Em Tue, 13 Aug 2013 23:02:08 +0530 "Naveen N. Rao" <naveen.n.rao@xxxxxxxxxxxxxxxxxx> escreveu: > On 08/13/2013 06:12 PM, Borislav Petkov wrote: > > On Tue, Aug 13, 2013 at 04:51:33PM +0530, Naveen N. Rao wrote: > >> You're right - my trace point makes all the data provided by apei > >> as-is to userspace. However, ghes_edac seems to squash some of this > >> data into a string when reporting through mc_event. > > > > Right, for systems which don't need EDAC to decode to the DIMM or for > > which there are no EDAC drivers written, they could use a tracepoint > > which carries APEI info as-is. Others, which need EDAC, should probably > > use trace_mc_event and disable the APEI tracepoint. > > If I'm not mistaken, even for systems that have EDAC drivers, it looks > to me like EDAC can't really decode to the DIMM given what is provided > by the bios in the APEI report currently. Yes, the current APEI events, reported via EDAC, can't be decoded currently. > If and when ghes_edac gains > this capability, users will have a choice between raw APEI reports vs. > edac processed ones. An APEI-specific tracing won't fix it, as, AFAIKT, we don't have any way to map it, even on userspace. > > > > > I think this should address Tony's concerns... > > > > Btw, you could call your TP something simpler like > > trace_ghes_memory_event or so. > > I started out with a simpler name, but eventually decided to use the > name from the CPER record so it is clear what this event carries. I > think this will be better when adding further ghes events for say, > processor generic, PCIe and others. > > > > > Btw 2, if GHES can report other types of errors (I'm pretty sure it can) > > maybe we can use a single tracepoint called trace_ghes_event for any > > types of errors coming out of it... > > Two problems with this: > - One, the record size will be really big since the cper records for > each type of error is large. > - Two, it may be better to filter events based on the type of error > (memory error, processor, pcie, ...) rather than subscribing for all > ghes error reports. I agree: per-type of error events is better than a big generic one. > > > > > Oh, and while at it, we probably need to start thinking of a mechanism > > to disable all the error printing, i.e. cper_print_mem() and such, > > if a userspace agent is listening in on the tracepoint and the error > > information is carried through it to userspace. > > Do you mean conditionally print the cper records based on whether the > tracepoint is enabled or not? Wouldn't that be confusing if someone is > monitoring dmesg as well? > > > Thanks, > Naveen > -- Cheers, Mauro -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
