On 04.01.2025 02:58, Denis Mukhin via B4 Relay wrote:
> --- a/xen/drivers/char/console.c
> +++ b/xen/drivers/char/console.c
> @@ -40,6 +40,11 @@
> #include <asm/guest.h>
> #endif
>
> +/* Console flags. */
> +enum {
> + CONSOLE_RING = BIT(0, U),
> +};
These aren't console flags, but flags passed to the new console_write().
The comment wants adjusting accordingly, and I guess the enum would also
best move immediately ahead of the function.
> @@ -636,6 +641,16 @@ static void cf_check notify_dom0_con_ring(void *unused)
> static DECLARE_SOFTIRQ_TASKLET(notify_dom0_con_ring_tasklet,
> notify_dom0_con_ring, NULL);
>
> +static bool console_locks_busted;
> +
> +static void conring_write(const char *str, size_t len)
> +{
> + conring_puts(str, len);
> +
> + if ( !console_locks_busted )
> + tasklet_schedule(¬ify_dom0_con_ring_tasklet);
> +}
This doesn't really need to be a separate function, does it?
> @@ -644,8 +659,47 @@ static inline void xen_console_write_debug_port(const
> char *buf, size_t len)
> : "=&S" (tmp), "=&c" (tmp)
> : "0" (buf), "1" (len), "d" (XEN_HVM_DEBUGCONS_IOPORT) );
> }
> +
> +static void xen_console_write(const char *str, size_t len)
> +{
> + if ( xen_guest )
> + xen_hypercall_console_write(str, len);
> + else
> + xen_console_write_debug_port(str, len);
> +}
Nor does this, I suppose. The more that the sole call to here ...
> #endif
>
> +/*
> + * Write characters to console.
> + *
> + * That will handle all possible scenarios working w/ console
> + * - serial console;
> + * - VGA console (x86 only);
> + * - __HYPERVISOR_console_io hypercall (x86 only);
> + * - debug I/O port (x86 only);
> + * - PV console.
> + */
> +static void console_write(const char *str, size_t len, unsigned int flags)
> +{
> + ASSERT(rspin_is_locked(&console_lock));
> +
> + console_serial_puts(str, len);
> + video_puts(str, len);
> +
> +#ifdef CONFIG_X86
> + if ( opt_console_xen )
> + xen_console_write(str, len);
> +#endif
... continues to sit in an #ifdef.
> @@ -666,28 +720,8 @@ static long
> guest_console_write(XEN_GUEST_HANDLE_PARAM(char) buffer,
>
> if ( is_hardware_domain(cd) )
> {
> - /* Use direct console output as it could be interactive */
This comment looks like being removed with no replacement? Why?
> nrspin_lock_irq(&console_lock);
> -
> - console_serial_puts(kbuf, kcount);
> - video_puts(kbuf, kcount);
> -
> -#ifdef CONFIG_X86
> - if ( opt_console_xen )
> - {
> - if ( xen_guest )
> - xen_hypercall_console_write(kbuf, kcount);
> - else
> - xen_console_write_debug_port(kbuf, kcount);
> - }
> -#endif
> -
> - if ( opt_console_to_ring )
> - {
> - conring_puts(kbuf, kcount);
> - tasklet_schedule(¬ify_dom0_con_ring_tasklet);
> - }
> -
> + console_write(kbuf, kcount, !!opt_console_to_ring);
Here you assume CONSOLE_RING is bit 0. Please don't create such (then
also un-annotated) implicit dependencies.
> @@ -788,33 +822,6 @@ long do_console_io(
> * *****************************************************
> */
>
> -static bool console_locks_busted;
> -
> -static void __putstr(const char *str)
> -{
Please note the comment up from here, the tail of which is visible in
context. I wonder whether the new function wouldn't better live here,
then also reducing the diff quite a bit. Requiring a forward decl
for this to work isn't very nice, but a reasonable price to pay, I
think.
Jan
