From: Wen Gu <guwen@linux.alibaba.com>
To: wintera@linux.ibm.com, twinkler@linux.ibm.com, hca@linux.ibm.com,
gor@linux.ibm.com, agordeev@linux.ibm.com, davem@davemloft.net,
edumazet@google.com, kuba@kernel.org, pabeni@redhat.com,
wenjia@linux.ibm.com, jaka@linux.ibm.com
Cc: borntraeger@linux.ibm.com, svens@linux.ibm.com,
alibuda@linux.alibaba.com, tonylu@linux.alibaba.com,
guwen@linux.alibaba.com, linux-kernel@vger.kernel.org,
linux-s390@vger.kernel.org, netdev@vger.kernel.org
Subject: [PATCH net-next v7 11/11] net/smc: implement DMB-merged operations of loopback-ism
Date: Sun, 28 Apr 2024 14:07:38 +0800 [thread overview]
Message-ID: <20240428060738.60843-12-guwen@linux.alibaba.com> (raw)
In-Reply-To: <20240428060738.60843-1-guwen@linux.alibaba.com>
This implements operations related to merging sndbuf with peer DMB in
loopback-ism. The DMB won't be freed until no sndbuf is attached to it.
Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Reviewed-and-tested-by: Jan Karcher <jaka@linux.ibm.com>
---
net/smc/smc_loopback.c | 120 +++++++++++++++++++++++++++++++++++------
net/smc/smc_loopback.h | 3 ++
2 files changed, 108 insertions(+), 15 deletions(-)
diff --git a/net/smc/smc_loopback.c b/net/smc/smc_loopback.c
index 94a57f4ee3f9..3c5f64ca4115 100644
--- a/net/smc/smc_loopback.c
+++ b/net/smc/smc_loopback.c
@@ -20,6 +20,7 @@
#include "smc_loopback.h"
#define SMC_LO_V2_CAPABLE 0x1 /* loopback-ism acts as ISMv2 */
+#define SMC_LO_SUPPORT_NOCOPY 0x1
#define SMC_DMA_ADDR_INVALID (~(dma_addr_t)0)
static const char smc_lo_dev_name[] = "loopback-ism";
@@ -81,6 +82,7 @@ static int smc_lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb,
goto err_node;
}
dmb_node->dma_addr = SMC_DMA_ADDR_INVALID;
+ refcount_set(&dmb_node->refcnt, 1);
again:
/* add new dmb into hash table */
@@ -94,6 +96,7 @@ static int smc_lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb,
}
hash_add(ldev->dmb_ht, &dmb_node->list, dmb_node->token);
write_unlock_bh(&ldev->dmb_ht_lock);
+ atomic_inc(&ldev->dmb_cnt);
dmb->sba_idx = dmb_node->sba_idx;
dmb->dmb_tok = dmb_node->token;
@@ -110,13 +113,29 @@ static int smc_lo_register_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb,
return rc;
}
+static void __smc_lo_unregister_dmb(struct smc_lo_dev *ldev,
+ struct smc_lo_dmb_node *dmb_node)
+{
+ /* remove dmb from hash table */
+ write_lock_bh(&ldev->dmb_ht_lock);
+ hash_del(&dmb_node->list);
+ write_unlock_bh(&ldev->dmb_ht_lock);
+
+ clear_bit(dmb_node->sba_idx, ldev->sba_idx_mask);
+ kvfree(dmb_node->cpu_addr);
+ kfree(dmb_node);
+
+ if (atomic_dec_and_test(&ldev->dmb_cnt))
+ wake_up(&ldev->ldev_release);
+}
+
static int smc_lo_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
{
struct smc_lo_dmb_node *dmb_node = NULL, *tmp_node;
