[dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[David Marchand]

Following recent increase of an internal array that was limiting CTF event
descriptions, I had a second look at the code.
All of this is slow path, so I see no reason in keeping this limitation
and we can go with dynamic allocations.

While at it, I tweaked the metadata file output.

I consider this -rc2 material.

-- 
David Marchand

David Marchand (3):
  trace: fixup CTF event description at registration
  trace: remove size limit on CTF event description
  trace: make CTF metadata prettier

 lib/librte_eal/common/eal_common_trace.c     |  44 ++---
 lib/librte_eal/common/eal_common_trace_ctf.c | 164 +++++--------------
 lib/librte_eal/common/eal_trace.h            |   4 +-
 3 files changed, 67 insertions(+), 145 deletions(-)

-- 
2.23.0

[dpdk-dev] [PATCH 1/3] trace: fixup CTF event description at registration

[David Marchand]

CTF event description is currently built by appending all fields in a
single string at trace point registration.
When dumping the metadata, this string is split again and inspected to
fixup reserved keywords and special tokens like "." or "->".

Move this fixup per field at trace point registration time so that there
is no need for inspecting / string parsing when dumping metadata.
Use dynamic allocations to remove an artificial size limit on the CTF
event description manipulations.

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace.c     |   5 +
 lib/librte_eal/common/eal_common_trace_ctf.c | 159 +++++--------------
 lib/librte_eal/common/eal_trace.h            |   1 +
 3 files changed, 46 insertions(+), 119 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index b6da5537fe..80b458edb6 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -432,11 +432,16 @@ __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 	char *field = RTE_PER_LCORE(ctf_field);
 	int count = RTE_PER_LCORE(ctf_count);
 	size_t size;
+	char *fixup;
 	int rc;
 
 	size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
 	RTE_PER_LCORE(trace_point_sz) += sz;
+	fixup = trace_metadata_fixup_field(in);
+	if (fixup != NULL)
+		in = fixup;
 	rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
+	free(fixup);
 	if (rc <= 0 || (size_t)rc >= size) {
 		RTE_PER_LCORE(trace_point_sz) = 0;
 		trace_crit("CTF field is too long");
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index 9dc91df0fb..bc86432902 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -220,131 +220,12 @@ meta_stream_emit(char **meta, int *offset)
 	return meta_copy(meta, offset, str, rc);
 }
 
-static void
-string_fixed_replace(char *input, const char *search, const char *replace)
-{
-	char *found;
-	size_t len;
-
-	found = strstr(input, search);
-	if (found == NULL)
-		return;
-
-	if (strlen(found) != strlen(search))
-		return;
-
-	len = strlen(replace);
-	memcpy(found, replace, len);
-	found[len] = '\0';
-}
-
-static void
-ctf_fixup_align(char *str)
-{
-	string_fixed_replace(str, "align", "_align");
-}
-
-static void
-ctf_fixup_arrow_deref(char *str)
-{
-	const char *replace = "_";
-	const char *search = "->";
-	char *found;
-	size_t len;
-
-	found = strstr(str, search);
-	if (found == NULL)
-		return;
-
-	do {
-		memcpy(found, replace, strlen(replace));
-		len = strlen(found + 2);
-		memcpy(found + 1, found + 2, len);
-		found[len + 1] = '\0';
-		found = strstr(str, search);
-	} while (found != NULL);
-}
-
-static void
-ctf_fixup_dot_deref(char *str)
-{
-	const char *replace = "_";
-	const char *search = ".";
-	char *found;
-	size_t len;
-
-	found = strstr(str, search);
-	if (found == NULL)
-		return;
-
-	len = strlen(replace);
-	do {
-		memcpy(found, replace, len);
-		found = strstr(str, search);
-	} while (found != NULL);
-}
-
-static void
-ctf_fixup_event(char *str)
-{
-	string_fixed_replace(str, "event", "_event");
-}
-
-static int
-ctf_fixup_keyword(char *str)
-{
-	char dup_str[TRACE_CTF_FIELD_SIZE];
-	char input[TRACE_CTF_FIELD_SIZE];
-	const char *delim = ";";
-	char *from;
-	int len;
-
-	if (str == NULL)
-		return 0;
-
-	len = strlen(str);
-	if (len >= TRACE_CTF_FIELD_SIZE) {
-		trace_err("ctf_field reached its maximum limit");
-		return -EMSGSIZE;
-	}
-
-	/* Create duplicate string */
-	strcpy(dup_str, str);
-
-	len = 0;
-	from = strtok(dup_str, delim);
-	while (from != NULL) {
-		strcpy(input, from);
-		ctf_fixup_align(input);
-		ctf_fixup_dot_deref(input);
-		ctf_fixup_arrow_deref(input);
-		ctf_fixup_event(input);
-
-		strcpy(&input[strlen(input)], delim);
-		if ((len + strlen(input)) >= TRACE_CTF_FIELD_SIZE) {
-			trace_err("ctf_field reached its maximum limit");
-			return -EMSGSIZE;
-		}
-
-		strcpy(str + len, input);
-		len += strlen(input);
-		from = strtok(NULL, delim);
-	}
-
-	return 0;
-}
-
 static int
 meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 {
 	char *str = NULL;
 	int rc;
 
