Re: [PATCH v2 1/2] perf hist: Deduplicate cmp/sort/collapse code

Dmitry Vyukov
2025-01-15T08:02:23Z

On Wed, 15 Jan 2025 at 02:07, Namhyung Kim <namhyung@kernel.org> wrote:
>
> On Mon, Jan 13, 2025 at 02:34:14PM +0100, Dmitry Vyukov wrote:
> > Application of cmp/sort/collapse fmt callbacks is duplicated 6 times.
> > Factor it into a common helper function. NFC.
> >
> > Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
> > Cc: Namhyung Kim <namhyung@kernel.org>
> > Cc: Ian Rogers <irogers@google.com>
> > Cc: linux-perf-users@vger.kernel.org
> > Cc: linux-kernel@vger.kernel.org
> >
> > ---
> >
> > Changes in v2:
> > - add perf_hpp_fmt_cmp_t typedef to util/hist.h
> > - use the typedef for perf_hpp_fmt::{cmp,collapse,sort}
> > ---
> > tools/perf/util/hist.c | 103 +++++++++++++++++------------------------
> > tools/perf/util/hist.h | 14 +++---
> > 2 files changed, 49 insertions(+), 68 deletions(-)
> >
> > diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
> > index fff1345658016..a4b8ec3805565 100644
> > --- a/tools/perf/util/hist.c
> > +++ b/tools/perf/util/hist.c
> > @@ -32,6 +32,9 @@
> > #include <linux/time64.h>
> > #include <linux/zalloc.h>
> >
> > +static int64_t hist_entry__cmp(struct hist_entry *left, struct hist_entry *right);
> > +static int64_t hist_entry__collapse(struct hist_entry *left, struct hist_entry *right);
> > +
> > static bool hists__filter_entry_by_dso(struct hists *hists,
> > struct hist_entry *he);
> > static bool hists__filter_entry_by_thread(struct hists *hists,
> > @@ -1292,19 +1295,26 @@ int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
> > return err;
> > }
> >
> > -int64_t
> > -hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
> > +static int64_t
> > +hist_entry__cmp_impl(struct perf_hpp_list *hpp_list, struct hist_entry *left,
> > + struct hist_entry *right, unsigned long fn_offset,
> > + bool ignore_dynamic, bool ignore_skipped)
>
> Maybe it's a matter of tastes, but I think it could be simpler like
> below.
>
> > {
> > struct hists *hists = left->hists;
> > struct perf_hpp_fmt *fmt;
> > int64_t cmp = 0;
> > + perf_hpp_fmt_cmp_t fn;
>
> perf_hpp_fmt_cmp_t *fn;
>
> >
> > - hists__for_each_sort_list(hists, fmt) {
> > - if (perf_hpp__is_dynamic_entry(fmt) &&
> > + perf_hpp_list__for_each_sort_list(hpp_list, fmt) {
> > + if (ignore_dynamic && perf_hpp__is_dynamic_entry(fmt) &&
> > !perf_hpp__defined_dynamic_entry(fmt, hists))
> > continue;
> >
> > - cmp = fmt->cmp(fmt, left, right);
> > + if (ignore_skipped && perf_hpp__should_skip(fmt, hists))
> > + continue;
> > +
> > + fn = *(perf_hpp_fmt_cmp_t *)(((char *)fmt) + fn_offset);
> > + cmp = fn(fmt, left, right);
>
> fn = (void *)fmt + fn_offset;
> cmp = (*fn)(fmt, left, right);

Done in v3.

> Otherwise, looks good to me.

Thanks for the review.

