[ovs-dev] [optimize 13/26] netlink-socket: Make caller provide message receive buffers.
Ben Pfaff
blp at nicira.com
Tue Apr 17 00:18:53 UTC 2012
Typically an nl_sock client can stack-allocate the buffer for receiving
a Netlink message, which provides a performance boost.
Signed-off-by: Ben Pfaff <blp at nicira.com>
---
lib/dpif-linux.c | 25 ++++-
lib/netlink-notifier.c | 10 +-
lib/netlink-socket.c | 260 +++++++++++++++++++++++++---------------------
lib/netlink-socket.h | 20 +++--
utilities/nlmon.c | 14 +--
vswitchd/ovs-brcompatd.c | 49 ++++-----
6 files changed, 208 insertions(+), 170 deletions(-)
diff --git a/lib/dpif-linux.c b/lib/dpif-linux.c
index 94526f5..a2908cf 100644
--- a/lib/dpif-linux.c
+++ b/lib/dpif-linux.c
@@ -823,8 +823,12 @@ dpif_linux_operate__(struct dpif *dpif_, struct dpif_op **ops, size_t n_ops)
struct op_auxdata {
struct nl_transaction txn;
+
struct ofpbuf request;
uint64_t request_stub[1024 / 8];
+
+ struct ofpbuf reply;
+ uint64_t reply_stub[1024 / 8];
} auxes[MAX_OPS];
struct nl_transaction *txnsp[MAX_OPS];
@@ -843,12 +847,16 @@ dpif_linux_operate__(struct dpif *dpif_, struct dpif_op **ops, size_t n_ops)
aux->request_stub, sizeof aux->request_stub);
aux->txn.request = &aux->request;
+ ofpbuf_use_stub(&aux->reply, aux->reply_stub, sizeof aux->reply_stub);
+ aux->txn.reply = NULL;
+
switch (op->type) {
case DPIF_OP_FLOW_PUT:
put = &op->u.flow_put;
dpif_linux_init_flow_put(dpif_, put, &flow);
if (put->stats) {
flow.nlmsg_flags |= NLM_F_ECHO;
+ aux->txn.reply = &aux->reply;
}
dpif_linux_flow_to_ofpbuf(&flow, &aux->request);
break;
@@ -858,6 +866,7 @@ dpif_linux_operate__(struct dpif *dpif_, struct dpif_op **ops, size_t n_ops)
dpif_linux_init_flow_del(dpif_, del, &flow);
if (del->stats) {
flow.nlmsg_flags |= NLM_F_ECHO;
+ aux->txn.reply = &aux->reply;
}
dpif_linux_flow_to_ofpbuf(&flow, &aux->request);
break;
@@ -879,6 +888,7 @@ dpif_linux_operate__(struct dpif *dpif_, struct dpif_op **ops, size_t n_ops)
nl_sock_transact_multiple(genl_sock, txnsp, n_ops);
for (i = 0; i < n_ops; i++) {
+ struct op_auxdata *aux = &auxes[i];
struct nl_transaction *txn = &auxes[i].txn;
struct dpif_op *op = ops[i];
struct dpif_flow_put *put;
@@ -918,8 +928,8 @@ dpif_linux_operate__(struct dpif *dpif_, struct dpif_op **ops, size_t n_ops)
NOT_REACHED();
}
- ofpbuf_uninit(txn->request);
- ofpbuf_delete(txn->reply);
+ ofpbuf_uninit(&aux->request);
+ ofpbuf_uninit(&aux->reply);
}
}
@@ -1121,10 +1131,13 @@ dpif_linux_recv(struct dpif *dpif_, struct dpif_upcall *upcall)
return EAGAIN;
}
- error = nl_sock_recv(upcall_sock, &buf, false);
- if (error == EAGAIN) {
- break;
- } else if (error) {
+ buf = ofpbuf_new(2048);
+ error = nl_sock_recv(upcall_sock, buf, false);
+ if (error) {
+ ofpbuf_delete(buf);
+ if (error == EAGAIN) {
+ break;
+ }
return error;
}
diff --git a/lib/netlink-notifier.c b/lib/netlink-notifier.c
index 9446488..7ef3d6c 100644
--- a/lib/netlink-notifier.c
+++ b/lib/netlink-notifier.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2009, 2010, 2011 Nicira Networks.
