sctp: add asoc and packet to sctp_flush_ctx

Pre-compute these so the compiler won't reload them (due to
no-strict-aliasing).

Changes since v2:
- Do not replace a return with a break in sctp_outq_flush_data

Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index db94a25..68b7bae 100644 (file)
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -798,16 +798,17 @@ struct sctp_flush_ctx {
        struct sctp_transport *transport;
        /* These transports have chunks to send. */
        struct list_head transport_list;
+       struct sctp_association *asoc;
+       /* Packet on the current transport above */
+       struct sctp_packet *packet;
        gfp_t gfp;
 };
 
 /* transport: current transport */
-static bool sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
+static void sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
                                       struct sctp_chunk *chunk)
 {
        struct sctp_transport *new_transport = chunk->transport;
-       struct sctp_association *asoc = ctx->q->asoc;
-       bool changed = false;
 
        if (!new_transport) {
                if (!sctp_chunk_is_data(chunk)) {
@@ -825,7 +826,7 @@ static bool sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
                                                        &ctx->transport->ipaddr))
                                new_transport = ctx->transport;
                        else
-                               new_transport = sctp_assoc_lookup_paddr(asoc,
+                               new_transport = sctp_assoc_lookup_paddr(ctx->asoc,
                                                                  &chunk->dest);
                }
 
@@ -833,7 +834,7 @@ static bool sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
                 * use the current active path.
                 */
                if (!new_transport)
-                       new_transport = asoc->peer.active_path;
+                       new_transport = ctx->asoc->peer.active_path;
        } else {
                __u8 type;
 
@@ -858,7 +859,7 @@ static bool sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
                        if (type != SCTP_CID_HEARTBEAT &&
                            type != SCTP_CID_HEARTBEAT_ACK &&
                            type != SCTP_CID_ASCONF_ACK)
-                               new_transport = asoc->peer.active_path;
+                               new_transport = ctx->asoc->peer.active_path;
                        break;
                default:
                        break;
@@ -867,27 +868,25 @@ static bool sctp_outq_select_transport(struct sctp_flush_ctx *ctx,
 
        /* Are we switching transports? Take care of transport locks. */
        if (new_transport != ctx->transport) {
-               changed = true;
                ctx->transport = new_transport;
+               ctx->packet = &ctx->transport->packet;
+
                if (list_empty(&ctx->transport->send_ready))
                        list_add_tail(&ctx->transport->send_ready,
                                      &ctx->transport_list);
 
-               sctp_packet_config(&ctx->transport->packet, asoc->peer.i.init_tag,
-                                  asoc->peer.ecn_capable);
+               sctp_packet_config(ctx->packet,
+                                  ctx->asoc->peer.i.init_tag,
+                                  ctx->asoc->peer.ecn_capable);
                /* We've switched transports, so apply the
                 * Burst limit to the new transport.
                 */
                sctp_transport_burst_limited(ctx->transport);
        }
-
-       return changed;
 }
 
 static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
 {
-       struct sctp_association *asoc = ctx->q->asoc;
-       struct sctp_packet *packet = NULL;
        struct sctp_chunk *chunk, *tmp;
        enum sctp_xmit status;
        int one_packet, error;
@@ -901,7 +900,7 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                 * NOT use the new IP address as a source for ANY SCTP
                 * packet except on carrying an ASCONF Chunk.
                 */
-               if (asoc->src_out_of_asoc_ok &&
+               if (ctx->asoc->src_out_of_asoc_ok &&
                    chunk->chunk_hdr->type != SCTP_CID_ASCONF)
                        continue;
 
@@ -910,8 +909,7 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                /* Pick the right transport to use. Should always be true for
                 * the first chunk as we don't have a transport by then.
                 */
-               if (sctp_outq_select_transport(ctx, chunk))
-                       packet = &ctx->transport->packet;
+               sctp_outq_select_transport(ctx, chunk);
 
                switch (chunk->chunk_hdr->type) {
                /*
@@ -926,14 +924,14 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                        error = sctp_packet_singleton(ctx->transport, chunk,
                                                      ctx->gfp);
                        if (error < 0) {
-                               asoc->base.sk->sk_err = -error;
+                               ctx->asoc->base.sk->sk_err = -error;
                                return;
                        }
                        break;
 
                case SCTP_CID_ABORT:
                        if (sctp_test_T_bit(chunk))
-                               packet->vtag = asoc->c.my_vtag;
+                               ctx->packet->vtag = ctx->asoc->c.my_vtag;
                        /* fallthru */
 
