[PATCH 0/3] perf annotate-data: Implement folding in TUI browser

[PATCH 0/3] perf annotate-data: Implement folding in TUI browser

[Namhyung Kim]

Hello,

I've implemented the folding logic to expand/collapse the current entry
in the TUI data type browser.  Users can use 'e' or 'E' to toggle the
entry (with or without children, respectively).

Ax example output looks like below.

  Annotate type: 'struct socket' (1 samples)
        Percent     Offset       Size  Field
  -      100.00          0        128  struct socket {                                  ◆
           0.00          0          4      socket_state   state;                        ▒
           0.00          4          2      short int      type;                         ▒
           0.00          8          8      long unsigned int      flags;                ▒
           0.00         16          8      struct file*   file;                         ▒
         100.00         24          8      struct sock*   sk;                           ▒
           0.00         32          8      struct proto_ops*      ops;                  ▒
  -        0.00         64         64      struct socket_wq       wq {                  ▒
  -        0.00         64         24          wait_queue_head_t  wait {                ▒
  +        0.00         64          4              spinlock_t     lock;                 ▒
  -        0.00         72         16              struct list_head       head {        ▒
           0.00         72          8                  struct list_head*  next;         ▒
           0.00         80          8                  struct list_head*  prev;         ▒
                                                   };                                   ▒
                                               };                                       ▒
           0.00         88          8          struct fasync_struct*      fasync_list;  ▒
           0.00         96          8          long unsigned int  flags;                ▒
  +        0.00        104         16          struct callback_head       rcu;          ▒
                                           };                                           ▒
                                       };                                               ▒

It hides the detail of spinlock_t and struct callback_head.

Thanks,
Namhyung


Namhyung Kim (3):
  perf annotate-data: Support folding in TUI browser
  perf annotate-data: Implement folding in TUI browser
  perf annotate-data: Show first-level children by default in TUI

 tools/perf/ui/browsers/annotate-data.c | 343 ++++++++++++++++++++++---
 1 file changed, 313 insertions(+), 30 deletions(-)

-- 
2.46.0.76.ge559c4bf1a-goog

[PATCH 1/3] perf annotate-data: Support folding in TUI browser

[Namhyung Kim]

Like in the hists browser, it should support folding current entry so
that it can hide unwanted details in some data structures.  The folded
entries will be displayed with '+' sign, while unfolded entries will
have '-' sign.  Entries have no children will not show any signs.

  Annotate type: 'struct socket' (1 samples)
        Percent     Offset       Size  Field
  -      100.00          0        128  struct socket {                                  ◆
           0.00          0          4      socket_state   state;                        ▒
           0.00          4          2      short int      type;                         ▒
           0.00          8          8      long unsigned int      flags;                ▒
           0.00         16          8      struct file*   file;                         ▒
         100.00         24          8      struct sock*   sk;                           ▒
           0.00         32          8      struct proto_ops*      ops;                  ▒
  -        0.00         64         64      struct socket_wq       wq {                  ▒
  -        0.00         64         24          wait_queue_head_t  wait {                ▒
  +        0.00         64          4              spinlock_t     lock;                 ▒
  -        0.00         72         16              struct list_head       head {        ▒
           0.00         72          8                  struct list_head*  next;         ▒
           0.00         80          8                  struct list_head*  prev;         ▒
                                                   };                                   ▒
                                               };                                       ▒
           0.00         88          8          struct fasync_struct*      fasync_list;  ▒
           0.00         96          8          long unsigned int  flags;                ▒
  +        0.00        104         16          struct callback_head       rcu;          ▒
                                           };                                           ▒
                                       };                                               ▒

This just adds the display logic for folding, actually folding action
will be implemented in the next patch.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/ui/browsers/annotate-data.c | 235 ++++++++++++++++++++++---
 1 file changed, 212 insertions(+), 23 deletions(-)

diff --git a/tools/perf/ui/browsers/annotate-data.c b/tools/perf/ui/browsers/annotate-data.c
index a937b55da736..04c73b67cd6c 100644
--- a/tools/perf/ui/browsers/annotate-data.c
+++ b/tools/perf/ui/browsers/annotate-data.c
@@ -14,6 +14,10 @@
 #include "util/evlist.h"
 #include "util/sort.h"
 
