Replace the test-and-set spinlock implementation with ticket locks
in order to get fairness (in form of FIFO order).
The implementation uses a 32-bit wide struct, which consists of
two 16-bit counters (owner and next). This is inspired by similar
spinlock implementations on other architectures.
This allows that the code works for both, RV32 and RV64.
Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
Reviewed-by: Xiang W <wxjstz@126.com>
The current implementation of SPIN_LOCK_INIT() provides the spinlock
to be initialized as reference. This does not allow a direct
initialization of the spinlock object at the creation site.
Let's pass the spinlock directly instead (like Linux does as well)
and adjust all users of the macro (in fact there is only one user).
Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
The __aligned(x) macro is a common wrapper around compiler's
aligned attribute, which allow to define the minimum alignement
of a data type. Let's add this macro.
Signed-off-by: Christoph Muellner <cmuellner@linux.com>
Reviewed-by: Anup Patel <anup.patel@wdc.com>
