Hi Miao,
> -----Original Message-----
> From: Li, Miao <miao...@intel.com>
> Sent: Friday, September 24, 2021 6:23 PM
> To: dev@dpdk.org
> Cc: Xia, Chenbo <chenbo....@intel.com>; maxime.coque...@redhat.com; Li, Miao
> <miao...@intel.com>
> Subject: [PATCH v3 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...@intel.com>
> ---
> lib/vhost/rte_vhost.h | 41 +++++++++++++++++++++++++++++++++++++++++
> lib/vhost/version.map | 3 +++
> lib/vhost/vhost.c | 38 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 82 insertions(+)
>
> diff --git a/lib/vhost/rte_vhost.h b/lib/vhost/rte_vhost.h
> index 8d875e9322..4e1f2de12f 100644
> --- a/lib/vhost/rte_vhost.h
> +++ b/lib/vhost/rte_vhost.h
> @@ -292,6 +292,30 @@ struct vhost_device_ops {
> void *reserved[1]; /**< Reserved for future extension */
> };
>
> +/**
> + * Power monitor condition.
> + */
> +struct rte_vhost_power_monitor_cond {
> + volatile void *addr; /**< Address to monitor for changes */
> + /**< If the `mask` is non-zero, location pointed
> + * to by `addr` will be read and compared
> + * against this value.
> + */
> + uint64_t val;
Will be read and masked, then compared with this value?
> + uint64_t mask; /**< 64-bit mask to extract value read from `addr` */
> + /**< 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.
> + */
> + uint8_t size;
> + /**< If 1, checking if `val` matches something.
> + * If 0, checking if `val` *doesn't* match a
> + * particular value.
> + */
If 1, and masked value that read from `addr` equals `val`, drivers can exit the
power-saving state.
If 0, ....
The overall comment can't make me understand how this struct is used if I read
the next patch.
> + uint8_t match;
The comment style is a bit messy here. You can make every comment above variable
Definition (like val/size/match ) or make the first line the same as the
variable
line (like addr/mask).
And please update the release note(release_20_11.rst), it's a new feature.
Thanks,
Chenbo
