linux/net/rds/ib_cm.c
Santosh Shilimkar f4f943c958 RDS: IB: ack more receive completions to improve performance
For better performance, we split the receive completion IRQ handler. That
lets us acknowledge several WCE events in one call. We also limit the WC
to max 32 to avoid latency. Acknowledging several completions in one call
instead of several calls each time will provide better performance since
less mutual exclusion locks are being performed.

In next patch, send completion is also split which re-uses the poll_cq()
and hence the code is moved to ib_cm.c

Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
2015-10-05 11:19:01 -07:00

880 lines
25 KiB
C

/*
* Copyright (c) 2006 Oracle. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*
*/
#include <linux/kernel.h>
#include <linux/in.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/ratelimit.h>
#include "rds.h"
#include "ib.h"
/*
* Set the selected protocol version
*/
static void rds_ib_set_protocol(struct rds_connection *conn, unsigned int version)
{
conn->c_version = version;
}
/*
* Set up flow control
*/
static void rds_ib_set_flow_control(struct rds_connection *conn, u32 credits)
{
struct rds_ib_connection *ic = conn->c_transport_data;
if (rds_ib_sysctl_flow_control && credits != 0) {
/* We're doing flow control */
ic->i_flowctl = 1;
rds_ib_send_add_credits(conn, credits);
} else {
ic->i_flowctl = 0;
}
}
/*
* Tune RNR behavior. Without flow control, we use a rather
* low timeout, but not the absolute minimum - this should
* be tunable.
*
* We already set the RNR retry count to 7 (which is the
* smallest infinite number :-) above.
* If flow control is off, we want to change this back to 0
* so that we learn quickly when our credit accounting is
* buggy.
*
* Caller passes in a qp_attr pointer - don't waste stack spacv
* by allocation this twice.
*/
static void
rds_ib_tune_rnr(struct rds_ib_connection *ic, struct ib_qp_attr *attr)
{
int ret;
attr->min_rnr_timer = IB_RNR_TIMER_000_32;
ret = ib_modify_qp(ic->i_cm_id->qp, attr, IB_QP_MIN_RNR_TIMER);
if (ret)
printk(KERN_NOTICE "ib_modify_qp(IB_QP_MIN_RNR_TIMER): err=%d\n", -ret);
}
/*
* Connection established.
* We get here for both outgoing and incoming connection.
*/
void rds_ib_cm_connect_complete(struct rds_connection *conn, struct rdma_cm_event *event)
{
const struct rds_ib_connect_private *dp = NULL;
struct rds_ib_connection *ic = conn->c_transport_data;
struct ib_qp_attr qp_attr;
int err;
if (event->param.conn.private_data_len >= sizeof(*dp)) {
dp = event->param.conn.private_data;
/* make sure it isn't empty data */
if (dp->dp_protocol_major) {
rds_ib_set_protocol(conn,
RDS_PROTOCOL(dp->dp_protocol_major,
dp->dp_protocol_minor));
rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
}
}
if (conn->c_version < RDS_PROTOCOL(3,1)) {
printk(KERN_NOTICE "RDS/IB: Connection to %pI4 version %u.%u failed,"
" no longer supported\n",
&conn->c_faddr,
RDS_PROTOCOL_MAJOR(conn->c_version),
RDS_PROTOCOL_MINOR(conn->c_version));
rds_conn_destroy(conn);
return;
} else {
printk(KERN_NOTICE "RDS/IB: connected to %pI4 version %u.%u%s\n",
&conn->c_faddr,
RDS_PROTOCOL_MAJOR(conn->c_version),
RDS_PROTOCOL_MINOR(conn->c_version),
ic->i_flowctl ? ", flow control" : "");
}
/*
* Init rings and fill recv. this needs to wait until protocol negotiation
* is complete, since ring layout is different from 3.0 to 3.1.
*/
rds_ib_send_init_ring(ic);
rds_ib_recv_init_ring(ic);
/* Post receive buffers - as a side effect, this will update
* the posted credit count. */
rds_ib_recv_refill(conn, 1, GFP_KERNEL);
/* Tune RNR behavior */
rds_ib_tune_rnr(ic, &qp_attr);
qp_attr.qp_state = IB_QPS_RTS;
err = ib_modify_qp(ic->i_cm_id->qp, &qp_attr, IB_QP_STATE);
if (err)
printk(KERN_NOTICE "ib_modify_qp(IB_QP_STATE, RTS): err=%d\n", err);
/* update ib_device with this local ipaddr */
err = rds_ib_update_ipaddr(ic->rds_ibdev, conn->c_laddr);
if (err)
printk(KERN_ERR "rds_ib_update_ipaddr failed (%d)\n",
err);
/* If the peer gave us the last packet it saw, process this as if
* we had received a regular ACK. */
if (dp) {
/* dp structure start is not guaranteed to be 8 bytes aligned.