+ * Copyright (c) 2009, 2010, 2011, 2012 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -164,18 +164,20 @@ nln_run(struct nln *nln)
nln->has_run = true;
for (;;) {
- struct ofpbuf *buf;
+ uint64_t buf_stub[4096 / 8];
+ struct ofpbuf buf;
int error;
+ ofpbuf_use_stub(&buf, buf_stub, sizeof buf_stub);
error = nl_sock_recv(nln->notify_sock, &buf, false);
if (!error) {
- if (nln->parse(buf, nln->change)) {
+ if (nln->parse(&buf, nln->change)) {
nln_report(nln, nln->change);
} else {
VLOG_WARN_RL(&rl, "received bad netlink message");
nln_report(nln, NULL);
}
- ofpbuf_delete(buf);
+ ofpbuf_uninit(&buf);
} else if (error == EAGAIN) {
return;
} else {
diff --git a/lib/netlink-socket.c b/lib/netlink-socket.c
index 90734c7..ab09dbc 100644
--- a/lib/netlink-socket.c
+++ b/lib/netlink-socket.c
@@ -300,32 +300,26 @@ STRESS_OPTION(
5, 1, -1, 100);
static int
-nl_sock_recv__(struct nl_sock *sock, struct ofpbuf **bufp, bool wait)
+nl_sock_recv__(struct nl_sock *sock, struct ofpbuf *buf, bool wait)
{
- /* We can't accurately predict the size of the data to be received. Most
- * received data will fit in a 2 kB buffer, so we allocate that much space.
- * In case the data is actually bigger than that, we make available enough
- * additional space to allow Netlink messages to be up to 64 kB long (a
- * reasonable figure since that's the maximum length of a Netlink
- * attribute). */
- enum { MAX_SIZE = 65536 };
- enum { HEAD_SIZE = 2048 };
- enum { TAIL_SIZE = MAX_SIZE - HEAD_SIZE };
-
+ /* We can't accurately predict the size of the data to be received. The
+ * caller is supposed to have allocated enough space in 'buf' to handle the
+ * "typical" case. To handle exceptions, we make available enough space in
+ * 'tail' to allow Netlink messages to be up to 64 kB long (a reasonable
+ * figure since that's the maximum length of a Netlink attribute). */
struct nlmsghdr *nlmsghdr;
- uint8_t tail[TAIL_SIZE];
+ uint8_t tail[65536];
struct iovec iov[2];
- struct ofpbuf *buf;
struct msghdr msg;
ssize_t retval;
- *bufp = NULL;
+ assert(buf->allocated >= sizeof *nlmsghdr);
+ ofpbuf_clear(buf);
- buf = ofpbuf_new(HEAD_SIZE);
- iov[0].iov_base = buf->data;
- iov[0].iov_len = HEAD_SIZE;
+ iov[0].iov_base = buf->base;
+ iov[0].iov_len = buf->allocated;
iov[1].iov_base = tail;
- iov[1].iov_len = TAIL_SIZE;
+ iov[1].iov_len = sizeof tail;
memset(&msg, 0, sizeof msg);
msg.msg_iov = iov;
@@ -342,77 +336,65 @@ nl_sock_recv__(struct nl_sock *sock, struct ofpbuf **bufp, bool wait)
* the kernel tried to send to us. */
COVERAGE_INC(netlink_overflow);
}
- ofpbuf_delete(buf);
return error;
}
if (msg.msg_flags & MSG_TRUNC) {
- VLOG_ERR_RL(&rl, "truncated message (longer than %d bytes)", MAX_SIZE);
- ofpbuf_delete(buf);
