Re: [PATCH net-next 04/15] net: page_pool: id the page pools

On Tue, 24 Oct 2023 at 19:02, Jakub Kicinski [off-list ref] wrote:

To give ourselves the flexibility of creating netlink commands
and ability to refer to page pool instances in uAPIs create
IDs for page pools.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 include/net/page_pool/types.h |  4 ++++
 net/core/Makefile             |  2 +-
 net/core/page_pool.c          | 21 +++++++++++++++-----
 net/core/page_pool_priv.h     |  9 +++++++++
 net/core/page_pool_user.c     | 36 +++++++++++++++++++++++++++++++++++
 5 files changed, 66 insertions(+), 6 deletions(-)
 create mode 100644 net/core/page_pool_priv.h
 create mode 100644 net/core/page_pool_user.c

[...]

+int page_pool_list(struct page_pool *pool)
+{
+       static u32 id_alloc_next;
+       int err;
+
+       mutex_lock(&page_pools_lock);
+       err = xa_alloc_cyclic(&page_pools, &pool->user.id, pool, xa_limit_32b,
+                             &id_alloc_next, GFP_KERNEL);
+       if (err < 0)
+               goto err_unlock;

A nit really, but get rid of the if/goto and just let this return err; ?

+
+       mutex_unlock(&page_pools_lock);
+       return 0;
+
+err_unlock:
+       mutex_unlock(&page_pools_lock);
+       return err;
+}
+
+void page_pool_unlist(struct page_pool *pool)
+{
+       mutex_lock(&page_pools_lock);
+       xa_erase(&page_pools, pool->user.id);
+       mutex_unlock(&page_pools_lock);
+}
--
2.41.0