-	/* Fixup ctf field string in case it using reserved ctf keywords */
-	rc = ctf_fixup_keyword(tp->ctf_field);
-	if (rc)
-		return rc;
-
 	rc = metadata_printf(&str,
 		"event {\n"
 		"    id = %d;\n"
@@ -491,3 +372,43 @@ rte_trace_metadata_dump(FILE *f)
 	rc = fprintf(f, "%s", ctf_meta);
 	return rc < 0 ? rc : 0;
 }
+
+char *trace_metadata_fixup_field(const char *field)
+{
+	static const char * const ctf_reserved_words[] = {
+		"align",
+		"event",
+	};
+	unsigned int i;
+	char *out;
+	char *p;
+
+	/* reserved keywords */
+	for (i = 0; i < RTE_DIM(ctf_reserved_words); i++) {
+		if (strcmp(field, ctf_reserved_words[i]) != 0)
+			continue;
+		if (asprintf(&out, "_%s", ctf_reserved_words[i]) == -1)
+			out = NULL;
+		return out;
+	}
+
+	/* nothing to replace, return early */
+	if (strstr(field, ".") == NULL && strstr(field, "->") == NULL)
+		return NULL;
+
+	out = strdup(field);
+	if (out == NULL)
+		return NULL;
+	p = out;
+	while ((p = strstr(p, ".")) != NULL) {
+		p[0] = '_';
+		p++;
+	}
+	p = out;
+	while ((p = strstr(p, "->")) != NULL) {
+		p[0] = '_';
+		p++;
+		memmove(p, p + 1, strlen(p));
+	}
+	return out;
+}
diff --git a/lib/librte_eal/common/eal_trace.h b/lib/librte_eal/common/eal_trace.h
index 438c2b73f6..8a3f6c5359 100644
--- a/lib/librte_eal/common/eal_trace.h
+++ b/lib/librte_eal/common/eal_trace.h
@@ -104,6 +104,7 @@ bool trace_has_duplicate_entry(void);
 void trace_uuid_generate(void);
 int trace_metadata_create(void);
 void trace_metadata_destroy(void);
+char *trace_metadata_fixup_field(const char *field);
 int trace_mkdir(void);
 int trace_epoch_time_save(void);
 void trace_mem_free(void);
-- 
2.23.0

[dpdk-dev] [PATCH 2/3] trace: remove size limit on CTF event description

[David Marchand]

Rework registration so that it uses dynamic allocations and has no size
limit.

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace.c     | 39 +++++++++-----------
 lib/librte_eal/common/eal_common_trace_ctf.c |  3 +-
 lib/librte_eal/common/eal_trace.h            |  3 +-
 3 files changed, 20 insertions(+), 25 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index 80b458edb6..bc031ca719 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -17,8 +17,7 @@
 
 RTE_DEFINE_PER_LCORE(volatile int, trace_point_sz);
 RTE_DEFINE_PER_LCORE(void *, trace_mem);
-static RTE_DEFINE_PER_LCORE(char, ctf_field[TRACE_CTF_FIELD_SIZE]);
-static RTE_DEFINE_PER_LCORE(int, ctf_count);
+static RTE_DEFINE_PER_LCORE(char *, ctf_field);
 
 static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
 static struct trace trace = { .args = STAILQ_HEAD_INITIALIZER(trace.args), };
@@ -429,32 +428,33 @@ trace_mem_free(void)
 void
 __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 {
-	char *field = RTE_PER_LCORE(ctf_field);
-	int count = RTE_PER_LCORE(ctf_count);
-	size_t size;
+	char *field;
 	char *fixup;
 	int rc;
 