+ VLOG_ERR_RL(&rl, "truncated message (longer than %d bytes)",
+ sizeof tail);
return E2BIG;
}
- ofpbuf_put_uninit(buf, MIN(retval, HEAD_SIZE));
- if (retval > HEAD_SIZE) {
- COVERAGE_INC(netlink_recv_jumbo);
- ofpbuf_put(buf, tail, retval - HEAD_SIZE);
- }
-
nlmsghdr = buf->data;
if (retval < sizeof *nlmsghdr
|| nlmsghdr->nlmsg_len < sizeof *nlmsghdr
|| nlmsghdr->nlmsg_len > retval) {
VLOG_ERR_RL(&rl, "received invalid nlmsg (%zd bytes < %d)",
- retval, NLMSG_HDRLEN);
- ofpbuf_delete(buf);
+ retval, sizeof *nlmsghdr);
return EPROTO;
}
if (STRESS(netlink_overflow)) {
- ofpbuf_delete(buf);
return ENOBUFS;
}
- *bufp = buf;
+ buf->size = MIN(retval, buf->allocated);
+ if (retval > buf->allocated) {
+ COVERAGE_INC(netlink_recv_jumbo);
+ ofpbuf_put(buf, tail, retval - buf->allocated);
+ }
+
log_nlmsg(__func__, 0, buf->data, buf->size, sock->protocol);
COVERAGE_INC(netlink_received);
return 0;
}
-/* Tries to receive a netlink message from the kernel on 'sock'. If
- * successful, stores the received message into '*bufp' and returns 0. The
- * caller is responsible for destroying the message with ofpbuf_delete(). On
- * failure, returns a positive errno value and stores a null pointer into
- * '*bufp'.
+/* Tries to receive a Netlink message from the kernel on 'sock' into 'buf'. If
+ * 'wait' is true, waits for a message to be ready. Otherwise, fails with
+ * EAGAIN if the 'sock' receive buffer is empty.
+ *
+ * The caller must have initialized 'buf' with an allocation of at least
+ * NLMSG_HDRLEN bytes. For best performance, the caller should allocate enough
+ * space for a "typical" message.
+ *
+ * On success, returns 0 and replaces 'buf''s previous content by the received
+ * message. This function expands 'buf''s allocated memory, as necessary, to
+ * hold the actual size of the received message.
*
- * If 'wait' is true, nl_sock_recv waits for a message to be ready; otherwise,
- * returns EAGAIN if the 'sock' receive buffer is empty. */
+ * On failure, returns a positive errno value and clears 'buf' to zero length.
+ * 'buf' retains its previous memory allocation.
+ *
+ * Regardless of success or failure, this function resets 'buf''s headroom to
+ * 0. */
int
-nl_sock_recv(struct nl_sock *sock, struct ofpbuf **bufp, bool wait)
+nl_sock_recv(struct nl_sock *sock, struct ofpbuf *buf, bool wait)
{
int error = nl_sock_cow__(sock);
if (error) {
return error;
}
- return nl_sock_recv__(sock, bufp, wait);
-}
-
-static int
-find_nl_transaction_by_seq(struct nl_transaction **transactions, size_t n,
- uint32_t seq)
-{
- int i;
-
- for (i = 0; i < n; i++) {
- struct nl_transaction *t = transactions[i];
-
- if (seq == nl_msg_nlmsghdr(t->request)->nlmsg_seq) {
- return i;
- }
- }
-
- return -1;
+ return nl_sock_recv__(sock, buf, wait);
