On 20/02/17 17:18, Alexander Shishkin wrote: > Alexander Shishkin <[email protected]> writes: > >> With the vmm_exclusive=0, PT seems to be much more usable on BDW now. This >> patchset does three things: >> * adds a flag to PERF_RECORD_AUX, signalling that a transaction has gaps >> in it (due to VMX root mode kicking in), > > Hi Arnaldo & Adrian, > > In the above context, will something like this be fine?
Looks fine to me. Acked-by: Adrian Hunter <[email protected]> > > Regards, > -- > Alex > >>From 5aba03e79c1119408b44435af8c4cee2480b0775 Mon Sep 17 00:00:00 2001 > From: Alexander Shishkin <[email protected]> > Date: Mon, 20 Feb 2017 17:08:53 +0200 > Subject: [PATCH] perf tools: Handle partial AUX records and print a warning > > This patch decodes the 'partial' flag in AUX records and prints > a warning to the user, so that they don't have to guess why their > PT traces contain gaps (or missing altogether): > >> Warning: >> AUX data had gaps in it 6 times out of 8! >> >> Are you running a KVM guest in the background? > > Currently this is the only reason for partial records. > > Cc: Adrian Hunter <[email protected]> > Signed-off-by: Alexander Shishkin <[email protected]> > --- > tools/include/uapi/linux/perf_event.h | 1 + > tools/perf/util/event.c | 5 +++-- > tools/perf/util/event.h | 1 + > tools/perf/util/session.c | 17 ++++++++++++++--- > 4 files changed, 19 insertions(+), 5 deletions(-) > > diff --git a/tools/include/uapi/linux/perf_event.h > b/tools/include/uapi/linux/perf_event.h > index c66a485a24..8306415207 100644 > --- a/tools/include/uapi/linux/perf_event.h > +++ b/tools/include/uapi/linux/perf_event.h > @@ -885,6 +885,7 @@ enum perf_callchain_context { > */ > #define PERF_AUX_FLAG_TRUNCATED 0x01 /* record was truncated > to fit */ > #define PERF_AUX_FLAG_OVERWRITE 0x02 /* snapshot from > overwrite mode */ > +#define PERF_AUX_FLAG_PARTIAL 0x04 /* record contains gaps > */ > > #define PERF_FLAG_FD_NO_GROUP (1UL << 0) > #define PERF_FLAG_FD_OUTPUT (1UL << 1) > diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c > index 4ea7ce72ed..ba193cd019 100644 > --- a/tools/perf/util/event.c > +++ b/tools/perf/util/event.c > @@ -1153,11 +1153,12 @@ int perf_event__process_exit(struct perf_tool *tool > __maybe_unused, > > size_t perf_event__fprintf_aux(union perf_event *event, FILE *fp) > { > - return fprintf(fp, " offset: %#"PRIx64" size: %#"PRIx64" flags: > %#"PRIx64" [%s%s]\n", > + return fprintf(fp, " offset: %#"PRIx64" size: %#"PRIx64" flags: > %#"PRIx64" [%s%s%s]\n", > event->aux.aux_offset, event->aux.aux_size, > event->aux.flags, > event->aux.flags & PERF_AUX_FLAG_TRUNCATED ? "T" : "", > - event->aux.flags & PERF_AUX_FLAG_OVERWRITE ? "O" : ""); > + event->aux.flags & PERF_AUX_FLAG_OVERWRITE ? "O" : "", > + event->aux.flags & PERF_AUX_FLAG_PARTIAL ? "P" : ""); > } > > size_t perf_event__fprintf_itrace_start(union perf_event *event, FILE *fp) > diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h > index c735c53a26..d7e53fe176 100644 > --- a/tools/perf/util/event.h > +++ b/tools/perf/util/event.h > @@ -269,6 +269,7 @@ struct events_stats { > u64 total_lost; > u64 total_lost_samples; > u64 total_aux_lost; > + u64 total_aux_partial; > u64 total_invalid_chains; > u32 nr_events[PERF_RECORD_HEADER_MAX]; > u32 nr_non_filtered_samples; > diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c > index 4cdbc8f5f1..abdb797fa4 100644 > --- a/tools/perf/util/session.c > +++ b/tools/perf/util/session.c > @@ -1258,9 +1258,12 @@ static int machines__deliver_event(struct machines > *machines, > case PERF_RECORD_UNTHROTTLE: > return tool->unthrottle(tool, event, sample, machine); > case PERF_RECORD_AUX: > - if (tool->aux == perf_event__process_aux && > - (event->aux.flags & PERF_AUX_FLAG_TRUNCATED)) > - evlist->stats.total_aux_lost += 1; > + if (tool->aux == perf_event__process_aux) { > + if (event->aux.flags & PERF_AUX_FLAG_TRUNCATED) > + evlist->stats.total_aux_lost += 1; > + if (event->aux.flags & PERF_AUX_FLAG_PARTIAL) > + evlist->stats.total_aux_partial += 1; > + } > return tool->aux(tool, event, sample, machine); > case PERF_RECORD_ITRACE_START: > return tool->itrace_start(tool, event, sample, machine); > @@ -1548,6 +1551,14 @@ static void perf_session__warn_about_errors(const > struct perf_session *session) > stats->nr_events[PERF_RECORD_AUX]); > } > > + if (session->tool->aux == perf_event__process_aux && > + stats->total_aux_partial != 0) { > + ui__warning("AUX data had gaps in it %" PRIu64 " times out of > %u!\n\n" > + "Are you running a KVM guest in the > background?\n\n", > + stats->total_aux_partial, > + stats->nr_events[PERF_RECORD_AUX]); > + } > + > if (stats->nr_unknown_events != 0) { > ui__warning("Found %u unknown events!\n\n" > "Is this an older tool processing a perf.data " >
