diff options
author | Ilya Maximets <i.maximets@ovn.org> | 2023-09-21 21:42:35 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2023-10-01 19:07:22 +0100 |
commit | 06bc3668cc2a6db2831b9086f0e3c6ebda599dba (patch) | |
tree | 4726d59871f1ebdd05dc84f1508bd45c4b0508b0 /net/xdp/xsk.c | |
parent | c1157c114a23029a93dc8b5a766a1acea8db2686 (diff) | |
download | linux-stable-06bc3668cc2a6db2831b9086f0e3c6ebda599dba.tar.gz linux-stable-06bc3668cc2a6db2831b9086f0e3c6ebda599dba.tar.bz2 linux-stable-06bc3668cc2a6db2831b9086f0e3c6ebda599dba.zip |
openvswitch: reduce stack usage in do_execute_actions
do_execute_actions() function can be called recursively multiple
times while executing actions that require pipeline forking or
recirculations. It may also be re-entered multiple times if the packet
leaves openvswitch module and re-enters it through a different port.
Currently, there is a 256-byte array allocated on stack in this
function that is supposed to hold NSH header. Compilers tend to
pre-allocate that space right at the beginning of the function:
a88: 48 81 ec b0 01 00 00 sub $0x1b0,%rsp
NSH is not a very common protocol, but the space is allocated on every
recursive call or re-entry multiplying the wasted stack space.
Move the stack allocation to push_nsh() function that is only used
if NSH actions are actually present. push_nsh() is also a simple
function without a possibility for re-entry, so the stack is returned
right away.
With this change the preallocated space is reduced by 256 B per call:
b18: 48 81 ec b0 00 00 00 sub $0xb0,%rsp
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Eelco Chaudron echaudro@redhat.com
Reviewed-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/xdp/xsk.c')
0 files changed, 0 insertions, 0 deletions