struct smc_lo_dev *ldev = smcd->priv;
- /* remove dmb from hash table */
- write_lock_bh(&ldev->dmb_ht_lock);
+ /* find dmb from hash table */
+ read_lock_bh(&ldev->dmb_ht_lock);
hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb->dmb_tok) {
if (tmp_node->token == dmb->dmb_tok) {
dmb_node = tmp_node;
@@ -124,16 +143,76 @@ static int smc_lo_unregister_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
}
}
if (!dmb_node) {
- write_unlock_bh(&ldev->dmb_ht_lock);
+ read_unlock_bh(&ldev->dmb_ht_lock);
return -EINVAL;
}
- hash_del(&dmb_node->list);
- write_unlock_bh(&ldev->dmb_ht_lock);
+ read_unlock_bh(&ldev->dmb_ht_lock);
- clear_bit(dmb_node->sba_idx, ldev->sba_idx_mask);
- kfree(dmb_node->cpu_addr);
- kfree(dmb_node);
+ if (refcount_dec_and_test(&dmb_node->refcnt))
+ __smc_lo_unregister_dmb(ldev, dmb_node);
+ return 0;
+}
+
+static int smc_lo_support_dmb_nocopy(struct smcd_dev *smcd)
+{
+ return SMC_LO_SUPPORT_NOCOPY;
+}
+
+static int smc_lo_attach_dmb(struct smcd_dev *smcd, struct smcd_dmb *dmb)
+{
+ struct smc_lo_dmb_node *dmb_node = NULL, *tmp_node;
+ struct smc_lo_dev *ldev = smcd->priv;
+
+ /* find dmb_node according to dmb->dmb_tok */
+ read_lock_bh(&ldev->dmb_ht_lock);
+ hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb->dmb_tok) {
+ if (tmp_node->token == dmb->dmb_tok) {
+ dmb_node = tmp_node;
+ break;
+ }
+ }
+ if (!dmb_node) {
+ read_unlock_bh(&ldev->dmb_ht_lock);
+ return -EINVAL;
+ }
+ read_unlock_bh(&ldev->dmb_ht_lock);
+
+ if (!refcount_inc_not_zero(&dmb_node->refcnt))
+ /* the dmb is being unregistered, but has
+ * not been removed from the hash table.
+ */
+ return -EINVAL;
+ /* provide dmb information */
+ dmb->sba_idx = dmb_node->sba_idx;
+ dmb->dmb_tok = dmb_node->token;
+ dmb->cpu_addr = dmb_node->cpu_addr;
+ dmb->dma_addr = dmb_node->dma_addr;
+ dmb->dmb_len = dmb_node->len;
+ return 0;
+}
+
+static int smc_lo_detach_dmb(struct smcd_dev *smcd, u64 token)
+{
+ struct smc_lo_dmb_node *dmb_node = NULL, *tmp_node;
+ struct smc_lo_dev *ldev = smcd->priv;
+
+ /* find dmb_node according to dmb->dmb_tok */
+ read_lock_bh(&ldev->dmb_ht_lock);
+ hash_for_each_possible(ldev->dmb_ht, tmp_node, list, token) {
+ if (tmp_node->token == token) {
+ dmb_node = tmp_node;
+ break;
+ }
+ }
+ if (!dmb_node) {
+ read_unlock_bh(&ldev->dmb_ht_lock);
+ return -EINVAL;
+ }
+ read_unlock_bh(&ldev->dmb_ht_lock);
+
+ if (refcount_dec_and_test(&dmb_node->refcnt))
+ __smc_lo_unregister_dmb(ldev, dmb_node);
return 0;
}
@@ -145,6 +224,12 @@ static int smc_lo_move_data(struct smcd_dev *smcd, u64 dmb_tok,
struct smc_lo_dev *ldev = smcd->priv;
struct smc_connection *conn;
+ if (!sf)
+ /* since sndbuf is merged with peer DMB, there is
+ * no need to copy data from sndbuf to peer DMB.
