xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

mptcp: try harder to borrow memory from subflow under pressure

Browse Source 
[ Upstream commit 72f961320d5d15bfcb26dbe3edaa3f7d25fd2c8a ]

If the host is under sever memory pressure, and RX forward
memory allocation for the msk fails, we try to borrow the
required memory from the ingress subflow.

The current attempt is a bit flaky: if skb->truesize is less
than SK_MEM_QUANTUM, the ssk will not release any memory, and
the next schedule will fail again.

Instead, directly move the required amount of pages from the
ssk to the msk, if available

Fixes: 9c3f94e168 ("mptcp: add missing memory scheduling in the rx path")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Paolo Abeni
2021-06-10 15:59:40 -07:00
committed by Greg Kroah-Hartman
parent 3b491dd593
commit 222ebeda17
1 changed files with 6 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
net/mptcp/protocol.c
View File

@@ -276,11 +276,13 @@ static bool __mptcp_move_skb(struct mptcp_sock *msk, struct sock *ssk,
/* try to fetch required memory from subflow */ /* try to fetch required memory from subflow */
if (!sk_rmem_schedule(sk, skb, skb->truesize)) { if (!sk_rmem_schedule(sk, skb, skb->truesize)) {
if (ssk->sk_forward_alloc < skb->truesize) int amount = sk_mem_pages(skb->truesize) << SK_MEM_QUANTUM_SHIFT;
goto drop;
__sk_mem_reclaim(ssk, skb->truesize); if (ssk->sk_forward_alloc < amount)
if (!sk_rmem_schedule(sk, skb, skb->truesize))
goto drop; goto drop;
ssk->sk_forward_alloc -= amount;
sk->sk_forward_alloc += amount;
} }
/* the skb map_seq accounts for the skb offset: /* the skb map_seq accounts for the skb offset: