<mrvn>
Nice. On ARM you have to do that manually if you make the kernel/irqs reentrant.
<mrvn>
If you forget then double register load/store may fail.
<zid>
That's useful to know first hand
<zid>
that you technically need to oversize interrupt frames by 8 in case it realigned
<zid>
(easier than making sure that struct is 16 aligned at that member, anyway)
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<mrvn>
zid: alignas(16) is pretty simple.
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<ddevault>
ACPI NVS regions, should the OS just never touch them and let the hardware use it as it likes, or will the OS ever have to read/write it for something
<heat>
you don't touch them
<heat>
you just need to make sure you don't :)
<heat>
(some of it also isn't "non-volatile storage" but don't tell anyone about that)
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<heat>
wait a sec, is there an OpRegion for this? I don't thin kso
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<heat>
ddevault, actually you may need to touch it
<heat>
I forgot that some ACPI tables are required to point into NVS
<heat>
an easy example is the new wakeup thing in the MADT
<ddevault>
thanks heat, will keep that in mind
<heat>
np
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<geist>
mrvn: i should point out that arm64 tightens that even more
<geist>
You must have the stack 16 byte aligned *always*
<heat>
isn't that something you explicitly enable?
<geist>
As in the instant you add or load it with something that isn’t 16 byte aligned it throws an exception
<geist>
It is, but virtually all systems set it, and i think it will become mandatory at some point
<geist>
They only added the chicken bit for existing legacy code
<geist>
And because of arm32 compatibility
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<geist>
But it also solves the ‘align the stack on exception entry’ problem, since it maintains the invariant that the stack is always aligned, and thus by definition on exception entry it is aligned
<geist>
If you unset the bit you’d probably be on the hook to align it
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<heat>
geist, o' geist of the depths
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<heat>
i need your wisedom
<heat>
how guilty should I feel for my new allocator consuming a bunch more memory than it did?
<heat>
a part of me thinks that it's not a problem because I can just reclaim everything and hopefully things go back to normal
<heat>
but it definitely feels less flexible
<heat>
right?
<heat>
not that I'm targetting those small embedded systems but I can definitely see how all of this percpu crazyness can lead to less efficient memory usage
<heat>
I see why one would not do this for e.g lk
<heat>
otoh, what is memory for if it's not being actively used
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<geist>
Yah and in fact gotta do more percpu stuff in lk
<geist>
I figure if you're doing percpu then you're doing smp and that's almost never a memory constrained situation
<mjg>
you should feel guilty for using c++, heat
<heat>
right, but otoh
<heat>
my system is using up 70MB of pages at /bin/dash time
<heat>
after a relatively simple boot
<heat>
it used to use ~20MB
<mjg>
do you have accounting for it?
<mjg>
what is what
<geist>
Seems a bit excessive yes
<heat>
mjg: it's all caches
<heat>
and I'm using a relatively smaller percpu cache than what linux was using *in 2000*
<mjg>
but do you have exact numbers
<mjg>
or are just handwaving
<geist>
Seems a bit much to prefill then too much
<mjg>
you do realize you can do memory usage flamegraphs? :)
<geist>
Sure but linux in 2000 generally didn't deal with as many cpus as we do now
<geist>
Maybe that was too much back then too
<mjg>
look man for all i know you just brainfarted somewhere and are allocating more than you think
<mjg>
absent exact numbers one can only speculate
<mjg>
you are worried about a factor -> make sure your system provides visibility into it
<heat>
let me reimplement purge
<heat>
i have good indication that most of it really is just stuck on magazines
<heat>
I'm keeping at most 128 of each object < PAGE_SIZE
<heat>
my batch size is 64
<geist>
Probably a bit much yeah
<geist>
If you have 20 slabs or so that'll add up quick
<mjg>
whoa ye
<heat>
either this is a really deficient design and linux was wrong or they do their page reclaiming a lot more aggressively
<heat>
which makes sense
<geist>
Perhaps having a per object tunable so things that think they'll need it can request larger caches at creation
<mjg>
so normally you want this to autotune itself
<mjg>
unless you know for a fact certain limit is best for given obj type
<geist>
Also linux in 2000 was kinda a toy
<mjg>
OH!
