On Mon, Oct 15, 2012 at 3:48 PM, Dave Chinner <[email protected]> wrote: > On Wed, Oct 10, 2012 at 06:07:33PM +0800, [email protected] wrote: >> From: Zhi Yong Wu <[email protected]> >> >> FS_IOC_GET_HEAT_INFO: return a struct containing the various >> metrics collected in btrfs_freq_data structs, and also return a >> calculated data temperature based on those metrics. Optionally, retrieve >> the temperature from the hot data hash list instead of recalculating it. >> >> FS_IOC_GET_HEAT_OPTS: return an integer representing the current >> state of hot data tracking and migration: >> >> 0 = do nothing >> 1 = track frequency of access >> >> FS_IOC_SET_HEAT_OPTS: change the state of hot data tracking and >> migration, as described above. > ..... >> +struct hot_heat_info { >> + __u64 avg_delta_reads; >> + __u64 avg_delta_writes; >> + __u64 last_read_time; >> + __u64 last_write_time; >> + __u32 num_reads; >> + __u32 num_writes; >> + __u32 temperature; >> + __u8 live; >> + char filename[PATH_MAX]; > > Don't put the filename in the ioctl and open the file in the kernel. > Have userspace open the file directly and issue the ioctl on the fd > that is returned. OK, thanks. By the way, do you think that it is necessary to provide another new ioctl interface to set the temperature value? > > Cheers, > > Dave. > -- > Dave Chinner > [email protected]
-- Regards, Zhi Yong Wu -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
