sctp: remove prsctp_param from sctp_chunk

Now sctp uses chunk->prsctp_param to save the prsctp param for all the
prsctp polices, we didn't need to introduce prsctp_param to sctp_chunk.
We can just use chunk->sinfo.sinfo_timetolive for RTX and BUF polices,
and reuse msg->expires_at for TTL policy, as the prsctp polices and old
expires policy are mutual exclusive.

This patch is to remove prsctp_param from sctp_chunk, and reuse msg's
expires_at for TTL and chunk's sinfo.sinfo_timetolive for RTX and BUF
polices.

Note that sctp can't use chunk's sinfo.sinfo_timetolive for TTL policy,
as it needs a u64 variables to save the expires_at time.

This one also fixes the "netperf-Throughput_Mbps -37.2% regression"
issue.

Fixes: a6c2f792873a ("sctp: implement prsctp TTL policy")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 9 insertions, 26 deletions

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 4f097f538fff..ced0df374e60 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -606,13 +606,6 @@ struct sctp_chunk {
         /* This needs to be recoverable for SCTP_SEND_FAILED events. */
         struct sctp_sndrcvinfo sinfo;
 
-        /* We use this field to record param for prsctp policies,
-         * for TTL policy, it is the time_to_drop of this chunk,
-         * for RTX policy, it is the max_sent_count of this chunk,
-         * for PRIO policy, it is the priority of this chunk.
-         */
-        unsigned long prsctp_param;
-
         /* Which association does this belong to?  */
         struct sctp_association *asoc;
 
diff --git a/net/sctp/chunk.c b/net/sctp/chunk.c
index a55e54738b81..14990e21cf55 100644
--- a/net/sctp/chunk.c
+++ b/net/sctp/chunk.c
@@ -179,6 +179,11 @@ struct sctp_datamsg *sctp_datamsg_from_user(struct sctp_association *asoc,
                          msg, msg->expires_at, jiffies);
         }
 
+        if (asoc->prsctp_enable &&
+            SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
+                msg->expires_at =
+                        jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
+
         /* This is the biggest possible DATA chunk that can fit into
          * the packet
          */
@@ -349,14 +354,14 @@ int sctp_chunk_abandoned(struct sctp_chunk *chunk)
         }
 
         if (SCTP_PR_TTL_ENABLED(chunk->sinfo.sinfo_flags) &&
-            time_after(jiffies, chunk->prsctp_param)) {
+            time_after(jiffies, chunk->msg->expires_at)) {
                 if (chunk->sent_count)
                         chunk->asoc->abandoned_sent[SCTP_PR_INDEX(TTL)]++;
                 else
                         chunk->asoc->abandoned_unsent[SCTP_PR_INDEX(TTL)]++;
                 return 1;
         } else if (SCTP_PR_RTX_ENABLED(chunk->sinfo.sinfo_flags) &&
-                   chunk->sent_count > chunk->prsctp_param) {
+                   chunk->sent_count > chunk->sinfo.sinfo_timetolive) {
                 chunk->asoc->abandoned_sent[SCTP_PR_INDEX(RTX)]++;
                 return 1;
         }
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 72e54a416af6..e084f35d40d2 100644
--- a/net/sctp/outqueue.c
+++ b/net/sctp/outqueue.c
@@ -383,7 +383,7 @@ static int sctp_prsctp_prune_sent(struct sctp_association *asoc,
 
         list_for_each_entry_safe(chk, temp, queue, transmitted_list) {
                 if (!SCTP_PR_PRIO_ENABLED(chk->sinfo.sinfo_flags) ||
-                    chk->prsctp_param <= sinfo->sinfo_timetolive)
+                    chk->sinfo.sinfo_timetolive <= sinfo->sinfo_timetolive)
                         continue;
 
                 list_del_init(&chk->transmitted_list);
@@ -418,7 +418,7 @@ static int sctp_prsctp_prune_unsent(struct sctp_association *asoc,
 
         list_for_each_entry_safe(chk, temp, queue, list) {
                 if (!SCTP_PR_PRIO_ENABLED(chk->sinfo.sinfo_flags) ||
-                    chk->prsctp_param <= sinfo->sinfo_timetolive)
+                    chk->sinfo.sinfo_timetolive <= sinfo->sinfo_timetolive)
                         continue;
 
                 list_del_init(&chk->list);
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 8c77b87a8565..46ffecc57214 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -706,20 +706,6 @@ nodata:
         return retval;
 }
 
-static void sctp_set_prsctp_policy(struct sctp_chunk *chunk,
-                                   const struct sctp_sndrcvinfo *sinfo)
-{
-        if (!chunk->asoc->prsctp_enable)
-                return;
-
-        if (SCTP_PR_TTL_ENABLED(sinfo->sinfo_flags))
-                chunk->prsctp_param =
-                        jiffies + msecs_to_jiffies(sinfo->sinfo_timetolive);
-        else if (SCTP_PR_RTX_ENABLED(sinfo->sinfo_flags) ||
-                 SCTP_PR_PRIO_ENABLED(sinfo->sinfo_flags))
-                chunk->prsctp_param = sinfo->sinfo_timetolive;
-}
-
 /* Make a DATA chunk for the given association from the provided
  * parameters.  However, do not populate the data payload.
  */
@@ -753,7 +739,6 @@ struct sctp_chunk *sctp_make_datafrag_empty(struct sctp_association *asoc,
 
         retval->subh.data_hdr = sctp_addto_chunk(retval, sizeof(dp), &dp);
         memcpy(&retval->sinfo, sinfo, sizeof(struct sctp_sndrcvinfo));
-        sctp_set_prsctp_policy(retval, sinfo);
 
 nodata:
         return retval;