<geist>
A 2 core cpu was still fairly exotic etx
<mjg>
well ye it was basically crap, but good enough for all major players to decide it is worth investing in
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<geist>
Sure was the start of the rise of Linux
<geist>
I just remember at arihnd 2000 if you wanted a serious system you probably ran bsd or one of the big unices
<mjg>
right
<geist>
By mid to late 2000 linux was starting to take over
<mjg>
from what i'm told even then there were plans(tm) to replace them with linux
<mjg>
at yahoo etc
<geist>
Yah
<geist>
I'm not entirely sure what the issue was with bsd at the time. Maybe folks were still leery because of the att lawsuit
<geist>
I at the time had assumed it would be where all the money would go
<geist>
But maybe linux was more free for development wise so it got more energy
<geist>
And after a while it was inevitable
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<mjg>
i only found highly contradictory claims
<geist>
Yah
<geist>
Unclear where the truth lies there
<mjg>
most notably ones claiming the lawsuit was irrelevant
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<mjg>
as much as i'm happy to shit on the old unix systems, linux was always a hackjob
<geist>
Possible it was simply the bad community being kinda fractured and more... Stodgy maybe
<geist>
Bsd not bad
<mjg>
ye i'm not gonna rant about it today
<mjg>
but it was very much bad :)
<geist>
Nod. Anyway gottw go. At airport waiting for plane
<mjg>
funny bit re that
<mjg>
i was watching youtube videos where profesionals from given industry describe how it differs from portrayal in movies
<mjg>
i got to a video of a flight attendant
<mjg>
a clip from a movie was played where people were singing on the plane, including flight attendants
<mjg>
the FA commenting said this totally would not happen
<mjg>
... but i was on a flight where something of the sort did happen. it was a very small plane, mostly empty at that
<mjg>
some dudez were very chatty and started flirting with one of the two flight attendants
<mjg>
and the she sang!
<mjg>
then*
<heat>
weird
<mjg>
i did not mind
<zid>
And then the americans all clapped
<mjg>
i don't know if any americans were there
<heat>
murica
<zid>
well if nobody clapped, there weren't any
<heat>
lets play football and baseball
<heat>
and have weird chants
<ddevault>
every so often I read through the Intel HD graphics manuals until my eyes bleed
<zid>
Nice
<heat>
bad idea
<mjg>
oh no
<ddevault>
it does not typically take long
<zid>
I've never owned intel HD graphics or I might have too
<mjg>
want to get to a point where you don't need the driver
<mjg>
causey ou can't see anyway?
<ddevault>
brilliant
<heat>
outstanding
<zid>
if I had a testbench with gma I probably would have given it a go
<mjg>
brilliant.org
<heat>
get any cheap cpu+mobo made in the last idk, 10 years?
<zid>
and psu and ram and monitor and keyboard and mouse
<zid>
and make room on a desk
<ddevault>
my goal is to bring up my laptop's VGA port and stick a framebuffer on it
<zid>
and storage, and network cable
<heat>
for a testbench? you don't need most of that
<ddevault>
I'm still a ways out from having enough of the prerequisites in place, though
<heat>
>VGA port
<heat>
LMAO
<zid>
I mean, you can ignore the mouse
<zid>
I want a busted up laptop with vga and hdmi
<zid>
so I can use it as an arcade machine
<zid>
write some bios tetris for it
<mjg>
that's some kink you got there
<zid>
I think I could probably fit tgm3 into bios, and then provide the audio via storage
<zid>
hot swappable bgm
<zid>
oh duh, the obvious solution to audio is to burn it to a cd-rom ofc
<zid>
and use the dedicated cd-audio cable to bypass setting up the soundcard
<heat>
mjg, lmao, linux's solution is "reap all the caches 2 times a second"
<mjg>
heat: 19:45 < mjg> as much as i'm happy to shit on the old unix systems, linux was always a hackjob
<heat>
I actually
<heat>
I bug have
<heat>
I bug fix
<heat>
ooga booga heat dumb
<heat>
I was accidentally ignoring the NOPCPU flag on kfree which essentially made large (> PAGE_SIZE) objects hostage
<heat>
now im back to 21MB
<heat>
which is Decent(tm)
<mjg>
19:35 < mjg> look man for all i know you just brainfarted somewhere and are allocating more than you think
<mjg>
19:35 < mjg> absent exact numbers one can only speculate
<mjg>
19:35 < mjg> you are worried about a factor -> make sure your system provides visibility into it
<mjg>
some hard earned wisdom right there motherf^Wman
<heat>
so im basically doing what's supposed to happen for a normal slab allocator, except I don't do weird caching things which don't seem to be worth it
<heat>
I have percpu caches, sized up to 128, or 64 if size > 256, 32 if size > 1024
<heat>
I allocate in batches of pcpu_size / 2
<mjg>
so what'st he perf now
<heat>
2.3M
<mjg>
that's from 1.7-ish?
