[Devel] [PATCH RHEL9 COMMIT] Revert "fs/fuse/kio: tidy up RPC_AFFINITY_RSS"

[Konstantin Khorenko]

The commit is pushed to "branch-rh9-5.14.0-427.55.1.vz9.82.x-ovz" and will appear at git at bitbucket.org:openvz/vzkernel.git
after rh9-5.14.0-427.55.1.vz9.82.4
------>
commit 7176e5bda1c6891b6e05a3f88d70f6ae34b12634
Author: Konstantin Khorenko <khorenko at virtuozzo.com>
Date:   Tue Jul 8 16:20:15 2025 +0200

    Revert "fs/fuse/kio: tidy up RPC_AFFINITY_RSS"
    
    This reverts commit 3f286d2b5f406c2d5325d14d3d4a4204e7fd010e.
    
    We'll have another and better commit solving the problem:
      [PATCH VZ9 v2] fs/fuse kio: do not set RPC affinity from a workequeue worker
    
    https://virtuozzo.atlassian.net/browse/VSTOR-109481
    
    Signed-off-by: Konstantin Khorenko <khorenko at virtuozzo.com>
    
    Feature: vStorage
---
 fs/fuse/kio/pcs/pcs_rdma_io.c |  1 -
 fs/fuse/kio/pcs/pcs_rpc.c     | 25 +++++++++----------------
 fs/fuse/kio/pcs/pcs_rpc.h     |  1 -
 fs/fuse/kio/pcs/pcs_sock_io.c |  5 +++--
 4 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/fs/fuse/kio/pcs/pcs_rdma_io.c b/fs/fuse/kio/pcs/pcs_rdma_io.c
index 1c464e0e60f3e..582504e054e19 100644
--- a/fs/fuse/kio/pcs/pcs_rdma_io.c
+++ b/fs/fuse/kio/pcs/pcs_rdma_io.c
@@ -1110,7 +1110,6 @@ static void pcs_rdma_cq_comp_handler(struct ib_cq *cq, void *private)
 
 	set_bit(PCS_RDMA_IO_CQE, &rio->io_flags);
 	wake_up(&rio->waitq);
-	ep->rx_cpu = smp_processor_id();
 	pcs_rpc_kick_queue(ep);
 }
 
diff --git a/fs/fuse/kio/pcs/pcs_rpc.c b/fs/fuse/kio/pcs/pcs_rpc.c
index f15d0c3fb7cd5..4ab38b3989148 100644
--- a/fs/fuse/kio/pcs/pcs_rpc.c
+++ b/fs/fuse/kio/pcs/pcs_rpc.c
@@ -339,7 +339,6 @@ void pcs_rpc_attach_new_ep(struct pcs_rpc * ep, struct pcs_rpc_engine * eng)
 	atomic_set(&ep->netlat_cnt, 0);
 	atomic64_set(&ep->netlat_avg, 0);
 	ep->cpu = WORK_CPU_UNBOUND;
-	ep->rx_cpu = WORK_CPU_UNBOUND;
 
 	ep->gc = NULL;
 	if (eng->max_gc_index)
@@ -864,33 +863,27 @@ static void pcs_rpc_affinity(struct pcs_rpc *ep, bool was_idle)
 				ep->cpu = WORK_CPU_UNBOUND;
 			}
 			break;
-		case RPC_AFFINITY_RSS: {
-			int rx_cpu = READ_ONCE(ep->rx_cpu);
-
-			if (rx_cpu != WORK_CPU_UNBOUND && ep->cpu != rx_cpu)
-				ep->cpu = rx_cpu;
+		case RPC_AFFINITY_RSS:
+			if (!(ep->flags & PCS_RPC_F_LOCAL) && ep->addr.type != PCS_ADDRTYPE_RDMA)
+				break;
 			fallthrough;
-		}
-		case RPC_AFFINITY_FAIR_SPREAD:
-			if (ep->cpu == WORK_CPU_UNBOUND ||
-			    (time_is_before_jiffies(ep->cpu_stamp) && was_idle))
-				pcs_rpc_cpu_select(ep);
-			break;
 		case RPC_AFFINITY_RETENT:
 			/* Naive socket-to-cpu binding approach */
-			if (ep->cpu == WORK_CPU_UNBOUND ||
-			    (time_is_before_jiffies(ep->cpu_stamp) && was_idle)) {
+			if (time_is_before_jiffies(ep->cpu_stamp) && was_idle) {
 				ep->cpu_stamp = jiffies + rpc_cpu_time_slice;
 				ep->cpu = smp_processor_id();
 			}
 			break;
 		case RPC_AFFINITY_SPREAD:
-			if (ep->cpu == WORK_CPU_UNBOUND ||
-			    (time_is_before_jiffies(ep->cpu_stamp) && was_idle)) {
+			if (time_is_before_jiffies(ep->cpu_stamp) && was_idle) {
 				ep->cpu_stamp = jiffies + rpc_cpu_time_slice;
 				ep->cpu = pcs_rpc_cpu_next();
 			}
 			break;
+		case RPC_AFFINITY_FAIR_SPREAD:
+			if (time_is_before_jiffies(ep->cpu_stamp) && was_idle)
+				pcs_rpc_cpu_select(ep);
+			break;
 		default:
 			pr_err("Unknown affinity mode: %u\n", rpc_affinity_mode);
 	}
diff --git a/fs/fuse/kio/pcs/pcs_rpc.h b/fs/fuse/kio/pcs/pcs_rpc.h
index 0bafc8a742636..cb18557a3da5e 100644
--- a/fs/fuse/kio/pcs/pcs_rpc.h
+++ b/fs/fuse/kio/pcs/pcs_rpc.h
@@ -142,7 +142,6 @@ struct pcs_rpc
 	int			cpu;
 	unsigned long		cpu_stamp;
 	struct delayed_work	cpu_timer_work;	/* reset cpu affinity after being idle */
-	int			rx_cpu;
 
 	struct mutex		mutex;
 	u64			accounted;
diff --git a/fs/fuse/kio/pcs/pcs_sock_io.c b/fs/fuse/kio/pcs/pcs_sock_io.c
index 7eb231b7260d2..ac8a6ecfdb374 100644
--- a/fs/fuse/kio/pcs/pcs_sock_io.c
+++ b/fs/fuse/kio/pcs/pcs_sock_io.c
@@ -593,8 +593,9 @@ static void pcs_sk_kick_queue(struct sock *sk)
 	sio = rcu_dereference_sk_user_data(sk);
 	if (sio) {
 		struct pcs_rpc *ep = sio->netio.parent;
-		DTRACE(PEER_FMT" queue cpu=%d\n", PEER_ARGS(ep), smp_processor_id());
-		ep->rx_cpu = smp_processor_id();
+		TRACE(PEER_FMT" queue cpu=%d\n", PEER_ARGS(ep), smp_processor_id());
+		if (rpc_affinity_mode == RPC_AFFINITY_RSS && !(ep->flags & PCS_RPC_F_LOCAL))
+			ep->cpu = smp_processor_id();
 		pcs_rpc_kick_queue(ep);
 	}
 	rcu_read_unlock();