Re: [Xen-devel] [PATCH v4 3/5] xen: Put EFI machinery in place

From: Andrew Cooper
Date: Mon May 19 2014 - 09:39:11 EST


On 16/05/14 21:41, Daniel Kiper wrote:
> @@ -0,0 +1,374 @@
> +/*
> + * EFI support for Xen.
> + *
> + * Copyright (C) 1999 VA Linux Systems
> + * Copyright (C) 1999 Walt Drummond <drummond@xxxxxxxxxxx>
> + * Copyright (C) 1999-2002 Hewlett-Packard Co.
> + * David Mosberger-Tang <davidm@xxxxxxxxxx>
> + * Stephane Eranian <eranian@xxxxxxxxxx>
> + * Copyright (C) 2005-2008 Intel Co.
> + * Fenghua Yu <fenghua.yu@xxxxxxxxx>
> + * Bibo Mao <bibo.mao@xxxxxxxxx>
> + * Chandramouli Narayanan <mouli@xxxxxxxxxxxxxxx>
> + * Huang Ying <ying.huang@xxxxxxxxx>
> + * Copyright (C) 2011 Novell Co.
> + * Jan Beulich <JBeulich@xxxxxxxx>
> + * Copyright (C) 2011-2012 Oracle Co.
> + * Liang Tang <liang.tang@xxxxxxxxxx>
> + * Copyright (c) 2014 Daniel Kiper, Oracle Corporation
> + */
> +
> +#include <linux/bug.h>
> +#include <linux/efi.h>
> +#include <linux/init.h>
> +#include <linux/string.h>
> +
> +#include <xen/interface/xen.h>
> +#include <xen/interface/platform.h>
> +
> +#include <asm/xen/hypercall.h>
> +
> +#define call (op.u.efi_runtime_call)

I think not.

> +#define DECLARE_CALL(what) \
> + struct xen_platform_op op; \
> + op.cmd = XENPF_efi_runtime_call; \
> + call.function = XEN_EFI_##what; \
> + call.misc = 0

Macros like this which explicitly create local variable with implicit
names are evil when reading code.

If you want to do initialisation like this, then at least do something like:

#define INIT_EFI_CALL(what) \
{ .cmd = XENPF_efi_runtime_call, \
.u.efi_runtime_call.function = XEN_EFI_##what, \
.u.efi_runtime_call.misc = 0 }

And use it as:

struct xen_platform_op op = INIT_EFI_CALL(foo);

~Andrew
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/