> -----Original Message----- > From: Michael S. Tsirkin [mailto:m...@redhat.com] > Sent: Friday, March 02, 2018 12:17 AM > To: Zhoujian (jay) <jianjay.z...@huawei.com> > Cc: qemu-devel@nongnu.org; imamm...@redhat.com; Huangweidong (C) > <weidong.hu...@huawei.com>; wangxin (U) <wangxinxin.w...@huawei.com>; Gonglei > (Arei) <arei.gong...@huawei.com>; Liuzhe (Ahriy, Euler) <liuzh...@huawei.com> > Subject: Re: [PATCH v8 2/2] vhost: used_memslots refactoring > > On Tue, Feb 27, 2018 at 03:10:05PM +0800, Jay Zhou wrote: > > Used_memslots is shared by vhost kernel and user, it is equal to > > dev->mem->nregions, which is correct for vhost kernel, but not for > > vhost user, the latter one uses memory regions that have file > > descriptor. E.g. a VM has a vhost-user NIC and 8(vhost user memslot > > upper limit) memory slots, it will be failed to hotplug a new DIMM > > device since vhost_has_free_slot() finds no free slot left. It should > > be successful if only part of memory slots have file descriptor, so > > setting used memslots for vhost-user and vhost-kernel respectively. > > > > Signed-off-by: Igor Mammedov <imamm...@redhat.com> > > Signed-off-by: Jay Zhou <jianjay.z...@huawei.com> > > Signed-off-by: Liuzhe <liuzh...@huawei.com> > > make check fails with this patch, I dropped it for now.
Hi Michael, pls see the reason inline. > > > --- > > hw/virtio/vhost-backend.c | 15 +++++++- > > hw/virtio/vhost-user.c | 77 ++++++++++++++++++++++++++--------- > ---- > > hw/virtio/vhost.c | 13 +++---- > > include/hw/virtio/vhost-backend.h | 6 ++- > > 4 files changed, 75 insertions(+), 36 deletions(-) > > > > diff --git a/hw/virtio/vhost-backend.c b/hw/virtio/vhost-backend.c > > index 7f09efa..59def69 100644 > > --- a/hw/virtio/vhost-backend.c > > +++ b/hw/virtio/vhost-backend.c > > @@ -15,6 +15,8 @@ > > #include "hw/virtio/vhost-backend.h" > > #include "qemu/error-report.h" > > > > +static unsigned int vhost_kernel_used_memslots; > > + > > static int vhost_kernel_call(struct vhost_dev *dev, unsigned long int > request, > > void *arg) { @@ -62,6 +64,11 @@ static > > int vhost_kernel_memslots_limit(struct vhost_dev *dev) > > return limit; > > } > > > > +static bool vhost_kernel_has_free_memslots(struct vhost_dev *dev) { > > + return vhost_kernel_used_memslots < > > +vhost_kernel_memslots_limit(dev); } > > + > > static int vhost_kernel_net_set_backend(struct vhost_dev *dev, > > struct vhost_vring_file > > *file) { @@ -233,11 +240,16 @@ static void > > vhost_kernel_set_iotlb_callback(struct vhost_dev *dev, > > qemu_set_fd_handler((uintptr_t)dev->opaque, NULL, NULL, > > NULL); } > > > > +static void vhost_kernel_set_used_memslots(struct vhost_dev *dev) { > > + vhost_kernel_used_memslots = dev->mem->nregions; } > > + > > static const VhostOps kernel_ops = { > > .backend_type = VHOST_BACKEND_TYPE_KERNEL, > > .vhost_backend_init = vhost_kernel_init, > > .vhost_backend_cleanup = vhost_kernel_cleanup, > > - .vhost_backend_memslots_limit = vhost_kernel_memslots_limit, > > + .vhost_backend_has_free_memslots = > > + vhost_kernel_has_free_memslots, > > .vhost_net_set_backend = vhost_kernel_net_set_backend, > > .vhost_scsi_set_endpoint = vhost_kernel_scsi_set_endpoint, > > .vhost_scsi_clear_endpoint = > > vhost_kernel_scsi_clear_endpoint, @@ -264,6 +276,7 @@ static const > > VhostOps kernel_ops = { #endif /* CONFIG_VHOST_VSOCK */ > > .vhost_set_iotlb_callback = vhost_kernel_set_iotlb_callback, > > .vhost_send_device_iotlb_msg = > > vhost_kernel_send_device_iotlb_msg, > > + .vhost_set_used_memslots = vhost_kernel_set_used_memslots, > > }; > > > > int vhost_set_backend_type(struct vhost_dev *dev, VhostBackendType > > backend_type) diff --git a/hw/virtio/vhost-user.c > > b/hw/virtio/vhost-user.c index 6eb9798..f732c80 100644 > > --- a/hw/virtio/vhost-user.c > > +++ b/hw/virtio/vhost-user.c > > @@ -147,6 +147,8 @@ static VhostUserMsg m __attribute__ ((unused)); > > /* The version of the protocol we support */ > > #define VHOST_USER_VERSION (0x1) > > > > +static bool vhost_user_free_memslots = true; > > + > > struct vhost_user { > > CharBackend *chr; > > int