trace: add trace configuration parameter

Trace library exposes --trace EAL parameter to enable trace points.

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

@@ -136,6 +136,22 @@ Debugging options
 
     Can be specified multiple times.
 
+*   ``--trace=<regex-match>``
+
+    Enable trace based on regular expression trace name. By default, the trace is
+    disabled. User must specify this option to enable trace.
+    For example:
+
+    Global trace configuration for EAL only::
+
+        --trace=eal
+
+    Global trace configuration for ALL the components::
+
+        --trace=.*
+
+    Can be specified multiple times up to 32 times.
+
 Other options
 ~~~~~~~~~~~~~
 

lib/librte_eal/common/eal_common_options.c

@@ -34,6 +34,7 @@
 #include "eal_options.h"
 #include "eal_filesystem.h"
 #include "eal_private.h"
+#include "eal_trace.h"
 
 #define BITS_PER_HEX 4
 #define LCORE_OPT_LST 1
@@ -67,6 +68,7 @@ eal_long_options[] = {
 	{OPT_IOVA_MODE,	        1, NULL, OPT_IOVA_MODE_NUM        },
 	{OPT_LCORES,            1, NULL, OPT_LCORES_NUM           },
 	{OPT_LOG_LEVEL,         1, NULL, OPT_LOG_LEVEL_NUM        },
+	{OPT_TRACE,             1, NULL, OPT_TRACE_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          },
@@ -1418,6 +1420,16 @@ eal_parse_common_option(int opt, const char *optarg,
 		}
 		break;
 	}
+
+	case OPT_TRACE_NUM: {
+		if (eal_trace_args_save(optarg) < 0) {
+			RTE_LOG(ERR, EAL, "invalid parameters for --"
+				OPT_TRACE "\n");
+			return -1;
+		}
+		break;
+	}
+
 	case OPT_LCORES_NUM:
 		if (eal_parse_lcores(optarg) < 0) {
 			RTE_LOG(ERR, EAL, "invalid parameter for --"
@@ -1693,6 +1705,10 @@ eal_common_usage(void)
 	       "  --"OPT_LOG_LEVEL"=<int>   Set global log level\n"
 	       "  --"OPT_LOG_LEVEL"=<type-match>:<int>\n"
 	       "                      Set specific log level\n"
+	       "  --"OPT_TRACE"=<regex-match>\n"
+	       "                      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"
 	       "  -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.c

@@ -38,6 +38,8 @@ trace_list_head_get(void)
 int
 eal_trace_init(void)
 {
+	uint8_t i;
+
 	/* Trace memory should start with 8B aligned for natural alignment */
 	RTE_BUILD_BUG_ON((offsetof(struct __rte_trace_header, mem) % 8) != 0);
 
@@ -47,6 +49,9 @@ eal_trace_init(void)
 		goto fail;
 	}
 
+	if (trace.args.nb_args)
+		trace.status = true;
+
 	if (!rte_trace_is_enabled())
 		return 0;
 
@@ -73,6 +78,10 @@ eal_trace_init(void)
 	if (trace_epoch_time_save() < 0)
 		goto fail;
 
+	/* Apply global configurations */
+	for (i = 0; i < trace.args.nb_args; i++)
+		trace_args_apply(trace.args.args[i]);
+
 	rte_trace_mode_set(trace.mode);
 
 	return 0;
@@ -91,6 +100,7 @@ eal_trace_fini(void)
 		return;
 	trace_mem_per_thread_free();
 	trace_metadata_destroy();
+	eal_trace_args_free();
 }
 
 bool

lib/librte_eal/common/eal_common_trace_utils.c

@@ -118,6 +118,65 @@ fail:
 	return -rte_errno;
 }
 
+int
+eal_trace_args_save(const char *optarg)
+{
+	struct trace *trace = trace_obj_get();
+	char *trace_args;
+	uint8_t nb_args;
+
+	nb_args = trace->args.nb_args;
+
+	if (nb_args >= TRACE_MAX_ARGS) {
+		trace_err("ignoring trace %s as limit exceeds", optarg);
+		return 0;
+	}
+
+	trace_args = calloc(1, (strlen(optarg) + 1));
+	if (trace_args == NULL) {
+		trace_err("fail to allocate memory for %s", optarg);
+		return -ENOMEM;
+	}
+
+	memcpy(trace_args, optarg, strlen(optarg));
+	trace->args.args[nb_args++] = trace_args;
+	trace->args.nb_args = nb_args;
+	return 0;
+}
+
+void
+eal_trace_args_free(void)
+{
+	struct trace *trace = trace_obj_get();
+	int i;
+
+	for (i = 0; i < trace->args.nb_args; i++) {
+		if (trace->args.args[i]) {
+			free((void *)trace->args.args[i]);
+			trace->args.args[i] = NULL;
+		}
+	}
+}
+
+int
+trace_args_apply(const char *arg)
+{
+	char *str;
+
+	str = strdup(arg);
+	if (str == NULL)
+		return -1;
+
+	if (rte_trace_regexp(str, true) < 0) {
+		trace_err("cannot enable trace for %s", str);
+		free(str);
+		return -1;
+	}
+
+	free(str);
+	return 0;
+}
+
 int
 trace_epoch_time_save(void)
 {

lib/librte_eal/common/eal_options.h

@@ -33,6 +33,8 @@ enum {
 	OPT_LCORES_NUM,
 #define OPT_LOG_LEVEL         "log-level"
 	OPT_LOG_LEVEL_NUM,
+#define OPT_TRACE             "trace"
+	OPT_TRACE_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

@@ -27,7 +27,7 @@
 #define TRACE_CTF_FIELD_SIZE 384
 #define TRACE_POINT_NAME_SIZE 64
 #define TRACE_CTF_MAGIC 0xC1FC1FC1
-
+#define TRACE_MAX_ARGS	32
 
 struct trace_point {
 	STAILQ_ENTRY(trace_point) next;
@@ -46,6 +46,11 @@ struct thread_mem_meta {
 	enum trace_area_e area;
 };
 
+struct trace_args {
+	uint8_t nb_args;
+	char *args[TRACE_MAX_ARGS];
+};
+
 struct trace {
 	char dir[PATH_MAX];
 	int dir_offset;
@@ -54,6 +59,7 @@ struct trace {
 	enum rte_trace_mode mode;
 	rte_uuid_t uuid;
 	uint32_t buff_len;
+	struct trace_args args;
 	uint32_t nb_trace_points;
 	uint32_t nb_trace_mem_list;
 	struct thread_mem_meta *lcore_meta;
@@ -92,6 +98,7 @@ struct trace_point_head *trace_list_head_get(void);
 /* Util functions */
 const char *trace_mode_to_string(enum rte_trace_mode mode);
 const char *trace_area_to_string(enum trace_area_e area);
+int trace_args_apply(const char *arg);
 bool trace_has_duplicate_entry(void);
 void trace_uuid_generate(void);
 int trace_metadata_create(void);
@@ -103,5 +110,7 @@ void trace_mem_per_thread_free(void);
 /* EAL interface */
 int eal_trace_init(void);
 void eal_trace_fini(void);
+int eal_trace_args_save(const char *optarg);
+void eal_trace_args_free(void);
 
 #endif /* __EAL_TRACE_H */