lix/src/libstore/cgroup.cc
2020-07-06 13:50:33 +02:00

67 lines
1.8 KiB
C++

#if __linux__
#include "cgroup.hh"
#include "util.hh"
#include <chrono>
#include <dirent.h>
namespace nix {
std::map<std::string, std::string> getCgroups(const Path & cgroupFile)
{
std::map<std::string, std::string> cgroups;
for (auto & line : tokenizeString<std::vector<std::string>>(readFile(cgroupFile), "\n")) {
static std::regex regex("([0-9]+):([^:]*):(.*)");
std::smatch match;
if (!std::regex_match(line, match, regex))
throw Error("invalid line '%s' in '%s'", line, cgroupFile);
std::string name = hasPrefix(match[2], "name=") ? std::string(match[2], 5) : match[2];
cgroups.insert_or_assign(name, match[3]);
}
return cgroups;
}
void destroyCgroup(const Path & cgroup)
{
for (auto & entry : readDirectory(cgroup)) {
if (entry.type != DT_DIR) continue;
destroyCgroup(cgroup + "/" + entry.name);
}
int round = 1;
while (true) {
auto pids = tokenizeString<std::vector<std::string>>(readFile(cgroup + "/cgroup.procs"));
if (pids.empty()) break;
if (round > 20)
throw Error("cannot kill cgroup '%s'", cgroup);
for (auto & pid_s : pids) {
pid_t pid;
if (!string2Int(pid_s, pid)) throw Error("invalid pid '%s'", pid);
// FIXME: pid wraparound
if (kill(pid, SIGKILL) == -1 && errno != ESRCH)
throw SysError("killing member %d of cgroup '%s'", pid, cgroup);
}
auto sleep = std::chrono::milliseconds((int) std::pow(2.0, std::min(round, 10)));
printError("waiting for %d ms for cgroup '%s' to become empty", sleep.count(), cgroup);
std::this_thread::sleep_for(sleep);
round++;
}
if (rmdir(cgroup.c_str()) == -1)
throw SysError("deleting cgroup '%s'", cgroup);
}
}
#endif