slave_fd; > > @@ -314,12 +316,43 @@ static int vhost_user_set_log_base(struct vhost_dev > *dev, uint64_t base, > > return 0; > > } > > > > +static int vhost_user_prepare_msg(struct vhost_dev *dev, VhostUserMemory > *mem, > > + int *fds) { > > + int i, fd; > > + > > + vhost_user_free_memslots = true; > > + for (i = 0, mem->nregions = 0; i < dev->mem->nregions; ++i) { > > + struct vhost_memory_region *reg = dev->mem->regions + i; > > + ram_addr_t offset; > > + MemoryRegion *mr; > > + > > + assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); > > + mr = memory_region_from_host((void *)(uintptr_t)reg- > >userspace_addr, > > + &offset); > > + fd = memory_region_get_fd(mr); > > + if (fd > 0) { > > + if (mem->nregions == VHOST_MEMORY_MAX_NREGIONS) { > > + vhost_user_free_memslots = false; > > + return -1; > > + } > > + > > + mem->regions[mem->nregions].userspace_addr = reg- > >userspace_addr; > > + mem->regions[mem->nregions].memory_size = reg->memory_size; > > + mem->regions[mem->nregions].guest_phys_addr = reg- > >guest_phys_addr; > > + mem->regions[mem->nregions].mmap_offset = offset; > > + fds[mem->nregions++] = fd; > > + } > > + } > > + > > + return 0; > > +} > > + > > static int vhost_user_set_mem_table(struct vhost_dev *dev, > > struct vhost_memory *mem) { > > int fds[VHOST_MEMORY_MAX_NREGIONS]; > > - int i, fd; > > - size_t fd_num = 0; > > + size_t fd_num; > > bool reply_supported = virtio_has_feature(dev->protocol_features, > > > > VHOST_USER_PROTOCOL_F_REPLY_ACK); > > > > @@ -332,29 +365,12 @@ static int vhost_user_set_mem_table(struct vhost_dev > *dev, > > msg.hdr.flags |= VHOST_USER_NEED_REPLY_MASK; > > } > > > > - for (i = 0; i < dev->mem->nregions; ++i) { > > - struct vhost_memory_region *reg = dev->mem->regions + i; > > - ram_addr_t offset; > > - MemoryRegion *mr; > > - > > - assert((uintptr_t)reg->userspace_addr == reg->userspace_addr); > > - mr = memory_region_from_host((void *)(uintptr_t)reg- > >userspace_addr, > > - &offset); > > - fd = memory_region_get_fd(mr); > > - if (fd > 0) { > > - if (fd_num == VHOST_MEMORY_MAX_NREGIONS) { > > - error_report("Failed preparing vhost-user memory table > msg"); > > - return -1; > > - } > > - msg.payload.memory.regions[fd_num].userspace_addr = reg- > >userspace_addr; > > - msg.payload.memory.regions[fd_num].memory_size = reg- > >memory_size; > > - msg.payload.memory.regions[fd_num].guest_phys_addr = reg- > >guest_phys_addr; > > - msg.payload.memory.regions[fd_num].mmap_offset = offset; > > - fds[fd_num++] = fd; > > - } > > + if (vhost_user_prepare_msg(dev, &msg.payload.memory, fds) < 0) { > > + error_report("Failed preparing vhost-user memory table msg"); > > + return -1; > > } > > > > - msg.payload.memory.nregions = fd_num; > > + fd_num = msg.payload.memory.nregions; > > > > if (!fd_num) { > > error_report("Failed initializing vhost-user memory map, " > > @@ -870,9 +886,9 @@ static int vhost_user_get_vq_index(struct vhost_dev > *dev, int idx) > > return idx; > > } > > > > -static int vhost_user_memslots_limit(struct vhost_dev *dev) > > +static bool vhost_user_has_free_memslots(struct vhost_dev *dev) > > { > > - return VHOST_MEMORY_MAX_NREGIONS; > > + return vhost_user_free_memslots; > > } > > > > static bool vhost_user_requires_shm_log(struct vhost_dev *dev) @@ > > -1054,11 +1070,19 @@ static int vhost_user_set_config(struct vhost_dev *dev, > const uint8_t *data, > > return 0; > > } > > > > +static void vhost_user_set_used_memslots(struct vhost_dev *dev) { > > + int fds[VHOST_MEMORY_MAX_NREGIONS]; > > + VhostUserMsg msg; > > + > > + vhost_user_prepare_msg(dev, &msg.payload.memory, fds); } > > + > > const VhostOps user_ops = { > > .backend_type = VHOST_BACKEND_TYPE_USER, > > .vhost_backend_init = vhost_user_init, > > .vhost_backend_cleanup = vhost_user_cleanup, > > - .vhost_backend_memslots_limit = vhost_user_memslots_limit, > > + .vhost_backend_has_free_memslots = > > + vhost_user_has_free_memslots, > > .vhost_set_log_base = vhost_user_set_log_base, > > .vhost_set_mem_table = vhost_user_set_mem_table, > > .vhost_set_vring_addr = vhost_user_set_vring_addr, @@ -1082,4 > > +1106,5 @@ const VhostOps user_ops = { > > .vhost_send_device_iotlb_msg = vhost_user_send_device_iotlb_msg, > > .vhost_get_config = vhost_user_get_config, > > .vhost_set_config = vhost_user_set_config, > > + .vhost_set_used_memslots = vhost_user_set_used_memslots, > > }; > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index > > 4a583a3..7f17de9 100644 > > --- a/hw/virtio/vhost.c > > +++ b/hw/virtio/vhost.c > > @@ -44,20 +44,19 @@ > > static struct vhost_log *vhost_log; > > static struct vhost_log *vhost_log_shm; > > > > -static unsigned int used_memslots; > > static QLIST_HEAD(, vhost_dev) vhost_devices = > > QLIST_HEAD_INITIALIZER(vhost_devices); > > > > bool vhost_has_free_slot(void) > > { > > - unsigned int slots_limit = ~0U; > > struct vhost_dev *hdev; > > > > QLIST_FOREACH(hdev, &vhost_devices, entry) { > > - unsigned int r = hdev->vhost_ops- > >vhost_backend_memslots_limit(hdev); > > - slots_limit = MIN(slots_limit, r); > > + if (!hdev->vhost_ops->vhost_backend_has_free_memslots(hdev)) { > > + return false; > > + } > > } > > - return slots_limit > used_memslots; > > + return true; > > } > > > > static void vhost_dev_sync_region(struct vhost_dev *dev, @@ -442,7 > > +441,7 @@ static void vhost_commit(MemoryListener *listener) > > dev->n_mem_sections * sizeof dev->mem->regions[0]; > > dev->mem = g_realloc(dev->mem, regions_size); > > dev->mem->nregions = dev->n_mem_sections; > > - used_memslots = dev->mem->nregions; > > + dev->vhost_ops->vhost_set_used_memslots(dev); Since vhost_set_used_memslots() using the information of dev->mem->regions, so it should be called after updating dev->mem->regions(the for loop below), I have fixed this in v9. Regards, Jay > > for (i = 0; i < dev->n_mem_sections; i++) { > > struct vhost_memory_region *cur_vmr = dev->mem->regions + i; > > struct MemoryRegionSection *mrs = dev->mem_sections + i; @@ > > -1186,7 +1185,7 @@ int vhost_dev_init(struct vhost_dev *hdev, void *opaque, > > memory_listener_register(&hdev->memory_listener, > &address_space_memory); > > QLIST_INSERT_HEAD(&vhost_devices, hdev, entry); > > > > - if (used_memslots > hdev->vhost_ops- > >vhost_backend_memslots_limit(hdev)) { > > + if (!hdev->vhost_ops->vhost_backend_has_free_memslots(hdev)) { > > error_report("vhost backend memory slots limit is less" > > " than current number of present memory slots"); > > r = -1; > > diff --git a/include/hw/virtio/vhost-backend.h > > b/include/hw/virtio/vhost-backend.h > > index 592254f..2eac224 100644 > > --- a/include/hw/virtio/vhost-backend.h > > +++ b/include/hw/virtio/vhost-backend.h > > @@ -36,7 +36,7 @@ struct vhost_iotlb_msg; > > > > typedef int (*vhost_backend_init)(struct vhost_dev *dev, void > > *opaque); typedef int (*vhost_backend_cleanup)(struct vhost_dev > > *dev); -typedef int (*vhost_backend_memslots_limit)(struct vhost_dev > > *dev); > > +typedef bool (*vhost_backend_has_free_memslots)(struct vhost_dev > > +*dev); > > > > typedef int (*vhost_net_set_backend_op)(struct vhost_dev *dev, > > struct vhost_vring_file *file); @@ > > -94,12 +94,13 @@ typedef int (*vhost_set_config_op)(struct vhost_dev *dev, > const uint8_t *data, > > uint32_t flags); typedef int > > (*vhost_get_config_op)(struct vhost_dev *dev, uint8_t *config, > > uint32_t config_len); > > +typedef void (*vhost_set_used_memslots_op)(struct vhost_dev *dev); > > > > typedef struct VhostOps { > > VhostBackendType backend_type; > > vhost_backend_init vhost_backend_init; > > vhost_backend_cleanup vhost_backend_cleanup; > > - vhost_backend_memslots_limit vhost_backend_memslots_limit; > > + vhost_backend_has_free_memslots vhost_backend_has_free_memslots; > > vhost_net_set_backend_op vhost_net_set_backend; > > vhost_net_set_mtu_op vhost_net_set_mtu; > > vhost_scsi_set_endpoint_op vhost_scsi_set_endpoint; @@ -130,6 > > +131,7 @@ typedef struct VhostOps { > > vhost_send_device_iotlb_msg_op vhost_send_device_iotlb_msg; > > vhost_get_config_op vhost_get_config; > > vhost_set_config_op vhost_set_config; > > + vhost_set_used_memslots_op vhost_set_used_memslots; > > } VhostOps; > > > > extern const VhostOps user_ops; > > -- > > 1.8.3.1 > >