}
static void
@@ -422,8 +404,12 @@ nl_sock_record_errors__(struct nl_transaction **transactions, size_t n,
size_t i;
for (i = 0; i < n; i++) {
- transactions[i]->error = error;
- transactions[i]->reply = NULL;
+ struct nl_transaction *txn = transactions[i];
+
+ txn->error = error;
+ if (txn->reply) {
+ ofpbuf_clear(txn->reply);
+ }
}
}
@@ -432,21 +418,28 @@ nl_sock_transact_multiple__(struct nl_sock *sock,
struct nl_transaction **transactions, size_t n,
size_t *done)
{
+ uint64_t tmp_reply_stub[1024 / 8];
+ struct nl_transaction tmp_txn;
+ struct ofpbuf tmp_reply;
+
+ uint32_t base_seq;
struct iovec iovs[MAX_IOVS];
struct msghdr msg;
int error;
int i;
+ base_seq = nl_sock_allocate_seq(sock, n);
*done = 0;
for (i = 0; i < n; i++) {
- struct ofpbuf *request = transactions[i]->request;
- struct nlmsghdr *nlmsg = nl_msg_nlmsghdr(request);
+ struct nl_transaction *txn = transactions[i];
+ struct nlmsghdr *nlmsg = nl_msg_nlmsghdr(txn->request);
- nlmsg->nlmsg_len = request->size;
+ nlmsg->nlmsg_len = txn->request->size;
+ nlmsg->nlmsg_seq = base_seq + i;
nlmsg->nlmsg_pid = sock->pid;
- iovs[i].iov_base = request->data;
- iovs[i].iov_len = request->size;
+ iovs[i].iov_base = txn->request->data;
+ iovs[i].iov_len = txn->request->size;
}
memset(&msg, 0, sizeof msg);
@@ -457,9 +450,9 @@ nl_sock_transact_multiple__(struct nl_sock *sock,
} while (error == EINTR);
for (i = 0; i < n; i++) {
- struct ofpbuf *request = transactions[i]->request;
+ struct nl_transaction *txn = transactions[i];
- log_nlmsg(__func__, error, request->data, request->size,
+ log_nlmsg(__func__, error, txn->request->data, txn->request->size,
sock->protocol);
}
if (!error) {
@@ -470,62 +463,93 @@ nl_sock_transact_multiple__(struct nl_sock *sock,
return error;
}
+ ofpbuf_use_stub(&tmp_reply, tmp_reply_stub, sizeof tmp_reply_stub);
+ tmp_txn.request = NULL;
+ tmp_txn.reply = &tmp_reply;
+ tmp_txn.error = 0;
while (n > 0) {
- struct ofpbuf *reply;
+ struct nl_transaction *buf_txn, *txn;
+ uint32_t seq;
+
+ /* Find a transaction whose buffer we can use for receiving a reply.
+ * If no such transaction is left, use tmp_txn. */
+ buf_txn = &tmp_txn;
+ for (i = 0; i < n; i++) {
+ if (transactions[i]->reply) {
+ buf_txn = transactions[i];
+ break;
+ }
+ }
- error = nl_sock_recv__(sock, &reply, false);
- if (error == EAGAIN) {
- nl_sock_record_errors__(transactions, n, 0);
- *done += n;
- return 0;
- } else if (error) {
- return error;
+ /* Receive a reply. */
+ error = nl_sock_recv__(sock, buf_txn->reply, false);
+ if (error) {
+ if (error == EAGAIN) {
+ nl_sock_record_errors__(transactions, n, 0);
+ *done += n;
+ error = 0;
+ }
+ break;
}
- i = find_nl_transaction_by_seq(transactions, n,
- nl_msg_nlmsghdr(reply)->nlmsg_seq);
- if (i < 0) {