-	size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
-	RTE_PER_LCORE(trace_point_sz) += sz;
 	fixup = trace_metadata_fixup_field(in);
 	if (fixup != NULL)
 		in = fixup;
-	rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
+	rc = asprintf(&field, "%s%s %s;",
+		RTE_PER_LCORE(ctf_field) != NULL ?
+			RTE_PER_LCORE(ctf_field) : "",
+		datatype, in);
+	free(RTE_PER_LCORE(ctf_field));
 	free(fixup);
-	if (rc <= 0 || (size_t)rc >= size) {
+	if (rc == -1) {
 		RTE_PER_LCORE(trace_point_sz) = 0;
-		trace_crit("CTF field is too long");
+		RTE_PER_LCORE(ctf_field) = NULL;
+		trace_crit("could not allocate CTF field");
 		return;
 	}
-	RTE_PER_LCORE(ctf_count) += rc;
+	RTE_PER_LCORE(trace_point_sz) += sz;
+	RTE_PER_LCORE(ctf_field) = field;
 }
 
 int
 __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 		void (*register_fn)(void))
 {
-	char *field = RTE_PER_LCORE(ctf_field);
 	struct trace_point *tp;
 	uint16_t sz;
 
@@ -467,7 +467,6 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 
 	/* Check the size of the trace point object */
 	RTE_PER_LCORE(trace_point_sz) = 0;
-	RTE_PER_LCORE(ctf_count) = 0;
 	register_fn();
 	if (RTE_PER_LCORE(trace_point_sz) == 0) {
 		trace_err("missing rte_trace_emit_header() in register fn");
@@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 		goto free;
 	}
 
-	/* Copy the field data for future use */
-	if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
-		trace_err("CTF field size is too long");
-		rte_errno = E2BIG;
-		goto free;
-	}
-
-	/* Clear field memory for the next event */
-	memset(field, 0, TRACE_CTF_FIELD_SIZE);
+	/* Copy the accumulated fields description and clear it for the next
+	 * trace point.
+	 */
+	tp->ctf_field = RTE_PER_LCORE(ctf_field);
+	RTE_PER_LCORE(ctf_field) = NULL;
 
 	/* Form the trace handle */
 	*handle = sz;
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index bc86432902..884dd0fa4b 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -233,7 +233,8 @@ meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 		"    fields := struct {\n"
 		"        %s\n"
 		"    };\n"
-		"};\n\n", trace_id_get(tp->handle), tp->name, tp->ctf_field);
+		"};\n\n", trace_id_get(tp->handle), tp->name,
+		tp->ctf_field != NULL ? tp->ctf_field : "");
 	return meta_copy(meta, offset, str, rc);
 }
 
diff --git a/lib/librte_eal/common/eal_trace.h b/lib/librte_eal/common/eal_trace.h
index 8a3f6c5359..06751eb23a 100644
--- a/lib/librte_eal/common/eal_trace.h
+++ b/lib/librte_eal/common/eal_trace.h
@@ -24,7 +24,6 @@
 
 #define TRACE_PREFIX_LEN 12
 #define TRACE_DIR_STR_LEN (sizeof("YYYY-mm-dd-AM-HH-MM-SS") + TRACE_PREFIX_LEN)
-#define TRACE_CTF_FIELD_SIZE 448
 #define TRACE_POINT_NAME_SIZE 64
 #define TRACE_CTF_MAGIC 0xC1FC1FC1
 #define TRACE_MAX_ARGS	32
@@ -33,7 +32,7 @@ struct trace_point {
 	STAILQ_ENTRY(trace_point) next;
 	rte_trace_point_t *handle;
 	char name[TRACE_POINT_NAME_SIZE];
-	char ctf_field[TRACE_CTF_FIELD_SIZE];
+	char *ctf_field;
 };
 
 enum trace_area_e {
-- 
2.23.0

Re: [dpdk-dev] [PATCH 2/3] trace: remove size limit on CTF event description

[Jerin Jacob]

On Fri, Oct 23, 2020 at 1:32 PM David Marchand
<david.marchand@redhat.com> wrote:
>
> Rework registration so that it uses dynamic allocations and has no size
> limit.
>
> Signed-off-by: David Marchand <david.marchand@redhat.com>


