]> www.infradead.org Git - users/dwmw2/linux.git/commit
nfp: use irq_update_affinity_hint()
authorMohammad Heib <mheib@redhat.com>
Thu, 7 Nov 2024 11:50:02 +0000 (13:50 +0200)
committerJakub Kicinski <kuba@kernel.org>
Mon, 11 Nov 2024 23:32:18 +0000 (15:32 -0800)
commitd9e2e290f7142d4c67c05ebbe37388d54a66c6c5
tree3becea5a89d62e4e4eda6331793f07e90afd8a34
parentfcf42409c6e15e47186de8bb051176aaf92c597a
nfp: use irq_update_affinity_hint()

irq_set_affinity_hint() is deprecated, Use irq_update_affinity_hint()
instead. This removes the side-effect of actually applying the affinity.

The driver does not really need to worry about spreading its IRQs across
CPUs. The core code already takes care of that. when the driver applies the
affinities by itself, it breaks the users' expectations:

1. The user configures irqbalance with IRQBALANCE_BANNED_CPULIST in
   order to prevent IRQs from being moved to certain CPUs that run a
   real-time workload.

2. nfp device reopening will resets the affinity
   in nfp_net_netdev_open().

3. nfp has no idea about irqbalance's config, so it may move an IRQ to
   a banned CPU. The real-time workload suffers unacceptable latency.

Signed-off-by: Mohammad Heib <mheib@redhat.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Louis Peens <louis.peens@corigine.com>
Link: https://patch.msgid.link/20241107115002.413358-1-mheib@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
drivers/net/ethernet/netronome/nfp/nfp_net_common.c