<mjg>
you should keep a sheet somewhere
<heat>
originally 1.6, then 2.0M, then 1.9M, now 2.3M
<heat>
anyway, the allocator is no longer a bottleneck
<mjg>
right on
<mjg>
bonwick wants his royalties tho
<heat>
a funny thing is that I don't cache >=PAGE_SIZE'd objects in pcpu caches (because that's just a poor idea)
<heat>
and for really really large objects (right now I'm cutting the threshold on 128KiB) I just free any slab as soon as I can
<heat>
because those slabs are HUGE
<heat>
each slab is PAGE_SIZE sized except when objsize > PGSZ/8, where I just size it up to PAGE_ALIGN(24 * objsize)
<heat>
I noticed I was doing rare, very large allocations sometimes which basically held a bunch of objects hostage in free slabs
<mjg>
i wrote a special cased allocator for relaly big stuff
<mjg>
have not pushed it yet though
<heat>
yeah
<heat>
I usually just vmalloc for those
<mjg>
simple fucker with a list, alloc/free in fifo policy
<heat>
which is essentially a wavl tree lookup + memory pool alloc (which is stupid simple but has a lock) + page allocation
<mjg>
per numa domain
<heat>
>numa domain
<heat>
LMAO
<heat>
not going down that rabbithole
<mjg>
:)
<mjg>
i'm saying you can whip out the special case allocator within minutes
<mjg>
no magazine or whatever tf
<mjg>
and portected with a lock
<heat>
I also realized linux separates slab lists per node
<mjg>
you have to do it to to prevent degradation in perf
<mjg>
things go way down if you get memory from non-local node
<heat>
sometimes when worse comes to worst they snipe other nodes' memory but... yeah
<geist>
everyone nodes that!
<heat>
Welcome to Node.js v18.10.0.
<heat>
Type ".help" for more information.
<heat>
>
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<heat>
Uncaught SyntaxError: Invalid or unexpected token
<heat>
^^^^^^^^^^^^^^^
<qookie>
oops dang
<sham1>
Reading /etc/shadow would probably not do you much good anyway since the passwords are hashed
<heat>
and /etc/shadow/ isn't a thing
<heat>
and node isn't root
<geist>
what does readFileSync do? the sync part in particular?
<geist>
i guess that's versus some sort of async model?
<heat>
probably
<heat>
80% of js is async
<geist>
seems a bit extraneous to call it out, but i guess whatever that api is wants to be clear
<heat>
I guess this saves you the await
<geist>
oh is that js? aaah makes sense
<geist>
i was thinking C# or something
<heat>
yeah node.js
<mjg>
sham1: see jackthreripper
<geist>
i have thus far managed to write i think zero lines of javascript
<mjg>
+1
<mjg>
no js club unite
<mjg>
node js club please gtfo
<qookie>
heat: yeah i missed the ' and pressed the / that's below it :^)
<geist>
oh hmm now that i think about it i futzed with it maybe one night, in a moment of weakness. just wanted to see how easy it was to blat stuff on a Canvas
<mjg>
you are unpure now, geist
<sham1>
And yeah, `readFileSync` blocks while reading
<geist>
we all have our weaknesses, it's good to admit it and live with your limitations
<heat>
i've written javascript before
<heat>
I felt clueless
<sham1>
I have to write it at work
<heat>
then I had to mess with
<heat>
FUCKING REACT
<geist>
that's my general problem with languages where it's less the language and more of whatever framework du jour it is
<geist>
i dont like dealing with layers of frameworks. feels much less fruitful than deeply grokking some language fundamentally
<heat>
tbf javascript is more standardized than ever
<geist>
oh sure, but AFAICT no one really writes Pure Javascript right?