- VLOG_DBG_RL(&rl, "ignoring unexpected seq %#"PRIx32,
- nl_msg_nlmsghdr(reply)->nlmsg_seq);
- ofpbuf_delete(reply);
+ /* Match the reply up with a transaction. */
+ seq = nl_msg_nlmsghdr(buf_txn->reply)->nlmsg_seq;
+ if (seq < base_seq || seq >= base_seq + n) {
+ VLOG_DBG_RL(&rl, "ignoring unexpected seq %#"PRIx32, seq);
continue;
}
+ i = seq - base_seq;
+ txn = transactions[i];
- nl_sock_record_errors__(transactions, i, 0);
- if (nl_msg_nlmsgerr(reply, &error)) {
- transactions[i]->reply = NULL;
- transactions[i]->error = error;
- if (error) {
+ /* Fill in the results for 'txn'. */
+ if (nl_msg_nlmsgerr(buf_txn->reply, &txn->error)) {
+ if (txn->reply) {
+ ofpbuf_clear(txn->reply);
+ }
+ if (txn->error) {
VLOG_DBG_RL(&rl, "received NAK error=%d (%s)",
- error, strerror(error));
+ error, strerror(txn->error));
}
- ofpbuf_delete(reply);
} else {
- transactions[i]->reply = reply;
- transactions[i]->error = 0;
+ txn->error = 0;
+ if (txn->reply && txn != buf_txn) {
+ /* Swap buffers. */
+ struct ofpbuf *reply = buf_txn->reply;
+ buf_txn->reply = txn->reply;
+ txn->reply = reply;
+ }
}
+ /* Fill in the results for transactions before 'txn'. (We have to do
+ * this after the results for 'txn' itself because of the buffer swap
+ * above.) */
+ nl_sock_record_errors__(transactions, i, 0);
+
+ /* Advance. */
*done += i + 1;
transactions += i + 1;
n -= i + 1;
+ base_seq += i + 1;
}
+ ofpbuf_uninit(&tmp_reply);
- return 0;
+ return error;
}
-/* Sends the 'request' member of the 'n' transactions in 'transactions' to the
- * kernel, in order, and waits for responses to all of them. Fills in the
+/* Sends the 'request' member of the 'n' transactions in 'transactions' on
+ * 'sock', in order, and receives responses to all of them. Fills in the
* 'error' member of each transaction with 0 if it was successful, otherwise
- * with a positive errno value. 'reply' will be NULL on error or if the
- * transaction was successful but had no reply beyond an indication of success.
- * For a successful transaction that did have a more detailed reply, 'reply'
- * will be set to the reply message.
+ * with a positive errno value. If 'reply' is nonnull, then it will be filled
+ * with the reply if the message receives a detailed reply. In other cases,
+ * i.e. where the request failed or had no reply beyond an indication of
+ * success, 'reply' will be cleared if it is nonnull.
*
* The caller is responsible for destroying each request and reply, and the
* transactions array itself.
*
* Before sending each message, this function will finalize nlmsg_len in each
- * 'request' to match the ofpbuf's size, and set nlmsg_pid to 'sock''s pid.
+ * 'request' to match the ofpbuf's size, set nlmsg_pid to 'sock''s pid, and
+ * initialize nlmsg_seq.