+#define FOLDED_SIGN  '+'
+#define UNFOLD_SIGN  '-'
+#define NOCHLD_SIGN  ' '
+
 struct annotated_data_browser {
 	struct ui_browser b;
 	struct list_head entries;
@@ -24,7 +28,11 @@ struct browser_entry {
 	struct list_head node;
 	struct annotated_member *data;
 	struct type_hist_entry *hists;
-	int indent;
+	struct browser_entry *parent;
+	struct list_head children;
+	int indent;  /*indentation level, starts from 0 */
+	int nr_entries; /* # of visible entries: self + descendents */
+	bool folded;  /* only can be false when it has children */
 };
 
 static struct annotated_data_browser *get_browser(struct ui_browser *uib)
@@ -65,13 +73,14 @@ static int get_member_overhead(struct annotated_data_type *adt,
 }
 
 static int add_child_entries(struct annotated_data_browser *browser,
+			     struct browser_entry *parent,
 			     struct annotated_data_type *adt,
 			     struct annotated_member *member,
 			     struct evsel *evsel, int indent)
 {
 	struct annotated_member *pos;
 	struct browser_entry *entry;
-	int nr_entries = 0;
+	struct list_head *parent_list;
 
 	entry = zalloc(sizeof(*entry));
 	if (entry == NULL)
@@ -84,36 +93,60 @@ static int add_child_entries(struct annotated_data_browser *browser,
 	}
 
 	entry->data = member;
+	entry->parent = parent;
 	entry->indent = indent;
 	if (get_member_overhead(adt, entry, evsel) < 0) {
 		free(entry);
 		return -1;
 	}
 
-	list_add_tail(&entry->node, &browser->entries);
-	nr_entries++;
+	INIT_LIST_HEAD(&entry->children);
+	if (parent)
+		parent_list = &parent->children;
+	else
+		parent_list = &browser->entries;
 
-	list_for_each_entry(pos, &member->children, node) {
-		int nr = add_child_entries(browser, adt, pos, evsel, indent + 1);
+	list_add_tail(&entry->node, parent_list);
 
+	list_for_each_entry(pos, &member->children, node) {
+		int nr = add_child_entries(browser, entry, adt, pos, evsel,
+					   indent + 1);
 		if (nr < 0)
 			return nr;
-
-		nr_entries += nr;
 	}
 
 	/* add an entry for the closing bracket ("}") */
 	if (!list_empty(&member->children)) {
-		entry = zalloc(sizeof(*entry));
-		if (entry == NULL)
+		struct browser_entry *bracket;
+
+		bracket = zalloc(sizeof(*bracket));
+		if (bracket == NULL)
 			return -1;
 
-		entry->indent = indent;
-		list_add_tail(&entry->node, &browser->entries);
-		nr_entries++;
+		bracket->indent = indent;
+		bracket->parent = entry;
+		bracket->folded = true;
+		bracket->nr_entries = 1;
+
+		INIT_LIST_HEAD(&bracket->children);
+		list_add_tail(&bracket->node, &entry->children);
 	}
 
-	return nr_entries;
+	/* fold child entries by default */
+	entry->folded = true;
+	entry->nr_entries = 1;
+	return 0;
+}
+
+static u32 count_visible_entries(struct annotated_data_browser *browser)
+{
+	int nr = 0;
+	struct browser_entry *entry;
+
+	list_for_each_entry(entry, &browser->entries, node)
+		nr += entry->nr_entries;
+
+	return nr;
 }
 
 static int annotated_data_browser__collect_entries(struct annotated_data_browser *browser)
@@ -123,9 +156,12 @@ static int annotated_data_browser__collect_entries(struct annotated_data_browser
 	struct evsel *evsel = hists_to_evsel(he->hists);
 
 	INIT_LIST_HEAD(&browser->entries);
+
+	add_child_entries(browser, /*parent=*/NULL, adt, &adt->self, evsel,
+			  /*indent=*/0);
+
 	browser->b.entries = &browser->entries;
-	browser->b.nr_entries = add_child_entries(browser, adt, &adt->self,
-						  evsel, /*indent=*/0);
+	browser->b.nr_entries = count_visible_entries(browser);
 	return 0;
 }
 
@@ -140,9 +176,155 @@ static void annotated_data_browser__delete_entries(struct annotated_data_browser
 	}
 }
 
+static struct browser_entry *get_first_child(struct browser_entry *entry)
+{
+	if (list_empty(&entry->children))
+		return NULL;
+
+	return list_first_entry(&entry->children, struct browser_entry, node);
+}
+
+static struct browser_entry *get_last_child(struct browser_entry *entry)
+{
+	if (list_empty(&entry->children))
+		return NULL;
+
+	return list_last_entry(&entry->children, struct browser_entry, node);
+}
+
+static bool is_first_child(struct browser_entry *entry)
+{
+	/* This will be checked in a different way */
+	if (entry->parent == NULL)
+		return false;
+
+	return get_first_child(entry->parent) == entry;
+}
+
+static bool is_last_child(struct browser_entry *entry)
+{
+	/* This will be checked in a different way */
+	if (entry->parent == NULL)
+		return false;
+
+	return get_last_child(entry->parent) == entry;
+}
+
+static struct browser_entry *browser__prev_entry(struct ui_browser *uib,
+						 struct browser_entry *entry)
+{
+	struct annotated_data_browser *browser = get_browser(uib);
+	struct browser_entry *first;
+
+	first = list_first_entry(&browser->entries, struct browser_entry, node);
+
+	while (entry != first) {
+		if (is_first_child(entry))
+			entry = entry->parent;
+		else {
+			entry = list_prev_entry(entry, node);
+			while (!entry->folded)
+				entry = get_last_child(entry);
+		}
+
+		if (!uib->filter || !uib->filter(uib, &entry->node))
+			return entry;
+	}
+	return first;
+}
+
+static struct browser_entry *browser__next_entry(struct ui_browser *uib,
+						 struct browser_entry *entry)
+{
+	struct annotated_data_browser *browser = get_browser(uib);
+	struct browser_entry *last;
+
+	last = list_last_entry(&browser->entries, struct browser_entry, node);
+	while (!last->folded)
+		last = get_last_child(last);
+
+	while (entry != last) {
+		if (!entry->folded)
+			entry = get_first_child(entry);
+		else {
+			while (is_last_child(entry))
+				entry = entry->parent;
+
+			entry = list_next_entry(entry, node);
+		}
+
+		if (!uib->filter || !uib->filter(uib, &entry->node))
+			return entry;
+	}
+	return last;
+}
+
+static void browser__seek(struct ui_browser *uib, off_t offset, int whence)
+{
+	struct annotated_data_browser *browser = get_browser(uib);
+	struct browser_entry *entry;
+
+	if (uib->nr_entries == 0)
+		return;
+
+	switch (whence) {
+	case SEEK_SET:
+		entry = list_first_entry(&browser->entries, typeof(*entry), node);
+		if (uib->filter && uib->filter(uib, &entry->node))
+			entry = browser__next_entry(uib, entry);
+		break;
+	case SEEK_CUR:
+		entry = list_entry(uib->top, typeof(*entry), node);
+		break;
+	case SEEK_END:
+		entry = list_last_entry(&browser->entries, typeof(*entry), node);
+		while (!entry->folded)
+			entry = get_last_child(entry);
+		if (uib->filter && uib->filter(uib, &entry->node))
+			entry = browser__prev_entry(uib, entry);
+		break;
+	default:
+		return;
+	}
+
+	assert(entry != NULL);
+
+	if (offset > 0) {
+		while (offset-- != 0)
+			entry = browser__next_entry(uib, entry);
+	} else {
+		while (offset++ != 0)
+			entry = browser__prev_entry(uib, entry);
+	}
+
+	uib->top = &entry->node;
+}
+
 static unsigned int browser__refresh(struct ui_browser *uib)
 {
-	return ui_browser__list_head_refresh(uib);
+	struct browser_entry *entry, *next;
+	int row = 0;
+
+	if (uib->top == NULL || uib->top == uib->entries)
+		browser__seek(uib, SEEK_SET, 0);
+
+	entry = list_entry(uib->top, typeof(*entry), node);
+
+	while (true) {
+		if (!uib->filter || !uib->filter(uib, &entry->node)) {
+			ui_browser__gotorc(uib, row, 0);
+			uib->write(uib, entry, row);
+			if (++row == uib->rows)
+				break;
+		}
+		next = browser__next_entry(uib, entry);
+		if (next == entry)
+			break;
+
+		entry = next;
+	}
+
+	return row;
 }
 
 static int browser__show(struct ui_browser *uib)
@@ -171,7 +353,7 @@ static int browser__show(struct ui_browser *uib)
 		strcpy(title, "Percent");
 
