Hi, Ok, early testing shows that this seems to be working fine with the pid approach. Of course it is less convenient than just opening a file descriptor in cgroup_fs. There is more bookkeeping involved, incl. cleanup the child on exit.
The other thing is related to how to indicate we want cgroup and not per-thread. For now, my patch is using a new attr.cgroup bit. The alternative is to use a bit in the flags parameter to the syscall. On Wed, Sep 22, 2010 at 11:18 AM, Balbir Singh <bal...@linux.vnet.ibm.com> wrote: > * Peter Zijlstra <pet...@infradead.org> [2010-09-22 09:27:59]: > >> On Wed, 2010-09-22 at 09:53 +0530, Balbir Singh wrote: >> > Yes, a task can belong to multiple subsystems, hence multiple cgroups. >> > Ideally we'd want to use pid + subsystem >> >> Apparently we create a perf subsystem, and we only care about that. So >> pid will uniquely identify a cgroup, since for each subsystem a task can >> only belong to one cgroup. > > Hmm.. I misread the intention to mean we care about monitoring all > data and aggregate it for each cgroup. > >> >> > > One thing we could do is pass this cgroup identifier in the pid field >> > > and use PERF_FLAG_CGROUP or something. Currently the syscall signature >> > > uses pid_t, but I think we can safely change that to int. >> > >> > Or union it and overload the field to contain either pid_t or fd of the >> > cgroup >> >> Its not a field, its an argument. > > Thanks! > > -- > Three Cheers, > Balbir > ------------------------------------------------------------------------------ Start uncovering the many advantages of virtual appliances and start using them to simplify application deployment and accelerate your shift to cloud computing. http://p.sf.net/sfu/novell-sfdev2dev _______________________________________________ perfmon2-devel mailing list perfmon2-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/perfmon2-devel