+ */
+ return 0;
+
read_lock_bh(&ldev->dmb_ht_lock);
hash_for_each_possible(ldev->dmb_ht, tmp_node, list, dmb_tok) {
if (tmp_node->token == dmb_tok) {
@@ -159,13 +244,10 @@ static int smc_lo_move_data(struct smcd_dev *smcd, u64 dmb_tok,
memcpy((char *)rmb_node->cpu_addr + offset, data, size);
read_unlock_bh(&ldev->dmb_ht_lock);
- if (sf) {
- conn = smcd->conn[rmb_node->sba_idx];
- if (conn && !conn->killed)
- tasklet_schedule(&conn->rx_tsklet);
- else
- return -EPIPE;
- }
+ conn = smcd->conn[rmb_node->sba_idx];
+ if (!conn || conn->killed)
+ return -EPIPE;
+ tasklet_schedule(&conn->rx_tsklet);
return 0;
}
@@ -197,6 +279,9 @@ static const struct smcd_ops lo_ops = {
.query_remote_gid = smc_lo_query_rgid,
.register_dmb = smc_lo_register_dmb,
.unregister_dmb = smc_lo_unregister_dmb,
+ .support_dmb_nocopy = smc_lo_support_dmb_nocopy,
+ .attach_dmb = smc_lo_attach_dmb,
+ .detach_dmb = smc_lo_detach_dmb,
.add_vlan_id = NULL,
.del_vlan_id = NULL,
.set_vlan_required = NULL,
@@ -275,12 +360,17 @@ static int smc_lo_dev_init(struct smc_lo_dev *ldev)
smc_lo_generate_ids(ldev);
rwlock_init(&ldev->dmb_ht_lock);
hash_init(ldev->dmb_ht);
+ atomic_set(&ldev->dmb_cnt, 0);
+ init_waitqueue_head(&ldev->ldev_release);
+
return smcd_lo_register_dev(ldev);
}
static void smc_lo_dev_exit(struct smc_lo_dev *ldev)
{
smcd_lo_unregister_dev(ldev);
+ if (atomic_read(&ldev->dmb_cnt))
+ wait_event(ldev->ldev_release, !atomic_read(&ldev->dmb_cnt));
}
static void smc_lo_dev_release(struct device *dev)
diff --git a/net/smc/smc_loopback.h b/net/smc/smc_loopback.h
index b8206338309f..6dd4292dae56 100644
--- a/net/smc/smc_loopback.h
+++ b/net/smc/smc_loopback.h
@@ -30,6 +30,7 @@ struct smc_lo_dmb_node {
u32 sba_idx;
void *cpu_addr;
dma_addr_t dma_addr;
+ refcount_t refcnt;
};
struct smc_lo_dev {
@@ -37,9 +38,11 @@ struct smc_lo_dev {
struct device dev;
u16 chid;
struct smcd_gid local_gid;
+ atomic_t dmb_cnt;
rwlock_t dmb_ht_lock;
DECLARE_BITMAP(sba_idx_mask, SMC_LO_MAX_DMBS);
DECLARE_HASHTABLE(dmb_ht, SMC_LO_DMBS_HASH_BITS);
+ wait_queue_head_t ldev_release;
};
int smc_loopback_init(void);
--
2.32.0.3.g01195cf9f
next prev parent reply other threads:[~2024-04-28 6:08 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-28 6:07 [PATCH net-next v7 00/11] net/smc: SMC intra-OS shortcut with loopback-ism Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 01/11] net/smc: decouple ism_client from SMC-D DMB registration Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 02/11] net/smc: introduce loopback-ism for SMC intra-OS shortcut Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 03/11] net/smc: implement ID-related operations of loopback-ism Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 04/11] net/smc: implement DMB-related " Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 05/11] net/smc: mark optional smcd_ops and check for support when called Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 06/11] net/smc: ignore loopback-ism when dumping SMC-D devices Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 07/11] net/smc: register loopback-ism into SMC-D device list Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 08/11] net/smc: add operations to merge sndbuf with peer DMB Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 09/11] net/smc: {at|de}tach sndbuf to peer DMB if supported Wen Gu
2024-04-28 6:07 ` [PATCH net-next v7 10/11] net/smc: adapt cursor update when sndbuf and peer DMB are merged Wen Gu
2024-04-28 6:07 ` Wen Gu [this message]
2024-04-28 15:49 ` [PATCH net-next v7 00/11] net/smc: SMC intra-OS shortcut with loopback-ism Cong Wang
2024-05-07 14:34 ` Wen Gu
2024-05-07 16:10 ` Cong Wang
2024-05-08 3:48 ` Wen Gu
2024-05-08 6:39 ` Tony Lu
2024-04-30 11:40 ` patchwork-bot+netdevbpf
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