* Since dp_ack_seq is 64-bit extended load operations can be
* used so go through get_unaligned to avoid unaligned errors.
*/
__be64 dp_ack_seq = get_unaligned(&dp->dp_ack_seq);
if (dp_ack_seq)
rds_send_drop_acked(conn, be64_to_cpu(dp_ack_seq),
NULL);
}
rds_connect_complete(conn);
}
static void rds_ib_cm_fill_conn_param(struct rds_connection *conn,
struct rdma_conn_param *conn_param,
struct rds_ib_connect_private *dp,
u32 protocol_version,
u32 max_responder_resources,
u32 max_initiator_depth)
{
struct rds_ib_connection *ic = conn->c_transport_data;
struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
memset(conn_param, 0, sizeof(struct rdma_conn_param));
conn_param->responder_resources =
min_t(u32, rds_ibdev->max_responder_resources, max_responder_resources);
conn_param->initiator_depth =
min_t(u32, rds_ibdev->max_initiator_depth, max_initiator_depth);
conn_param->retry_count = min_t(unsigned int, rds_ib_retry_count, 7);
conn_param->rnr_retry_count = 7;
if (dp) {
memset(dp, 0, sizeof(*dp));
dp->dp_saddr = conn->c_laddr;
dp->dp_daddr = conn->c_faddr;
dp->dp_protocol_major = RDS_PROTOCOL_MAJOR(protocol_version);
dp->dp_protocol_minor = RDS_PROTOCOL_MINOR(protocol_version);
dp->dp_protocol_minor_mask = cpu_to_be16(RDS_IB_SUPPORTED_PROTOCOLS);
dp->dp_ack_seq = rds_ib_piggyb_ack(ic);
/* Advertise flow control */
if (ic->i_flowctl) {
unsigned int credits;
credits = IB_GET_POST_CREDITS(atomic_read(&ic->i_credits));
dp->dp_credit = cpu_to_be32(credits);
atomic_sub(IB_SET_POST_CREDITS(credits), &ic->i_credits);
}
conn_param->private_data = dp;
conn_param->private_data_len = sizeof(*dp);
}
}
static void rds_ib_cq_event_handler(struct ib_event *event, void *data)
{
rdsdebug("event %u (%s) data %p\n",
event->event, ib_event_msg(event->event), data);
}
/* Plucking the oldest entry from the ring can be done concurrently with
* the thread refilling the ring. Each ring operation is protected by
* spinlocks and the transient state of refilling doesn't change the
* recording of which entry is oldest.
*
* This relies on IB only calling one cq comp_handler for each cq so that
* there will only be one caller of rds_recv_incoming() per RDS connection.
