mirror of
https://github.com/FEX-Emu/linux.git
synced 2025-02-25 15:13:35 +00:00
286ab3d460
"struct proto" currently uses an array stats[NR_CPUS] to track change on 'inuse' sockets per protocol. If NR_CPUS is big, this means we use a big memory area for this. Moreover, all this memory area is located on a single node on NUMA machines, increasing memory pressure on the boot node. In this patch, I tried to : - Keep a fast !CONFIG_SMP implementation - Keep a fast CONFIG_SMP implementation for often used protocols (tcp,udp,raw,...) - Introduce a NUMA efficient implementation Some helper macros are defined in include/net/sock.h These macros take into account CONFIG_SMP If a "struct proto" is declared without using DEFINE_PROTO_INUSE / REF_PROTO_INUSE macros, it will automatically use a default implementation, using a dynamically allocated percpu zone. This default implementation will be NUMA efficient, but might use 32/64 bytes per possible cpu because of current alloc_percpu() implementation. However it still should be better than previous implementation based on stats[NR_CPUS] field. When a "struct proto" is changed to use the new macros, we use a single static "int" percpu variable, lowering the memory and cpu costs, still preserving NUMA efficiency. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>