> Thanks,
> Namhyung
>
> > if (cmp)
> > break;
> > }
> > @@ -1313,23 +1323,33 @@ hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
> > }
> >
> > int64_t
> > -hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
> > +hist_entry__cmp(struct hist_entry *left, struct hist_entry *right)
> > {
> > - struct hists *hists = left->hists;
> > - struct perf_hpp_fmt *fmt;
> > - int64_t cmp = 0;
> > + return hist_entry__cmp_impl(left->hists->hpp_list, left, right,
> > + offsetof(struct perf_hpp_fmt, cmp), true, false);
> > +}
> >
> > - hists__for_each_sort_list(hists, fmt) {
> > - if (perf_hpp__is_dynamic_entry(fmt) &&
> > - !perf_hpp__defined_dynamic_entry(fmt, hists))
> > - continue;
> > +static int64_t
> > +hist_entry__sort(struct hist_entry *left, struct hist_entry *right)
> > +{
> > + return hist_entry__cmp_impl(left->hists->hpp_list, left, right,
> > + offsetof(struct perf_hpp_fmt, sort), false, true);
> > +}
> >
> > - cmp = fmt->collapse(fmt, left, right);
> > - if (cmp)
> > - break;
> > - }
> > +int64_t
> > +hist_entry__collapse(struct hist_entry *left, struct hist_entry *right)
> > +{
> > + return hist_entry__cmp_impl(left->hists->hpp_list, left, right,
> > + offsetof(struct perf_hpp_fmt, collapse), true, false);
> > +}
> >
> > - return cmp;
> > +static int64_t
> > +hist_entry__collapse_hierarchy(struct perf_hpp_list *hpp_list,
> > + struct hist_entry *left,
> > + struct hist_entry *right)
> > +{
> > + return hist_entry__cmp_impl(hpp_list, left, right,
> > + offsetof(struct perf_hpp_fmt, collapse), false, false);
> > }
> >
> > void hist_entry__delete(struct hist_entry *he)
> > @@ -1503,14 +1523,7 @@ static struct hist_entry *hierarchy_insert_entry(struct hists *hists,
> > while (*p != NULL) {
> > parent = *p;
> > iter = rb_entry(parent, struct hist_entry, rb_node_in);
> > -
> > - cmp = 0;
> > - perf_hpp_list__for_each_sort_list(hpp_list, fmt) {
> > - cmp = fmt->collapse(fmt, iter, he);
> > - if (cmp)
> > - break;
> > - }
> > -
> > + cmp = hist_entry__collapse_hierarchy(hpp_list, iter, he);
> > if (!cmp) {
> > he_stat__add_stat(&iter->stat, &he->stat);
> > return iter;
> > @@ -1730,24 +1743,6 @@ int hists__collapse_resort(struct hists *hists, struct ui_progress *prog)
> > return 0;
> > }
> >
> > -static int64_t hist_entry__sort(struct hist_entry *a, struct hist_entry *b)
> > -{
> > - struct hists *hists = a->hists;
> > - struct perf_hpp_fmt *fmt;
> > - int64_t cmp = 0;
> > -
> > - hists__for_each_sort_list(hists, fmt) {
> > - if (perf_hpp__should_skip(fmt, a->hists))
> > - continue;
> > -
> > - cmp = fmt->sort(fmt, a, b);
> > - if (cmp)
> > - break;
> > - }
> > -
> > - return cmp;
> > -}
> > -
> > static void hists__reset_filter_stats(struct hists *hists)
> > {
> > hists->nr_non_filtered_entries = 0;
> > @@ -2449,21 +2444,15 @@ static struct hist_entry *add_dummy_hierarchy_entry(struct hists *hists,
> > struct rb_node **p;
> > struct rb_node *parent = NULL;
> > struct hist_entry *he;
> > - struct perf_hpp_fmt *fmt;
> > bool leftmost = true;
> >
> > p = &root->rb_root.rb_node;
> > while (*p != NULL) {
> > - int64_t cmp = 0;
> > + int64_t cmp;
> >
> > parent = *p;
> > he = rb_entry(parent, struct hist_entry, rb_node_in);
> > -
> > - perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
> > - cmp = fmt->collapse(fmt, he, pair);
> > - if (cmp)
> > - break;
> > - }
> > + cmp = hist_entry__collapse_hierarchy(he->hpp_list, he, pair);
> > if (!cmp)
> > goto out;
> >
> > @@ -2521,16 +2510,10 @@ static struct hist_entry *hists__find_hierarchy_entry(struct rb_root_cached *roo
> >
> > while (n) {
> > struct hist_entry *iter;
> > - struct perf_hpp_fmt *fmt;
> > - int64_t cmp = 0;
> > + int64_t cmp;
> >
> > iter = rb_entry(n, struct hist_entry, rb_node_in);
> > - perf_hpp_list__for_each_sort_list(he->hpp_list, fmt) {
> > - cmp = fmt->collapse(fmt, iter, he);
> > - if (cmp)
> > - break;
> > - }
> > -
> > + cmp = hist_entry__collapse_hierarchy(he->hpp_list, iter, he);
> > if (cmp < 0)
> > n = n->rb_left;
> > else if (cmp > 0)
> > diff --git a/tools/perf/util/hist.h b/tools/perf/util/hist.h
> > index 1131056924d9c..46c8373e31465 100644
> > --- a/tools/perf/util/hist.h
> > +++ b/tools/perf/util/hist.h
> > @@ -342,8 +342,6 @@ int hist_entry_iter__add(struct hist_entry_iter *iter, struct addr_location *al,
> > struct perf_hpp;
> > struct perf_hpp_fmt;
> >
> > -int64_t hist_entry__cmp(struct hist_entry *left, struct hist_entry *right);
> > -int64_t hist_entry__collapse(struct hist_entry *left, struct hist_entry *right);
> > int hist_entry__transaction_len(void);
> > int hist_entry__sort_snprintf(struct hist_entry *he, char *bf, size_t size,
> > struct hists *hists);
> > @@ -452,6 +450,9 @@ struct perf_hpp {
> > bool skip;
> > };
> >
> > +typedef int64_t (*perf_hpp_fmt_cmp_t)(
> > + struct perf_hpp_fmt *, struct hist_entry *, struct hist_entry *);
> > +
> > struct perf_hpp_fmt {
> > const char *name;
> > int (*header)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
> > @@ -463,12 +464,9 @@ struct perf_hpp_fmt {
> > struct hist_entry *he);
> > int (*entry)(struct perf_hpp_fmt *fmt, struct perf_hpp *hpp,
> > struct hist_entry *he);
> > - int64_t (*cmp)(struct perf_hpp_fmt *fmt,
> > - struct hist_entry *a, struct hist_entry *b);
> > - int64_t (*collapse)(struct perf_hpp_fmt *fmt,
> > - struct hist_entry *a, struct hist_entry *b);
> > - int64_t (*sort)(struct perf_hpp_fmt *fmt,
> > - struct hist_entry *a, struct hist_entry *b);
> > + perf_hpp_fmt_cmp_t cmp;
> > + perf_hpp_fmt_cmp_t collapse;
> > + perf_hpp_fmt_cmp_t sort;
> > bool (*equal)(struct perf_hpp_fmt *a, struct perf_hpp_fmt *b);
> > void (*free)(struct perf_hpp_fmt *fmt);
> >
> > --
> > 2.47.1.688.g23fc6f90ad-goog
> >