Reviewed-by: Jerin Jacob <jerinj@marvell.com>



> ---
>  lib/librte_eal/common/eal_common_trace.c     | 39 +++++++++-----------
>  lib/librte_eal/common/eal_common_trace_ctf.c |  3 +-
>  lib/librte_eal/common/eal_trace.h            |  3 +-
>  3 files changed, 20 insertions(+), 25 deletions(-)
>
> diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
> index 80b458edb6..bc031ca719 100644
> --- a/lib/librte_eal/common/eal_common_trace.c
> +++ b/lib/librte_eal/common/eal_common_trace.c
> @@ -17,8 +17,7 @@
>
>  RTE_DEFINE_PER_LCORE(volatile int, trace_point_sz);
>  RTE_DEFINE_PER_LCORE(void *, trace_mem);
> -static RTE_DEFINE_PER_LCORE(char, ctf_field[TRACE_CTF_FIELD_SIZE]);
> -static RTE_DEFINE_PER_LCORE(int, ctf_count);
> +static RTE_DEFINE_PER_LCORE(char *, ctf_field);
>
>  static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
>  static struct trace trace = { .args = STAILQ_HEAD_INITIALIZER(trace.args), };
> @@ -429,32 +428,33 @@ trace_mem_free(void)
>  void
>  __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
>  {
> -       char *field = RTE_PER_LCORE(ctf_field);
> -       int count = RTE_PER_LCORE(ctf_count);
> -       size_t size;
> +       char *field;
>         char *fixup;
>         int rc;
>
> -       size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
> -       RTE_PER_LCORE(trace_point_sz) += sz;
>         fixup = trace_metadata_fixup_field(in);
>         if (fixup != NULL)
>                 in = fixup;
> -       rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
> +       rc = asprintf(&field, "%s%s %s;",
> +               RTE_PER_LCORE(ctf_field) != NULL ?
> +                       RTE_PER_LCORE(ctf_field) : "",
> +               datatype, in);
> +       free(RTE_PER_LCORE(ctf_field));
>         free(fixup);
> -       if (rc <= 0 || (size_t)rc >= size) {
> +       if (rc == -1) {
>                 RTE_PER_LCORE(trace_point_sz) = 0;
> -               trace_crit("CTF field is too long");
> +               RTE_PER_LCORE(ctf_field) = NULL;
> +               trace_crit("could not allocate CTF field");
>                 return;
>         }
> -       RTE_PER_LCORE(ctf_count) += rc;
> +       RTE_PER_LCORE(trace_point_sz) += sz;
> +       RTE_PER_LCORE(ctf_field) = field;
>  }
>
>  int
>  __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
>                 void (*register_fn)(void))
>  {
> -       char *field = RTE_PER_LCORE(ctf_field);
>         struct trace_point *tp;
>         uint16_t sz;
>
> @@ -467,7 +467,6 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
>
>         /* Check the size of the trace point object */
>         RTE_PER_LCORE(trace_point_sz) = 0;
> -       RTE_PER_LCORE(ctf_count) = 0;
>         register_fn();
>         if (RTE_PER_LCORE(trace_point_sz) == 0) {
>                 trace_err("missing rte_trace_emit_header() in register fn");
> @@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
>                 goto free;
>         }
>
> -       /* Copy the field data for future use */
> -       if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
> -               trace_err("CTF field size is too long");
> -               rte_errno = E2BIG;
> -               goto free;
> -       }
> -
> -       /* Clear field memory for the next event */
> -       memset(field, 0, TRACE_CTF_FIELD_SIZE);
> +       /* Copy the accumulated fields description and clear it for the next
> +        * trace point.
> +        */
> +       tp->ctf_field = RTE_PER_LCORE(ctf_field);
> +       RTE_PER_LCORE(ctf_field) = NULL;
>
>         /* Form the trace handle */
>         *handle = sz;
> diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
> index bc86432902..884dd0fa4b 100644
> --- a/lib/librte_eal/common/eal_common_trace_ctf.c
> +++ b/lib/librte_eal/common/eal_common_trace_ctf.c
> @@ -233,7 +233,8 @@ meta_event_emit(char **meta, int *offset, struct trace_point *tp)
>                 "    fields := struct {\n"
>                 "        %s\n"
>                 "    };\n"
> -               "};\n\n", trace_id_get(tp->handle), tp->name, tp->ctf_field);
> +               "};\n\n", trace_id_get(tp->handle), tp->name,
> +               tp->ctf_field != NULL ? tp->ctf_field : "");
>         return meta_copy(meta, offset, str, rc);
>  }
>
> diff --git a/lib/librte_eal/common/eal_trace.h b/lib/librte_eal/common/eal_trace.h
> index 8a3f6c5359..06751eb23a 100644
> --- a/lib/librte_eal/common/eal_trace.h
> +++ b/lib/librte_eal/common/eal_trace.h
> @@ -24,7 +24,6 @@
>
>  #define TRACE_PREFIX_LEN 12
>  #define TRACE_DIR_STR_LEN (sizeof("YYYY-mm-dd-AM-HH-MM-SS") + TRACE_PREFIX_LEN)
> -#define TRACE_CTF_FIELD_SIZE 448
>  #define TRACE_POINT_NAME_SIZE 64
>  #define TRACE_CTF_MAGIC 0xC1FC1FC1
>  #define TRACE_MAX_ARGS 32
> @@ -33,7 +32,7 @@ struct trace_point {
>         STAILQ_ENTRY(trace_point) next;
>         rte_trace_point_t *handle;
>         char name[TRACE_POINT_NAME_SIZE];
> -       char ctf_field[TRACE_CTF_FIELD_SIZE];
> +       char *ctf_field;
>  };
>
>  enum trace_area_e {
> --
> 2.23.0
>

[dpdk-dev] [PATCH 3/3] trace: make CTF metadata prettier

[David Marchand]

This is simply a cosmetic change.