 	ui_browser__printf(uib, "%*s %10s %10s %10s  %s",
-			   11 * (browser->nr_events - 1), "",
+			   2 + 11 * (browser->nr_events - 1), "",
 			   title, "Offset", "Size", "Field");
 	ui_browser__write_nstring(uib, "", uib->width);
 	return 0;
@@ -208,12 +390,12 @@ static void browser__write(struct ui_browser *uib, void *entry, int row)
 	struct evsel *leader = hists_to_evsel(he->hists);
 	struct evsel *evsel;
 	int idx = 0;
+	bool current = ui_browser__is_current_entry(uib, row);
 
 	if (member == NULL) {
-		bool current = ui_browser__is_current_entry(uib, row);
-
 		/* print the closing bracket */
 		ui_browser__set_percent_color(uib, 0, current);
+		ui_browser__printf(uib, "%c ", NOCHLD_SIGN);
 		ui_browser__write_nstring(uib, "", 11 * browser->nr_events);
 		ui_browser__printf(uib, " %10s %10s  %*s};",
 				   "", "", be->indent * 4, "");
@@ -221,6 +403,13 @@ static void browser__write(struct ui_browser *uib, void *entry, int row)
 		return;
 	}
 
+	ui_browser__set_percent_color(uib, 0, current);
+
+	if (!list_empty(&be->children))
+		ui_browser__printf(uib, "%c ", be->folded ? FOLDED_SIGN : UNFOLD_SIGN);
+	else
+		ui_browser__printf(uib, "%c ", NOCHLD_SIGN);
+
 	/* print the number */
 	for_each_group_evsel(evsel, leader) {
 		struct type_hist *h = adt->histograms[evsel->core.idx];
@@ -237,13 +426,13 @@ static void browser__write(struct ui_browser *uib, void *entry, int row)
 		ui_browser__printf(uib, " %10d %10d  %s%s",
 				   member->offset, member->size,
 				   member->type_name,
-				   list_empty(&member->children) ? ";" : " {");
+				   list_empty(&member->children) || be->folded? ";" : " {");
 	} else {
 		ui_browser__printf(uib, " %10d %10d  %*s%s\t%s%s",
 				   member->offset, member->size,
 				   be->indent * 4, "", member->type_name,
 				   member->var_name ?: "",
-				   list_empty(&member->children) ? ";" : " {");
+				   list_empty(&member->children) || be->folded ? ";" : " {");
 	}
 	/* fill the rest */
 	ui_browser__write_nstring(uib, "", uib->width);
@@ -297,7 +486,7 @@ int hist_entry__annotate_data_tui(struct hist_entry *he, struct evsel *evsel,
 	struct annotated_data_browser browser = {
 		.b = {
 			.refresh = browser__refresh,
-			.seek	 = ui_browser__list_head_seek,
+			.seek	 = browser__seek,
 			.write	 = browser__write,
 			.priv	 = he,
 			.extra_title_lines = 1,
-- 
2.46.0.76.ge559c4bf1a-goog

[PATCH 2/3] perf annotate-data: Implement folding in TUI browser

[Namhyung Kim]

Like perf report, use 'e' or 'E' key to toggle folding the current entry
so that it can control displaying child entries.

Note I didn't add the 'c' and 'C' key to collapse the entry because it's
also handled with the 'e'/'E' since it toggles the state.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/ui/browsers/annotate-data.c | 98 ++++++++++++++++++++++++--
 1 file changed, 92 insertions(+), 6 deletions(-)

diff --git a/tools/perf/ui/browsers/annotate-data.c b/tools/perf/ui/browsers/annotate-data.c
index 04c73b67cd6c..a5c5ad63425e 100644
--- a/tools/perf/ui/browsers/annotate-data.c
+++ b/tools/perf/ui/browsers/annotate-data.c
@@ -18,12 +18,6 @@
 #define UNFOLD_SIGN  '-'
 #define NOCHLD_SIGN  ' '
 
-struct annotated_data_browser {
-	struct ui_browser b;
-	struct list_head entries;
-	int nr_events;
-};
-
 struct browser_entry {
 	struct list_head node;
 	struct annotated_member *data;
@@ -35,6 +29,13 @@ struct browser_entry {
 	bool folded;  /* only can be false when it has children */
 };
 
