On 07.10.21 11:37, Dominik Csapak wrote:
> saves a list of pciid <-> vmid mappings in /var/run
> that we can check when we start a vm
>
> if we're not given a pid but a timeout, we save the time when the
> reservation will run out (current time + timeout + 5s) since each
> vm start (until we can save the pid) varies from config to config
>
a few comments, some of them could have happend for v1 so sorry for any
churn..
> Signed-off-by: Dominik Csapak <d.csa...@proxmox.com>
> ---
> PVE/QemuServer/PCI.pm | 99 +++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 99 insertions(+)
>
> diff --git a/PVE/QemuServer/PCI.pm b/PVE/QemuServer/PCI.pm
> index 5608207..364ceb7 100644
> --- a/PVE/QemuServer/PCI.pm
> +++ b/PVE/QemuServer/PCI.pm
> @@ -5,6 +5,7 @@ use strict;
>
> use PVE::JSONSchema;
> use PVE::SysFSTools;
> +use PVE::Tools;
>
> use base 'Exporter';
>
> @@ -461,4 +462,102 @@ sub print_hostpci_devices {
> return ($kvm_off, $gpu_passthrough, $legacy_igd);
> }
>
> +my $PCIID_RESERVATION_FILE = "/var/run/pve-reserved-pciids";
> +my $PCIID_RESERVATION_LCK = "/var/lock/pve-reserved-pciids.lck";
> +
> +my $parse_pci_reservation = sub {
> + my $pciids = {};
> +
> + if (my $fh = IO::File->new ($PCIID_RESERVATION_FILE, "r")) {
> + while (my $line = <$fh>) {
> + if ($line =~ m/^($PCIRE)\s(\d+)\stime\:(\d+)$/) {
> + $pciids->{$1} = {
> + vmid => $2,
> + timestamp => $3,
> + };
> + } elsif ($line =~ m/^($PCIRE)\s(\d+)\spid\:(\d+)$/s) {
> + $pciids->{$1} = {
> + vmid => $2,
> + pid => $3,
> + };
> + }
could probably be (untested):
if ($line =~ m/^($PCIRE)\s(\d+)\s(time|pid)\:(\d+)$/) {
$pciids->{$1} = {
vmid => $2,
"$3" => $4,
};
}
Alternative: use a format like "$vmid $timestamp [$pid]"
we'd keep the time of initial reservation info that way, not sure how much use
that
has though ^^
> + }
> + }
> +
> + return $pciids;
> +};
> +
> +my $write_pci_reservation = sub {
> + my ($pciids) = @_;
> +
> + my $data = "";
> + foreach my $p (keys %$pciids) {
> + my $entry = $pciids->{$p};
> + if (defined($entry->{pid})) {
> + $data .= "$p $entry->{vmid} pid:$entry->{pid}\n";
> + } else {
> + $data .= "$p $entry->{vmid} time:$entry->{timestamp}\n";
> + }
> + }
> +
> + PVE::Tools::file_set_contents($PCIID_RESERVATION_FILE, $data);
> +};
> +
> +sub remove_pci_reservation {
> + my ($id) = @_;
it could be an optimization to allow passing a array ref of IDs, less
open+writes+rename,
while thanks to /run being a tmpfs no IO is happening but syscalls are
expensive, so
when they're as easy to reduce as here I'd opt for that. Could do the same in a
similar
spirit for registering then.
> +
> + my $code = sub {
> + my $pciids = $parse_pci_reservation->();
> +
> + delete $pciids->{$id};
> +
> + $write_pci_reservation->($pciids);
> + };
> +
> + PVE::Tools::lock_file($PCIID_RESERVATION_LCK, 10, $code);
> + die $@ if $@;
> +
> + return;
> +}
> +
> +sub reserve_pci_usage {
> + my ($id, $vmid, $timeout, $pid) = @_;
> +
> + PVE::Tools::lock_file($PCIID_RESERVATION_LCK, 10, sub {
> +
> + my $ctime = time();
> + my $errmsg = "PCI device '$id' already in use\n";
> +
> + my $pciids = $parse_pci_reservation->();
> +
> + if (my $pciid = $pciids->{$id}) {
> + if ($pciid->{vmid} != $vmid) {
> + # check time based reservation
> + die $errmsg if defined($pciid->{timestamp}) &&
> $pciid->{timestamp} > $ctime;
> +
> + # check running vm
> + my $pid =
> PVE::QemuServer::Helpers::vm_running_locally($pciid->{vmid});
> + die $errmsg if defined($pciid->{pid}) && $pid == $pciid->{pid};
Maybe we should warn in the != case, as that would mean a registration was not
cleaned up nicely and recording that in the task log should not hurt.
> + }
> + }
> +
> + $pciids->{$id} = {
> + vmid => $vmid,
> + };
> + if (defined($timeout)) {
> + # we save the timestamp when the reservation gets invalid (+5s),
> + # since the start timeout depends on the config
> + $pciids->{$id}->{timestamp} = $ctime + $timeout + 5;
> + }
> + $pciids->{$id}->{pid} = $pid if defined($pid);
> +
> + $write_pci_reservation->($pciids);
> +
> + return;
> + });
> + die $@ if $@;
> +
> + return;
> +}
> +
> 1;
>
_______________________________________________
pve-devel mailing list
pve-devel@lists.proxmox.com
https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel
