[dpdk-dev] [PATCH v5 2/5] vhost: implement rte_power_monitor API

[Li, Miao]

Hi Chenbo,

> -----Original Message-----
> From: Xia, Chenbo <chenbo.xia at intel.com>
> Sent: Friday, October 15, 2021 3:38 PM
> To: Li, Miao <miao.li at intel.com>; dev at dpdk.org
> Cc: maxime.coquelin at redhat.com
> Subject: RE: [PATCH v5 2/5] vhost: implement rte_power_monitor API
> 
> Hi,
> 
> > -----Original Message-----
> > From: Li, Miao <miao.li at intel.com>
> > Sent: Friday, October 15, 2021 11:12 PM
> > To: dev at dpdk.org
> > Cc: Xia, Chenbo <chenbo.xia at intel.com>; maxime.coquelin at redhat.com; Li,
> Miao
> > <miao.li at intel.com>
> > Subject: [PATCH v5 2/5] vhost: implement rte_power_monitor API
> >
> > This patch defines rte_vhost_power_monitor_cond which is used to pass
> > some information to vhost driver. The information is including the address
> > to monitor, the expected value, the mask to extract value read from 'addr',
> > the value size of monitor address, the match flag used to distinguish the
> > value used to match something or not match something. Vhost driver can use
> > these information to fill rte_power_monitor_cond.
> >
> > Signed-off-by: Miao Li <miao.li at intel.com>
> > ---
> >  doc/guides/rel_notes/release_21_11.rst |  4 +++
> >  lib/vhost/rte_vhost.h                  | 44 ++++++++++++++++++++++++++
> >  lib/vhost/version.map                  |  3 ++
> >  lib/vhost/vhost.c                      | 38 ++++++++++++++++++++++
> >  4 files changed, 89 insertions(+)
> >
> > diff --git a/doc/guides/rel_notes/release_21_11.rst
> > b/doc/guides/rel_notes/release_21_11.rst
> > index 27dc896703..ad6d256a55 100644
> > --- a/doc/guides/rel_notes/release_21_11.rst
> > +++ b/doc/guides/rel_notes/release_21_11.rst
> > @@ -72,6 +72,10 @@ New Features
> >    Added macros ETH_RSS_IPV4_CHKSUM and ETH_RSS_L4_CHKSUM, now IPv4
> and
> >    TCP/UDP/SCTP header checksum field can be used as input set for RSS.
> >
> > +* **Added power monitor API in vhost library.**
> > +
> > +  Added an API to support power monitor in vhost library.
> > +
> >  * **Updated virtio PMD.**
> >
> >    Implement rte_power_monitor API in virtio PMD.
> > diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
> > index fd372d5259..42bda95e96 100644
> > --- a/lib/vhost/rte_vhost.h
> > +++ b/lib/vhost/rte_vhost.h
> > @@ -292,6 +292,33 @@ struct vhost_device_ops {
> >  	void *reserved[1]; /**< Reserved for future extension */
> >  };
> >
> > +/**
> > + * Power monitor condition.
> > + */
> > +struct rte_vhost_power_monitor_cond {
> > +	/**< Address to monitor for changes */
> > +	volatile void *addr;
> > +	/**< If the `mask` is non-zero, location pointed
> > +	 *   to by `addr` will be read and masked, then
> > +	 *   compared with this value.
> > +	 */
> > +	uint64_t val;
> > +	/**< 64-bit mask to extract value read from `addr` */
> > +	uint64_t mask;
> > +	/**< Data size (in bytes) that will be read from the
> > +	 *   monitored memory location (`addr`). Can be 1, 2,
> > +	 *   4, or 8. Supplying any other value will result in
> > +	 *   an error.
> 
> 'Can be ...' part is not necessary, as this value is defined in vhost
> lib and currently only has two different values for packed or split.

I will remove it in the next version.

