On 05/13/2015 11:57 PM, Ian Campbell wrote:
On Wed, 2015-05-13 at 09:53 +0800, Yang Hongyang wrote:
There are cases that we only need to use the hypercall buffer data,
"cases where"
and do not use the xc_hypercall_buffer_t struct.
DECLARE_HYPERCALL_BUFFER_SHADOW define a user pointer that can allow
"defines a user pointer"
us to access the hypercall buffer data but it also define a
"defines"
xc_hypercall_buffer_t that we don't use, the compiler will report arg
unused error.
add __attribute__((unused)) before xc_hypercall_buffer_t to avoid
the compiler error.
The cases for example:
"Example cases:"
In send_all_pages(), we only need to use the haypercall buffer data
"hypercall"
which is a dirty bitmap, we set the dirty bitmap to all dirty and call
send_dirty_pages, we will not use the xc_hypercall_buffer_t and hypercall
to retrive the dirty bitmap.
"retrieve"
In send_some_pages(), we will also only need to use the dirty_bitmap.
the retrive dirty bitmap hypercall are done by the caller.
and again.
Signed-off-by: Yang Hongyang <yan...@cn.fujitsu.com>
CC: Ian Campbell <ian.campb...@citrix.com>
CC: Ian Jackson <ian.jack...@eu.citrix.com>
CC: Wei Liu <wei.l...@citrix.com>
CC: Andrew Cooper <andrew.coop...@citrix.com>
---
tools/libxc/include/xenctrl.h | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/tools/libxc/include/xenctrl.h b/tools/libxc/include/xenctrl.h
index a689caf..0804257 100644
--- a/tools/libxc/include/xenctrl.h
+++ b/tools/libxc/include/xenctrl.h
@@ -284,11 +284,15 @@ typedef struct xc_hypercall_buffer xc_hypercall_buffer_t;
* Useful when a hypercall buffer is passed to a function and access
* via the user pointer is required.
*
+ * The shadow xc_hypercall_buffer_t may be unused, add
+ * __attribute__((unused)) to avoid compiler error.
No need for this comment IMHO.
* See DECLARE_HYPERCALL_BUFFER_ARGUMENT() if the user pointer is not
* required.
*/
#define DECLARE_HYPERCALL_BUFFER_SHADOW(_type, _name, _hbuf) \
_type *(_name) = (_hbuf)->hbuf; \
+ __attribute__((unused)) \
This is a somewhat unconventional location for such a tagm but putting
it elsewhere would involve faff-some rewrapping.
So apart from the typos looks good.
Will fix those typos, thank you!
xc_hypercall_buffer_t XC__HYPERCALL_BUFFER_NAME(_name) = { \
.hbuf = (void *)-1, \
.param_shadow = (_hbuf), \
.
--
Thanks,
Yang.
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