From 70e0c3166fdb8048b1e7f84be2371fc60af04f87 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Tue, 4 Oct 2011 09:18:30 +0200
Subject: [PATCH] server: idle loop support

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 client.c |  2 +-
 fio.c    |  4 ++--
 server.c | 21 +++++++++++++--------
 server.h |  2 +-
 4 files changed, 17 insertions(+), 12 deletions(-)

diff --git a/client.c b/client.c
index b82c322c..464dce64 100644
--- a/client.c
+++ b/client.c
@@ -379,7 +379,7 @@ static int handle_client(struct fio_client *client)
 	struct fio_net_cmd *cmd;
 	int done = 0;
 
-	while ((cmd = fio_net_recv_cmd(client->fd)) != NULL) {
+	while ((cmd = fio_net_recv_cmd(client->fd, 1)) != NULL) {
 		dprint(FD_NET, "%s: got cmd op %d\n", client->hostname,
 							cmd->opcode);
 
diff --git a/fio.c b/fio.c
index d1faacae..3e4dbb74 100644
--- a/fio.c
+++ b/fio.c
@@ -1696,8 +1696,8 @@ static void run_threads(void)
 
 		if (is_backend)
 			fio_server_idle_loop();
-
-		usleep(10000);
+		else
+			usleep(10000);
 	}
 
 	update_io_ticks();
diff --git a/server.c b/server.c
index 938f58bb..a48842e6 100644
--- a/server.c
+++ b/server.c
@@ -111,7 +111,7 @@ static int verify_convert_cmd(struct fio_net_cmd *cmd)
 /*
  * Read (and defragment, if necessary) incoming commands
  */
-struct fio_net_cmd *fio_net_recv_cmd(int sk)
+struct fio_net_cmd *fio_net_recv_cmd(int sk, int block)
 {
 	struct fio_net_cmd cmd, *cmdret = NULL;
 	size_t cmd_size = 0, pdu_offset = 0;
@@ -126,14 +126,19 @@ struct fio_net_cmd *fio_net_recv_cmd(int sk)
 		pfd.events = POLLIN;
 		ret = 0;
 		do {
-			ret = poll(&pfd, 1, 100);
+			int timeo = block ? 100 : 10;
+
+			ret = poll(&pfd, 1, timeo);
 			if (ret < 0) {
 				if (errno == EINTR)
 					break;
 				log_err("fio: poll: %s\n", strerror(errno));
 				break;
-			} else if (!ret)
+			} else if (!ret) {
+				if (!block)
+					return NULL;
 				continue;
+			}
 
 			if (pfd.revents & POLLIN)
 				break;
@@ -141,7 +146,7 @@ struct fio_net_cmd *fio_net_recv_cmd(int sk)
 				ret = 1;
 				break;
 			}
-		} while (ret >= 0);
+		} while (ret >= 0 && block);
 
 		if (ret < 0)
 			break;
@@ -311,14 +316,14 @@ static int handle_command(struct fio_net_cmd *cmd)
 	return ret;
 }
 
-static int handle_connection(int sk)
+static int handle_connection(int sk, int block)
 {
 	struct fio_net_cmd *cmd = NULL;
 	int ret = 0;
 
 	/* read forever */
 	while (!exit_backend) {
-		cmd = fio_net_recv_cmd(sk);
+		cmd = fio_net_recv_cmd(sk, block);
 		if (!cmd) {
 			ret = -1;
 			break;
@@ -341,7 +346,7 @@ static int handle_connection(int sk)
 void fio_server_idle_loop(void)
 {
 	if (server_fd != -1)
-		handle_connection(server_fd);
+		handle_connection(server_fd, 0);
 }
 
 static int accept_loop(int listen_sk)
@@ -384,7 +389,7 @@ again:
 
 	server_fd = sk;
 
-	exitval = handle_connection(sk);
+	exitval = handle_connection(sk, 1);
 
 	server_fd = -1;
 	close(sk);
diff --git a/server.h b/server.h
index 4783238b..494c326e 100644
--- a/server.h
+++ b/server.h
@@ -80,7 +80,7 @@ extern void fio_client_add(const char *);
 extern int fio_recv_data(int sk, void *p, unsigned int len);
 extern int fio_send_data(int sk, const void *p, unsigned int len);
 extern void fio_net_cmd_crc(struct fio_net_cmd *);
-extern struct fio_net_cmd *fio_net_recv_cmd(int sk);
+extern struct fio_net_cmd *fio_net_recv_cmd(int sk, int block);
 
 extern int exit_backend;
 extern int fio_net_port;
-- 
2.25.1