trace: add trace directory configuration parameter

Trace library exposes --trace-dir EAL parameter to configure
directory where traces will be generated.

Signed-off-by: Sunil Kumar Kori <skori@marvell.com>
Acked-by: David Marchand <david.marchand@redhat.com>

doc/guides/linux_gsg/eal_args.include.rst

@@ -152,6 +152,17 @@ Debugging options
 
     Can be specified multiple times up to 32 times.
 
+*   ``--trace-dir=<directory path>``
+
+    Specify trace directory for trace output. For example:
+
+    Configuring ``/tmp/`` as a trace output directory::
+
+        --trace-dir=/tmp
+
+    By default, trace output will created at ``home`` directory and parameter
+    must be specified once only.
+
 Other options
 ~~~~~~~~~~~~~
 

lib/librte_eal/common/eal_common_options.c

@@ -69,6 +69,7 @@ eal_long_options[] = {
 	{OPT_LCORES,            1, NULL, OPT_LCORES_NUM           },
 	{OPT_LOG_LEVEL,         1, NULL, OPT_LOG_LEVEL_NUM        },
 	{OPT_TRACE,             1, NULL, OPT_TRACE_NUM            },
+	{OPT_TRACE_DIR,         1, NULL, OPT_TRACE_DIR_NUM        },
 	{OPT_MASTER_LCORE,      1, NULL, OPT_MASTER_LCORE_NUM     },
 	{OPT_MBUF_POOL_OPS_NAME, 1, NULL, OPT_MBUF_POOL_OPS_NAME_NUM},
 	{OPT_NO_HPET,           0, NULL, OPT_NO_HPET_NUM          },
@@ -1430,6 +1431,15 @@ eal_parse_common_option(int opt, const char *optarg,
 		break;
 	}
 
+	case OPT_TRACE_DIR_NUM: {
+		if (eal_trace_dir_args_save(optarg) < 0) {
+			RTE_LOG(ERR, EAL, "invalid parameters for --"
+				OPT_TRACE_DIR "\n");
+			return -1;
+		}
+		break;
+	}
+
 	case OPT_LCORES_NUM:
 		if (eal_parse_lcores(optarg) < 0) {
 			RTE_LOG(ERR, EAL, "invalid parameter for --"
@@ -1709,6 +1719,11 @@ eal_common_usage(void)
 	       "                      Enable trace based on regular expression trace name.\n"
 	       "                      By default, the trace is disabled.\n"
 	       "		      User must specify this option to enable trace.\n"
+	       "  --"OPT_TRACE_DIR"=<directory path>\n"
+	       "                      Specify trace directory for trace output.\n"
+	       "                      By default, trace output will created at\n"
+	       "                      $HOME directory and parameter must be\n"
+	       "                      specified once only.\n"
 	       "  -v                  Display version information on startup\n"
 	       "  -h, --help          This help\n"
 	       "  --"OPT_IN_MEMORY"   Operate entirely in memory. This will\n"

lib/librte_eal/common/eal_common_trace_utils.c

@@ -118,6 +118,22 @@ trace_session_name_generate(char *trace_dir)
 	return -rte_errno;
 }
 
+static int
+trace_dir_update(const char *str)
+{
+	struct trace *trace = trace_obj_get();
+	int rc, remaining;
+
+	remaining = sizeof(trace->dir) - trace->dir_offset;
+	rc = rte_strscpy(&trace->dir[0] + trace->dir_offset, str, remaining);
+	if (rc < 0)
+		goto fail;
+
+	trace->dir_offset += rc;
+fail:
+	return rc;
+}
+
 int
 eal_trace_args_save(const char *optarg)
 {
@@ -177,6 +193,37 @@ trace_args_apply(const char *arg)
 	return 0;
 }
 
+int
+eal_trace_dir_args_save(char const *optarg)
+{
+	struct trace *trace = trace_obj_get();
+	uint32_t size = sizeof(trace->dir);
+	char *dir_path = NULL;
+	int rc;
+
+	if (optarg == NULL) {
+		trace_err("no optarg is passed");
+		return -EINVAL;
+	}
+
+	if (strlen(optarg) >= size) {
+		trace_err("input string is too big");
+		return -ENAMETOOLONG;
+	}
+
+	dir_path = (char *)calloc(1, size);
+	if (dir_path == NULL) {
+		trace_err("fail to allocate memory");
+		return -ENOMEM;
+	}
+
+	sprintf(dir_path, "%s/", optarg);
+	rc = trace_dir_update(dir_path);
+
+	free(dir_path);
+	return rc;
+}
+
 int
 trace_epoch_time_save(void)
 {
@@ -247,6 +294,10 @@ trace_mkdir(void)
 			return rc;
 		}
 
+		rc = trace_dir_update(dir_path);
+		free(dir_path);
+		if (rc < 0)
+			return rc;
 	}
 
 	/* Create the path if it t exist, no "mkdir -p" available here */
@@ -258,6 +309,9 @@ trace_mkdir(void)
 	}
 
 	rc = trace_session_name_generate(session);
+	if (rc < 0)
+		return rc;
+	rc = trace_dir_update(session);
 	if (rc < 0)
 		return rc;
 

lib/librte_eal/common/eal_options.h

@@ -35,6 +35,8 @@ enum {
 	OPT_LOG_LEVEL_NUM,
 #define OPT_TRACE             "trace"
 	OPT_TRACE_NUM,
+#define OPT_TRACE_DIR         "trace-dir"
+	OPT_TRACE_DIR_NUM,
 #define OPT_MASTER_LCORE      "master-lcore"
 	OPT_MASTER_LCORE_NUM,
 #define OPT_MBUF_POOL_OPS_NAME "mbuf-pool-ops-name"

lib/librte_eal/common/eal_trace.h

@@ -112,5 +112,6 @@ int eal_trace_init(void);
 void eal_trace_fini(void);
 int eal_trace_args_save(const char *optarg);
 void eal_trace_args_free(void);
+int eal_trace_dir_args_save(const char *optarg);
 
 #endif /* __EAL_TRACE_H */