Before:
event {
    id = 17;
    name = "lib.eal.alarm.set";
    fields := struct {
        uint64_t us;uintptr_t cb_fn;uintptr_t cb_arg;int32_t rc;
    };
};

After:
event {
    id = 17;
    name = "lib.eal.alarm.set";
    fields := struct {
        uint64_t us;
        uintptr_t cb_fn;
        uintptr_t cb_arg;
        int32_t rc;
    };
};

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace.c     | 2 +-
 lib/librte_eal/common/eal_common_trace_ctf.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index bc031ca719..24e27387b1 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -435,7 +435,7 @@ __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 	fixup = trace_metadata_fixup_field(in);
 	if (fixup != NULL)
 		in = fixup;
-	rc = asprintf(&field, "%s%s %s;",
+	rc = asprintf(&field, "%s        %s %s;\n",
 		RTE_PER_LCORE(ctf_field) != NULL ?
 			RTE_PER_LCORE(ctf_field) : "",
 		datatype, in);
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index 884dd0fa4b..e66a6c8c87 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -231,7 +231,7 @@ meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 		"    id = %d;\n"
 		"    name = \"%s\";\n"
 		"    fields := struct {\n"
-		"        %s\n"
+		"%s"
 		"    };\n"
 		"};\n\n", trace_id_get(tp->handle), tp->name,
 		tp->ctf_field != NULL ? tp->ctf_field : "");
-- 
2.23.0

Re: [dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[David Marchand]

On Fri, Oct 23, 2020 at 10:01 AM David Marchand
<david.marchand@redhat.com> wrote:
>
> Following recent increase of an internal array that was limiting CTF event
> descriptions, I had a second look at the code.
> All of this is slow path, so I see no reason in keeping this limitation
> and we can go with dynamic allocations.
>
> While at it, I tweaked the metadata file output.
>
> I consider this -rc2 material.

Comments?
Thanks.

-- 
David Marchand

Re: [dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[Jerin Jacob]

On Wed, Oct 28, 2020 at 1:13 AM David Marchand
<david.marchand@redhat.com> wrote:
>
> On Fri, Oct 23, 2020 at 10:01 AM David Marchand
> <david.marchand@redhat.com> wrote:
> >
> > Following recent increase of an internal array that was limiting CTF event
> > descriptions, I had a second look at the code.
> > All of this is slow path, so I see no reason in keeping this limitation
> > and we can go with dynamic allocations.
> >
> > While at it, I tweaked the metadata file output.
> >
> > I consider this -rc2 material.
>
> Comments?
> Thanks.

The Generated metadata has issues. Please check

Reproducer:

echo "trace_autotest" |  ./build/app/test/dpdk-test  -c 0x3 --trace=.*
--no-huge --trace=.*


[main][dpdk.org] $ babeltrace
/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37/
[error] at line 1303: invalid character '0x11'
[error] at line 1303: token "": syntax error, unexpected ERROR
[error] Error creating AST
[warning] Unable to open trace metadata for path
"/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37".
[warning] [Context] Cannot open_trace of format ctf at path
/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37.
[warning] [Context] cannot open trace
"/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37" from
/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37/ for reading.
[error] Cannot open any trace for reading.
[error] opening trace
"/home/jerin/dpdk-traces/rte-2020-10-28-PM-02-02-37/" for reading.
[error] none of the specified trace paths could be opened.



>
> --
> David Marchand
>

Re: [dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[David Marchand]

On Wed, Oct 28, 2020 at 9:53 AM Jerin Jacob <jerinjacobk@gmail.com> wrote:
>
> On Wed, Oct 28, 2020 at 1:13 AM David Marchand
> <david.marchand@redhat.com> wrote:
> >
> > On Fri, Oct 23, 2020 at 10:01 AM David Marchand
> > <david.marchand@redhat.com> wrote:
> > >
> > > Following recent increase of an internal array that was limiting CTF event
> > > descriptions, I had a second look at the code.
> > > All of this is slow path, so I see no reason in keeping this limitation
> > > and we can go with dynamic allocations.
> > >
> > > While at it, I tweaked the metadata file output.
> > >
> > > I consider this -rc2 material.
> >
> > Comments?
> > Thanks.
>
> The Generated metadata has issues. Please check
>
> Reproducer:
>
> echo "trace_autotest" |  ./build/app/test/dpdk-test  -c 0x3 --trace=.*
> --no-huge --trace=.*

Err, indeed, thanks for catching.
I did some diff on metadata files, but did not notice this trailing character.

This is an issue with the metadata string manipulations, that appears
with the last patch...
I ended up rewriting most of _ctf.c (removing intermediate buffers
allocations) and it works but I'll see if I can pinpoint the issue.


-- 
David Marchand

Re: [dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[David Marchand]

On Wed, Oct 28, 2020 at 2:09 PM David Marchand
<david.marchand@redhat.com> wrote:
> > echo "trace_autotest" |  ./build/app/test/dpdk-test  -c 0x3 --trace=.*
> > --no-huge --trace=.*
>
> Err, indeed, thanks for catching.
> I did some diff on metadata files, but did not notice this trailing character.
>
> This is an issue with the metadata string manipulations, that appears
> with the last patch...
> I ended up rewriting most of _ctf.c (removing intermediate buffers
> allocations) and it works but I'll see if I can pinpoint the issue.

The problem is in the current HEAD, but it is revealed by my series,
maybe because the dynamicity around allocations changed.
I see no check on the length of trace->ctf_meta when writing to the
metadata file.
Did I miss something?


int
rte_trace_metadata_dump(FILE *f)
{
...
        rc = fprintf(f, "%s", ctf_meta);
...
}


Breakpoint 1, trace_mkdir () at
../lib/librte_eal/common/eal_common_trace_utils.c:317
317    {
(gdb) p strlen(trace_obj_get()->ctf_meta)
$2 = 21865
(gdb) p trace_obj_get()->ctf_meta[21865]
$3 = 0 '\000'
(gdb) set trace_obj_get()->ctf_meta[21865] = 'A'
...

$ babeltrace $(ls -1rtd $HOME/dpdk-traces/* |tail -1)
[error] at line 1008: token "A": syntax error, unexpected IDENTIFIER
[error] Error creating AST
...


This fixes it:
@@ -37,11 +37,12 @@ meta_copy(char **meta, int *offset, char *str, int rc)
        if (rc < 0)
                return rc;

-       ptr = realloc(ptr, count + rc);
+       ptr = realloc(ptr, count + rc + 1);
        if (ptr == NULL)
                goto free_str;

        memcpy(RTE_PTR_ADD(ptr, count), str, rc);
+       ptr[count + rc] = '\0';
        count += rc;
        free(str);


-- 
David Marchand

Re: [dpdk-dev] [PATCH 0/3] Rework CTF event description storage

[David Marchand]

On Wed, Oct 28, 2020 at 4:17 PM David Marchand
<david.marchand@redhat.com> wrote:
> This fixes it:
> @@ -37,11 +37,12 @@ meta_copy(char **meta, int *offset, char *str, int rc)
>         if (rc < 0)
>                 return rc;
>
> -       ptr = realloc(ptr, count + rc);
> +       ptr = realloc(ptr, count + rc + 1);
>         if (ptr == NULL)
>                 goto free_str;
>
>         memcpy(RTE_PTR_ADD(ptr, count), str, rc);
> +       ptr[count + rc] = '\0';
>         count += rc;
>         free(str);
>

The other alternative is to prefer libc string formatting functions
rather than plain memory alloc + copy + manual null termination:
https://github.com/david-marchand/dpdk/commit/traces


-- 
David Marchand

[dpdk-dev] [PATCH v2 0/4] Rework CTF event description storage

[David Marchand]

Following recent increase of an internal array that was limiting CTF event
descriptions, I had a second look at the code.
All of this is slow path, so I see no reason in keeping this limitation
and we can go with dynamic allocations.

-- 
David Marchand

Changelog since v1:
- fix metadata dump,

David Marchand (4):
  trace: fixup CTF event description at registration
  trace: remove size limit on CTF event description
  trace: fix metadata dump
  trace: make CTF metadata prettier

 lib/librte_eal/common/eal_common_trace.c     |  44 ++---
 lib/librte_eal/common/eal_common_trace_ctf.c | 167 +++++--------------
 lib/librte_eal/common/eal_trace.h            |   4 +-
 3 files changed, 69 insertions(+), 146 deletions(-)

-- 
2.23.0

[dpdk-dev] [PATCH v2 1/4] trace: fixup CTF event description at registration

[David Marchand]

CTF event description is currently built by appending all fields in a
single string at trace point registration.
When dumping the metadata, this string is split again and inspected to
fixup reserved keywords and special tokens like "." or "->".

Move this fixup per field at trace point registration time so that there
is no need for inspecting / string parsing when dumping metadata.
Use dynamic allocations to remove an artificial size limit on the CTF
event description manipulations.

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace.c     |   5 +
 lib/librte_eal/common/eal_common_trace_ctf.c | 159 +++++--------------
 lib/librte_eal/common/eal_trace.h            |   1 +
 3 files changed, 46 insertions(+), 119 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index b6da5537fe..80b458edb6 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -432,11 +432,16 @@ __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 	char *field = RTE_PER_LCORE(ctf_field);
 	int count = RTE_PER_LCORE(ctf_count);
 	size_t size;
+	char *fixup;
 	int rc;
 
 	size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
 	RTE_PER_LCORE(trace_point_sz) += sz;
+	fixup = trace_metadata_fixup_field(in);
+	if (fixup != NULL)
+		in = fixup;
 	rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
+	free(fixup);
 	if (rc <= 0 || (size_t)rc >= size) {
 		RTE_PER_LCORE(trace_point_sz) = 0;
 		trace_crit("CTF field is too long");
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index 9dc91df0fb..174cdac1b0 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -220,131 +220,12 @@ meta_stream_emit(char **meta, int *offset)
 	return meta_copy(meta, offset, str, rc);
 }
 
-static void
-string_fixed_replace(char *input, const char *search, const char *replace)
-{
-	char *found;
-	size_t len;
-
-	found = strstr(input, search);
-	if (found == NULL)
-		return;
-
-	if (strlen(found) != strlen(search))
-		return;
-
-	len = strlen(replace);
-	memcpy(found, replace, len);
-	found[len] = '\0';
-}
-
-static void
-ctf_fixup_align(char *str)
-{
-	string_fixed_replace(str, "align", "_align");
-}
-
-static void
-ctf_fixup_arrow_deref(char *str)
-{
-	const char *replace = "_";
-	const char *search = "->";
-	char *found;
-	size_t len;
-
-	found = strstr(str, search);
-	if (found == NULL)
-		return;
-
-	do {
-		memcpy(found, replace, strlen(replace));
-		len = strlen(found + 2);
-		memcpy(found + 1, found + 2, len);
-		found[len + 1] = '\0';
-		found = strstr(str, search);
-	} while (found != NULL);
-}
-
-static void
-ctf_fixup_dot_deref(char *str)
-{
-	const char *replace = "_";
-	const char *search = ".";
-	char *found;
-	size_t len;
-
-	found = strstr(str, search);
-	if (found == NULL)
-		return;
-
-	len = strlen(replace);
-	do {
-		memcpy(found, replace, len);
-		found = strstr(str, search);
-	} while (found != NULL);
-}
-
-static void
-ctf_fixup_event(char *str)
-{
-	string_fixed_replace(str, "event", "_event");
-}
-
-static int
-ctf_fixup_keyword(char *str)
-{
-	char dup_str[TRACE_CTF_FIELD_SIZE];
-	char input[TRACE_CTF_FIELD_SIZE];
-	const char *delim = ";";
-	char *from;
-	int len;
-
-	if (str == NULL)
-		return 0;
-
-	len = strlen(str);
-	if (len >= TRACE_CTF_FIELD_SIZE) {
-		trace_err("ctf_field reached its maximum limit");
-		return -EMSGSIZE;
-	}
-
-	/* Create duplicate string */
-	strcpy(dup_str, str);
-
-	len = 0;
-	from = strtok(dup_str, delim);
-	while (from != NULL) {
-		strcpy(input, from);
-		ctf_fixup_align(input);
-		ctf_fixup_dot_deref(input);
-		ctf_fixup_arrow_deref(input);
-		ctf_fixup_event(input);
-
-		strcpy(&input[strlen(input)], delim);
-		if ((len + strlen(input)) >= TRACE_CTF_FIELD_SIZE) {
-			trace_err("ctf_field reached its maximum limit");
-			return -EMSGSIZE;
-		}
-
-		strcpy(str + len, input);
-		len += strlen(input);
-		from = strtok(NULL, delim);
-	}
-
-	return 0;
-}
-
 static int
 meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 {
 	char *str = NULL;
 	int rc;
 
