On 17 Oct 2025, at 19:11, Ilya Maximets wrote:
> This annotation never worked on structure fields, but it does now with
> clang 21. The problem is that structures like cmap or rculist are
> designed for lockless access for readers and so we're not holding any
> locks while reading. That makes new clang generate thread-safety
> warnings:
>
> lib/dpif-netdev.c:3632:40:
> warning: reading the value pointed to by 'flow_table' requires
> holding any mutex [-Wthread-safety-analysis]
> 3632 | &pmd->flow_table) {
> | ^
>
> Signed-off-by: Ilya Maximets <[email protected]>
Thanks for fixing these. The change looks good to me and tested with clang21.
Two nits below ;)
Cheers,
Eelco
Acked-by: Eelco Chaudron <[email protected]>
<snip>
> diff --git a/lib/dpif-netdev-private-dpcls.h b/lib/dpif-netdev-private-dpcls.h
> index 2a9279437..03f07c621 100644
> --- a/lib/dpif-netdev-private-dpcls.h
> +++ b/lib/dpif-netdev-private-dpcls.h
> @@ -66,7 +66,7 @@ uint32_t (*dpcls_subtable_lookup_func)(struct
> dpcls_subtable *subtable,
> /* A set of rules that all have the same fields wildcarded. */
> struct dpcls_subtable {
> /* The fields are only used by writers. */
> - struct cmap_node cmap_node OVS_GUARDED; /* Within dpcls 'subtables_map'.
> */
> + struct cmap_node cmap_node; /* Within dpcls 'subtables_map'. */
Maybe add one space to align the comment with the ones below?
<snip>
> diff --git a/lib/dpif-netdev-private-thread.h
> b/lib/dpif-netdev-private-thread.h
> index 8715b3837..1992ba44b 100644
> --- a/lib/dpif-netdev-private-thread.h
> +++ b/lib/dpif-netdev-private-thread.h
> @@ -92,13 +92,13 @@ struct dp_netdev_pmd_thread {
> * made while still holding the 'flow_mutex'.
> */
> struct ovs_mutex flow_mutex;
> - struct cmap flow_table OVS_GUARDED; /* Flow table. */
> - struct cmap simple_match_table OVS_GUARDED; /* Flow table with simple
> - match flows only. */
> + struct cmap flow_table; /* Flow table. */
> + struct cmap simple_match_table; /* Flow table with simple
> + * match flows only. */
Remove space before match to align comments. Or maybe change the comment to fit
on a single line;
struct cmap simple_match_table; /* Flow table with simple match flows. */
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev
