* [dpdk-dev] [PATCH v2 0/3] vhost: make virtqueue cache-friendly @ 2021-03-16 12:41 Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 1/3] vhost: remove unused Vhost virtqueue field Maxime Coquelin ` (2 more replies) 0 siblings, 3 replies; 8+ messages in thread From: Maxime Coquelin @ 2021-03-16 12:41 UTC (permalink / raw) To: dev, chenbo.xia, amorenoz, david.marchand, olivier.matz, bnemeth Cc: Maxime Coquelin As done for Virtio PMD, this series improves cache utilization of the vhost_virtqueue struct by removing unused field, make the live-migration cache dynamically allocated at live-migration setup time and by moving fields around so that hot fields are on the first cachelines. With this series, The struct vhost_virtqueue size goes from 832B (13 cachelines) down to 320B (5 cachelines). With this series and the virtio one, I measure a gain of up to 8% in IO loop micro-benchmark with packed ring, and 5% with split ring. I don't have a setup at hand to run PVP testing, but it might be interresting to get the numbers as I suspect the cache pressure is higher in this test as in real use-cases. Changes in v2: ============== - Add log_cache freeing in free_vq (Chenbo) Maxime Coquelin (3): vhost: remove unused Vhost virtqueue field vhost: move dirty logging cache out of the virtqueue vhost: optimize vhost virtqueue struct lib/librte_vhost/vhost.c | 16 +++++++++-- lib/librte_vhost/vhost.h | 54 +++++++++++++++++------------------ lib/librte_vhost/vhost_user.c | 25 ++++++++++++++++ 3 files changed, 66 insertions(+), 29 deletions(-) -- 2.29.2 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [dpdk-dev] [PATCH v2 1/3] vhost: remove unused Vhost virtqueue field 2021-03-16 12:41 [dpdk-dev] [PATCH v2 0/3] vhost: make virtqueue cache-friendly Maxime Coquelin @ 2021-03-16 12:41 ` Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct Maxime Coquelin 2 siblings, 0 replies; 8+ messages in thread From: Maxime Coquelin @ 2021-03-16 12:41 UTC (permalink / raw) To: dev, chenbo.xia, amorenoz, david.marchand, olivier.matz, bnemeth Cc: Maxime Coquelin This patch removes the "backend" field of the vhost_virtqueue struct, which is not used by the library. Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> Reviewed-by: Chenbo Xia <chenbo.xia@intel.com> --- lib/librte_vhost/vhost.c | 2 -- lib/librte_vhost/vhost.h | 2 -- 2 files changed, 4 deletions(-) diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c index 52ab93d1ec..5a7c0c6cff 100644 --- a/lib/librte_vhost/vhost.c +++ b/lib/librte_vhost/vhost.c @@ -558,8 +558,6 @@ init_vring_queue(struct virtio_net *dev, uint32_t vring_idx) vq->notif_enable = VIRTIO_UNINITIALIZED_NOTIF; vhost_user_iotlb_init(dev, vring_idx); - /* Backends are set to -1 indicating an inactive device. */ - vq->backend = -1; } static void diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 658f6fc287..717f410548 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -143,8 +143,6 @@ struct vhost_virtqueue { #define VIRTIO_INVALID_EVENTFD (-1) #define VIRTIO_UNINITIALIZED_EVENTFD (-2) - /* Backend value to determine if device should started/stopped */ - int backend; int enabled; int access_ok; int ready; -- 2.29.2 ^ permalink raw reply [flat|nested] 8+ messages in thread
* [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue 2021-03-16 12:41 [dpdk-dev] [PATCH v2 0/3] vhost: make virtqueue cache-friendly Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 1/3] vhost: remove unused Vhost virtqueue field Maxime Coquelin @ 2021-03-16 12:41 ` Maxime Coquelin 2021-03-16 13:13 ` David Marchand 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct Maxime Coquelin 2 siblings, 1 reply; 8+ messages in thread From: Maxime Coquelin @ 2021-03-16 12:41 UTC (permalink / raw) To: dev, chenbo.xia, amorenoz, david.marchand, olivier.matz, bnemeth Cc: Maxime Coquelin This patch moves the per-virtqueue's dirty logging cache out of the virtqueue struct, by allocating it dynamically only when live-migration is enabled. It saves 8 cachelines in vhost_virtqueue struct. Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> --- lib/librte_vhost/vhost.c | 14 ++++++++++++++ lib/librte_vhost/vhost.h | 2 +- lib/librte_vhost/vhost_user.c | 25 +++++++++++++++++++++++++ 3 files changed, 40 insertions(+), 1 deletion(-) diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c index 5a7c0c6cff..c3490ce897 100644 --- a/lib/librte_vhost/vhost.c +++ b/lib/librte_vhost/vhost.c @@ -145,6 +145,10 @@ __vhost_log_cache_sync(struct virtio_net *dev, struct vhost_virtqueue *vq) if (unlikely(!dev->log_base)) return; + /* No cache, nothing to sync */ + if (unlikely(!vq->log_cache)) + return; + rte_atomic_thread_fence(__ATOMIC_RELEASE); log_base = (unsigned long *)(uintptr_t)dev->log_base; @@ -177,6 +181,14 @@ vhost_log_cache_page(struct virtio_net *dev, struct vhost_virtqueue *vq, uint32_t offset = page / (sizeof(unsigned long) << 3); int i; + if (unlikely(!vq->log_cache)) { + /* No logging cache allocated, write dirty log map directly */ + rte_smp_wmb(); + vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page); + + return; + } + for (i = 0; i < vq->log_cache_nb_elem; i++) { struct log_cache_entry *elem = vq->log_cache + i; @@ -354,6 +366,8 @@ free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq) } rte_free(vq->batch_copy_elems); rte_mempool_free(vq->iotlb_pool); + if (vq->log_cache) + rte_free(vq->log_cache); rte_free(vq); } diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 717f410548..3a71dfeed9 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -183,7 +183,7 @@ struct vhost_virtqueue { bool used_wrap_counter; bool avail_wrap_counter; - struct log_cache_entry log_cache[VHOST_LOG_CACHE_NR]; + struct log_cache_entry *log_cache; uint16_t log_cache_nb_elem; rte_rwlock_t iotlb_lock; diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c index a60bb945ad..0f452d6ff3 100644 --- a/lib/librte_vhost/vhost_user.c +++ b/lib/librte_vhost/vhost_user.c @@ -2022,6 +2022,11 @@ vhost_user_get_vring_base(struct virtio_net **pdev, rte_free(vq->batch_copy_elems); vq->batch_copy_elems = NULL; + if (vq->log_cache) { + rte_free(vq->log_cache); + vq->log_cache = NULL; + } + msg->size = sizeof(msg->payload.state); msg->fd_num = 0; @@ -2121,6 +2126,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg, int fd = msg->fds[0]; uint64_t size, off; void *addr; + uint32_t i; if (validate_msg_fds(msg, 1) != 0) return RTE_VHOST_MSG_RESULT_ERR; @@ -2174,6 +2180,25 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg, dev->log_base = dev->log_addr + off; dev->log_size = size; + for (i = 0; i < dev->nr_vring; i++) { + struct vhost_virtqueue *vq = dev->virtqueue[i]; + + if (vq->log_cache) { + rte_free(vq->log_cache); + vq->log_cache = NULL; + } + vq->log_cache_nb_elem = 0; + vq->log_cache = rte_zmalloc("vq log cache", + sizeof(struct log_cache_entry) * VHOST_LOG_CACHE_NR, + 0); + /* + * If log cache alloc fail, don't fail migration, but no + * caching will be done, which will impact performance + */ + if (!vq->log_cache) + VHOST_LOG_CONFIG(ERR, "Failed to allocate VQ logging cache\n"); + } + /* * The spec is not clear about it (yet), but QEMU doesn't expect * any payload in the reply. -- 2.29.2 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue Maxime Coquelin @ 2021-03-16 13:13 ` David Marchand 2021-03-17 10:20 ` Maxime Coquelin 0 siblings, 1 reply; 8+ messages in thread From: David Marchand @ 2021-03-16 13:13 UTC (permalink / raw) To: Maxime Coquelin Cc: dev, Xia, Chenbo, Adrian Moreno Zapata, Olivier Matz, bnemeth On Tue, Mar 16, 2021 at 1:42 PM Maxime Coquelin <maxime.coquelin@redhat.com> wrote: > > This patch