lkml.org 
[lkml]   [2020]   [May]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/2] sctp: implement memory accounting on tx path
Date
From: Xin Long <lucien.xin@gmail.com>

commit 1033990ac5b2ab6cee93734cb6d301aa3a35bcaa upstream.

Now when sending packets, sk_mem_charge() and sk_mem_uncharge() have been
used to set sk_forward_alloc. We just need to call sk_wmem_schedule() to
check if the allocated should be raised, and call sk_mem_reclaim() to
check if the allocated should be reduced when it's under memory pressure.

If sk_wmem_schedule() returns false, which means no memory is allowed to
allocate, it will block and wait for memory to become available.

Note different from tcp, sctp wait_for_buf happens before allocating any
skb, so memory accounting check is done with the whole msg_len before it
too.

Reported-by: Matteo Croce <mcroce@redhat.com>
Tested-by: Matteo Croce <mcroce@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ashwin H <ashwinh@vmware.com>
---
net/sctp/socket.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index c93be3b..df4a7d7 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -1931,7 +1931,10 @@ static int sctp_sendmsg_to_asoc(struct sctp_association *asoc,
if (sctp_wspace(asoc) < (int)msg_len)
sctp_prsctp_prune(asoc, sinfo, msg_len - sctp_wspace(asoc));

- if (sctp_wspace(asoc) <= 0) {
+ if (sk_under_memory_pressure(sk))
+ sk_mem_reclaim(sk);
+
+ if (sctp_wspace(asoc) <= 0 || !sk_wmem_schedule(sk, msg_len)) {
timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
err = sctp_wait_for_sndbuf(asoc, &timeo, msg_len);
if (err)
@@ -8515,7 +8518,10 @@ static int sctp_wait_for_sndbuf(struct sctp_association *asoc, long *timeo_p,
goto do_error;
if (signal_pending(current))
goto do_interrupted;
- if ((int)msg_len <= sctp_wspace(asoc))
+ if (sk_under_memory_pressure(sk))
+ sk_mem_reclaim(sk);
+ if ((int)msg_len <= sctp_wspace(asoc) &&
+ sk_wmem_schedule(sk, msg_len))
break;

/* Let another process have a go. Since we are going
--
2.7.4
\
 
 \ /
  Last update: 2020-05-06 08:33    [W:0.247 / U:0.004 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site