<geist>
ie you pretty quickly pull in some large thing that you implement against
<geist>
i say this as i get ready to board a plane for pleasure. CO2 wants to be free!
<mats1>
mining is a lot cheaper with renewables
<heat>
geist, lmao, I love it
<heat>
oops
<heat>
GeDaMo,
<GeDaMo>
:D
<heat>
... fighting muscle memory is herd
<mjg>
blame it on irssi
<heat>
i don't use irssi
<Arsen>
do it anyway!
<mjg>
you don't type nicks, do you?
<heat>
mjg: how do I easily look at a slab's pcpu caches without adding atomics or locks?
<heat>
I thought of just IPI'ing but they still get IRQs in nopreempt zones
<heat>
i assume adding a lock there is something you would consider Pessimal(tm)
<mjg>
look from where
<mjg>
at another cpu's caches?
<heat>
yeah
<mjg>
in general you should not do it to begin with
<heat>
I know
<heat>
I'm talking about purge()
<mjg>
why dyou even want one
<mjg>
you got unloadable kernel modules?
<heat>
to slim down on slabs if I need to
<heat>
yes
<mjg>
don't lie to me
<heat>
i do
<mjg>
i noted i would do it with IPIs
<mjg>
the ipi handler would check if it is in a spot where it can do what you need
<mjg>
if not, gives you an error and you spin a little and try again
<heat>
AH WAIT YES
<heat>
I can just have a CPU local counter
<heat>
pretty cheap
<heat>
pcpu->accessing++; if (pcpu->accessing >= 0) return;
<heat>
makes sense
<heat>
what do kernel modules have to do with this?
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<mjg>
kernel modules may want to create their own slabs
<mjg>
if you unload, you whack them
<mjg>
but you may have per-cpu cachen from there
<mjg>
so
<mjg>
that needs to go away somehow
<heat>
I haven't used kernel modules in a long time
<mjg>
here is my proposal with more details
<heat>
I think they work but i dunno
<mjg>
the fast path would be one small routine, preemption disabled around it
<heat>
and unloading is something I've never supported
<mjg>
past that the only accesses to even per-cpu magazines are with the slab lock
<mjg>
then the ipi handler checks if the fast path is interrupted. if so, buggers off. if not, whacks the magazines
<mjg>
replaces with empty ones
<mjg>
that wya you get no pessimization for the common case
<mjg>
and you still can take the cached stuff if needed
<mjg>
i think this is a very low priority though
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<heat>
you're a very low priority
<mjg>
i'm -20
<heat>
the lowest niceness ever
<mjg>
ye i'm not very nice, am i
<heat>
exactly
<heat>
still the nicest BSD person ever
<mjg>
that is close to correct
<mjg>
people will pretend to be nice and whatnot, all until you pose legit criticism of their code
<mjg>
then real personalities come up
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<mjg>
and let me tell ya, denial is stronk
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<heat>
well tbf that's understandable
<heat>
who hasn't got upset over that?
<zid>
mjg: My code is flawless, it's the methodology that is rudamentary
<zid>
rudimentary, like my spelling
<mjg>
heat: i did not
<mjg>
in fact i can point you at code i wrote which i later determined to be crap
<heat>
sure
<mjg>
which is also fixed by now
<heat>
but have you never felt attacked when someone was criticizing your shit?
