On Fri, May 31, 2024 at 08:37:41AM -0700, Shradha Gupta wrote:
> Allow variable size indirection table allocation in MANA instead
> of using a constant value MANA_INDIRECT_TABLE_SIZE.
> The size is now derived from the MANA_QUERY_VPORT_CONFIG and the
> indirection table is allocated dynamically.
>
> Signed-off-by: Shradha Gupta <shradhagu...@linux.microsoft.com>
> Reviewed-by: Dexuan Cui <de...@microsoft.com>
> Reviewed-by: Haiyang Zhang <haiya...@microsoft.com>
...
> diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c
> b/drivers/net/ethernet/microsoft/mana/mana_en.c
...
> @@ -2344,11 +2352,33 @@ static int mana_create_vport(struct mana_port_context
> *apc,
> return mana_create_txq(apc, net);
> }
>
> +static int mana_rss_table_alloc(struct mana_port_context *apc)
> +{
> + if (!apc->indir_table_sz) {
> + netdev_err(apc->ndev,
> + "Indirection table size not set for vPort %d\n",
> + apc->port_idx);
> + return -EINVAL;
> + }
> +
> + apc->indir_table = kcalloc(apc->indir_table_sz, sizeof(u32),
> GFP_KERNEL);
> + if (!apc->indir_table)
> + return -ENOMEM;
> +
> + apc->rxobj_table = kcalloc(apc->indir_table_sz, sizeof(mana_handle_t),
> GFP_KERNEL);
> + if (!apc->rxobj_table) {
> + kfree(apc->indir_table);
Hi, Shradha
Perhaps I am on the wrong track here, but I have some concerns
about clean-up paths.
Firstly. I think that apc->indir_table should be to NULL here for
consistency with other clean-up paths. Or alternatively, fields of apc
should not set to NULL elsewhere after being freed.
In looking into this I noticed that mana_probe() does not call
mana_remove() or return an error in the cases where mana_probe_port() or
mana_attach() fail unless add_adev also fails. If so, is that intentional?
In any case, I would suggest as a follow-up, arranging things so that when
an error occurs in a function, anything that was allocated is unwound
before returning an error.
I think this would make allocation/deallocation easier to reason with.
And I suspect it would avoid both the need for fields of structures to be
zeroed after being freed, and the need to call mana_remove() from
mana_probe().
> + return -ENOMEM;
> + }
> +
> + return 0;
> +}
> +
> static void mana_rss_table_init(struct mana_port_context *apc)
> {
> int i;
>
> - for (i = 0; i < MANA_INDIRECT_TABLE_SIZE; i++)
> + for (i = 0; i < apc->indir_table_sz; i++)
> apc->indir_table[i] =
> ethtool_rxfh_indir_default(i, apc->num_queues);
> }
...
> @@ -2739,11 +2772,17 @@ static int mana_probe_port(struct mana_context *ac,
> int port_idx,
> err = register_netdev(ndev);
> if (err) {
> netdev_err(ndev, "Unable to register netdev.\n");
> - goto reset_apc;
> + goto free_indir;
> }
>
> return 0;
>
> +free_indir:
> + apc->indir_table_sz = 0;
> + kfree(apc->indir_table);
> + apc->indir_table = NULL;
> + kfree(apc->rxobj_table);
> + apc->rxobj_table = NULL;
> reset_apc:
> kfree(apc->rxqs);
> apc->rxqs = NULL;
nit: Not strictly related to this patch, but the reset_apc code should
probably be a call to mana_cleanup_port_context() as it is the dual of
mana_init_port_context() which is called earlier in mana_probe_port()
...
> @@ -2931,6 +2972,11 @@ void mana_remove(struct gdma_dev *gd, bool suspending)
> }
>
> unregister_netdevice(ndev);
> + apc->indir_table_sz = 0;
> + kfree(apc->indir_table);
> + apc->indir_table = NULL;
> + kfree(apc->rxobj_table);
> + apc->rxobj_table = NULL;
The code to free and zero indir_table_sz and indir_table appears twice
in this patch. Perhaps a helper to do this, which would be the dual
of mana_rss_table_alloc is in order.
>
> rtnl_unlock();
>
...
