09.01.2020 10:24, Sameer Pujar пишет: > > On 1/9/2020 11:30 AM, Dmitry Osipenko wrote: >> External email: Use caution opening links or attachments >> >> >> 09.01.2020 08:09, Sameer Pujar пишет: >>> This patch adds a macro 'regmap_read_poll_timeout_atomic' that works >>> similar to 'readx_poll_timeout_atomic' defined in linux/iopoll.h; This >>> is atomic version of already available 'regmap_read_poll_timeout' macro. >>> >>> It should be noted that above atomic macro cannot be used by all >>> regmaps. >>> If the regmap is set up for atomic use (flat or no cache and MMIO) then >>> only it can use. >>> >>> Signed-off-by: Sameer Pujar <spujar@xxxxxxxxxx> >>> --- >> Could you please explain what is the targeted use-case here? > > I was trying to use regmap_read_poll_timeout() to poll for status change > of a register. This resulted in "BUG: scheduling while atomic". The > callback function, in which I was trying to use the macro, runs in > atomic context. Hence new atomic macro is added. I was checking ALSA > playback/capture and trigger() callback had to monitor some register > status. > > In general, the new macro can be used in atomic callbacks where regmap > interface is used and polling is required. > You should send a full patchset because it may turn out that the patch which makes use of the new feature isn't correct or maybe the new feature isn't really needed. If there was a previous discussion about the need for this change, then you should provide a link to that discussion. Please note that usually changes without a real use-case in kernel are not getting picked up or they are getting removed later on if nobody makes use of them, so I assume this is a kind of an RFC patch for now.