moves the per-virtqueue's dirty logging cache > out of the virtqueue struct, by allocating it dynamically > only when live-migration is enabled. > > It saves 8 cachelines in vhost_virtqueue struct. > > Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> > --- > lib/librte_vhost/vhost.c | 14 ++++++++++++++ > lib/librte_vhost/vhost.h | 2 +- > lib/librte_vhost/vhost_user.c | 25 +++++++++++++++++++++++++ > 3 files changed, 40 insertions(+), 1 deletion(-) > > diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c > index 5a7c0c6cff..c3490ce897 100644 > --- a/lib/librte_vhost/vhost.c > +++ b/lib/librte_vhost/vhost.c > @@ -145,6 +145,10 @@ __vhost_log_cache_sync(struct virtio_net *dev, struct vhost_virtqueue *vq) > if (unlikely(!dev->log_base)) > return; > > + /* No cache, nothing to sync */ > + if (unlikely(!vq->log_cache)) > + return; > + > rte_atomic_thread_fence(__ATOMIC_RELEASE); > > log_base = (unsigned long *)(uintptr_t)dev->log_base; > @@ -177,6 +181,14 @@ vhost_log_cache_page(struct virtio_net *dev, struct vhost_virtqueue *vq, > uint32_t offset = page / (sizeof(unsigned long) << 3); > int i; > > + if (unlikely(!vq->log_cache)) { > + /* No logging cache allocated, write dirty log map directly */ > + rte_smp_wmb(); We try not to reintroduce full barriers (checkpatch caught this). > + vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page); > + > + return; > + } > + > for (i = 0; i < vq->log_cache_nb_elem; i++) { > struct log_cache_entry *elem = vq->log_cache + i; > > @@ -354,6 +366,8 @@ free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq) > } > rte_free(vq->batch_copy_elems); > rte_mempool_free(vq->iotlb_pool); > + if (vq->log_cache) > + rte_free(vq->log_cache); No if() needed. > rte_free(vq); > } > > diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h > index 717f410548..3a71dfeed9 100644 > --- a/lib/librte_vhost/vhost.h > +++ b/lib/librte_vhost/vhost.h > @@ -183,7 +183,7 @@ struct vhost_virtqueue { > bool used_wrap_counter; > bool avail_wrap_counter; > > - struct log_cache_entry log_cache[VHOST_LOG_CACHE_NR]; > + struct log_cache_entry *log_cache; > uint16_t log_cache_nb_elem; > > rte_rwlock_t iotlb_lock; > diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c > index a60bb945ad..0f452d6ff3 100644 > --- a/lib/librte_vhost/vhost_user.c > +++ b/lib/librte_vhost/vhost_user.c > @@ -2022,6 +2022,11 @@ vhost_user_get_vring_base(struct virtio_net **pdev, > rte_free(vq->batch_copy_elems); > vq->batch_copy_elems = NULL; > > + if (vq->log_cache) { > + rte_free(vq->log_cache); > + vq->log_cache = NULL; > + } Idem. > + > msg->size = sizeof(msg->payload.state); > msg->fd_num = 0; > > @@ -2121,6 +2126,7 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg, > int fd = msg->fds[0]; > uint64_t size, off; > void *addr; > + uint32_t i; > > if (validate_msg_fds(msg, 1) != 0) > return RTE_VHOST_MSG_RESULT_ERR; > @@ -2174,6 +2180,25 @@ vhost_user_set_log_base(struct virtio_net **pdev, struct VhostUserMsg *msg, > dev->log_base = dev->log_addr + off; > dev->log_size = size; > > + for (i = 0; i < dev->nr_vring; i++) { > + struct vhost_virtqueue *vq = dev->virtqueue[i]; > + > + if (vq->log_cache) { > + rte_free(vq->log_cache); > + vq->log_cache = NULL; > + } Idem. > + vq->log_cache_nb_elem = 0; > + vq->log_cache = rte_zmalloc("vq log cache", > + sizeof(struct log_cache_entry) * VHOST_LOG_CACHE_NR, > + 0); > + /* > + * If log cache alloc fail, don't fail migration, but no > + * caching will be done, which will impact performance > + */ > + if (!vq->log_cache) > + VHOST_LOG_CONFIG(ERR, "Failed to allocate VQ logging cache\n"); > + } > + > /* > * The spec is not clear about it (yet), but QEMU doesn't expect > * any payload in the reply. > -- > 2.29.2 > -- David Marchand ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue 2021-03-16 