On Wednesday, November 02, 2011, Oleg Nesterov wrote: > Hi, > > On 11/01, Tejun Heo wrote: > > > > For now, let's go with the count/dont_count. Can you please write up > > a patch for that? Jeff, does this seem okay to you? > > OK, will do in a minute. On top of > "[PATCH pm] freezer: fix wait_event_freezable/__thaw_task races" > you sent. (btw, thanks, I forgout about it ;) > > Rafael, could you remind why freezer_do_not_count/freezer_count check > ->mm != NULL ? You're asking difficult questions. ;-) The intention was to prevent PF_FREEZER_SKIP from having any effect on kernel threads, IIRC. Anyway, there are only two legitimate users of it (vfork and apm_ioctl) and in both cases the task in question is user space. > The comment says "However, we don't want kernel threads to be frozen", > but it is not clear anyway. A kernel thread simply shouldn't use this > interface if it doesn't want to freeze. > > And in any case, PF_KTHREAD looks better if we really need to filter > out the kernel threads. PF_FREEZER_SKIP was introduced specifically with vfork in mind and I'm not sure if it's a good idea to re-use it for something else (at least not for something entirely obvious). Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
