On 1/8/2020 9:55 AM, David Marchand wrote: > On Wed, Jan 8, 2020 at 10:09 AM Ferruh Yigit <ferruh.yi...@intel.com> wrote: >> >> On 1/8/2020 8:56 AM, David Marchand wrote: >>> Hello Laurent, >>> >>> Bonne année. >>> >>> Cc: maintainers. >>> >>> On Tue, Jan 7, 2020 at 3:57 PM Laurent Hardy <laurent.ha...@6wind.com> >>> wrote: >>>> >>>> In current led control API we have no way to know if a device is able >>>> to handle on/off requests coming from the application. >>>> Knowing if the device is led control capable could be useful to avoid >>>> exchanges between application and kernel. >>>> Using the on/off requests to flag if the device is led control capable >>>> (based on the ENOSUP returned error) is not convenient as such request >>>> can change the led state on device. >>>> >>>> This patch adds a new function rte_eth_led_ctrl_capable() that will look >>>> for led_off/on dev ops availability on the related pmd, to know if the >>>> device is able to handle such led control requests (on/off). >>> >>> This patch breaks the ABI, which is BAD :-). >> >> Why it is an ABI break, dev_ops should be between library and drivers, so it >> should be out of the ABI concern, isn't it. > > You are right. > So in our context, this is not an ABI breakage. > But abidiff still reports it, so maybe some filtering is required to > avoid this false positive. > > Note that if we insert an ops before rx_queue_count, we would have a > real ABI breakage, as this ops is accessed via an inline wrapper by > applications. >
This is good point, perhaps we should add a comment to that line to highlight it. > >> >>> This new api only needs to look at the existing ops, so you can remove >>> the (unused in your patch) dev_led_ctrl_capable ops. >>> >>> OTOH, would it make sense to expose this capability in dev_flags? >>> >> >> 'rte_eth_led_on()' & 'rte_eth_led_off()' APIs returns '-ENOTSUP' when the not >> supported, can that help application to understand? > > You might want to know it is supported without changing the state. > Laurent? > > > > -- > David Marchand >