> 
> > +	 */
> > +	uint8_t size;
> > +	/**< If 1, and masked value that read from 'addr' equals
> > +	 *   'val', the driver will skip core sleep. If 0, and
> 
> 'will' -> 'should'. As it's a suggestion for vhost driver.
> 
> > +	 *  masked value that read from 'addr' does not equal 'val',
> > +	 *  the driver will skip core sleep.
> 
> Ditto.

I will modify them in the next version.

Thanks,
Miao

> 
> Thanks,
> Chenbo
> 
> > +	 */
> > +	uint8_t match;
> > +};
> > +
> >  /**
> >   * Convert guest physical address to host virtual address
> >   *
> > @@ -903,6 +930,23 @@ int rte_vhost_vring_call(int vid, uint16_t vring_idx);
> >   */
> >  uint32_t rte_vhost_rx_queue_count(int vid, uint16_t qid);
> >
> > +/**
> > + * Get power monitor address of the vhost device
> > + *
> > + * @param vid
> > + *  vhost device ID
> > + * @param queue_id
> > + *  vhost queue ID
> > + * @param pmc
> > + *  power monitor condition
> > + * @return
> > + *  0 on success, -1 on failure
> > + */
> > +__rte_experimental
> > +int
> > +rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
> > +		struct rte_vhost_power_monitor_cond *pmc);
> > +
> >  /**
> >   * Get log base and log size of the vhost device
> >   *
> > diff --git a/lib/vhost/version.map b/lib/vhost/version.map
> > index 8ebde3f694..c8599ddb97 100644
> > --- a/lib/vhost/version.map
> > +++ b/lib/vhost/version.map
> > @@ -85,4 +85,7 @@ EXPERIMENTAL {
> >  	rte_vhost_async_channel_register_thread_unsafe;
> >  	rte_vhost_async_channel_unregister_thread_unsafe;
> >  	rte_vhost_clear_queue_thread_unsafe;
> > +
> > +	# added in 21.11
> > +	rte_vhost_get_monitor_addr;
> >  };
> > diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
> > index 9540522dac..36c896c9e2 100644
> > --- a/lib/vhost/vhost.c
> > +++ b/lib/vhost/vhost.c
> > @@ -1889,5 +1889,43 @@ rte_vhost_async_get_inflight(int vid, uint16_t
> queue_id)
> >  	return ret;
> >  }
> >
> > +int
> > +rte_vhost_get_monitor_addr(int vid, uint16_t queue_id,
> > +		struct rte_vhost_power_monitor_cond *pmc)
> > +{
> > +	struct virtio_net *dev = get_device(vid);
> > +	struct vhost_virtqueue *vq;
> > +
> > +	if (dev == NULL)
> > +		return -1;
> > +	if (queue_id >= VHOST_MAX_VRING)
> > +		return -1;
> > +
> > +	vq = dev->virtqueue[queue_id];
> > +	if (vq == NULL)
> > +		return -1;
> > +
> > +	if (vq_is_packed(dev)) {
> > +		struct vring_packed_desc *desc;
> > +		desc = vq->desc_packed;
> > +		pmc->addr = &desc[vq->last_avail_idx].flags;
> > +		if (vq->avail_wrap_counter)
> > +			pmc->val = VRING_DESC_F_AVAIL;
> > +		else
> > +			pmc->val = VRING_DESC_F_USED;
> > +		pmc->mask = VRING_DESC_F_AVAIL | VRING_DESC_F_USED;
> > +		pmc->size = sizeof(desc[vq->last_avail_idx].flags);
> > +		pmc->match = 1;
> > +	} else {
> > +		pmc->addr = &vq->avail->idx;
> > +		pmc->val = vq->last_avail_idx & (vq->size - 1);
> > +		pmc->mask = vq->size - 1;
> > +		pmc->size = sizeof(vq->avail->idx);
> > +		pmc->match = 0;
> > +	}
> > +
> > +	return 0;
> > +}
> > +
> >  RTE_LOG_REGISTER_SUFFIX(vhost_config_log_level, config, INFO);
> >  RTE_LOG_REGISTER_SUFFIX(vhost_data_log_level, data, WARNING);
> > --
> > 2.25.1