*/
static void rds_ib_cq_comp_handler_recv(struct ib_cq *cq, void *context)
{
struct rds_connection *conn = context;
struct rds_ib_connection *ic = conn->c_transport_data;
rdsdebug("conn %p cq %p\n", conn, cq);
rds_ib_stats_inc(s_ib_evt_handler_call);
tasklet_schedule(&ic->i_recv_tasklet);
}
static void poll_cq(struct rds_ib_connection *ic, struct ib_cq *cq,
struct ib_wc *wcs,
struct rds_ib_ack_state *ack_state)
{
int nr;
int i;
struct ib_wc *wc;
while ((nr = ib_poll_cq(cq, RDS_IB_WC_MAX, wcs)) > 0) {
for (i = 0; i < nr; i++) {
wc = wcs + i;
rdsdebug("wc wr_id 0x%llx status %u byte_len %u imm_data %u\n",
(unsigned long long)wc->wr_id, wc->status,
wc->byte_len, be32_to_cpu(wc->ex.imm_data));
rds_ib_recv_cqe_handler(ic, wc, ack_state);
}
}
}
static void rds_ib_tasklet_fn_recv(unsigned long data)
{
struct rds_ib_connection *ic = (struct rds_ib_connection *)data;
struct rds_connection *conn = ic->conn;
struct rds_ib_device *rds_ibdev = ic->rds_ibdev;
struct rds_ib_ack_state state;
BUG_ON(!rds_ibdev);
rds_ib_stats_inc(s_ib_tasklet_call);
memset(&state, 0, sizeof(state));
poll_cq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
poll_cq(ic, ic->i_recv_cq, ic->i_recv_wc, &state);
if (state.ack_next_valid)
rds_ib_set_ack(ic, state.ack_next, state.ack_required);
if (state.ack_recv_valid && state.ack_recv > ic->i_ack_recv) {
rds_send_drop_acked(conn, state.ack_recv, NULL);
ic->i_ack_recv = state.ack_recv;
}
if (rds_conn_up(conn))
rds_ib_attempt_ack(ic);
}
static void rds_ib_qp_event_handler(struct ib_event *event, void *data)
{
struct rds_connection *conn = data;
struct rds_ib_connection *ic = conn->c_transport_data;
rdsdebug("conn %p ic %p event %u (%s)\n", conn, ic, event->event,
ib_event_msg(event->event));
switch (event->event) {
case IB_EVENT_COMM_EST:
rdma_notify(ic->i_cm_id, IB_EVENT_COMM_EST);
break;
default:
rdsdebug("Fatal QP Event %u (%s) "
"- connection %pI4->%pI4, reconnecting\n",
event->event, ib_event_msg(event->event),
&conn->c_laddr, &conn->c_faddr);
rds_conn_drop(conn);
break;
}
}
/*
* This needs to be very careful to not leave IS_ERR pointers around for
* cleanup to trip over.
*/
static int rds_ib_setup_qp(struct rds_connection *conn)
{
struct rds_ib_connection *ic = conn->c_transport_data;
struct ib_device *dev = ic->i_cm_id->device;
struct ib_qp_init_attr attr;
struct ib_cq_init_attr cq_attr = {};
struct rds_ib_device *rds_ibdev;
int ret;
/*
* It's normal to see a null device if an incoming connection races
* with device removal, so we don't print a warning.
*/
rds_ibdev = rds_ib_get_client_data(dev);
if (!rds_ibdev)
return -EOPNOTSUPP;
/* add the conn now so that connection establishment has the dev */
rds_ib_add_conn(rds_ibdev, conn);
if (rds_ibdev->max_wrs < ic->i_send_ring.w_nr + 1)
rds_ib_ring_resize(&ic->i_send_ring, rds_ibdev->max_wrs - 1);
if (rds_ibdev->max_wrs < ic->i_recv_ring.w_nr + 1)
rds_ib_ring_resize(&ic->i_recv_ring, rds_ibdev->max_wrs - 1);
/* Protection domain and memory range */
ic->i_pd = rds_ibdev->pd;
cq_attr.cqe = ic->i_send_ring.w_nr + 1;
ic->i_send_cq = ib_create_cq(dev, rds_ib_send_cq_comp_handler,
rds_ib_cq_event_handler, conn,
&cq_attr);
if (IS_ERR(ic->i_send_cq)) {
ret = PTR_ERR(ic->i_send_cq);
ic->i_send_cq = NULL;
rdsdebug("ib_create_cq send failed: %d\n", ret);
goto out;
}
cq_attr.cqe = ic->i_recv_ring.w_nr;
ic->i_recv_cq = ib_create_cq(dev, rds_ib_cq_comp_handler_recv,
rds_ib_cq_event_handler, conn,
&cq_attr);
if (IS_ERR(ic->i_recv_cq)) {
ret = PTR_ERR(ic->i_recv_cq);
ic->i_recv_cq = NULL;
rdsdebug("ib_create_cq recv failed: %d\n", ret);
goto out;
}
ret = ib_req_notify_cq(ic->i_send_cq, IB_CQ_NEXT_COMP);
if (ret) {
rdsdebug("ib_req_notify_cq send failed: %d\n", ret);
goto out;
}
ret = ib_req_notify_cq(ic->i_recv_cq, IB_CQ_SOLICITED);
if (ret) {
rdsdebug("ib_req_notify_cq recv failed: %d\n", ret);
goto out;
}
/* XXX negotiate max send/recv with remote? */
memset(&attr, 0, sizeof(attr));
attr.event_handler = rds_ib_qp_event_handler;
attr.qp_context = conn;
/* + 1 to allow for the single ack message */
attr.cap.max_send_wr = ic->i_send_ring.w_nr + 1;
attr.cap.max_recv_wr = ic->i_recv_ring.w_nr + 1;
attr.cap.max_send_sge = rds_ibdev->max_sge;
attr.cap.max_recv_sge = RDS_IB_RECV_SGE;
attr.sq_sig_type = IB_SIGNAL_REQ_WR;
attr.qp_type = IB_QPT_RC;
attr.send_cq = ic->i_send_cq;
attr.recv_cq = ic->i_recv_cq;
/*
* XXX this can fail if max_*_wr is too large? Are we supposed
* to back off until we get a value that the hardware can support?
