {
>@@ -838,7 +838,7 @@ lnet_post_send_locked(lnet_msg_t *msg, int do_send)
> 		if (lp->lp_txcredits < 0) {
> 			msg->msg_tx_delayed = 1;
> 			list_add_tail(&msg->msg_list, &lp->lp_txq);
>-			return EAGAIN;
>+			return -EAGAIN;
> 		}
> 	}
> 
>@@ -855,7 +855,7 @@ lnet_post_send_locked(lnet_msg_t *msg, int do_send)
> 		if (tq->tq_credits < 0) {
> 			msg->msg_tx_delayed = 1;
> 			list_add_tail(&msg->msg_list, &tq->tq_delayed);
>-			return EAGAIN;
>+			return -EAGAIN;
> 		}
> 	}
> 
>@@ -922,7 +922,7 @@ lnet_post_routed_recv_locked(lnet_msg_t *msg, int
>do_recv)
> 			LASSERT(msg->msg_rx_ready_delay);
> 			msg->msg_rx_delayed = 1;
> 			list_add_tail(&msg->msg_list, &lp->lp_rtrq);
>-			return EAGAIN;
>+			return -EAGAIN;
> 		}
> 	}
> 
>@@ -942,7 +942,7 @@ lnet_post_routed_recv_locked(lnet_msg_t *msg, int
>do_recv)
> 			LASSERT(msg->msg_rx_ready_delay);
> 			msg->msg_rx_delayed = 1;
> 			list_add_tail(&msg->msg_list, &rbp->rbp_msgs);
>-			return EAGAIN;
>+			return -EAGAIN;
> 		}
> 	}
> 
>@@ -1426,7 +1426,7 @@ lnet_parse_put(lnet_ni_t *ni, lnet_msg_t *msg)
> 			libcfs_id2str(info.mi_id), info.mi_portal,
> 			info.mi_mbits, info.mi_roffset, info.mi_rlength, rc);
> 
>-		return ENOENT;	/* +ve: OK but no match */
>+		return -ENOENT;	/* +ve: OK but no match */
> 	}
> }
> 
>@@ -1457,7 +1457,7 @@ lnet_parse_get(lnet_ni_t *ni, lnet_msg_t *msg, int
>rdma_get)
> 		CNETERR("Dropping GET from %s portal %d match %llu offset %d length
>%d\n",
> 			libcfs_id2str(info.mi_id), info.mi_portal,
> 			info.mi_mbits, info.mi_roffset, info.mi_rlength);
>-		return ENOENT;	/* +ve: OK but no match */
>+		return -ENOENT;	/* +ve: OK but no match */
> 	}
> 
> 	LASSERT(rc == LNET_MATCHMD_OK);
>@@ -1524,7 +1524,7 @@ lnet_parse_reply(lnet_ni_t *ni, lnet_msg_t *msg)
> 			       md->md_me->me_portal);
> 
> 		lnet_res_unlock(cpt);
>-		return ENOENT;		  /* +ve: OK but no match */
>+		return -ENOENT;		  /* +ve: OK but no match */
> 	}
> 
> 	LASSERT(md->md_offset == 0);
>@@ -1539,7 +1539,7 @@ lnet_parse_reply(lnet_ni_t *ni, lnet_msg_t *msg)
> 			rlength, hdr->msg.reply.dst_wmd.wh_object_cookie,
> 			mlength);
> 		lnet_res_unlock(cpt);
>-		return ENOENT;	  /* +ve: OK but no match */
>+		return -ENOENT;	  /* +ve: OK but no match */
> 	}
> 
> 	CDEBUG(D_NET, "%s: Reply from %s of length %d/%d into md %#llx\n",
>@@ -1592,7 +1592,7 @@ lnet_parse_ack(lnet_ni_t *ni, lnet_msg_t *msg)
> 			       md->md_me->me_portal);
> 
> 		lnet_res_unlock(cpt);
>-		return ENOENT;		  /* +ve! */
>+		return -ENOENT;		  /* +ve! */
> 	}
> 
> 	CDEBUG(D_NET, "%s: ACK from %s into md %#llx\n",
>-- 
>1.9.1
>
>


Cheers, Andreas
-- 
Andreas Dilger

Lustre Software Architect
Intel High Performance Data Division