On Thu 05-11-15 17:30:14, aris@xxxxxxxxxx wrote: > This patchset lays the foundation work to allow using dump_stack() with a > specified printk log level. Currently each architecture uses a different > log level in show_stack() and it's not possible to control it without > calling directly architecture specific functions. > > The motivation behind this work is to limit the amount of kernel messages > printed in the console when a process is killed by the OOM killer. In some > scenarios (lots of containers running different customers' workloads) OOMs > are way more common and don't require the console to be flooded by stack > traces when the OOM killer probably did the right choice. During a recent > discussion it was determined that a knob to control when dump_stack() is > called is a bad idea and instead we should tune the log level in dump_stack() > which prompted this work. > > This patchset introduces two new functions: > dump_stack_lvl(char *log_lvl) > show_stack_lvl(struct task_struct *task, unsigned long *sp, char *log_lvl) > > and both can be reimplemented by each architecture but only the second is > expected. The idea is to initially implement show_stack_lvl() in all > architectures then simply have show_stack() to require log_lvl as parameter. > While that happens, dump_stack() uses can be changed to dump_stack_lvl() and > once everything is in place, dump_stack() will require the log_level as well. This looks good to me FWIW. > I have a draft patch for every architecture but for this patchset I'm only > including x86 to get some feedback while I try to get a cross compiler working > for each one of them (which is being harder than I thought). > > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > Cc: Ingo Molnar <mingo@xxxxxxxxxx> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxxxxx> > Cc: Greg Thelen <gthelen@xxxxxxxxxx> > Cc: Johannes Weiner <hannes@xxxxxxxxxxx> > Cc: David Rientjes <rientjes@xxxxxxxxxx> > Signed-off-by: Aristeu Rozanski <aris@xxxxxxxxxx> > > -- > Aristeu -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>