<mjg>
i did felt attacked, but all the cricisim was wrong, so there is that
<mjg>
dude asserted "no way", could have trivially tested im right but did not, instead wrote a long e-mail with lolo tests which were not representative of what the code is doing
<mjg>
so i walked him through testing on his own and he conceeded
<mjg>
to give you one example
<mjg>
perhaps the crux is to not implement your shit idea before validating it
<mats1>
you're not my real dad
<mjg>
i had shit ideas which i scrapped on my own, i also had people point out they would not work before i really put effort into them
<mjg>
so i'm playing easy mode here so to speak
<mjg>
now there is code which i consider pretty decent, if that turned out to be total crap i would defo be a sad panda
<mjg>
but i don't think i would lie about it
<mjg>
as in claim it is good should evidence to he contrary be presented
<heat>
I don't think anyone writes code going "hehehe this is so shit and they'll love every second of it"
<heat>
so everyone feels either attacked or sad panda
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<mjg>
heat: bro
<heat>
brother
<mjg>
heat: people wriet code like "well fuck it just get this over with"
<ddevault>
rest assured that notifications are mostly referred to as notes
<ddevault>
and endpoints as ep
<mjg>
that's still a little verbose
<mjg>
also you may want to add a shitty letter
<ddevault>
n, e
<mjg>
which is misleading
<ddevault>
nopte
<mjg>
+1
<mjg>
i just rememberd a unix tool named after someone's dog
<mjg>
this fucking system
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<mrvn>
mjg: it only gets worse with time, not better.
<mrvn>
or it's the second level of the effect where people that know a little think they know it all
<mrvn>
Want to know what's frustrating? I once made a PR for zeromq to add a data structure with the expressed purposed to have constant time insert and cancel. The author first accepted the PR and then changed the data structure. Guess what he changed: insertion and cancel now run in O(log n).
<mjg>
lol
<mjg>
how is lookup?
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<mrvn>
O(1) if you have a handle. no search or O(n).
<mrvn>
O(1) min and amortized O(log n) tick
<mrvn>
if you haven't figured it out it was a priority queue with delayed work, specialized of timers getting canceled frequently.
<mjg>
maybe they would not change struct if they got the ha bench
<mrvn>
If he didn't liḱe the code he shouldn't have accepted the PR in the first place.
<mjg>
you are ranting at the wrong tree
<mrvn>
apropo tree. I want to plant trees in factorio. Anyone know a good mod for it?
<mrvn>
.oO(he says and goes completely off-topic)
<froggey>
I think there's a mod that lets you load trees (or tree seeds?) into artillery cannons
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<mrvn>
and it shoots and where the seed lands a tree appears?
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<heat>
wazap
<heat>
im bacc
<heat>
mjg, hello mjg
<heat>
what does freebsd use for page allocation?
<heat>
kthx
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<heat>
I'm not entirely convinced @ buddy allocation due to the pathological "I just want 4KB so I'll need to break down 4MB into teeny tiny pieces"
<heat>
but I'm also not convinced at stupid dumb "linked list of pages"
<heat>
particularly because it's hell getting contiguous stuff which doesn't allow for large pages and allocation directly on top of the direct map
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<mjg>
not ranting about it today
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<heat>
i dont need a rant
<mjg>
there is really nasty code for "super page reservartions"
<heat>
I just need an algo
<heat>
aw
<heat>
so the answer is "yes"?