*
* Bare Netlink is an unreliable transport protocol. This function layers
* reliable delivery and reply semantics on top of bare Netlink. See
@@ -640,13 +664,20 @@ nl_sock_transact(struct nl_sock *sock, const struct ofpbuf *request,
struct nl_transaction transaction;
transaction.request = (struct ofpbuf *) request;
+ transaction.reply = replyp ? ofpbuf_new(1024) : NULL;
transactionp = &transaction;
+
nl_sock_transact_multiple(sock, &transactionp, 1);
+
if (replyp) {
- *replyp = transaction.reply;
- } else {
- ofpbuf_delete(transaction.reply);
+ if (transaction.error) {
+ ofpbuf_delete(transaction.reply);
+ *replyp = NULL;
+ } else {
+ *replyp = transaction.reply;
+ }
}
+
return transaction.error;
}
@@ -724,7 +755,7 @@ void
nl_dump_start(struct nl_dump *dump,
struct nl_sock *sock, const struct ofpbuf *request)
{
- dump->buffer = NULL;
+ ofpbuf_init(&dump->buffer, 4096);
if (sock->dump) {
/* 'sock' already has an ongoing dump. Clone the socket because
* Netlink only allows one dump at a time. */
@@ -745,26 +776,24 @@ nl_dump_start(struct nl_dump *dump,
/* Helper function for nl_dump_next(). */
static int
-nl_dump_recv(struct nl_dump *dump, struct ofpbuf **bufferp)
+nl_dump_recv(struct nl_dump *dump)
{
struct nlmsghdr *nlmsghdr;
- struct ofpbuf *buffer;
int retval;
- retval = nl_sock_recv__(dump->sock, bufferp, true);
+ retval = nl_sock_recv__(dump->sock, &dump->buffer, true);
if (retval) {
return retval == EINTR ? EAGAIN : retval;
}
- buffer = *bufferp;
- nlmsghdr = nl_msg_nlmsghdr(buffer);
+ nlmsghdr = nl_msg_nlmsghdr(&dump->buffer);
if (dump->seq != nlmsghdr->nlmsg_seq) {
VLOG_DBG_RL(&rl, "ignoring seq %#"PRIx32" != expected %#"PRIx32,
nlmsghdr->nlmsg_seq, dump->seq);
return EAGAIN;
}
- if (nl_msg_nlmsgerr(buffer, &retval)) {
+ if (nl_msg_nlmsgerr(&dump->buffer, &retval)) {
VLOG_INFO_RL(&rl, "netlink dump request error (%s)",
strerror(retval));
return retval && retval != EAGAIN ? retval : EPROTO;
@@ -796,15 +825,10 @@ nl_dump_next(struct nl_dump *dump, struct ofpbuf *reply)
return false;
}
- if (dump->buffer && !dump->buffer->size) {
- ofpbuf_delete(dump->buffer);
- dump->buffer = NULL;
- }
- while (!dump->buffer) {
- int retval = nl_dump_recv(dump, &dump->buffer);
+ while (!dump->buffer.size) {
+ int retval = nl_dump_recv(dump);
if (retval) {
- ofpbuf_delete(dump->buffer);
- dump->buffer = NULL;
+ ofpbuf_clear(&dump->buffer);
if (retval != EAGAIN) {
dump->status = retval;
return false;
@@ -812,7 +836,7 @@ nl_dump_next(struct nl_dump *dump, struct ofpbuf *reply)
}
}
- nlmsghdr = nl_msg_next(dump->buffer, reply);
+ nlmsghdr = nl_msg_next(&dump->buffer, reply);
if (!nlmsghdr) {
VLOG_WARN_RL(&rl, "netlink dump reply contains message fragment");
dump->status = EPROTO;
@@ -847,7 +871,7 @@ nl_dump_done(struct nl_dump *dump)
nl_sock_destroy(dump->sock);
}
}
- ofpbuf_delete(dump->buffer);
+ ofpbuf_uninit(&dump->buffer);
return dump->status == EOF ? 0 : dump->status;
}
@@ -1187,5 +1211,3 @@ log_nlmsg(const char *function, int error,
VLOG_DBG_RL(&rl, "%s (%s): %s", function, strerror(error), nlmsg);
free(nlmsg);
}
-
-
diff --git a/lib/netlink-socket.h b/lib/netlink-socket.h
index 9d288bd..0232616 100644
--- a/lib/netlink-socket.h
+++ b/lib/netlink-socket.h
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -35,8 +35,8 @@
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
+#include "ofpbuf.h"
-struct ofpbuf;
struct nl_sock;
#ifndef HAVE_NETLINK
@@ -52,9 +52,9 @@ int nl_sock_join_mcgroup(struct nl_sock *, unsigned int multicast_group);
int nl_sock_leave_mcgroup(struct nl_sock *, unsigned int multicast_group);
int nl_sock_send(struct nl_sock *, const struct ofpbuf *, bool wait);
-int nl_sock_recv(struct nl_sock *, struct ofpbuf **, bool wait);
+int nl_sock_recv(struct nl_sock *, struct ofpbuf *, bool wait);
int nl_sock_transact(struct nl_sock *, const struct ofpbuf *request,
- struct ofpbuf **reply);
+ struct ofpbuf **replyp);
int nl_sock_drain(struct nl_sock *);
@@ -68,8 +68,14 @@ struct nl_transaction {
/* Filled in by client. */
struct ofpbuf *request; /* Request to send. */
- /* Filled in by nl_sock_transact_batch(). */
- struct ofpbuf *reply; /* Reply (NULL if reply was an error code). */
+ /* The client must initialize 'reply' to one of:
+ *
+ * - NULL, if it does not care to examine the reply.