*/
ret = rdma_create_qp(ic->i_cm_id, ic->i_pd, &attr);
if (ret) {
rdsdebug("rdma_create_qp failed: %d\n", ret);
goto out;
}
ic->i_send_hdrs = ib_dma_alloc_coherent(dev,
ic->i_send_ring.w_nr *
sizeof(struct rds_header),
&ic->i_send_hdrs_dma, GFP_KERNEL);
if (!ic->i_send_hdrs) {
ret = -ENOMEM;
rdsdebug("ib_dma_alloc_coherent send failed\n");
goto out;
}
ic->i_recv_hdrs = ib_dma_alloc_coherent(dev,
ic->i_recv_ring.w_nr *
sizeof(struct rds_header),
&ic->i_recv_hdrs_dma, GFP_KERNEL);
if (!ic->i_recv_hdrs) {
ret = -ENOMEM;
rdsdebug("ib_dma_alloc_coherent recv failed\n");
goto out;
}
ic->i_ack = ib_dma_alloc_coherent(dev, sizeof(struct rds_header),
&ic->i_ack_dma, GFP_KERNEL);
if (!ic->i_ack) {
ret = -ENOMEM;
rdsdebug("ib_dma_alloc_coherent ack failed\n");
goto out;
}
ic->i_sends = vzalloc_node(ic->i_send_ring.w_nr * sizeof(struct rds_ib_send_work),
ibdev_to_node(dev));
if (!ic->i_sends) {
ret = -ENOMEM;
rdsdebug("send allocation failed\n");
goto out;
}
ic->i_recvs = vzalloc_node(ic->i_recv_ring.w_nr * sizeof(struct rds_ib_recv_work),
ibdev_to_node(dev));
if (!ic->i_recvs) {
ret = -ENOMEM;
rdsdebug("recv allocation failed\n");
goto out;
}
rds_ib_recv_init_ack(ic);
rdsdebug("conn %p pd %p cq %p %p\n", conn, ic->i_pd,
ic->i_send_cq, ic->i_recv_cq);
out:
rds_ib_dev_put(rds_ibdev);
return ret;
}
static u32 rds_ib_protocol_compatible(struct rdma_cm_event *event)
{
const struct rds_ib_connect_private *dp = event->param.conn.private_data;
u16 common;
u32 version = 0;
/*
* rdma_cm private data is odd - when there is any private data in the
* request, we will be given a pretty large buffer without telling us the
* original size. The only way to tell the difference is by looking at
* the contents, which are initialized to zero.
* If the protocol version fields aren't set, this is a connection attempt
* from an older version. This could could be 3.0 or 2.0 - we can't tell.
