2018-01-19 10:41 GMT+08:00 Martin K. Petersen <martin.petersen@xxxxxxxxxx>: > > Hi Weiping, > >> Add user friendly command strings sd_wce_rcd to enable/disable >> write&read cache. User can enable both write and read cache by one of >> the following commands: > > I am not entirely sure what the rationale is behind your patch. Is there > some deficiency in the existing cache control interface that you are > trying to address? Or is the problem simply that it is poorly > documented? Hi Marin, currently, there are four combinations as following: "write through", "none", "write back", "write back, no read (daft)" cache_type can control both write and read cache, but for "write through" and "write back" we can not know clearly how to control the read cache. I prefer use words like"w0r1", "w0r0", "w1r1", "w1r0", that "1" means enable, "0" means disable. The user know clearly what they are doing when typing these short words. Hi James, > I don't think we can do this. The output of the cache type in sysfs is > a user exported ABI. We'd potentially break it if we add extra stuff. If so, I'll not change the output, only add new match array. > -- > Martin K. Petersen Oracle Linux Engineering
