Commit graph

4 commits

Author SHA1 Message Date
Eric Dumazet
e3d4825124 udp: move udp_memory_allocated into net_aligned_data
____cacheline_aligned_in_smp attribute only makes sure to align
a field to a cache line. It does not prevent the linker to use
the remaining of the cache line for other variables, causing
potential false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
Eric Dumazet
8308133741 tcp: move tcp_memory_allocated into net_aligned_data
____cacheline_aligned_in_smp attribute only makes sure to align
a field to a cache line. It does not prevent the linker to use
the remaining of the cache line for other variables, causing
potential false sharing.

Move tcp_memory_allocated into a dedicated cache line.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
Eric Dumazet
998642e999 net: move net_cookie into net_aligned_data
Using per-cpu data for net->net_cookie generation is overkill,
because even busy hosts do not create hundreds of netns per second.

Make sure to put net_cookie in a private cache line to avoid
potential false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00
Eric Dumazet
3715b5df09 net: add struct net_aligned_data
This structure will hold networking data that must
consume a full cache line to avoid accidental false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20250630093540.3052835-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-02 14:22:02 -07:00