* We really should have changed this for OFED 1.3 :-(
*/
/* Be paranoid. RDS always has privdata */
if (!event->param.conn.private_data_len) {
printk(KERN_NOTICE "RDS incoming connection has no private data, "
"rejecting\n");
return 0;
}
/* Even if len is crap *now* I still want to check it. -ASG */
if (event->param.conn.private_data_len < sizeof (*dp) ||
dp->dp_protocol_major == 0)
return RDS_PROTOCOL_3_0;
common = be16_to_cpu(dp->dp_protocol_minor_mask) & RDS_IB_SUPPORTED_PROTOCOLS;
if (dp->dp_protocol_major == 3 && common) {
version = RDS_PROTOCOL_3_0;
while ((common >>= 1) != 0)
version++;
} else
printk_ratelimited(KERN_NOTICE "RDS: Connection from %pI4 using incompatible protocol version %u.%u\n",
&dp->dp_saddr,
dp->dp_protocol_major,
dp->dp_protocol_minor);
return version;
}
int rds_ib_cm_handle_connect(struct rdma_cm_id *cm_id,
struct rdma_cm_event *event)
{
__be64 lguid = cm_id->route.path_rec->sgid.global.interface_id;
__be64 fguid = cm_id->route.path_rec->dgid.global.interface_id;
const struct rds_ib_connect_private *dp = event->param.conn.private_data;
struct rds_ib_connect_private dp_rep;
struct rds_connection *conn = NULL;
struct rds_ib_connection *ic = NULL;
struct rdma_conn_param conn_param;
u32 version;
int err = 1, destroy = 1;
/* Check whether the remote protocol version matches ours. */
version = rds_ib_protocol_compatible(event);
if (!version)
goto out;
rdsdebug("saddr %pI4 daddr %pI4 RDSv%u.%u lguid 0x%llx fguid "
"0x%llx\n", &dp->dp_saddr, &dp->dp_daddr,
RDS_PROTOCOL_MAJOR(version), RDS_PROTOCOL_MINOR(version),
(unsigned long long)be64_to_cpu(lguid),
(unsigned long long)be64_to_cpu(fguid));
/* RDS/IB is not currently netns aware, thus init_net */
conn = rds_conn_create(&init_net, dp->dp_daddr, dp->dp_saddr,
&rds_ib_transport, GFP_KERNEL);
if (IS_ERR(conn)) {
rdsdebug("rds_conn_create failed (%ld)\n", PTR_ERR(conn));
conn = NULL;
goto out;
}
/*
* The connection request may occur while the
* previous connection exist, e.g. in case of failover.
* But as connections may be initiated simultaneously
* by both hosts, we have a random backoff mechanism -
* see the comment above rds_queue_reconnect()
*/
mutex_lock(&conn->c_cm_lock);
if (!rds_conn_transition(conn, RDS_CONN_DOWN, RDS_CONN_CONNECTING)) {
if (rds_conn_state(conn) == RDS_CONN_UP) {
rdsdebug("incoming connect while connecting\n");
rds_conn_drop(conn);
rds_ib_stats_inc(s_ib_listen_closed_stale);
} else
if (rds_conn_state(conn) == RDS_CONN_CONNECTING) {
/* Wait and see - our connect may still be succeeding */
rds_ib_stats_inc(s_ib_connect_raced);
}
goto out;
}
ic = conn->c_transport_data;
rds_ib_set_protocol(conn, version);
rds_ib_set_flow_control(conn, be32_to_cpu(dp->dp_credit));
/* If the peer gave us the last packet it saw, process this as if
* we had received a regular ACK. */
if (dp->dp_ack_seq)
rds_send_drop_acked(conn, be64_to_cpu(dp->dp_ack_seq), NULL);
BUG_ON(cm_id->context);
BUG_ON(ic->i_cm_id);
ic->i_cm_id = cm_id;
cm_id->context = conn;
/* We got halfway through setting up the ib_connection, if we
* fail now, we have to take the long route out of this mess. */
destroy = 0;
err = rds_ib_setup_qp(conn);
if (err) {
rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", err);
goto out;
}
rds_ib_cm_fill_conn_param(conn, &conn_param, &dp_rep, version,
event->param.conn.responder_resources,
event->param.conn.initiator_depth);
/* rdma_accept() calls rdma_reject() internally if it fails */
err = rdma_accept(cm_id, &conn_param);
if (err)
rds_ib_conn_error(conn, "rdma_accept failed (%d)\n", err);
out:
if (conn)
mutex_unlock(&conn->c_cm_lock);
if (err)
rdma_reject(cm_id, NULL, 0);
return destroy;
}
int rds_ib_cm_initiate_connect(struct rdma_cm_id *cm_id)
{
struct rds_connection *conn = cm_id->context;
struct rds_ib_connection *ic = conn->c_transport_data;
struct rdma_conn_param conn_param;
struct rds_ib_connect_private dp;
