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>

1 files changed, 44 insertions, 53 deletions

diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index db94a2513dd8..68b7baea3fea 100644
--- 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,
         };