From 44c3b58cf9b2c91a38363f0b45d20f3f40b8f2b3 Mon Sep 17 00:00:00 2001 From: "Michael R. Hines" Date: Mon, 22 Jul 2013 10:01:53 -0400 Subject: rdma: introduce ram_handle_compressed() This gives RDMA shared access to madvise() on the destination side when an entire chunk is found to be zero. Reviewed-by: Juan Quintela Reviewed-by: Paolo Bonzini Reviewed-by: Chegu Vinod Tested-by: Chegu Vinod Tested-by: Michael R. Hines Signed-off-by: Michael R. Hines Signed-off-by: Juan Quintela --- arch_init.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) (limited to 'arch_init.c') diff --git a/arch_init.c b/arch_init.c index e9dd96fb28..09a712528e 100644 --- a/arch_init.c +++ b/arch_init.c @@ -808,6 +808,24 @@ static inline void *host_from_stream_offset(QEMUFile *f, return NULL; } +/* + * If a page (or a whole RDMA chunk) has been + * determined to be zero, then zap it. + */ +void ram_handle_compressed(void *host, uint8_t ch, uint64_t size) +{ + if (ch != 0 || !is_zero_page(host)) { + memset(host, ch, size); +#ifndef _WIN32 + if (ch == 0 && + (!kvm_enabled() || kvm_has_sync_mmu()) && + getpagesize() <= TARGET_PAGE_SIZE) { + qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED); + } +#endif + } +} + static int ram_load(QEMUFile *f, void *opaque, int version_id) { ram_addr_t addr; @@ -879,16 +897,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) } ch = qemu_get_byte(f); - if (ch != 0 || !is_zero_page(host)) { - memset(host, ch, TARGET_PAGE_SIZE); -#ifndef _WIN32 - if (ch == 0 && - (!kvm_enabled() || kvm_has_sync_mmu()) && - getpagesize() <= TARGET_PAGE_SIZE) { - qemu_madvise(host, TARGET_PAGE_SIZE, QEMU_MADV_DONTNEED); - } -#endif - } + ram_handle_compressed(host, ch, TARGET_PAGE_SIZE); } else if (flags & RAM_SAVE_FLAG_PAGE) { void *host; -- cgit v1.2.1