+ *
+ * - Otherwise, to an ofpbuf with a memory allocation of at least
+ * NLMSG_HDRLEN bytes.
+ */
+ struct ofpbuf *reply; /* Reply (empty if reply was an error code). */
int error; /* Positive errno value, 0 if no error. */
};
@@ -80,7 +86,7 @@ void nl_sock_transact_multiple(struct nl_sock *,
struct nl_dump {
struct nl_sock *sock; /* Socket being dumped. */
uint32_t seq; /* Expected nlmsg_seq for replies. */
- struct ofpbuf *buffer; /* Receive buffer currently being iterated. */
+ struct ofpbuf buffer; /* Receive buffer currently being iterated. */
int status; /* 0=OK, EOF=done, or positive errno value. */
};
diff --git a/utilities/nlmon.c b/utilities/nlmon.c
index 1b2f1e2..e6cf023 100644
--- a/utilities/nlmon.c
+++ b/utilities/nlmon.c
@@ -39,7 +39,9 @@ static const struct nl_policy rtnlgrp_link_policy[] = {
int
main(int argc OVS_UNUSED, char *argv[])
{
+ uint64_t buf_stub[4096 / 64];
struct nl_sock *sock;
+ struct ofpbuf buf;
int error;
set_program_name(argv[0]);
@@ -55,9 +57,8 @@ main(int argc OVS_UNUSED, char *argv[])
ovs_fatal(error, "could not join RTNLGRP_LINK multicast group");
}
+ ofpbuf_use_stub(&buf, buf_stub, sizeof buf_stub);
for (;;) {
- struct ofpbuf *buf;
-
error = nl_sock_recv(sock, &buf, false);
if (error == EAGAIN) {
/* Nothing to do. */
@@ -95,19 +96,17 @@ main(int argc OVS_UNUSED, char *argv[])
struct ifinfomsg *iim;
int i;
- nlh = ofpbuf_at(buf, 0, NLMSG_HDRLEN);
- iim = ofpbuf_at(buf, NLMSG_HDRLEN, sizeof *iim);
+ nlh = ofpbuf_at(&buf, 0, NLMSG_HDRLEN);
+ iim = ofpbuf_at(&buf, NLMSG_HDRLEN, sizeof *iim);
if (!iim) {
ovs_error(0, "received bad rtnl message (no ifinfomsg)");
- ofpbuf_delete(buf);
continue;
}
- if (!nl_policy_parse(buf, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
+ if (!nl_policy_parse(&buf, NLMSG_HDRLEN + sizeof(struct ifinfomsg),
rtnlgrp_link_policy,
attrs, ARRAY_SIZE(rtnlgrp_link_policy))) {
ovs_error(0, "received bad rtnl message (policy)");
- ofpbuf_delete(buf);
continue;
}
printf("netdev %s changed (%s):\n",
@@ -132,7 +131,6 @@ main(int argc OVS_UNUSED, char *argv[])
}
printf("\tmaster=%"PRIu32" (%s)\n", idx, ifname);
}
- ofpbuf_delete(buf);
}
nl_sock_wait(sock, POLLIN);
diff --git a/vswitchd/ovs-brcompatd.c b/vswitchd/ovs-brcompatd.c
index 18a6708..8b1ad5d 100644
--- a/vswitchd/ovs-brcompatd.c
+++ b/vswitchd/ovs-brcompatd.c
@@ -1,4 +1,4 @@
-/* Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks
+/* Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira Networks
