net/mlx5e: RX, Fix page_pool allocation failure recovery for legacy rq

net/mlx5e: RX, Fix page_pool allocation failure recovery for legacy rq

When a page allocation fails during refill in mlx5e_refill_rx_wqes, the
page will be released again on the next refill call. This triggers the
page_pool negative page fragment count warning below:

 [  338.326070] WARNING: CPU: 4 PID: 0 at include/net/page_pool/helpers.h:130 mlx5e_page_release_fragmented.isra.0+0x42/0x50 [mlx5_core]
  ...
 [  338.328993] RIP: 0010:mlx5e_page_release_fragmented.isra.0+0x42/0x50 [mlx5_core]
 [  338.329094] Call Trace:
 [  338.329097]  <IRQ>
 [  338.329100]  ? __warn+0x7d/0x120
 [  338.329105]  ? mlx5e_page_release_fragmented.isra.0+0x42/0x50 [mlx5_core]
 [  338.329173]  ? report_bug+0x155/0x180
 [  338.329179]  ? handle_bug+0x3c/0x60
 [  338.329183]  ? exc_invalid_op+0x13/0x60
 [  338.329187]  ? asm_exc_invalid_op+0x16/0x20
 [  338.329192]  ? mlx5e_page_release_fragmented.isra.0+0x42/0x50 [mlx5_core]
 [  338.329259]  mlx5e_post_rx_wqes+0x210/0x5a0 [mlx5_core]
 [  338.329327]  ? mlx5e_poll_rx_cq+0x88/0x6f0 [mlx5_core]
 [  338.329394]  mlx5e_napi_poll+0x127/0x6b0 [mlx5_core]
 [  338.329461]  __napi_poll+0x25/0x1a0
 [  338.329465]  net_rx_action+0x28a/0x300
 [  338.329468]  __do_softirq+0xcd/0x279
 [  338.329473]  irq_exit_rcu+0x6a/0x90
 [  338.329477]  common_interrupt+0x82/0xa0
 [  338.329482]  </IRQ>

This patch fixes the legacy rq case by releasing all allocated fragments
and then setting the skip flag on all released fragments. It is
important to note that the number of released fragments will be higher
than the number of allocated fragments when an allocation error occurs.

Fixes: 3f93f82988bc ("net/mlx5e: RX, Defer page release in legacy rq for better recycling")
Tested-by: Chris Mason <clm@fb.com>
Reported-by: Chris Mason <clm@fb.com>
Closes: https://lore.kernel.org/netdev/117FF31A-7BE0-4050-B2BB-E41F224FF72F@meta.com
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>