Author: hselasky Date: Thu Aug 3 14:09:36 2017 New Revision: 322005 URL: https://svnweb.freebsd.org/changeset/base/322005
Log: MFC r312865: Enforce reading the consumer and producer counters once to ensure consistent return values from the mlx5e_sq_has_room_for() function. The two counters are incremented by different threads under different locks. Sponsored by: Mellanox Technologies Modified: stable/10/sys/dev/mlx5/mlx5_en/en.h Directory Properties: stable/10/ (props changed) Modified: stable/10/sys/dev/mlx5/mlx5_en/en.h ============================================================================== --- stable/10/sys/dev/mlx5/mlx5_en/en.h Thu Aug 3 14:08:39 2017 (r322004) +++ stable/10/sys/dev/mlx5/mlx5_en/en.h Thu Aug 3 14:09:36 2017 (r322005) @@ -556,8 +556,10 @@ struct mlx5e_sq { static inline bool mlx5e_sq_has_room_for(struct mlx5e_sq *sq, u16 n) { - return ((sq->wq.sz_m1 & (sq->cc - sq->pc)) >= n || - sq->cc == sq->pc); + u16 cc = sq->cc; + u16 pc = sq->pc; + + return ((sq->wq.sz_m1 & (cc - pc)) >= n || cc == pc); } struct mlx5e_channel { _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"