linux-next/net/rxrpc/txbuf.c
David Howells 08d55d7cf3 rxrpc: Don't allocate a txbuf for an ACK transmission
Don't allocate an rxrpc_txbuf struct for an ACK transmission.  There's now
no need as the memory to hold the ACK content is allocated with a page frag
allocator.  The allocation and freeing of a txbuf is just unnecessary
overhead.

Signed-off-by: David Howells <dhowells@redhat.com>
cc: Marc Dionne <marc.dionne@auristor.com>
cc: linux-afs@lists.infradead.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-12-09 13:48:31 -08:00

122 lines
3.1 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 a data transmission buffer.
*/
struct rxrpc_txbuf *rxrpc_alloc_data_txbuf(struct rxrpc_call *call, size_t data_size,
size_t data_align, gfp_t gfp)
{
struct rxrpc_wire_header *whdr;
struct rxrpc_txbuf *txb;
size_t total, hoff;
void *buf;
txb = kzalloc(sizeof(*txb), gfp);
if (!txb)
return NULL;
hoff = round_up(sizeof(*whdr), data_align) - sizeof(*whdr);
total = hoff + sizeof(*whdr) + data_size;
data_align = umax(data_align, L1_CACHE_BYTES);
mutex_lock(&call->conn->tx_data_alloc_lock);
buf = page_frag_alloc_align(&call->conn->tx_data_alloc, total, gfp,
data_align);
mutex_unlock(&call->conn->tx_data_alloc_lock);
if (!buf) {
kfree(txb);
return NULL;
}
whdr = buf + hoff;
refcount_set(&txb->ref, 1);
txb->call_debug_id = call->debug_id;
txb->debug_id = atomic_inc_return(&rxrpc_txbuf_debug_ids);
txb->alloc_size = data_size;
txb->space = data_size;
txb->offset = sizeof(*whdr);
txb->flags = call->conn->out_clientflag;
txb->seq = call->send_top + 1;
txb->nr_kvec = 1;
txb->kvec[0].iov_base = whdr;
txb->kvec[0].iov_len = sizeof(*whdr);
whdr->epoch = htonl(call->conn->proto.epoch);
whdr->cid = htonl(call->cid);
whdr->callNumber = htonl(call->call_id);
whdr->seq = htonl(txb->seq);
whdr->type = RXRPC_PACKET_TYPE_DATA;
whdr->flags = 0;
whdr->userStatus = 0;
whdr->securityIndex = call->security_ix;
whdr->_rsvd = 0;
whdr->serviceId = htons(call->dest_srx.srx_service);
trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, 1,
rxrpc_txbuf_alloc_data);
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 rxrpc_txbuf *txb)
{
int i;
trace_rxrpc_txbuf(txb->debug_id, txb->call_debug_id, txb->seq, 0,
rxrpc_txbuf_free);
for (i = 0; i < txb->nr_kvec; i++)
if (txb->kvec[i].iov_base &&
!is_zero_pfn(page_to_pfn(virt_to_page(txb->kvec[i].iov_base))))
page_frag_free(txb->kvec[i].iov_base);
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)
rxrpc_free_txbuf(txb);
}
}