Quoting Lionel Landwerlin (2018-02-12 10:37:52) > On 09/02/18 20:53, Chris Wilson wrote: > > Quoting Lionel Landwerlin (2018-02-09 17:47:44) > >> Hey Chris, > >> > >> From the i915/perf point of view, I'm fine with this change. > >> The pinning of the hw_id when monitoring a single context (with OA) > >> doesn't break the existing userspace (I can only think of Mesa). > >> > >> I'm also trying to build up a system wide monitoring feature in GPUTop > >> with a timeline display. This change makes it a bit more challenging. > >> But this isn't really an expected feature, it's just nice to have. > >> > >> What I'm thinking of would be to keep a circular buffer of requests in > >> the order they're submitted to an engine. > >> Then the i915 perf driver could correlate between the context-switch > >> tagged reports coming from OA and the requests submitted. > >> Much like the OA buffer, this circular buffer could overflow at which > >> point we signal the application using the i915 perf driver and it'll > >> most likely close the driver and try again. > >> > >> I would need that have the hw_id added to the requests. Does that sounds > >> possible? > > You already add hw_id to the tracepoint. For the requests, it is just > > req->ctx->hw_id, valid from submission to retirement. Hmm, the > > tracepoint is broken (use-after-free in ctx->hw_id). What value do you > > want for HSW? (This patch will assign all legacy submission to HW ID 0.) > > But aiui, for HSW oa you want lrca not HW ID. So both the use-after-free > > and alternative ids suggest storing it on the request directly. > > HSW doesn't have a hw_id field in the OA reports. > I'll have to come up with something slightly different. > > > > > How do you get the HW ID out, via the tracepoint right? > > It's in the OA reports. I mean how do you correlate the HW ID with userspace? -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
