From: Michal Sojka <sojkam1@fel.cvut.cz>
Date: Thu, 26 Nov 2009 20:35:56 +0000 (+0100)
Subject: disk_bfq: Make error messages meaninful
X-Git-Url: http://rtime.felk.cvut.cz/gitweb/frescor/frsh.git/commitdiff_plain/d961c59db94a77ed2ab0e4f4b1f3c06cc788923c

disk_bfq: Make error messages meaninful
---

diff --git a/resources/disk_bfq/mngr/diskbfq_mngr.c b/resources/disk_bfq/mngr/diskbfq_mngr.c
index 8b66a76..da32e7f 100644
--- a/resources/disk_bfq/mngr/diskbfq_mngr.c
+++ b/resources/disk_bfq/mngr/diskbfq_mngr.c
@@ -232,13 +232,13 @@ err_usage:
 		 SYSFS_BFQ_SCHED_PATH,
 		 disk_name);
 	if (!(fd = fopen(path, "r+")))
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "fopen(%s)", path);
 
 	ret = fscanf(fd, "%128[^\n]", scheduler);
 	if (ret == 0 || ret == EOF)
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "fscanf: %s", path);
 	if (!strstr(scheduler, SYSFS_BFQ_NAME))
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "bfq not available in kernel");
 
 	/**
 	 * Now check if BFQ is the default I/O scheduler
@@ -250,7 +250,7 @@ err_usage:
 		if (ret && ret != EOF)
 			ret = fflush(fd);
 		if (ret == 0 || ret == EOF)
-			error(1, errno, "frm_generic_run");
+			error(1, errno, "cannot activate bfq scheduler");
 	}
 	fclose(fd);
 
@@ -258,25 +258,26 @@ err_usage:
 		 SYSFS_BFQ_BUDGET_PATH,
 		 disk_name);
 	if (!(fd = fopen(path, "r+")))
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "fopen(%s)", path);
 
 	ret = fprintf(fd, "256");
 	if (ret == 0)
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "fprintf: %s", path);
 
 	rewind(fd);
 	ret = fscanf(fd, "%d", &disk.budget);
 	if (ret == 0 || ret == EOF)
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "fscanf: %s", path);
 	fclose(fd);
 
 	/**
 	 * Estimate the disk throughput in order to achieve
 	 *  effective weight assignement during runtime.
 	 **/
+	printf("Throughput estimation...\n");
 	disk.throughput = estimate_throughput(disk_dev, readers);
 	if (disk.throughput < 0.0)
-		error(1, errno, "frm_generic_run");
+		error(1, errno, "throughput estimation error");
 
 	fprintf(stdout, "disk name: %s\n"
 		"scheduler: %s\n"
@@ -289,7 +290,7 @@ err_usage:
         fres_block_register_disk_sched();
 
 	ret = frm_register_and_run(orb, &frm);
-	if (ret) error(1, errno, "frm_generic_run");
+	if (ret) error(1, errno, "frm_register_and_run");
 	
 	return 0;
 }
diff --git a/resources/disk_bfq/mngr/diskbfq_th.c b/resources/disk_bfq/mngr/diskbfq_th.c
index 7bb3516..4fabc6a 100644
--- a/resources/disk_bfq/mngr/diskbfq_th.c
+++ b/resources/disk_bfq/mngr/diskbfq_th.c
@@ -192,6 +192,8 @@ double estimate_throughput(char *device, int streamers)
 
 	if (!error)
 		throughput = calc_throughput(ddata, &begin, &end);
+	else
+		errno = error;
 	free(ddata);
 
 err: