From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49108) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eK7Rb-00016D-BA for qemu-devel@nongnu.org; Wed, 29 Nov 2017 13:50:52 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eK7Ra-0001Tl-25 for qemu-devel@nongnu.org; Wed, 29 Nov 2017 13:50:51 -0500 Received: from mx1.redhat.com ([209.132.183.28]:51880) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eK7RZ-0001TQ-Os for qemu-devel@nongnu.org; Wed, 29 Nov 2017 13:50:49 -0500 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C75FC80476 for ; Wed, 29 Nov 2017 18:50:48 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" Date: Wed, 29 Nov 2017 18:50:24 +0000 Message-Id: <20171129185026.23632-6-dgilbert@redhat.com> In-Reply-To: <20171129185026.23632-1-dgilbert@redhat.com> References: <20171129185026.23632-1-dgilbert@redhat.com> Subject: [Qemu-devel] [RFC 5/7] vhost: Compare new and old memory lists List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, imammedo@redhat.com Cc: maxime.coquelin@redhat.com, mst@redhat.com From: "Dr. David Alan Gilbert" Compare the memory section list we've just built with the old one and produce an upper/lower bound of addresses changed. Signed-off-by: Dr. David Alan Gilbert --- hw/virtio/trace-events | 3 ++ hw/virtio/vhost.c | 74 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 77 insertions(+) diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events index 92fadec192..ba85a1855b 100644 --- a/hw/virtio/trace-events +++ b/hw/virtio/trace-events @@ -2,6 +2,9 @@ # hw/virtio/vhost.c vhost_section(const char *name, int r) "%s:%d" +vhost_update_compare_list_loopn(int newi, int oldi, uint64_t gpa, uint64_t size) "%d/%d: (new) 0x%"PRIx64"+0x%"PRIx64 +vhost_update_compare_list_loopo(int newi, int oldi, uint64_t gpa, uint64_t size) "%d/%d: (old) 0x%"PRIx64"+0x%"PRIx64 +vhost_update_mem_comparison(bool update, uint64_t start, uint64_t end) "update: %d 0x%"PRIx64" - 0x%"PRIx64 vhost_update_mem_cb(const char *name, uint64_t gpa, uint64_t size, uint64_t host) "%s: 0x%"PRIx64"+0x%"PRIx64" @ 0x%"PRIx64 vhost_update_mem_cb_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx64 diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index 7e3c6ae032..ae3d57df1d 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -699,10 +699,79 @@ static int vhost_update_mem_cb(MemoryRegionSection *mrs, void *opaque) return 0; } +static bool vhost_update_compare_list(struct vhost_dev *dev, + struct vhost_update_mem_tmp *vtmp, + hwaddr *change_start, hwaddr *change_end) +{ + uint32_t oldi, newi; + *change_start = 0; + *change_end = 0; + + for (newi = 0, oldi = 0; newi < vtmp->nregions; newi++) { + struct vhost_memory_region *newr = &vtmp->regions[newi]; + hwaddr newr_last = range_get_last(newr->guest_phys_addr, + newr->memory_size); + trace_vhost_update_compare_list_loopn(newi, oldi, + newr->guest_phys_addr, + newr->memory_size); + bool whole_change = true; + while (oldi < dev->mem->nregions) { + struct vhost_memory_region *oldr = &dev->mem->regions[oldi]; + hwaddr oldr_last = range_get_last(oldr->guest_phys_addr, + oldr->memory_size); + trace_vhost_update_compare_list_loopo(newi, oldi, + oldr->guest_phys_addr, + oldr->memory_size); + if (newr->guest_phys_addr == oldr->guest_phys_addr && + newr->memory_size == oldr->memory_size) { + /* Match in GPA and size, but it could be different + * in host address or flags + */ + whole_change = newr->userspace_addr != oldr->userspace_addr || + newr->flags_padding != oldr->flags_padding; + oldi++; + break; /* inner old loop */ + } + /* There's a difference - need to figure out what */ + if (oldr_last < newr->guest_phys_addr) { + /* There used to be a region before us that's gone */ + *change_start = MIN(*change_start, oldr->guest_phys_addr); + *change_end = MAX(*change_end, oldr_last); + oldi++; + continue; /* inner old loop */ + } + if (oldr->guest_phys_addr > newr_last) { + /* We've passed all the old mappings that could have overlapped + * this one + */ + break; /* Inner old loop */ + } + /* Overlap case */ + *change_start = MIN(*change_start, + MIN(oldr->guest_phys_addr, + newr->guest_phys_addr)); + *change_end = MAX(*change_end, + MAX(oldr_last, newr_last)); + whole_change = false; + /* There might be more old mappings that overlap */ + oldi++; + } + if (whole_change) { + /* No old region to compare against, this must be a change */ + *change_start = MIN(*change_start, newr->guest_phys_addr); + *change_end = MAX(*change_end, newr_last); + } + } + + return *change_start || *change_end; +} + static int vhost_update_mem(struct vhost_dev *dev) { int res; struct vhost_update_mem_tmp vtmp; + hwaddr change_start, change_end; + bool need_update; vtmp.regions = 0; vtmp.nregions = 0; vtmp.dev = dev; @@ -713,6 +782,11 @@ static int vhost_update_mem(struct vhost_dev *dev) goto out; } + need_update = vhost_update_compare_list(dev, &vtmp, + &change_start, &change_end); + trace_vhost_update_mem_comparison(need_update, + (uint64_t)change_start, + (uint64_t)change_end); /* TODO */ out: g_free(vtmp.regions); -- 2.14.3