13:13 ` David Marchand @ 2021-03-17 10:20 ` Maxime Coquelin 0 siblings, 0 replies; 8+ messages in thread From: Maxime Coquelin @ 2021-03-17 10:20 UTC (permalink / raw) To: David Marchand Cc: dev, Xia, Chenbo, Adrian Moreno Zapata, Olivier Matz, bnemeth On 3/16/21 2:13 PM, David Marchand wrote: > On Tue, Mar 16, 2021 at 1:42 PM Maxime Coquelin > <maxime.coquelin@redhat.com> wrote: >> >> This patch moves the per-virtqueue's dirty logging cache >> out of the virtqueue struct, by allocating it dynamically >> only when live-migration is enabled. >> >> It saves 8 cachelines in vhost_virtqueue struct. >> >> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> >> --- >> lib/librte_vhost/vhost.c | 14 ++++++++++++++ >> lib/librte_vhost/vhost.h | 2 +- >> lib/librte_vhost/vhost_user.c | 25 +++++++++++++++++++++++++ >> 3 files changed, 40 insertions(+), 1 deletion(-) >> >> diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c >> index 5a7c0c6cff..c3490ce897 100644 >> --- a/lib/librte_vhost/vhost.c >> +++ b/lib/librte_vhost/vhost.c >> @@ -145,6 +145,10 @@ __vhost_log_cache_sync(struct virtio_net *dev, struct vhost_virtqueue *vq) >> if (unlikely(!dev->log_base)) >> return; >> >> + /* No cache, nothing to sync */ >> + if (unlikely(!vq->log_cache)) >> + return; >> + >> rte_atomic_thread_fence(__ATOMIC_RELEASE); >> >> log_base = (unsigned long *)(uintptr_t)dev->log_base; >> @@ -177,6 +181,14 @@ vhost_log_cache_page(struct virtio_net *dev, struct vhost_virtqueue *vq, >> uint32_t offset = page / (sizeof(unsigned long) << 3); >> int i; >> >> + if (unlikely(!vq->log_cache)) { >> + /* No logging cache allocated, write dirty log map directly */ >> + rte_smp_wmb(); > > We try not to reintroduce full barriers (checkpatch caught this). Agree, the rebase introduced it again silently. > >> + vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page); >> + >> + return; >> + } >> + >> for (i = 0; i < vq->log_cache_nb_elem; i++) { >> struct log_cache_entry *elem = vq->log_cache + i; >> >> @@ -354,6 +366,8 @@ free_vq(struct virtio_net *dev, struct vhost_virtqueue *vq) >> } >> rte_free(vq->batch_copy_elems); >> rte_mempool_free(vq->iotlb_pool); >> + if (vq->log_cache) >> + rte_free(vq->log_cache); > > No if() needed. Yes, will fix in next revision. > >> rte_free(vq); >> } >> >> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h >> index 717f410548..3a71dfeed9 100644 >> --- a/lib/librte_vhost/vhost.h >> +++ b/lib/librte_vhost/vhost.h >> @@ -183,7 +183,7 @@ struct vhost_virtqueue { >> bool used_wrap_counter; >> bool avail_wrap_counter; >> >> - struct log_cache_entry log_cache[VHOST_LOG_CACHE_NR]; >> + struct log_cache_entry *log_cache; >> uint16_t log_cache_nb_elem; >> >> rte_rwlock_t iotlb_lock; >> diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c >> index a60bb945ad..0f452d6ff3 100644 >> --- a/lib/librte_vhost/vhost_user.c >> +++ b/lib/librte_vhost/vhost_user.c >> @@ -2022,6 +2022,11 @@ vhost_user_get_vring_base(struct virtio_net **pdev, >> rte_free(vq->batch_copy_elems); >> vq->batch_copy_elems = NULL; >> >> + if (vq->log_cache) { >> + rte_free(vq->log_cache); >> + vq->log_cache = NULL; >> + } > > Idem. > > Thanks, Maxime ^ permalink raw reply [flat|nested] 8+ messages in thread
* [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct 2021-03-16 12:41 [dpdk-dev] [PATCH v2 0/3] vhost: make virtqueue cache-friendly Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 1/3] vhost: remove unused Vhost virtqueue field Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue Maxime Coquelin @ 2021-03-16 12:41 ` Maxime Coquelin 2021-03-16 13:38 ` David Marchand 2 siblings, 1 reply; 8+ messages in thread From: Maxime Coquelin @ 2021-03-16 12:41 UTC (permalink / raw) To: dev, chenbo.xia, amorenoz, david.marchand, olivier.matz, bnemeth Cc: Maxime Coquelin This patch moves vhost_virtuqueue struct fields in order to both optimize packing and move hot fields on the first cachelines. Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> --- lib/librte_vhost/vhost.h | 52 +++++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 25 deletions(-) diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h index 3a71dfeed9..ae45b05dd1 100644 --- a/lib/librte_vhost/vhost.h +++ b/lib/librte_vhost/vhost.h @@ -133,7 +133,7 @@ struct vhost_virtqueue { struct vring_used *used; struct vring_packed_desc_event *device_event; }; - uint32_t size; + uint16_t size; uint16_t last_avail_idx; uint16_t last_used_idx; @@ -143,29 +143,12 @@ struct vhost_virtqueue { #define VIRTIO_INVALID_EVENTFD (-1) #define VIRTIO_UNINITIALIZED_EVENTFD (-2) - int enabled; - int access_ok; - int ready; - int notif_enable; -#define VIRTIO_UNINITIALIZED_NOTIF (-1) + bool enabled; + bool access_ok; + bool ready; rte_spinlock_t access_lock; - /* Used to notify the guest (trigger interrupt) */ - int callfd; - /* Currently unused as polling mode is enabled */ - int kickfd; - - /* Physical address of used ring, for logging */ - uint64_t log_guest_addr; - - /* inflight share memory info */ - union { - struct rte_vhost_inflight_info_split *inflight_split; - struct rte_vhost_inflight_info_packed *inflight_packed; - }; - struct rte_vhost_resubmit_info *resubmit_inflight; - uint64_t global_counter; union { struct vring_used_elem *shadow_used_split; @@ -176,22 +159,36 @@ struct vhost_virtqueue { uint16_t shadow_aligned_idx; /* Record packed ring first dequeue desc index */ uint16_t shadow_last_used_idx; - struct vhost_vring_addr ring_addrs; - struct batch_copy_elem *batch_copy_elems; uint16_t batch_copy_nb_elems; + struct batch_copy_elem *batch_copy_elems; bool used_wrap_counter; bool avail_wrap_counter; - struct log_cache_entry *log_cache; + /* Physical address of used ring, for logging */ uint16_t log_cache_nb_elem; + uint64_t log_guest_addr; + struct log_cache_entry *log_cache; rte_rwlock_t iotlb_lock; rte_rwlock_t iotlb_pending_lock; struct rte_mempool *iotlb_pool; TAILQ_HEAD(, vhost_iotlb_entry) iotlb_list; - int iotlb_cache_nr; TAILQ_HEAD(, vhost_iotlb_entry) iotlb_pending_list; + int iotlb_cache_nr; + + /* Used to notify the guest (trigger interrupt) */ + int callfd; + /* Currently unused as polling mode is enabled */ + int kickfd; + + /* inflight share memory info */ + union { + struct rte_vhost_inflight_info_split *inflight_split; + struct rte_vhost_inflight_info_packed *inflight_packed; + }; + struct rte_vhost_resubmit_info *resubmit_inflight; + uint64_t global_counter; /* operation callbacks for async dma */ struct rte_vhost_async_channel_ops async_ops; @@ -212,6 +209,11 @@ struct vhost_virtqueue { bool async_inorder; bool async_registered; uint16_t async_threshold; + + int notif_enable; +#define VIRTIO_UNINITIALIZED_NOTIF (-1) + + struct vhost_vring_addr ring_addrs; } __rte_cache_aligned; /* Virtio device status as per Virtio specification */ -- 2.29.2 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct Maxime Coquelin @ 2021-03-16 13:38 ` David Marchand 2021-03-17 10:26 ` Maxime Coquelin 0 siblings, 1 reply; 8+ messages in thread From: David Marchand @ 2021-03-16 13:38 UTC (permalink / raw) To: Maxime Coquelin Cc: dev, Xia, Chenbo, Adrian Moreno Zapata, Olivier Matz, bnemeth On Tue, Mar 16, 2021 at 1:42 PM Maxime Coquelin <maxime.coquelin@redhat.com> wrote: > > This patch moves vhost_virtuqueue struct fields in order virtqueue You might want to add something in your local dictionary :-p. > to both optimize packing and move hot fields on the first > cachelines. > > Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> > --- > lib/librte_vhost/vhost.h | 52 +++++++++++++++++++++------------------- > 1 file changed, 27 insertions(+), 25 