perf kwork: Add irq kwork record support

Record interrupt events irq:irq_handler_entry & irq_handler_exit

Test cases:

 # perf kwork record -o perf_kwork.date -- sleep 1
  [ perf record: Woken up 0 times to write data ]
  [ perf record: Captured and wrote 0.556 MB perf_kwork.date ]
  #
  # perf evlist -i perf_kwork.date
  irq:irq_handler_entry
  irq:irq_handler_exit
  dummy:HG
  # Tip: use 'perf evlist --trace-fields' to show fields for tracepoint events
  #

Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220709015033.38326-3-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-kwork.txt

@@ -32,7 +32,7 @@ OPTIONS
 
 -k::
 --kwork::
-	List of kwork to profile
+	List of kwork to profile (irq, etc)
 
 -v::
 --verbose::

tools/perf/builtin-kwork.c

@@ -25,7 +25,20 @@
 #include <linux/time64.h>
 #include <linux/zalloc.h>
 
+const struct evsel_str_handler irq_tp_handlers[] = {
+	{ "irq:irq_handler_entry", NULL, },
+	{ "irq:irq_handler_exit",  NULL, },
+};
+
+static struct kwork_class kwork_irq = {
+	.name           = "irq",
+	.type           = KWORK_CLASS_IRQ,
+	.nr_tracepoints = 2,
+	.tp_handlers    = irq_tp_handlers,
+};
+
 static struct kwork_class *kwork_class_supported_list[KWORK_CLASS_MAX] = {
+	[KWORK_CLASS_IRQ]       = &kwork_irq,
 };
 
 static void setup_event_list(struct perf_kwork *kwork,
@@ -133,7 +146,7 @@ int cmd_kwork(int argc, const char **argv)
 	OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
 		    "dump raw trace in ASCII"),
 	OPT_STRING('k', "kwork", &kwork.event_list_str, "kwork",
-		   "list of kwork to profile"),
+		   "list of kwork to profile (irq, etc)"),
 	OPT_BOOLEAN('f', "force", &kwork.force, "don't complain, do it"),
 	OPT_END()
 	};

tools/perf/util/kwork.h

@@ -13,6 +13,7 @@
 #include <linux/bitmap.h>
 
 enum kwork_class_type {
+	KWORK_CLASS_IRQ,
 	KWORK_CLASS_MAX,
 };