                /* The following chunks are "response" chunks, i.e.
@@ -959,7 +957,7 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                case SCTP_CID_FWD_TSN:
                case SCTP_CID_I_FWD_TSN:
                case SCTP_CID_RECONF:
-                       status = sctp_packet_transmit_chunk(packet, chunk,
+                       status = sctp_packet_transmit_chunk(ctx->packet, chunk,
                                                            one_packet, ctx->gfp);
                        if (status != SCTP_XMIT_OK) {
                                /* put the chunk back */
@@ -967,7 +965,7 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                                break;
                        }
 
-                       asoc->stats.octrlchunks++;
+                       ctx->asoc->stats.octrlchunks++;
                        /* PR-SCTP C5) If a FORWARD TSN is sent, the
                         * sender MUST assure that at least one T3-rtx
                         * timer is running.
@@ -978,7 +976,7 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
                                ctx->transport->last_time_sent = jiffies;
                        }
 
-                       if (chunk == asoc->strreset_chunk)
+                       if (chunk == ctx->asoc->strreset_chunk)
                                sctp_transport_reset_reconf_timer(ctx->transport);
 
                        break;
@@ -994,31 +992,28 @@ static void sctp_outq_flush_ctrl(struct sctp_flush_ctx *ctx)
 static bool sctp_outq_flush_rtx(struct sctp_flush_ctx *ctx,
                                int rtx_timeout)
 {
-       struct sctp_packet *packet = ctx->transport ? &ctx->transport->packet :
-                                    NULL;
-       struct sctp_association *asoc = ctx->q->asoc;
        int error, start_timer = 0;
 
-       if (asoc->peer.retran_path->state == SCTP_UNCONFIRMED)
+       if (ctx->asoc->peer.retran_path->state == SCTP_UNCONFIRMED)
                return false;
 
-       if (ctx->transport != asoc->peer.retran_path) {
+       if (ctx->transport != ctx->asoc->peer.retran_path) {
                /* Switch transports & prepare the packet.  */
-               ctx->transport = asoc->peer.retran_path;
+               ctx->transport = ctx->asoc->peer.retran_path;
+               ctx->packet = &ctx->transport->packet;
 
                if (list_empty(&ctx->transport->send_ready))
                        list_add_tail(&ctx->transport->send_ready,
                                      &ctx->transport_list);
 
-               packet = &ctx->transport->packet;
-               sctp_packet_config(packet, asoc->peer.i.init_tag,
-                                  asoc->peer.ecn_capable);
+               sctp_packet_config(ctx->packet, ctx->asoc->peer.i.init_tag,
+                                  ctx->asoc->peer.ecn_capable);
        }
 
-       error = __sctp_outq_flush_rtx(ctx->q, packet, rtx_timeout, &start_timer,
-                                     ctx->gfp);
+       error = __sctp_outq_flush_rtx(ctx->q, ctx->packet, rtx_timeout,
+                                     &start_timer, ctx->gfp);
        if (error < 0)
-               asoc->base.sk->sk_err = -error;
+               ctx->asoc->base.sk->sk_err = -error;
 
        if (start_timer) {
                sctp_transport_reset_t3_rtx(ctx->transport);
@@ -1028,7 +1023,7 @@ static bool sctp_outq_flush_rtx(struct sctp_flush_ctx *ctx,
        /* This can happen on COOKIE-ECHO resend.  Only
         * one chunk can get bundled with a COOKIE-ECHO.
         */
-       if (packet->has_cookie_echo)
+       if (ctx->packet->has_cookie_echo)
                return false;
 
