xen: remove GNUC check

QEMU requires Clang or GCC, that define and support __GNUC__ extensions

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Message-Id: <20201210134752.780923-11-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Marc-André Lureau 2020-12-10 17:47:49 +04:00 committed by Paolo Bonzini
parent b8f02d1616
commit d55e5bd15a

View File

@ -206,21 +206,12 @@ typedef struct __name##_back_ring __name##_back_ring_t
#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
((_r)->sring->rsp_prod - (_r)->rsp_cons)
#ifdef __GNUC__
#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
unsigned int rsp = RING_SIZE(_r) - \
((_r)->req_cons - (_r)->rsp_prod_pvt); \
req < rsp ? req : rsp; \
})
#else
/* Same as above, but without the nice GCC ({ ... }) syntax. */
#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
((((_r)->sring->req_prod - (_r)->req_cons) < \
(RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
((_r)->sring->req_prod - (_r)->req_cons) : \
(RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
#endif
/* Direct access to individual ring elements, by index. */
#define RING_GET_REQUEST(_r, _idx) \