Well that's an interesting one!
Apparently if you issue multiple concurrent preadv calls on
a TUN device using io_uring, the TUN device falls over.
Possibly corrupting memory along the way.
Which might be why the kernel hung on shutdown...
avoids a per-packet alloc
i will atone for my sins later
if only C let you return multiple values.
or Go let you pass in a pointer w/o it being on the heap.
logBufWriter had no serialization.
It just so happens that none of its users currently ever log concurrently.
Make it safe for concurrent use.
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
Regression from 6d10655dc3, which added
UpdatePrefs but didn't write it out to disk.
I'd planned on adding tests to state_test.go which is why I'd earlier
added 46896a9311 to prepare for making
such persistence tests easier to write, but turns out state_test.go
didn't even test UpdatePrefs, so I'm staying out of there.
Instead, this is tested using integration tests.
Fixes#2321
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
As Brad suggested, mem.RO allows for a lot of easy perf gains. There were also some smaller
changes outside of mem.RO, such as using hex.Decode instead of hex.DecodeString.
```
name old time/op new time/op delta
FromUAPI-8 14.7µs ± 3% 12.3µs ± 4% -16.58% (p=0.008 n=5+5)
name old alloc/op new alloc/op delta
FromUAPI-8 9.52kB ± 0% 7.04kB ± 0% -26.05% (p=0.008 n=5+5)
name old allocs/op new allocs/op delta
FromUAPI-8 77.0 ± 0% 29.0 ± 0% -62.34% (p=0.008 n=5+5)
```
Signed-off-by: julianknodt <julianknodt@gmail.com>
Adds a benchmark for FromUAPI in wgcfg.
It appears that it's not actually that slow, the main allocations are from the scanner and new
config.
Updates #1912.
Signed-off-by: julianknodt <julianknodt@gmail.com>
My spatial memory functions poorly with large files and the vms_test.go
file recently surpassed the point where it functions adequately. This
patch splits up vms_test.go into more files to make my spatial memory
function like I need it to.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
Split from https://github.com/tailscale/tailscale/pull/2376.
This adds IPv6 support to testcontrol so each member of the tailscale
network gets an IPv6 address too.
Signed-off-by: Christine Dodrill <xe@tailscale.com>
It was once believed that it might be useful. It wasn't. We never used it.
Remove it so we don't slowly leak memory.
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
In theory, some of the other table-driven tests could be moved into this
form now but I didn't want to disturb too much good test code.
Includes a commented-out test for #2384 that is currently failing.
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
The DERPTestPort int meant two things before: which port to use, and
whether to disable TLS verification. Users would like to set the port
without disabling TLS, so break it into two options.
Updates #1264
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Josh Bleecher Snyder
Brad Fitzpatrick
julianknodt
Christine Dodrill
Dan Bond
maddie
David Crawshaw
David Anderson
Simeng He