Use nr_hugepages from /proc/cmdline

Currently Proxmox VE always deallocates HugePagesTLB
when starting a new machine and it makes it impossible
to preconfigure kernel /proc/cmdline with persistent allocation.

This change makes deallocation to prefer defaults set by /proc/cmdline,
by parsing the cmdline and respecting hugepages= and hugepagesz=.

Signed-off-by: Kamil Trzciński <ayufan@ayufan.eu>
This commit is contained in:
Kamil Trzciński 2019-02-17 13:39:37 +01:00 committed by Wolfgang Bumiller
parent f5c673cba7
commit ca0ef6b148

View File

@ -538,6 +538,29 @@ sub hugepages_allocate {
}
sub hugepages_default_nr_hugepages {
my ($size) = @_;
my $cmdline = PVE::Tools::file_read_firstline("/proc/cmdline");
my $args = PVE::Tools::split_args($cmdline);
my $parsed_size = 2; # default is 2M
foreach my $arg (@$args) {
if ($arg eq "hugepagesz=2M") {
$parsed_size = 2;
} elsif ($arg eq "hugepagesz=1G") {
$parsed_size = 1024;
} elsif ($arg =~ m/^hugepages=(\d+)?$/) {
if ($parsed_size == $size) {
return $1;
}
}
}
return 0;
}
sub hugepages_pre_deallocate {
my ($hugepages_topology) = @_;
@ -545,8 +568,8 @@ sub hugepages_pre_deallocate {
my $hugepages_size = $size * 1024;
my $path = "/sys/kernel/mm/hugepages/hugepages-${hugepages_size}kB/";
my $hugepages_nr = PVE::Tools::file_read_firstline($path."nr_hugepages");
PVE::ProcFSTools::write_proc_entry($path."nr_hugepages", 0);
my $hugepages_nr = hugepages_default_nr_hugepages($size);
PVE::ProcFSTools::write_proc_entry($path."nr_hugepages", $hugepages_nr);
}
}