On Thu 20-04-23 12:02:44, Ojaswin Mujoo wrote: > On Sat, Mar 25, 2023 at 08:12:36PM +0530, Ojaswin Mujoo wrote: > > On Thu, Mar 23, 2023 at 11:55:37AM +0100, Jan Kara wrote: > > > On Fri 17-03-23 15:56:46, Ojaswin Mujoo wrote: > > > > On Thu, Mar 09, 2023 at 01:11:22PM +0100, Jan Kara wrote: > > > > > Also when going for symbolic allocator scan names maybe we could actually > > > > > make names sensible instead of CR[0-4]? Perhaps like CR_ORDER2_ALIGNED, > > > > > CR_BEST_LENGHT_FAST, CR_BEST_LENGTH_ALL, CR_ANY_FREE. And probably we could > > > > > deal with ordered comparisons like in: > > > > I like this idea, it should make the code a bit more easier to > > > > understand. However just wondering if I should do it as a part of this > > > > series or a separate patch since we'll be touching code all around and > > > > I don't want to confuse people with the noise :) > > > > > > I guess a mechanical rename should not be really confusing. It just has to > > > be a separate patch. > > Alright, got it. > > > > > > > > > > > > > if (cr < 2 && > > > > > (!sbi->s_log_groups_per_flex || > > > > > ((group & ((1 << sbi->s_log_groups_per_flex) - 1)) != 0)) & > > > > > !(ext4_has_group_desc_csum(sb) && > > > > > (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)))) > > > > > return 0; > > > > > > > > > > to declare CR_FAST_SCAN = 2, or something like that. What do you think? > > > > About this, wont it be better to just use something like > > > > > > > > cr < CR_BEST_LENGTH_ALL > > > > > > > > instead of defining a new CR_FAST_SCAN = 2. > > > > > > Yeah, that works as well. > > > > > > > The only concern is that if we add a new "fast" CR (say between > > > > CR_BEST_LENGTH_FAST and CR_BEST_LENGTH_ALL) then we'll need to make > > > > sure we also update CR_FAST_SCAN to 3 which is easy to miss. > > > > > > Well, you have that problem with any naming scheme (and even with numbers). > > > So as long as names are all defined together, there's reasonable chance > > > you'll remember to verify the limits still hold :) > > haha that's true. Anyways, I'll try a few things and see what looks > > good. Thanks for the suggestions. > Hey Jan, > > So I was playing around with this and I prepare a patch to convert CR > numbers to symbolic names and it looks good as far as things like these > are concerned: > > if (cr < CR_POWER2_ALIGNED) > ... > > However there's one problem that this numeric naming scheme is used in > several places like struct member names, function names, traces and > comments. The issue is that replacing it everywhere is making some of > the names very long for example: > > atomic_read(&sbi->s_bal_cr0_bad_suggestions)); > > becomes: > > atomic_read(&sbi->s_bal_cr_power2_aligned_bad_suggestions)); > > And this is kind of making the code look messy at a lot of places. So > right now there are a few options we can consider: > > 1. Use symbolic names everywhere at the cost of readability Can we maybe go with 1b) being: Use symbolic names in variables / members / ... but shortened? Like s_bal_p2aligned_bad_suggestions? Not sure how many things are like this but from a quick looks it seems we need to come up with a sensible shortcut only for cr0 and cr1? Honza -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
