thread: Change direct accesses to poller outside lib/thread to helper functions

Most accesses to the struct spdk_poller outside lib/thread have been
done via functions but a few direct accesses remain.

Change these to indirect accesses by addinng a few helper functions
as SPDK internal APIs.

Add spdk_poller_get_name() to get the name of the poller.

Remove spdk_poller_state_str() and add spdk_poller_get_state_str().
Exposing enum spdk_poller_state outside lib/thread is not really
necessary.

This removal requires us to update major SO version.

Add spdk_poller_get_period_ticks() to get the period ticks of the
poller.

Add struct spdk_poller_stats and spdk_poller_get_stats() to get
the stats of the poller.

The next patch will move the definition of struct spdk_poller and
enum spdk_poller_state from include/spdk_internal/thread.h to
lib/thread/thread.c.

Signed-off-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Change-Id: Id597dae074a15fcd8af09fd9d416a22ce2f403c3
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/7798
Community-CI: Broadcom CI
Community-CI: Mellanox Build Bot
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
Reviewed-by: Aleksey Marchuk <alexeymar@mellanox.com>

include/spdk_internal/thread.h

@@ -81,6 +81,11 @@ struct spdk_poller {
 	char				name[SPDK_MAX_POLLER_NAME_LEN + 1];
 };
 
+struct spdk_poller_stats {
+	uint64_t	run_count;
+	uint64_t	busy_count;
+};
+
 enum spdk_thread_state {
 	/* The thread is pocessing poller and message by spdk_thread_poll(). */
 	SPDK_THREAD_STATE_RUNNING,
@@ -138,7 +143,10 @@ struct spdk_thread {
 	uint8_t				ctx[0];
 };
 
-const char *spdk_poller_state_str(enum spdk_poller_state state);
+const char *spdk_poller_get_name(struct spdk_poller *poller);
+const char *spdk_poller_get_state_str(struct spdk_poller *poller);
+uint64_t spdk_poller_get_period_ticks(struct spdk_poller *poller);
+void spdk_poller_get_stats(struct spdk_poller *poller, struct spdk_poller_stats *stats);
 
 const char *spdk_io_device_get_name(struct io_device *dev);
 

lib/event/app_rpc.c

@@ -250,13 +250,19 @@ SPDK_RPC_REGISTER("thread_get_stats", rpc_thread_get_stats, SPDK_RPC_RUNTIME)
 static void
 rpc_get_poller(struct spdk_poller *poller, struct spdk_json_write_ctx *w)
 {
+	struct spdk_poller_stats stats;
+	uint64_t period_ticks;
+
+	period_ticks = spdk_poller_get_period_ticks(poller);
+	spdk_poller_get_stats(poller, &stats);
+
 	spdk_json_write_object_begin(w);
-	spdk_json_write_named_string(w, "name", poller->name);
+	spdk_json_write_named_string(w, "name", spdk_poller_get_name(poller));
-	spdk_json_write_named_string(w, "state", spdk_poller_state_str(poller->state));
+	spdk_json_write_named_string(w, "state", spdk_poller_get_state_str(poller));
-	spdk_json_write_named_uint64(w, "run_count", poller->run_count);
+	spdk_json_write_named_uint64(w, "run_count", stats.run_count);
-	spdk_json_write_named_uint64(w, "busy_count", poller->busy_count);
+	spdk_json_write_named_uint64(w, "busy_count", stats.busy_count);
-	if (poller->period_ticks) {
+	if (period_ticks) {
-		spdk_json_write_named_uint64(w, "period_ticks", poller->period_ticks);
+		spdk_json_write_named_uint64(w, "period_ticks", period_ticks);
 	}
 	spdk_json_write_object_end(w);
 }

lib/thread/Makefile

@@ -34,8 +34,8 @@
 SPDK_ROOT_DIR := $(abspath $(CURDIR)/../..)
 include $(SPDK_ROOT_DIR)/mk/spdk.common.mk
 
-SO_VER := 5
+SO_VER := 6
-SO_MINOR := 1
+SO_MINOR := 0
 
 C_SRCS = thread.c
 LIBNAME = thread

lib/thread/spdk_thread.map

@@ -57,7 +57,10 @@
 	spdk_interrupt_mode_is_enabled;
 
 	# internal functions in spdk_internal/thread.h
-	spdk_poller_state_str;
+	spdk_poller_get_name;
+	spdk_poller_get_state_str;
+	spdk_poller_get_period_ticks;
+	spdk_poller_get_stats;
 	spdk_io_device_get_name;
 	spdk_thread_get_first_active_poller;
 	spdk_thread_get_next_active_poller;

lib/thread/thread.c

@@ -1491,9 +1491,15 @@ spdk_poller_resume(struct spdk_poller *poller)
 }
 
 const char *
-spdk_poller_state_str(enum spdk_poller_state state)
+spdk_poller_get_name(struct spdk_poller *poller)
 {
-	switch (state) {
+	return poller->name;
+}
+
+const char *
+spdk_poller_get_state_str(struct spdk_poller *poller)
+{
+	switch (poller->state) {
 	case SPDK_POLLER_STATE_WAITING:
 		return "waiting";
 	case SPDK_POLLER_STATE_RUNNING:
@@ -1509,6 +1515,19 @@ spdk_poller_state_str(enum spdk_poller_state state)
 	}
 }
 
+uint64_t
+spdk_poller_get_period_ticks(struct spdk_poller *poller)
+{
+	return poller->period_ticks;
+}
+
+void
+spdk_poller_get_stats(struct spdk_poller *poller, struct spdk_poller_stats *stats)
+{
+	stats->run_count = poller->run_count;
+	stats->busy_count = poller->busy_count;
+}
+
 struct spdk_poller *
 spdk_thread_get_first_active_poller(struct spdk_thread *thread)
 {