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Date: Tue, 24 Nov 2015 14:27:08 +0900 From: Namhyung Kim <namhyung@...nel.org> To: Frederic Weisbecker <fweisbec@...il.com> CC: Arnaldo Carvalho de Melo <arnaldo.melo@...il.com>, Ingo Molnar <mingo@...nel.org>, linux-kernel@...r.kernel.org, Andi Kleen <andi@...stfloor.org>, David Ahern <dsahern@...il.com>, Jiri Olsa <jolsa@...hat.com>, Kan Liang <kan.liang@...el.com>, Peter Zijlstra <a.p.zijlstra@...llo.nl>, Arnaldo Carvalho de Melo <acme@...hat.com> Subject: Re: [PATCH 34/37] perf hists browser: Support flat callchains On Mon, Nov 23, 2015 at 04:16:48PM +0100, Frederic Weisbecker wrote: > On Thu, Nov 19, 2015 at 02:53:20PM -0300, Arnaldo Carvalho de Melo wrote: > > From: Namhyung Kim <namhyung@...nel.org> > > > > The flat callchain mode is to print all chains in a single, simple > > hierarchy so make it easy to see. > > > > Currently perf report --tui doesn't show flat callchains properly. With > > flat callchains, only leaf nodes are added to the final rbtree so it > > should show entries in parent nodes. To do that, add parent_val list to > > struct callchain_node and show them along with the (normal) val list. > > > > For example, consider following callchains with '-g graph'. > > > > $ perf report -g graph > > - 39.93% swapper [kernel.vmlinux] [k] intel_idle > > intel_idle > > cpuidle_enter_state > > cpuidle_enter > > call_cpuidle > > - cpu_startup_entry > > 28.63% start_secondary > > - 11.30% rest_init > > start_kernel > > x86_64_start_reservations > > x86_64_start_kernel > > > > Before: > > $ perf report -g flat > > - 39.93% swapper [kernel.vmlinux] [k] intel_idle > > 28.63% start_secondary > > - 11.30% rest_init > > start_kernel > > x86_64_start_reservations > > x86_64_start_kernel > > > > After: > > $ perf report -g flat > > - 39.93% swapper [kernel.vmlinux] [k] intel_idle > > - 28.63% intel_idle > > cpuidle_enter_state > > cpuidle_enter > > call_cpuidle > > cpu_startup_entry > > start_secondary > > - 11.30% intel_idle > > cpuidle_enter_state > > cpuidle_enter > > call_cpuidle > > cpu_startup_entry > > start_kernel > > x86_64_start_reservations > > x86_64_start_kernel > > > > Signed-off-by: Namhyung Kim <namhyung@...nel.org> > > Tested-by: Arnaldo Carvalho de Melo <acme@...hat.com> > > Tested-by: Brendan Gregg <brendan.d.gregg@...il.com> > > Cc: Andi Kleen <andi@...stfloor.org> > > Cc: David Ahern <dsahern@...il.com> > > Cc: Frederic Weisbecker <fweisbec@...il.com> > > Cc: Jiri Olsa <jolsa@...hat.com> > > Cc: Kan Liang <kan.liang@...el.com> > > Cc: Peter Zijlstra <a.p.zijlstra@...llo.nl> > > Link: http://lkml.kernel.org/r/1447047946-1691-8-git-send-email-namhyung@kernel.org > > Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com> > > --- > > [...] > > > +int callchain_node__make_parent_list(struct callchain_node *node) > > +{ > > + struct callchain_node *parent = node->parent; > > + struct callchain_list *chain, *new; > > + LIST_HEAD(head); > > + > > + while (parent) { > > + list_for_each_entry_reverse(chain, &parent->val, list) { > > + new = malloc(sizeof(*new)); > > + if (new == NULL) > > + goto out; > > + *new = *chain; > > + new->has_children = false; > > + list_add_tail(&new->list, &head); > > + } > > + parent = parent->parent; > > + } > > + > > + list_for_each_entry_safe_reverse(chain, new, &head, list) > > + list_move_tail(&chain->list, &node->parent_val); > > + > > + if (!list_empty(&node->parent_val)) { > > + chain = list_first_entry(&node->parent_val, struct callchain_list, list); > > + chain->has_children = rb_prev(&node->rb_node) || rb_next(&node->rb_node); > > + > > + chain = list_first_entry(&node->val, struct callchain_list, list); > > + chain->has_children = false; > > I'm a bit puzzled with this, can't we rewind through the parents on printing or adding > to the flat rbtree instead of having this parent_val field? Yes, this code is to simplify things on parent nodes. Maybe we could go up to parents and print the callchain list there as you said. However, problem I think is how to handle 'has_children' information on parents. That info controls folding status of each callchain. As the info is in the struct callchain_list and flat or folded callchain mode require the info should be in the top-most entry, I cannot share entries in parent nodes. Thus I simply copied callchain lists in parents to leaf nodes. Yes, it will consume some memory but can simplify the code. Thank you for your review anyway! Namhyung -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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