<mjg>
yes to what
<mjg>
i don't know the whole algo, there are is a bunch of freelists
<mjg>
and "superpage reservartion array"
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<mjg>
when handing out pages for given vm objs, if there is a reservarton, it tries to stick to it
<mjg>
otherwise you get something else
<heat>
yeah that sounds like garbage
<mjg>
look man. there is 0 defrag support for any of it anyway
<mjg>
and over time the kernel loses ability to hand out large pages
<mjg>
even if you pretend this bit does not exist, handling of reservartions is so slow
<mjg>
the code was written with a single core mindset
<mjg>
and clearly only to publish a paper
<mjg>
you boot, get some large pages and life is great
<mjg>
who gives a fuck past that
<heat>
amen
<heat>
anyway my main gripe with all of this is that linux is the only OS out there (plus Fuchsia I guess) whose page allocation is a relatively standard and straightforward algo
<mjg>
i have no idea what others are *really* doing
<heat>
freebsd's algorithm seems to be "yes"
<heat>
I imagine netbsd and openbsd are either the same or more cursed
<mjg>
and i can't claim real expertise on this bit of fbsd either
<heat>
windows nt's page allocator is "who tf knows"
<mjg>
dude, that's not even fair to mention
<mjg>
you can shit on frebsd all you want, it does ultimately work with terabytes of ram if needed
<mjg>
which is not something i can say about certain other systems
<mjg>
(personally tested 4TB fwiw)
<heat>
freebsd has a lot more manpower than the other ones I assume
<heat>
also has other goals
<mjg>
it has more manpower
<mjg>
but also contrary to the other systems, it is used in production
<heat>
fwiw linux beats your ass anyway :D
<mjg>
not in every way
<mjg>
i got aspects of vfs faster, but it's only because in linux they decided to make it slow
<mjg>
not because i did anything genius
<heat>
sure
<heat>
but it's in almost every way superior, sorry
<heat>
how many million IOPS can they do now? it's kinda crazy
<heat>
you don't have that kind of investment anywhere else
<mjg>
you fucking name it, it would crash, give bad results or whatever
<heat>
let me guess
<heat>
poorly tested codepaths?
<mjg>
not exactly
<mjg>
but close
<heat>
genunix bad?
<mjg>
greatest fuzzer out there is your clientelle
<mjg>
some of the php websites were so fucking retarded you could not hope for a better fuzzer
<mjg>
every single php update i would get a bunch of customers getting core dumps
<mjg>
and the company had only ~100k sites
<heat>
sure but
<heat>
why would you not hit this on linux?
<mjg>
this was on linux
<heat>
hrm
<mjg>
where did i claim othewrise
<heat>
poopy
<heat>
I thought you were mentioning opensauce projects and freebsd
<mjg>
no, the list above is from my webhosting days
<mjg>
one funny bit
<mjg>
at my first job apache had certain patches because a certain module did not work otherwise
<mjg>
nobody upstreadmed them
<mjg>
at my 3rd job they decided to use said module and i had to re-create the patches to make it work
<mjg>
not upstreamed either
<mjg>
i strongly suspect this is custom-fixed in a number of companies, not one of which upstramed it
<mjg>
:)
<heat>
that actually brings me to an interesting question
<mjg>
there was a number of php patches as well, because guess what, php quickly stopped work with a number of popular sites
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<heat>
what's the legality of looking at some code with license A and then some time later rewriting or applying some of those principles on project B with license B
<mjg>
i don't know what you mean by "principles"
<heat>
i.e writing vfs code in linux, then years later working on freebsd's vfs
<heat>
how clouded can your mind be by GPLv2 in this instance
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<mjg>
literally imlpementing the same idea *which you spotted in other code* is not legal if the license prohibits it
<mjg>
implementing something which happens to line up with gpl code is easily happenstance, or even expected
<mjg>
like pagezero/clear_page using just rep stos
<heat>
so you pretend you've never seen it?
<mjg>
i have seen some of it and if anything it gave me a strong opinion how to NOT do stuff
<heat>
yeah sure
<heat>
that's not the point
<mjg>
it's a legit question, many companies would consinder you tainted
<mjg>
for example windows 2000 sources leaked years back
<mjg>
and if you had seen them, reactos requests you refrain from contributing
<heat>
yeah
<mjg>
realistically though, i can tell you people move between possibly competing products
<mjg>
and i guarantee there is some level of (un)intentional infiremented
<mjg>
most notably on patents
<heat>
infirewhat
<mjg>
infringement
<heat>
ah
<heat>
yeah I mean
<mjg>
realistically i don't htink you can work on more than 1 project and be considered pure
<mjg>
:>
<heat>
it's like you get the fucking avengers of kernel development and get them to work on the kernel
<heat>
they will have looked at stuff before
<mjg>
see above
<heat>
yea
<mjg>
everyone with serious experience is tainted
<heat>
i guess it's one of those legal grey areas
<mjg>
i know for a fact there is a certain lib which is very permisseivly licensed
<mjg>
which implements a recently patented algo
<mjg>
as in authors published a paper, that got an implementation by someone else, and they got a patent
<mjg>
the authors*
<mjg>
i did not message anyone about what it is cause you will get in shit for being told
<heat>
that seems wrong?
