On Thu, Apr 25, 2024 at 08:34:57 +0200, Michal Privoznik wrote: > The "quantum" attribute of HTB is documented as: > > Number of bytes to serve from this class before the scheduler > moves to the next class. > > Since v1.3.2-rc1~225 we compute what we think is the appropriate > value and pass it on the TC command line. But kernel and > subsequently TC use uint32_t to store this value. If we compute > value outside of this type then TC fails and prints usage which > we then interpret as an error message. Needlessly long error > message. While there's not much we can do about the latter, we > can put a cap on the value and stop tickling this behavior of TC. > > Fixes: 065054daa71f645fc83aff0271f194d326208616 > Resolves: https://issues.redhat.com/browse/RHEL-34112 > Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx> > --- > src/util/virnetdevbandwidth.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/src/util/virnetdevbandwidth.c b/src/util/virnetdevbandwidth.c > index ec41666f67..7f5714a33f 100644 > --- a/src/util/virnetdevbandwidth.c > +++ b/src/util/virnetdevbandwidth.c > @@ -46,6 +46,7 @@ virNetDevBandwidthCmdAddOptimalQuantum(virCommand *cmd, > const virNetDevBandwidthRate *rate) > { > const unsigned long long mtu = 1500; > + const unsigned long long r2q_limit = (1ULL << 32) -1; This quacks like 'UINT32_MAX' > unsigned long long r2q; > > /* When two or more classes compete for unused bandwidth they are each > @@ -60,6 +61,11 @@ virNetDevBandwidthCmdAddOptimalQuantum(virCommand *cmd, > if (!r2q) > r2q = 1; > > + /* But there's an internal limit in TC (well, kernel's implementation of > + * HTB) for quantum: it has to fit into u32. Put a cap there. */ > + if (r2q > r2q_limit) > + r2q = r2q_limit; And you could use the constant directly here, which would also address the broken spacing around subtraction in the variable you've added. Reviewed-by: Peter Krempa <pkrempa@xxxxxxxxxx> _______________________________________________ Devel mailing list -- devel@xxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxx
