On 10/09/2017 06:17 PM, David Sterba wrote: > On Sun, Oct 08, 2017 at 10:30:58PM +0200, Hans van Kranenburg wrote: >> Currently struct names for sysfs are generated only based on the >> attribute names. This means that attribute names cannot be reused in >> multiple places throughout the complete btrfs sysfs hierarchy. >> >> E.g. allocation/data/total_bytes and allocation/data/single/total_bytes >> result in the same struct name btrfs_attr_total_bytes. A workaround for >> this case was made in the past by ad hoc creating an extra macro >> wrapper, BTRFS_RAID_ATTR, that inserts some extra text in the struct >> name. >> >> Instead of polluting sysfs.h with such kind of extra macro definitions, >> and only doing so when there are collisions, use a prefix which gets >> inserted in the struct name, so we keep everything nicely grouped >> together by default. >> >> Current collections of attributes are: >> * (the toplevel, empty prefix) >> * allocation >> * space_info >> * raid >> * features >> >> Signed-off-by: Hans van Kranenburg <hans.van.kranenb...@mendix.com> > > Reviewed-by: David Sterba <dste...@suse.com>
Thanks! If anyone wonders why... Last summer I was trying to build in some metadata cow counters per tree, and initially put them in sysfs, then I ran into the fact that I couldn't use the field free_space_tree as a counter because it was also used in the features. It was a nice exercise and the results clearly showed that my suspicions about extent tree rumination problems were right. However, then I discovered tracepoints and could throw away the code again. But I still finished this part, because it makes sysfs nicer for a future developer who wants to change something :D >> @@ -277,7 +277,8 @@ static ssize_t raid_bytes_show(struct kobject *kobj, >> >> down_read(&sinfo->groups_sem); >> list_for_each_entry(block_group, &sinfo->block_groups[index], list) { >> - if (&attr->attr == BTRFS_RAID_ATTR_PTR(total_bytes)) >> + if (&attr->attr == \ > > the \ is not needed here, only in macro defintions that must be on one > logical line Ha, yes... At some point the backslashes were dancing around before my eyes while getting all those macros in shape again. Some started wandering off it seems. > >> + BTRFS_ATTR_PTR(raid, total_bytes)) >> val += block_group->key.offset; >> else >> val += btrfs_block_group_used(&block_group->item); >> @@ -331,19 +332,20 @@ SPACE_INFO_ATTR(bytes_may_use); >> SPACE_INFO_ATTR(bytes_readonly); >> SPACE_INFO_ATTR(disk_used); >> SPACE_INFO_ATTR(disk_total); >> -BTRFS_ATTR(total_bytes_pinned, btrfs_space_info_show_total_bytes_pinned); >> +BTRFS_ATTR(space_info, total_bytes_pinned, \ > > same here. will be fixed at commit time. > >> + btrfs_space_info_show_total_bytes_pinned); >> -- Hans van Kranenburg -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html