deletions(-) > > diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h > index 3a71dfeed9..ae45b05dd1 100644 > --- a/lib/librte_vhost/vhost.h > +++ b/lib/librte_vhost/vhost.h > @@ -133,7 +133,7 @@ struct vhost_virtqueue { > struct vring_used *used; > struct vring_packed_desc_event *device_event; > }; > - uint32_t size; > + uint16_t size; There is one site in the code that could be problematic: vhost_user_set_vring_num() ... vq->size = msg->payload.state.num; ... if (vq->size > 32768) { payload.state.num is an unsigned int, so we'd better check its value as an unsigned int, before storing to vq->size. > > uint16_t last_avail_idx; > uint16_t last_used_idx; > @@ -143,29 +143,12 @@ struct vhost_virtqueue { > #define VIRTIO_INVALID_EVENTFD (-1) > #define VIRTIO_UNINITIALIZED_EVENTFD (-2) > > - int enabled; > - int access_ok; > - int ready; > - int notif_enable; > -#define VIRTIO_UNINITIALIZED_NOTIF (-1) > + bool enabled; > + bool access_ok; > + bool ready; Changing those types is fine, but it is a bit odd to still see boolean_var = 0 or boolean_var = 1 in the rest of the code. > > rte_spinlock_t access_lock; > > - /* Used to notify the guest (trigger interrupt) */ > - int callfd; > - /* Currently unused as polling mode is enabled */ > - int kickfd; > - > - /* Physical address of used ring, for logging */ > - uint64_t log_guest_addr; > - > - /* inflight share memory info */ > - union { > - struct rte_vhost_inflight_info_split *inflight_split; > - struct rte_vhost_inflight_info_packed *inflight_packed; > - }; > - struct rte_vhost_resubmit_info *resubmit_inflight; > - uint64_t global_counter; > > union { > struct vring_used_elem *shadow_used_split; > @@ -176,22 +159,36 @@ struct vhost_virtqueue { > uint16_t shadow_aligned_idx; > /* Record packed ring first dequeue desc index */ > uint16_t shadow_last_used_idx; > - struct vhost_vring_addr ring_addrs; > > - struct batch_copy_elem *batch_copy_elems; > uint16_t batch_copy_nb_elems; > + struct batch_copy_elem *batch_copy_elems; > bool used_wrap_counter; > bool avail_wrap_counter; > > - struct log_cache_entry *log_cache; > + /* Physical address of used ring, for logging */ > uint16_t log_cache_nb_elem; Indent is broken / not consistent, probably because you cut/pasted lines. > + uint64_t log_guest_addr; > + struct log_cache_entry *log_cache; > > rte_rwlock_t iotlb_lock; > rte_rwlock_t iotlb_pending_lock; > struct rte_mempool *iotlb_pool; > TAILQ_HEAD(, vhost_iotlb_entry) iotlb_list; > - int iotlb_cache_nr; > TAILQ_HEAD(, vhost_iotlb_entry) iotlb_pending_list; > + int iotlb_cache_nr; > + > + /* Used to notify the guest (trigger interrupt) */ > + int callfd; > + /* Currently unused as polling mode is enabled */ > + int kickfd; > + > + /* inflight share memory info */ > + union { > + struct rte_vhost_inflight_info_split *inflight_split; > + struct rte_vhost_inflight_info_packed *inflight_packed; > + }; > + struct rte_vhost_resubmit_info *resubmit_inflight; > + uint64_t global_counter; > > /* operation callbacks for async dma */ > struct rte_vhost_async_channel_ops async_ops; > @@ -212,6 +209,11 @@ struct vhost_virtqueue { > bool async_inorder; > bool async_registered; > uint16_t async_threshold; > + > + int notif_enable; > +#define VIRTIO_UNINITIALIZED_NOTIF (-1) > + > + struct vhost_vring_addr ring_addrs; > } __rte_cache_aligned; > > /* Virtio device status as per Virtio specification */ > -- > 2.29.2 > -- David Marchand ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct 2021-03-16 13:38 ` David Marchand @ 2021-03-17 10:26 ` Maxime Coquelin 0 siblings, 0 replies; 8+ messages in thread From: Maxime Coquelin @ 2021-03-17 10:26 UTC (permalink / raw) To: David Marchand Cc: dev, Xia, Chenbo, Adrian Moreno Zapata, Olivier Matz, bnemeth On 3/16/21 2:38 PM, David Marchand wrote: > On Tue, Mar 16, 2021 at 1:42 