int ret;
/* If the peer doesn't do protocol negotiation, we must
* default to RDSv3.0 */
rds_ib_set_protocol(conn, RDS_PROTOCOL_3_0);
ic->i_flowctl = rds_ib_sysctl_flow_control; /* advertise flow control */
ret = rds_ib_setup_qp(conn);
if (ret) {
rds_ib_conn_error(conn, "rds_ib_setup_qp failed (%d)\n", ret);
goto out;
}
rds_ib_cm_fill_conn_param(conn, &conn_param, &dp, RDS_PROTOCOL_VERSION,
UINT_MAX, UINT_MAX);
ret = rdma_connect(cm_id, &conn_param);
if (ret)
rds_ib_conn_error(conn, "rdma_connect failed (%d)\n", ret);
out:
/* Beware - returning non-zero tells the rdma_cm to destroy
* the cm_id. We should certainly not do it as long as we still
* "own" the cm_id. */
if (ret) {
if (ic->i_cm_id == cm_id)
ret = 0;
}
return ret;
}
int rds_ib_conn_connect(struct rds_connection *conn)
{
struct rds_ib_connection *ic = conn->c_transport_data;
struct sockaddr_in src, dest;
int ret;
/* XXX I wonder what affect the port space has */
/* delegate cm event handler to rdma_transport */
ic->i_cm_id = rdma_create_id(rds_rdma_cm_event_handler, conn,
RDMA_PS_TCP, IB_QPT_RC);
if (IS_ERR(ic->i_cm_id)) {
ret = PTR_ERR(ic->i_cm_id);
ic->i_cm_id = NULL;
rdsdebug("rdma_create_id() failed: %d\n", ret);
goto out;
}
rdsdebug("created cm id %p for conn %p\n", ic->i_cm_id, conn);
src.sin_family = AF_INET;
src.sin_addr.s_addr = (__force u32)conn->c_laddr;
src.sin_port = (__force u16)htons(0);
dest.sin_family = AF_INET;
dest.sin_addr.s_addr = (__force u32)conn->c_faddr;
dest.sin_port = (__force u16)htons(RDS_PORT);
ret = rdma_resolve_addr(ic->i_cm_id, (struct sockaddr *)&src,
(struct sockaddr *)&dest,
RDS_RDMA_RESOLVE_TIMEOUT_MS);
if (ret) {
rdsdebug("addr resolve failed for cm id %p: %d\n", ic->i_cm_id,
ret);
rdma_destroy_id(ic->i_cm_id);
ic->i_cm_id = NULL;
}
out:
return ret;
}
/*
* This is so careful about only cleaning up resources that were built up
* so that it can be called at any point during startup. In fact it
* can be called multiple times for a given connection.
*/
void rds_ib_conn_shutdown(struct rds_connection *conn)
{
struct rds_ib_connection *ic = conn->c_transport_data;
int err = 0;
rdsdebug("cm %p pd %p cq %p %p qp %p\n", ic->i_cm_id,
ic->i_pd, ic->i_send_cq, ic->i_recv_cq,
ic->i_cm_id ? ic->i_cm_id->qp : NULL);
if (ic->i_cm_id) {
struct ib_device *dev = ic->i_cm_id->device;
rdsdebug("disconnecting cm %p\n", ic->i_cm_id);
err = rdma_disconnect(ic->i_cm_id);
if (err) {
/* Actually this may happen quite frequently, when
* an outgoing connect raced with an incoming connect.
*/
rdsdebug("failed to disconnect, cm: %p err %d\n",
ic->i_cm_id, err);
}
/*
* We want to wait for tx and rx completion to finish
* before we tear down the connection, but we have to be
* careful not to get stuck waiting on a send ring that
* only has unsignaled sends in it. We've shutdown new
* sends before getting here so by waiting for signaled
* sends to complete we're ensured that there will be no
* more tx processing.
*/
wait_event(rds_ib_ring_empty_wait,
rds_ib_ring_empty(&ic->i_recv_ring) &&
(atomic_read(&ic->i_signaled_sends) == 0));
tasklet_kill(&ic->i_recv_tasklet);
/* first destroy the ib state that generates callbacks */
if (ic->i_cm_id->qp)
rdma_destroy_qp(ic->i_cm_id);
if (ic->i_send_cq)
ib_destroy_cq(ic->i_send_cq);
if (ic->i_recv_cq)
ib_destroy_cq(ic->i_recv_cq);
/* then free the resources that ib callbacks use */
if (ic->i_send_hdrs)
ib_dma_free_coherent(dev,
ic->i_send_ring.w_nr *
sizeof(struct rds_header),
ic->i_send_hdrs,
ic->i_send_hdrs_dma);
if (ic->i_recv_hdrs)
ib_dma_free_coherent(dev,
ic->i_recv_ring.w_nr *
sizeof(struct rds_header),
ic->i_recv_hdrs,
ic->i_recv_hdrs_dma);
if (ic->i_ack)
ib_dma_free_coherent(dev, sizeof(struct rds_header),
ic->i_ack, ic->i_ack_dma);
if (ic->i_sends)
rds_ib_send_clear_ring(ic);
if (ic->i_recvs)
rds_ib_recv_clear_ring(ic);
rdma_destroy_id(ic->i_cm_id);
/*
* Move connection back to the nodev list.
