diff --git a/oslib-posix.c b/oslib-posix.c index 196099cc77..a304fb0f53 100644 --- a/oslib-posix.c +++ b/oslib-posix.c @@ -35,6 +35,13 @@ extern int daemon(int, int); #endif +#if defined(__linux__) && defined(__x86_64__) + /* Use 2MB alignment so transparent hugepages can be used by KVM */ +# define QEMU_VMALLOC_ALIGN (512 * 4096) +#else +# define QEMU_VMALLOC_ALIGN getpagesize() +#endif + #include "config-host.h" #include "sysemu.h" #include "trace.h" @@ -80,7 +87,12 @@ void *qemu_memalign(size_t alignment, size_t size) void *qemu_vmalloc(size_t size) { void *ptr; - ptr = qemu_memalign(getpagesize(), size); + size_t align = QEMU_VMALLOC_ALIGN; + + if (size < align) { + align = getpagesize(); + } + ptr = qemu_memalign(align, size); trace_qemu_vmalloc(size, ptr); return ptr; }