PM Maxime Coquelin > <maxime.coquelin@redhat.com> wrote: >> >> This patch moves vhost_virtuqueue struct fields in order > > virtqueue > You might want to add something in your local dictionary :-p. > > >> to both optimize packing and move hot fields on the first >> cachelines. >> >> Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com> >> --- >> lib/librte_vhost/vhost.h | 52 +++++++++++++++++++++------------------- >> 1 file changed, 27 insertions(+), 25 deletions(-) >> >> diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h >> index 3a71dfeed9..ae45b05dd1 100644 >> --- a/lib/librte_vhost/vhost.h >> +++ b/lib/librte_vhost/vhost.h >> @@ -133,7 +133,7 @@ struct vhost_virtqueue { >> struct vring_used *used; >> struct vring_packed_desc_event *device_event; >> }; >> - uint32_t size; >> + uint16_t size; > > There is one site in the code that could be problematic: > > vhost_user_set_vring_num() > ... > vq->size = msg->payload.state.num; > ... > if (vq->size > 32768) { > > payload.state.num is an unsigned int, so we'd better check its value > as an unsigned int, before storing to vq->size. Indeed, I will rework the function, so that it checks that msg->payload.state.num is smaller than 32K to comply with the spec, and so remove the later check on vq->size. > >> >> uint16_t last_avail_idx; >> uint16_t last_used_idx; >> @@ -143,29 +143,12 @@ struct vhost_virtqueue { >> #define VIRTIO_INVALID_EVENTFD (-1) >> #define VIRTIO_UNINITIALIZED_EVENTFD (-2) >> >> - int enabled; >> - int access_ok; >> - int ready; >> - int notif_enable; >> -#define VIRTIO_UNINITIALIZED_NOTIF (-1) >> + bool enabled; >> + bool access_ok; >> + bool ready; > > Changing those types is fine, but it is a bit odd to still see > boolean_var = 0 or boolean_var = 1 in the rest of the code. Yes, I fix all the places with assigning boolean values. > >> >> rte_spinlock_t access_lock; >> >> - /* Used to notify the guest (trigger interrupt) */ >> - int callfd; >> - /* Currently unused as polling mode is enabled */ >> - int kickfd; >> - >> - /* Physical address of used ring, for logging */ >> - uint64_t log_guest_addr; >> - >> - /* inflight share memory info */ >> - union { >> - struct rte_vhost_inflight_info_split *inflight_split; >> - struct rte_vhost_inflight_info_packed *inflight_packed; >> - }; >> - struct rte_vhost_resubmit_info *resubmit_inflight; >> - uint64_t global_counter; >> >> union { >> struct vring_used_elem *shadow_used_split; >> @@ -176,22 +159,36 @@ struct vhost_virtqueue { >> uint16_t shadow_aligned_idx; >> /* Record packed ring first dequeue desc index */ >> uint16_t shadow_last_used_idx; >> - struct vhost_vring_addr ring_addrs; >> >> - struct batch_copy_elem *batch_copy_elems; >> uint16_t batch_copy_nb_elems; >> + struct batch_copy_elem *batch_copy_elems; >> bool used_wrap_counter; >> bool avail_wrap_counter; >> >> - struct log_cache_entry *log_cache; >> + /* Physical address of used ring, for logging */ >> uint16_t log_cache_nb_elem; > > Indent is broken / not consistent, probably because you cut/pasted lines. Will fix it. Thanks, Maxime ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-03-17 10:27 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-03-16 12:41 [dpdk-dev] [PATCH v2 0/3] vhost: make virtqueue cache-friendly Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 1/3] vhost: remove unused Vhost virtqueue field Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 2/3] vhost: move dirty logging cache out of the virtqueue Maxime Coquelin 2021-03-16 13:13 ` David Marchand 2021-03-17 10:20 ` Maxime Coquelin 2021-03-16 12:41 ` [dpdk-dev] [PATCH v2 3/3] vhost: optimize vhost virtqueue struct Maxime Coquelin 2021-03-16 13:38 ` David Marchand 2021-03-17 10:26 ` Maxime Coquelin
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for NNTP newsgroup(s).