*/
if (ic->rds_ibdev)
rds_ib_remove_conn(ic->rds_ibdev, conn);
ic->i_cm_id = NULL;
ic->i_pd = NULL;
ic->i_send_cq = NULL;
ic->i_recv_cq = NULL;
ic->i_send_hdrs = NULL;
ic->i_recv_hdrs = NULL;
ic->i_ack = NULL;
}
BUG_ON(ic->rds_ibdev);
/* Clear pending transmit */
if (ic->i_data_op) {
struct rds_message *rm;
rm = container_of(ic->i_data_op, struct rds_message, data);
rds_message_put(rm);
ic->i_data_op = NULL;
}
/* Clear the ACK state */
clear_bit(IB_ACK_IN_FLIGHT, &ic->i_ack_flags);
#ifdef KERNEL_HAS_ATOMIC64
atomic64_set(&ic->i_ack_next, 0);
#else
ic->i_ack_next = 0;
#endif
ic->i_ack_recv = 0;
/* Clear flow control state */
ic->i_flowctl = 0;
atomic_set(&ic->i_credits, 0);
rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
if (ic->i_ibinc) {
rds_inc_put(&ic->i_ibinc->ii_inc);
ic->i_ibinc = NULL;
}
vfree(ic->i_sends);
ic->i_sends = NULL;
vfree(ic->i_recvs);
ic->i_recvs = NULL;
}
int rds_ib_conn_alloc(struct rds_connection *conn, gfp_t gfp)
{
struct rds_ib_connection *ic;
unsigned long flags;
int ret;
/* XXX too lazy? */
ic = kzalloc(sizeof(struct rds_ib_connection), gfp);
if (!ic)
return -ENOMEM;
ret = rds_ib_recv_alloc_caches(ic);
if (ret) {
kfree(ic);
return ret;
}
INIT_LIST_HEAD(&ic->ib_node);
tasklet_init(&ic->i_recv_tasklet, rds_ib_tasklet_fn_recv,
(unsigned long) ic);
mutex_init(&ic->i_recv_mutex);
#ifndef KERNEL_HAS_ATOMIC64
spin_lock_init(&ic->i_ack_lock);
#endif
atomic_set(&ic->i_signaled_sends, 0);
/*
* rds_ib_conn_shutdown() waits for these to be emptied so they
* must be initialized before it can be called.
*/
rds_ib_ring_init(&ic->i_send_ring, rds_ib_sysctl_max_send_wr);
rds_ib_ring_init(&ic->i_recv_ring, rds_ib_sysctl_max_recv_wr);
ic->conn = conn;
conn->c_transport_data = ic;
spin_lock_irqsave(&ib_nodev_conns_lock, flags);
list_add_tail(&ic->ib_node, &ib_nodev_conns);
spin_unlock_irqrestore(&ib_nodev_conns_lock, flags);
rdsdebug("conn %p conn ic %p\n", conn, conn->c_transport_data);
return 0;
}
/*
* Free a connection. Connection must be shut down and not set for reconnect.
*/
void rds_ib_conn_free(void *arg)
{
struct rds_ib_connection *ic = arg;
spinlock_t *lock_ptr;
rdsdebug("ic %p\n", ic);
/*
* Conn is either on a dev's list or on the nodev list.
* A race with shutdown() or connect() would cause problems
* (since rds_ibdev would change) but that should never happen.
*/
lock_ptr = ic->rds_ibdev ? &ic->rds_ibdev->spinlock : &ib_nodev_conns_lock;
spin_lock_irq(lock_ptr);
list_del(&ic->ib_node);
spin_unlock_irq(lock_ptr);
rds_ib_recv_free_caches(ic);
kfree(ic);
}
/*
* An error occurred on the connection
*/
void
__rds_ib_conn_error(struct rds_connection *conn, const char *fmt, ...)
{
va_list ap;
rds_conn_drop(conn);
va_start(ap, fmt);
vprintk(fmt, ap);
va_end(ap);
}