        /* Don't send new data if there is still data
@@ -1043,19 +1038,16 @@ static bool sctp_outq_flush_rtx(struct sctp_flush_ctx *ctx,
 static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
                                 int rtx_timeout)
 {
-       struct sctp_packet *packet = ctx->transport ? &ctx->transport->packet :
-                                    NULL;
-       struct sctp_association *asoc = ctx->q->asoc;
        struct sctp_chunk *chunk;
        enum sctp_xmit status;
 
        /* Is it OK to send data chunks?  */
-       switch (asoc->state) {
+       switch (ctx->asoc->state) {
        case SCTP_STATE_COOKIE_ECHOED:
                /* Only allow bundling when this packet has a COOKIE-ECHO
                 * chunk.
                 */
-               if (!packet || !packet->has_cookie_echo)
+               if (!ctx->packet || !ctx->packet->has_cookie_echo)
                        return;
 
                /* fallthru */
@@ -1078,12 +1070,9 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
         * are marked for retransmission (limited by the
         * current cwnd).
         */
-       if (!list_empty(&ctx->q->retransmit)) {
-               if (!sctp_outq_flush_rtx(ctx, rtx_timeout))
-                       return;
-               /* We may have switched current transport */
-               packet = &ctx->transport->packet;
-       }
+       if (!list_empty(&ctx->q->retransmit) &&
+           !sctp_outq_flush_rtx(ctx, rtx_timeout))
+               return;
 
        /* Apply Max.Burst limitation to the current transport in
         * case it will be used for new data.  We are going to
@@ -1105,13 +1094,12 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
                        continue;
                }
 
-               if (asoc->stream.out[sid].state == SCTP_STREAM_CLOSED) {
+               if (ctx->asoc->stream.out[sid].state == SCTP_STREAM_CLOSED) {
                        sctp_outq_head_data(ctx->q, chunk);
                        break;
                }
 
-               if (sctp_outq_select_transport(ctx, chunk))
-                       packet = &ctx->transport->packet;
+               sctp_outq_select_transport(ctx, chunk);
 
                pr_debug("%s: outq:%p, chunk:%p[%s], tx-tsn:0x%x skb->head:%p "
                         "skb->users:%d\n",
@@ -1122,7 +1110,8 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
                         refcount_read(&chunk->skb->users) : -1);
 
                /* Add the chunk to the packet.  */
-               status = sctp_packet_transmit_chunk(packet, chunk, 0, ctx->gfp);
+               status = sctp_packet_transmit_chunk(ctx->packet, chunk, 0,
+                                                   ctx->gfp);
                if (status != SCTP_XMIT_OK) {
                        /* We could not append this chunk, so put
                         * the chunk back on the output queue.
@@ -1139,12 +1128,12 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
                 * The sender MAY set the I-bit in the DATA
                 * chunk header.
                 */
-               if (asoc->state == SCTP_STATE_SHUTDOWN_PENDING)
+               if (ctx->asoc->state == SCTP_STATE_SHUTDOWN_PENDING)
                        chunk->chunk_hdr->flags |= SCTP_DATA_SACK_IMM;
                if (chunk->chunk_hdr->flags & SCTP_DATA_UNORDERED)
-                       asoc->stats.ouodchunks++;
+                       ctx->asoc->stats.ouodchunks++;
                else
-                       asoc->stats.oodchunks++;
+                       ctx->asoc->stats.oodchunks++;
 
                /* Only now it's safe to consider this
                 * chunk as sent, sched-wise.
@@ -1160,7 +1149,7 @@ static void sctp_outq_flush_data(struct sctp_flush_ctx *ctx,
                /* Only let one DATA chunk get bundled with a
                 * COOKIE-ECHO chunk.
                 */
-               if (packet->has_cookie_echo)
+               if (ctx->packet->has_cookie_echo)
                        break;
        }
 }
@@ -1202,6 +1191,8 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
                .q = q,
                .transport = NULL,
                .transport_list = LIST_HEAD_INIT(ctx.transport_list),
+               .asoc = q->asoc,
+               .packet = NULL,
                .gfp = gfp,
        };