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -654,56 +654,53 @@ handle_get_ports_cmd(struct ofpbuf *buffer)
return 0;
}
-static struct ofpbuf *
-brc_recv_update__(void)
+static bool
+brc_recv_update__(struct ofpbuf *buffer)
{
for (;;) {
- struct ofpbuf *buffer;
- int retval;
-
- retval = nl_sock_recv(brc_sock, &buffer, false);
+ int retval = nl_sock_recv(brc_sock, buffer, false);
switch (retval) {
case 0:
if (nl_msg_nlmsgerr(buffer, NULL)
|| nl_msg_nlmsghdr(buffer)->nlmsg_type == NLMSG_DONE) {
break;
}
- return buffer;
+ return true;
case ENOBUFS:
break;
case EAGAIN:
- return NULL;
+ return false;
default:
VLOG_WARN_RL(&rl, "brc_recv_update: %s", strerror(retval));
- return NULL;
+ return false;
}
- ofpbuf_delete(buffer);
}
}
static void
brc_recv_update(void)
{
- struct ofpbuf *buffer;
struct genlmsghdr *genlmsghdr;
+ uint64_t buffer_stub[1024 / 8];
+ struct ofpbuf buffer;
- buffer = brc_recv_update__();
- if (!buffer) {
- return;
+ ofpbuf_use_stub(&buffer, buffer_stub, sizeof buffer_stub);
+ if (!brc_recv_update__(&buffer)) {
+ goto error;
}
- genlmsghdr = nl_msg_genlmsghdr(buffer);
+ genlmsghdr = nl_msg_genlmsghdr(&buffer);
if (!genlmsghdr) {
VLOG_WARN_RL(&rl, "received packet too short for generic NetLink");
goto error;
}
- if (nl_msg_nlmsghdr(buffer)->nlmsg_type != brc_family) {
+ if (nl_msg_nlmsghdr(&buffer)->nlmsg_type != brc_family) {
VLOG_DBG_RL(&rl, "received type (%"PRIu16") != brcompat family (%d)",
- nl_msg_nlmsghdr(buffer)->nlmsg_type, brc_family);
+ nl_msg_nlmsghdr(&buffer)->nlmsg_type, brc_family);
goto error;
}
@@ -729,31 +726,31 @@ brc_recv_update(void)
switch (genlmsghdr->cmd) {
case BRC_GENL_C_DP_ADD:
- handle_bridge_cmd(buffer, true);
+ handle_bridge_cmd(&buffer, true);
break;
case BRC_GENL_C_DP_DEL:
- handle_bridge_cmd(buffer, false);
+ handle_bridge_cmd(&buffer, false);
break;
case BRC_GENL_C_PORT_ADD:
- handle_port_cmd(buffer, true);
+ handle_port_cmd(&buffer, true);
break;
case BRC_GENL_C_PORT_DEL:
- handle_port_cmd(buffer, false);
+ handle_port_cmd(&buffer, false);
break;
case BRC_GENL_C_FDB_QUERY:
- handle_fdb_query_cmd(buffer);
+ handle_fdb_query_cmd(&buffer);
break;
case BRC_GENL_C_GET_BRIDGES:
- handle_get_bridges_cmd(buffer);
+ handle_get_bridges_cmd(&buffer);
break;
case BRC_GENL_C_GET_PORTS:
- handle_get_ports_cmd(buffer);
+ handle_get_ports_cmd(&buffer);
break;
default:
@@ -763,7 +760,7 @@ brc_recv_update(void)
}
error:
- ofpbuf_delete(buffer);
+ ofpbuf_uninit(&buffer);
}
static void
--
1.7.9
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