On Tue, 9 Jan 2024 11:37:45 -0800 Elliot Berman <quic_eberman@xxxxxxxxxxx>
> +
> +static irqreturn_t gunyah_rm_tx(int irq, void *data)
> +{
> + struct gunyah_rm *rm = data;
> +
> + complete_all(&rm->send_ready);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int gunyah_rm_msgq_send(struct gunyah_rm *rm, size_t size, bool push)
> + __must_hold(&rm->send_lock)
> +{
> + const u64 tx_flags = push ? GUNYAH_HYPERCALL_MSGQ_TX_FLAGS_PUSH : 0;
> + enum gunyah_error gunyah_error;
> + void *data = &rm->send_msg[0];
> + bool ready;
lockdep_assert_held(&rm->send_lock); instead of __must_hold
> +
> +again:
> + wait_for_completion(&rm->send_ready);
> + /* reinit completion before hypercall. As soon as hypercall returns, we could get the
> + * ready interrupt. This might be before we have time to reinit the completion
> + */
> + reinit_completion(&rm->send_ready);
Given wait_for_completion(&rm->send_ready) with rm->send_lock held,
complete(&rm->send_ready) works for you with the bonus of cutting this
reinit off.
> + gunyah_error = gunyah_hypercall_msgq_send(rm->tx_ghrsc.capid, size,
> + data, tx_flags, &ready);
> +
> + /* Should never happen because Linux properly tracks the ready-state of the msgq */
> + if (WARN_ON(gunyah_error == GUNYAH_ERROR_MSGQUEUE_FULL))
> + goto again;
> +
> + if (ready)
> + complete_all(&rm->send_ready);
> +
> + return gunyah_error_remap(gunyah_error);
> +}
