[PATCH 02/14] perf c2c: add function view browser skeleton

[Jiebin Sun]

Add c2c-function.c with a stub perf_c2c__browse_function_view() entry
point and register it in the build system. Declare the function
prototype in c2c.h.

This lays the groundwork for the function-level cacheline sharing
analysis browser that will be implemented in subsequent patches.

Signed-off-by: Jiebin Sun <jiebin.sun@xxxxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: James Clark <james.clark@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Falcon <thomas.falcon@xxxxxxxxx>
Reviewed-by: Tianyou Li <tianyou.li@xxxxxxxxx>
Reviewed-by: Wangyang Guo <wangyang.guo@xxxxxxxxx>
---
 tools/perf/c2c.h                      |  1 +
 tools/perf/ui/browsers/Build          |  1 +
 tools/perf/ui/browsers/c2c-function.c | 44 +++++++++++++++++++++++++++
 3 files changed, 46 insertions(+)
 create mode 100644 tools/perf/ui/browsers/c2c-function.c

diff --git a/tools/perf/c2c.h b/tools/perf/c2c.h
index 3e974dd1d7ee..385709536a1a 100644
--- a/tools/perf/c2c.h
+++ b/tools/perf/c2c.h
@@ -134,6 +134,7 @@ bool fmt_equal(struct perf_hpp_fmt *a, struct perf_hpp_fmt *b);
 
 #ifdef HAVE_SLANG_SUPPORT
 int perf_c2c__browse_cacheline(struct hist_entry *he);
+int perf_c2c__browse_function_view(struct hists *hists);
 #endif
 
 #endif /* _PERF_C2C_H_ */
diff --git a/tools/perf/ui/browsers/Build b/tools/perf/ui/browsers/Build
index a07489e44765..ae67a2161f7d 100644
--- a/tools/perf/ui/browsers/Build
+++ b/tools/perf/ui/browsers/Build
@@ -5,3 +5,4 @@ perf-ui-y += map.o
 perf-ui-y += scripts.o
 perf-ui-y += header.o
 perf-ui-y += res_sample.o
+perf-ui-y += c2c-function.o
diff --git a/tools/perf/ui/browsers/c2c-function.c b/tools/perf/ui/browsers/c2c-function.c
new file mode 100644
index 000000000000..040266288be3
--- /dev/null
+++ b/tools/perf/ui/browsers/c2c-function.c
@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * C2C Function Browser - function-level cacheline sharing analysis
+ *
+ * Planned UI: 3-level hierarchy showing which functions share cachelines (not implemented yet):
+ *   Level 1: Primary functions sorted by Cycles % (estimated load cycles)
+ *   Level 2: Other functions sharing cachelines with the level-1 function
+ *   Level 3: Specific shared cachelines between each pair of functions
+ *
+ * Uses c2c_hist_entry->hists to build the hierarchy without adding any
+ * per-entry state to the existing c2c data structures.
+ */
+
+#include <errno.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+#include <linux/list.h>
+#include <linux/rbtree.h>
+#include <linux/zalloc.h>
+
+#include "../browser.h"
+#include "../helpline.h"
+#include "../keysyms.h"
+#include "../libslang.h"
+#include "../ui.h"
+#include "../../util/addr_location.h"
+#include "../../util/cacheline.h"
+#include "../../util/debug.h"
+#include "../../util/hist.h"
+#include "../../util/map.h"
+#include "../../util/mem-events.h"
+#include "../../util/mem-info.h"
+#include "../../util/sort.h"
+#include "../../util/symbol.h"
+#include "../../util/thread.h"
+#include "../../c2c.h"
+#include "hists.h"
+
+int perf_c2c__browse_function_view(struct hists *hists __maybe_unused)
+{
+	ui__warning("C2C function view is not implemented yet.\n");
+	return -ENOSYS;
+}
-- 
2.52.0