<mjg>
i'm saying this is not an isolated example
<mjg>
and i guarantee any non-trivial codebase infringes on *some* patents
<heat>
if you implement something pre-patent you shouldn't be able to retroactively be patent-fucked
<mjg>
this is why big corps also patent, so should anyone sue them, they can sue back
<mjg>
heat: not for implementing prior, but you can't use it after you became aware of the patent
<heat>
is this AT&T vs UC again? :v
<mjg>
in fact in most big corps if you get a message telling you about a patent
<mjg>
you need to forward it to the legal dept
<mjg>
infringing on a patent is one thing, doing it while knowing is another
<mjg>
should the lawsuit come
<mjg>
all this software patent business is total crapi mo, but what can you do
<heat>
i think they're not valid in some countries?
<mjg>
not valid in the eu
<mjg>
does noth elp when you are working on a global proejct
<heat>
Fedora's rpmfusion has a bunch of -freeworld packages with patent stuff enabled
<heat>
I know mesa has been in somewhat deepish shit for video acceleration on patented formats like MPEG4
<mjg>
i don't know about that bit
<heat>
and now fedora/ubuntu are disabling those codecs
<bslsk05>
jina-liu.medium.com: Settle your questions about H.264 license cost once and for all (hopefully) | by Jina Jiayang Liu | Medium
<heat>
this is kinda particularly problematic because youtube uses h264 :)
<mjg>
patent lawsuits are like nukes man
<mjg>
see oracle vs google re java
<clever>
heat: its also weird, that the rpi can do h264/h265 without any licensing fees, but mpeg2 and vc1 do need a fee
* heat
laughs in EU
<heat>
i guess I could legally implement RCU lmao
<clever>
RCU? read copy update?
<heat>
yes
<mjg>
actually you legally can
<mjg>
a number of patents has lapsed
<clever>
i would assume there are no patents on RCU, lol
<mjg>
i don't know what remains patented, i'm guessing it's stuff related to scaling it past a handful of cpus
<heat>
it's still a minefield of patents
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<heat>
if you read up on current RCU theory you'll probably violate a bunch of em
<heat>
clever, it's patented to shit by IBM
<heat>
I think they explicitly license it away to GPLv2 code? something like that
<mjg>
i know of certian US corps whose lawyers cleared local engineers to implement it
<mjg>
but ye, good luck sticking only to the patents
<mjg>
and not accidentaly improving on them in a way which infringers
<heat>
Define _LGPL_SOURCE (only) if your code is LGPL or GPL compatible before including the urcu.h or urcu-qsbr.h header. If your application is distributed under another license, function calls will be generated instead of inlines, so your application can link with the library.
<heat>
lmao
<heat>
for liburcu
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<clever>
heat: ive already read about RCU in some linux book, it seems so simple that it shouldnt be coverable under a patent?
<heat>
it's *not simple*
<mjg>
lol what
<mjg>
i would describe the simplest patent i know
<heat>
the base idea? sure, but even that can be lawyered into a patent
<mjg>
but i don't anyone in shit for coming up with the idea
<mjg>
:]
<Griwes>
Nothing should be coverable under a patent
<mjg>
rest assured it is osmething you come up with within minutes
<clever>
copy a the master pointer, and then from the data its pointing to, copy&mutate the structure
<Griwes>
But I believe we've had this exact conversation for this exact reason before
<mjg>
in fact if you dom ulticore stuff you probalby already did
<clever>
then use an atomic swap to change the master pointer to the new object, and put the old object on a queue
<heat>
clever, ok
<heat>
how do you make that *not slow*
<clever>
once every core has rescheduled at least once, free the old copy
<heat>
where you do free shit, when do you do that, and how
<heat>
there's a lot of nuance to rcu
<clever>
heat: thats why `iptables -A` gets slower over time and iptables-save is faster