From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:33588) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aP5QR-0007RZ-8o for qemu-devel@nongnu.org; Fri, 29 Jan 2016 04:33:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aP5QN-0000Lk-18 for qemu-devel@nongnu.org; Fri, 29 Jan 2016 04:33:07 -0500 Received: from mail-wm0-x22a.google.com ([2a00:1450:400c:c09::22a]:33600) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aP5QM-0000Kp-NS for qemu-devel@nongnu.org; Fri, 29 Jan 2016 04:33:02 -0500 Received: by mail-wm0-x22a.google.com with SMTP id l66so59259463wml.0 for ; Fri, 29 Jan 2016 01:33:02 -0800 (PST) From: Alvise Rigo Date: Fri, 29 Jan 2016 10:32:30 +0100 Message-Id: <1454059965-23402-2-git-send-email-a.rigo@virtualopensystems.com> In-Reply-To: <1454059965-23402-1-git-send-email-a.rigo@virtualopensystems.com> References: <1454059965-23402-1-git-send-email-a.rigo@virtualopensystems.com> Subject: [Qemu-devel] [RFC v7 01/16] exec.c: Add new exclusive bitmap to ram_list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, mttcg@listserver.greensocs.com Cc: claudio.fontana@huawei.com, pbonzini@redhat.com, jani.kokkonen@huawei.com, tech@virtualopensystems.com, alex.bennee@linaro.org, rth@twiddle.net The purpose of this new bitmap is to flag the memory pages that are in the middle of LL/SC operations (after a LL, before a SC). For all these pages, the corresponding TLB entries will be generated in such a way to force the slow-path for all the VCPUs (see the following patches). When the system starts, the whole memory is set to dirty. Suggested-by: Jani Kokkonen Suggested-by: Claudio Fontana Signed-off-by: Alvise Rigo --- exec.c | 7 +++++-- include/exec/memory.h | 3 ++- include/exec/ram_addr.h | 31 +++++++++++++++++++++++++++++++ 3 files changed, 38 insertions(+), 3 deletions(-) diff --git a/exec.c b/exec.c index 7115403..51f366d 100644 --- a/exec.c +++ b/exec.c @@ -1575,11 +1575,14 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp) int i; /* ram_list.dirty_memory[] is protected by the iothread lock. */ - for (i = 0; i < DIRTY_MEMORY_NUM; i++) { + for (i = 0; i < DIRTY_MEMORY_EXCLUSIVE; i++) { ram_list.dirty_memory[i] = bitmap_zero_extend(ram_list.dirty_memory[i], old_ram_size, new_ram_size); - } + } + ram_list.dirty_memory[DIRTY_MEMORY_EXCLUSIVE] = + bitmap_zero_extend(ram_list.dirty_memory[DIRTY_MEMORY_EXCLUSIVE], + old_ram_size, new_ram_size); } cpu_physical_memory_set_dirty_range(new_block->offset, new_block->used_length, diff --git a/include/exec/memory.h b/include/exec/memory.h index c92734a..71e0480 100644 --- a/include/exec/memory.h +++ b/include/exec/memory.h @@ -19,7 +19,8 @@ #define DIRTY_MEMORY_VGA 0 #define DIRTY_MEMORY_CODE 1 #define DIRTY_MEMORY_MIGRATION 2 -#define DIRTY_MEMORY_NUM 3 /* num of dirty bits */ +#define DIRTY_MEMORY_EXCLUSIVE 3 +#define DIRTY_MEMORY_NUM 4 /* num of dirty bits */ #include #include diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h index ef1489d..19789fc 100644 --- a/include/exec/ram_addr.h +++ b/include/exec/ram_addr.h @@ -21,6 +21,7 @@ #ifndef CONFIG_USER_ONLY #include "hw/xen/xen.h" +#include "sysemu/sysemu.h" struct RAMBlock { struct rcu_head rcu; @@ -172,6 +173,9 @@ static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start, if (unlikely(mask & (1 << DIRTY_MEMORY_CODE))) { bitmap_set_atomic(d[DIRTY_MEMORY_CODE], page, end - page); } + if (unlikely(mask & (1 << DIRTY_MEMORY_EXCLUSIVE))) { + bitmap_set_atomic(d[DIRTY_MEMORY_EXCLUSIVE], page, end - page); + } xen_modified_memory(start, length); } @@ -287,5 +291,32 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest, } void migration_bitmap_extend(ram_addr_t old, ram_addr_t new); + +/* Exclusive bitmap support. */ +#define EXCL_BITMAP_GET_OFFSET(addr) (addr >> TARGET_PAGE_BITS) + +/* Make the page of @addr not exclusive. */ +static inline void cpu_physical_memory_unset_excl(ram_addr_t addr) +{ + set_bit_atomic(EXCL_BITMAP_GET_OFFSET(addr), + ram_list.dirty_memory[DIRTY_MEMORY_EXCLUSIVE]); +} + +/* Return true if the page of @addr is exclusive, i.e. the EXCL bit is set. */ +static inline int cpu_physical_memory_is_excl(ram_addr_t addr) +{ + return !test_bit(EXCL_BITMAP_GET_OFFSET(addr), + ram_list.dirty_memory[DIRTY_MEMORY_EXCLUSIVE]); +} + +/* Set the page of @addr as exclusive clearing its EXCL bit and return the + * previous bit's state. */ +static inline int cpu_physical_memory_set_excl(ram_addr_t addr) +{ + return bitmap_test_and_clear_atomic( + ram_list.dirty_memory[DIRTY_MEMORY_EXCLUSIVE], + EXCL_BITMAP_GET_OFFSET(addr), 1); +} + #endif #endif -- 2.7.0