+struct annotated_data_browser {
+	struct ui_browser b;
+	struct list_head entries;
+	struct browser_entry *curr;
+	int nr_events;
+};
+
 static struct annotated_data_browser *get_browser(struct ui_browser *uib)
 {
 	return container_of(uib, struct annotated_data_browser, b);
@@ -302,6 +303,7 @@ static void browser__seek(struct ui_browser *uib, off_t offset, int whence)
 
 static unsigned int browser__refresh(struct ui_browser *uib)
 {
+	struct annotated_data_browser *browser = get_browser(uib);
 	struct browser_entry *entry, *next;
 	int row = 0;
 
@@ -314,6 +316,8 @@ static unsigned int browser__refresh(struct ui_browser *uib)
 		if (!uib->filter || !uib->filter(uib, &entry->node)) {
 			ui_browser__gotorc(uib, row, 0);
 			uib->write(uib, entry, row);
+			if (uib->top_idx + row == uib->index)
+				browser->curr = entry;
 			if (++row == uib->rows)
 				break;
 		}
@@ -438,6 +442,78 @@ static void browser__write(struct ui_browser *uib, void *entry, int row)
 	ui_browser__write_nstring(uib, "", uib->width);
 }
 
+static void annotated_data_browser__fold(struct annotated_data_browser *browser,
+					 struct browser_entry *entry,
+					 bool recursive)
+{
+	struct browser_entry *child;
+
+	if (list_empty(&entry->children))
+		return;
+	if (entry->folded && !recursive)
+		return;
+
+	if (recursive) {
+		list_for_each_entry(child, &entry->children, node)
+			annotated_data_browser__fold(browser, child, true);
+	}
+
+	entry->nr_entries = 1;
+	entry->folded = true;
+}
+
+static void annotated_data_browser__unfold(struct annotated_data_browser *browser,
+					   struct browser_entry *entry,
+					   bool recursive)
+{
+	struct browser_entry *child;
+	int nr_entries;
+
+	if (list_empty(&entry->children))
+		return;
+	if (!entry->folded && !recursive)
+		return;
+
+	nr_entries = 1; /* for self */
+	list_for_each_entry(child, &entry->children, node) {
+		if (recursive)
+			annotated_data_browser__unfold(browser, child, true);
+
+		nr_entries += child->nr_entries;
+	}
+
+	entry->nr_entries = nr_entries;
+	entry->folded = false;
+}
+
+static void annotated_data_browser__toggle_fold(struct annotated_data_browser *browser,
+						bool recursive)
+{
+	struct browser_entry *curr = browser->curr;
+	struct browser_entry *parent;
+
+	parent = curr->parent;
+	while (parent) {
+		parent->nr_entries -= curr->nr_entries;
+		parent = parent->parent;
+	}
+	browser->b.nr_entries -= curr->nr_entries;
+
+	if (curr->folded)
+		annotated_data_browser__unfold(browser, curr, recursive);
+	else
+		annotated_data_browser__fold(browser, curr, recursive);
+
+	parent = curr->parent;
+	while (parent) {
+		parent->nr_entries += curr->nr_entries;
+		parent = parent->parent;
+	}
+	browser->b.nr_entries += curr->nr_entries;
+
+	assert(browser->b.nr_entries == count_visible_entries(browser));
+}
+
 static int annotated_data_browser__run(struct annotated_data_browser *browser,
 				       struct evsel *evsel __maybe_unused,
 				       struct hist_browser_timer *hbt)
@@ -462,8 +538,18 @@ static int annotated_data_browser__run(struct annotated_data_browser *browser,
 		"UP/DOWN/PGUP\n"
 		"PGDN/SPACE    Navigate\n"
 		"</>           Move to prev/next symbol\n"
+		"e             Expand/Collapse current entry\n"
+		"E             Expand/Collapse all children of the current\n"
 		"q/ESC/CTRL+C  Exit\n\n");
 			continue;
+		case 'e':
+			annotated_data_browser__toggle_fold(browser,
+							    /*recursive=*/false);
+			break;
+		case 'E':
+			annotated_data_browser__toggle_fold(browser,
+							    /*recursive=*/true);
+			break;
 		case K_LEFT:
 		case '<':
 		case '>':
-- 
2.46.0.76.ge559c4bf1a-goog

[PATCH 3/3] perf annotate-data: Show first-level children by default in TUI

[Namhyung Kim]

Now default is to fold everything but it only shows the name of the
top-level data type which is not very useful.  Instead just expand the
top level entry so that it can show the layout at a higher level.

