From 7886cefe5ddd238c64d07eb037804f1aef24755c Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 19 Sep 2019 13:30:29 -0700 Subject: exec: Split out variable page size support to exec-vary.c MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The next patch will play a trick with "const" that will confuse the compiler about the uses of target_page_bits within exec.c. Moving everything to a new file prevents this confusion. No functional change so far. Reviewed-by: Alex Bennée Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Paolo Bonzini Signed-off-by: Richard Henderson --- exec-vary.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 exec-vary.c (limited to 'exec-vary.c') diff --git a/exec-vary.c b/exec-vary.c new file mode 100644 index 0000000000..48c0ab306c --- /dev/null +++ b/exec-vary.c @@ -0,0 +1,57 @@ +/* + * Variable page size handling + * + * Copyright (c) 2003 Fabrice Bellard + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, see . + */ + +#include "qemu/osdep.h" +#include "qemu-common.h" +#include "exec/exec-all.h" + +#ifdef TARGET_PAGE_BITS_VARY +int target_page_bits; +bool target_page_bits_decided; +#endif + +bool set_preferred_target_page_bits(int bits) +{ + /* + * The target page size is the lowest common denominator for all + * the CPUs in the system, so we can only make it smaller, never + * larger. And we can't make it smaller once we've committed to + * a particular size. + */ +#ifdef TARGET_PAGE_BITS_VARY + assert(bits >= TARGET_PAGE_BITS_MIN); + if (target_page_bits == 0 || target_page_bits > bits) { + if (target_page_bits_decided) { + return false; + } + target_page_bits = bits; + } +#endif + return true; +} + +void finalize_target_page_bits(void) +{ +#ifdef TARGET_PAGE_BITS_VARY + if (target_page_bits == 0) { + target_page_bits = TARGET_PAGE_BITS_MIN; + } + target_page_bits_decided = true; +#endif +} -- cgit v1.2.3