mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-14 06:24:53 +08:00
b30d61f4b1
call->tx_buffer is now only accessed within the I/O thread (->tx_sendmsg is the way sendmsg passes packets to the I/O thread) so there's no need to lock around it. Signed-off-by: David Howells <dhowells@redhat.com> cc: Marc Dionne <marc.dionne@auristor.com> cc: linux-afs@lists.infradead.org
135 lines
3.5 KiB
C
135 lines
3.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/* RxRPC Tx data buffering.
|
|
*
|
|
* Copyright (C) 2022 Red Hat, Inc. All Rights Reserved.
|
|
* Written by David Howells (dhowells@redhat.com)
|
|
*/
|
|
|
|
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
|
|
|
|
#include <linux/slab.h>
|
|
#include "ar-internal.h"
|
|
|
|
static atomic_t rxrpc_txbuf_debug_ids;
|
|
atomic_t rxrpc_nr_txbuf;
|
|
|
|
/*
|
|
* Allocate and partially initialise an I/O request structure.
|
|
*/
|
|
struct rxrpc_txbuf *rxrpc_alloc_txbuf(struct rxrpc_call *call, u8 packet_type,
|
|
gfp_t gfp)
|
|
{
|
|
struct rxrpc_txbuf *txb;
|
|
|
|
txb = kmalloc(sizeof(*txb), gfp);
|
|
if (txb) {
|
|
INIT_LIST_HEAD(&txb->call_link);
|
|
INIT_LIST_HEAD(&txb->tx_link);
|
|
refcount_set(&txb->ref, 1);
|
|
txb->call_debug_id = call->debug_id;
|
|
txb->debug_id = atomic_inc_return(&rxrpc_txbuf_debug_ids);
|
|
txb->space = sizeof(txb->data);
|
|
txb->len = 0;
|
|
txb->offset = 0;
|
|
txb->flags = 0;
|
|
txb->ack_why = 0;
|
|
txb->seq = call->tx_prepared + 1;
|
|
txb->wire.epoch = htonl(call->conn->proto.epoch);
|
|
txb->wire.cid = htonl(call->cid);
|
|
txb->wire.callNumber = htonl(call->call_id);
|
|
txb->wire.seq = htonl(txb->seq);
|
|
txb->wire.type = packet_type;
|
|
txb->wire.flags = call->conn->out_clientflag;
|
|
txb->wire.userStatus = 0;
|
|
txb->wire.securityIndex = call->security_ix;
|
|
txb->wire._rsvd = 0;
|
|
txb->wire.serviceId = htons(call->dest_srx.srx_service);
|
|
|
|
trace_rxrpc_txbuf(txb->debug_id,
|
|
txb->call_debug_id, txb->seq, 1,
|
|
packet_type == RXRPC_PACKET_TYPE_DATA ?
|
|
rxrpc_txbuf_alloc_data :
|
|
rxrpc_txbuf_alloc_ack);
|
|
atomic_inc(&rxrpc_nr_txbuf);
|
|
}
|
|
|
|
return txb;
|
|
}
|
|
|
|
void rxrpc_get_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what)
|
|
{
|
|
int r;
|
|
|
|
__refcount_inc(&txb->ref, &r);
|
|
trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, r + 1, what);
|
|
}
|
|
|
|
void rxrpc_see_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what)
|
|
{
|
|
int r = refcount_read(&txb->ref);
|
|
|
|
trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, r, what);
|
|
}
|
|
|
|
static void rxrpc_free_txbuf(struct rcu_head *rcu)
|
|
{
|
|
struct rxrpc_txbuf *txb = container_of(rcu, struct rxrpc_txbuf, rcu);
|
|
|
|
trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, 0,
|
|
rxrpc_txbuf_free);
|
|
kfree(txb);
|
|
atomic_dec(&rxrpc_nr_txbuf);
|
|
}
|
|
|
|
void rxrpc_put_txbuf(struct rxrpc_txbuf *txb, enum rxrpc_txbuf_trace what)
|
|
{
|
|
unsigned int debug_id, call_debug_id;
|
|
rxrpc_seq_t seq;
|
|
bool dead;
|
|
int r;
|
|
|
|
if (txb) {
|
|
debug_id = txb->debug_id;
|
|
call_debug_id = txb->call_debug_id;
|
|
seq = txb->seq;
|
|
dead = __refcount_dec_and_test(&txb->ref, &r);
|
|
trace_rxrpc_txbuf(debug_id, call_debug_id, seq, r - 1, what);
|
|
if (dead)
|
|
call_rcu(&txb->rcu, rxrpc_free_txbuf);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Shrink the transmit buffer.
|
|
*/
|
|
void rxrpc_shrink_call_tx_buffer(struct rxrpc_call *call)
|
|
{
|
|
struct rxrpc_txbuf *txb;
|
|
rxrpc_seq_t hard_ack = smp_load_acquire(&call->acks_hard_ack);
|
|
bool wake = false;
|
|
|
|
_enter("%x/%x/%x", call->tx_bottom, call->acks_hard_ack, call->tx_top);
|
|
|
|
while ((txb = list_first_entry_or_null(&call->tx_buffer,
|
|
struct rxrpc_txbuf, call_link))) {
|
|
hard_ack = smp_load_acquire(&call->acks_hard_ack);
|
|
if (before(hard_ack, txb->seq))
|
|
break;
|
|
|
|
if (txb->seq != call->tx_bottom + 1)
|
|
rxrpc_see_txbuf(txb, rxrpc_txbuf_see_out_of_step);
|
|
ASSERTCMP(txb->seq, ==, call->tx_bottom + 1);
|
|
smp_store_release(&call->tx_bottom, call->tx_bottom + 1);
|
|
list_del_rcu(&txb->call_link);
|
|
|
|
trace_rxrpc_txqueue(call, rxrpc_txqueue_dequeue);
|
|
|
|
rxrpc_put_txbuf(txb, rxrpc_txbuf_put_rotated);
|
|
if (after(call->acks_hard_ack, call->tx_bottom + 128))
|
|
wake = true;
|
|
}
|
|
|
|
if (wake)
|
|
wake_up(&call->waitq);
|
|
}
|