  Annotate type: 'struct task_struct' (4 samples)
        Percent     Offset       Size  Field
  -      100.00          0       9792  struct task_struct {                           ◆
  +        0.50          0         24      struct thread_info     thread_info;        ▒
           0.00         24          4      unsigned int   __state;                    ▒
           0.00         32          8      void*  stack;                              ▒
  +        0.00         40          4      refcount_t     usage;                      ▒
           0.00         44          4      unsigned int   flags;                      ▒
           0.00         48          4      unsigned int   ptrace;                     ▒
           0.00         52          4      int    on_cpu;                             ▒
  +        0.00         56         16      struct __call_single_node      wake_entry; ▒
           0.00         72          4      unsigned int   wakee_flips;                ▒
           0.00         80          8      long unsigned int      wakee_flip_decay_ts;▒
           0.00         88          8      struct task_struct*    last_wakee;         ▒
           0.00         96          4      int    recent_used_cpu;                    ▒
           0.00        100          4      int    wake_cpu;                           ▒
           0.00        104          4      int    on_rq;                              ▒
           0.00        108          4      int    prio;                               ▒
           0.00        112          4      int    static_prio;                        ▒
           0.00        116          4      int    normal_prio;                        ▒
           0.00        120          4      unsigned int   rt_priority;                ▒
  +        0.00        128        256      struct sched_entity    se;                 ▒
  +        0.00        384         48      struct sched_rt_entity rt;                 ▒
  +        0.00        432        224      struct sched_dl_entity dl;                 ▒
           0.00        656          8      struct sched_class*    sched_class;        ▒
  ...

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/ui/browsers/annotate-data.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/tools/perf/ui/browsers/annotate-data.c b/tools/perf/ui/browsers/annotate-data.c
index a5c5ad63425e..f563a3bb072c 100644
--- a/tools/perf/ui/browsers/annotate-data.c
+++ b/tools/perf/ui/browsers/annotate-data.c
@@ -596,9 +596,17 @@ int hist_entry__annotate_data_tui(struct hist_entry *he, struct evsel *evsel,
 	}
 
 	ret = annotated_data_browser__collect_entries(&browser);
-	if (ret == 0)
-		ret = annotated_data_browser__run(&browser, evsel, hbt);
+	if (ret < 0)
+		goto out;
 
+	/* To get the top and current entry */
+	browser__refresh(&browser.b);
+	/* Show the first-level child entries by default */
+	annotated_data_browser__toggle_fold(&browser, /*recursive=*/false);
+
+	ret = annotated_data_browser__run(&browser, evsel, hbt);
+
+out:
 	annotated_data_browser__delete_entries(&browser);
 
 	return ret;
-- 
2.46.0.76.ge559c4bf1a-goog

Re: [PATCH 0/3] perf annotate-data: Implement folding in TUI browser

[Arnaldo Carvalho de Melo]

On Mon, Aug 12, 2024 at 12:44:44PM -0700, Namhyung Kim wrote:
> Hello,
> 
> I've implemented the folding logic to expand/collapse the current entry
> in the TUI data type browser.  Users can use 'e' or 'E' to toggle the
> entry (with or without children, respectively).
> 
> Ax example output looks like below.
> 
>   Annotate type: 'struct socket' (1 samples)
>         Percent     Offset       Size  Field
>   -      100.00          0        128  struct socket {                                  ◆
>            0.00          0          4      socket_state   state;                        ▒
>            0.00          4          2      short int      type;                         ▒
>            0.00          8          8      long unsigned int      flags;                ▒
>            0.00         16          8      struct file*   file;                         ▒
>          100.00         24          8      struct sock*   sk;                           ▒
>            0.00         32          8      struct proto_ops*      ops;                  ▒
>   -        0.00         64         64      struct socket_wq       wq {                  ▒
>   -        0.00         64         24          wait_queue_head_t  wait {                ▒
>   +        0.00         64          4              spinlock_t     lock;                 ▒
>   -        0.00         72         16              struct list_head       head {        ▒
>            0.00         72          8                  struct list_head*  next;         ▒
>            0.00         80          8                  struct list_head*  prev;         ▒
>                                                    };                                   ▒
>                                                };                                       ▒
>            0.00         88          8          struct fasync_struct*      fasync_list;  ▒
>            0.00         96          8          long unsigned int  flags;                ▒
>   +        0.00        104         16          struct callback_head       rcu;          ▒
>                                            };                                           ▒
>                                        };                                               ▒
> 
> It hides the detail of spinlock_t and struct callback_head.

Thanks, useful feature! All tested and applied.

- Arnaldo