-	/* Fixup ctf field string in case it using reserved ctf keywords */
-	rc = ctf_fixup_keyword(tp->ctf_field);
-	if (rc)
-		return rc;
-
 	rc = metadata_printf(&str,
 		"event {\n"
 		"    id = %d;\n"
@@ -491,3 +372,43 @@ rte_trace_metadata_dump(FILE *f)
 	rc = fprintf(f, "%s", ctf_meta);
 	return rc < 0 ? rc : 0;
 }
+
+char *trace_metadata_fixup_field(const char *field)
+{
+	const char *ctf_reserved_words[] = {
+		"align",
+		"event",
+	};
+	unsigned int i;
+	char *out;
+	char *p;
+
+	/* reserved keywords */
+	for (i = 0; i < RTE_DIM(ctf_reserved_words); i++) {
+		if (strcmp(field, ctf_reserved_words[i]) != 0)
+			continue;
+		if (asprintf(&out, "_%s", ctf_reserved_words[i]) == -1)
+			out = NULL;
+		return out;
+	}
+
+	/* nothing to replace, return early */
+	if (strstr(field, ".") == NULL && strstr(field, "->") == NULL)
+		return NULL;
+
+	out = strdup(field);
+	if (out == NULL)
+		return NULL;
+	p = out;
+	while ((p = strstr(p, ".")) != NULL) {
+		p[0] = '_';
+		p++;
+	}
+	p = out;
+	while ((p = strstr(p, "->")) != NULL) {
+		p[0] = '_';
+		p++;
+		memmove(p, p + 1, strlen(p));
+	}
+	return out;
+}
diff --git a/lib/librte_eal/common/eal_trace.h b/lib/librte_eal/common/eal_trace.h
index 438c2b73f6..8a3f6c5359 100644
--- a/lib/librte_eal/common/eal_trace.h
+++ b/lib/librte_eal/common/eal_trace.h
@@ -104,6 +104,7 @@ bool trace_has_duplicate_entry(void);
 void trace_uuid_generate(void);
 int trace_metadata_create(void);
 void trace_metadata_destroy(void);
+char *trace_metadata_fixup_field(const char *field);
 int trace_mkdir(void);
 int trace_epoch_time_save(void);
 void trace_mem_free(void);
-- 
2.23.0

Re: [dpdk-dev] [EXT] [PATCH v2 1/4] trace: fixup CTF event description at registration

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 2:33 AM
>To: dev@dpdk.org
>Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Sunil Kumar Kori
><skori@marvell.com>
>Subject: [EXT] [PATCH v2 1/4] trace: fixup CTF event description at registration
>
>External Email
>
>----------------------------------------------------------------------
>CTF event description is currently built by appending all fields in a single string
>at trace point registration.
>When dumping the metadata, this string is split again and inspected to fixup
>reserved keywords and special tokens like "." or "->".
>
>Move this fixup per field at trace point registration time so that there is no
>need for inspecting / string parsing when dumping metadata.
>Use dynamic allocations to remove an artificial size limit on the CTF event
>description manipulations.
>
>Signed-off-by: David Marchand <david.marchand@redhat.com>

Acked-by: Sunil Kumar Kori <skori@mavell.com>

[snipped]

>--
>2.23.0

[dpdk-dev] [PATCH v2 2/4] trace: remove size limit on CTF event description

[David Marchand]

Rework registration so that it uses dynamic allocations and has no size
limit.

Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Jerin Jacob <jerinj@marvell.com>
---
 lib/librte_eal/common/eal_common_trace.c     | 39 +++++++++-----------
 lib/librte_eal/common/eal_common_trace_ctf.c |  3 +-
 lib/librte_eal/common/eal_trace.h            |  3 +-
 3 files changed, 20 insertions(+), 25 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index 80b458edb6..bc031ca719 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -17,8 +17,7 @@
 
 RTE_DEFINE_PER_LCORE(volatile int, trace_point_sz);
 RTE_DEFINE_PER_LCORE(void *, trace_mem);
-static RTE_DEFINE_PER_LCORE(char, ctf_field[TRACE_CTF_FIELD_SIZE]);
-static RTE_DEFINE_PER_LCORE(int, ctf_count);
+static RTE_DEFINE_PER_LCORE(char *, ctf_field);
 
 static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
 static struct trace trace = { .args = STAILQ_HEAD_INITIALIZER(trace.args), };
@@ -429,32 +428,33 @@ trace_mem_free(void)
 void
 __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 {
-	char *field = RTE_PER_LCORE(ctf_field);
-	int count = RTE_PER_LCORE(ctf_count);
-	size_t size;
+	char *field;
 	char *fixup;
 	int rc;
 
-	size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
-	RTE_PER_LCORE(trace_point_sz) += sz;
 	fixup = trace_metadata_fixup_field(in);
 	if (fixup != NULL)
 		in = fixup;
-	rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
+	rc = asprintf(&field, "%s%s %s;",
+		RTE_PER_LCORE(ctf_field) != NULL ?
+			RTE_PER_LCORE(ctf_field) : "",
+		datatype, in);
+	free(RTE_PER_LCORE(ctf_field));
 	free(fixup);
-	if (rc <= 0 || (size_t)rc >= size) {
+	if (rc == -1) {
 		RTE_PER_LCORE(trace_point_sz) = 0;
-		trace_crit("CTF field is too long");
+		RTE_PER_LCORE(ctf_field) = NULL;
+		trace_crit("could not allocate CTF field");
 		return;
 	}
-	RTE_PER_LCORE(ctf_count) += rc;
+	RTE_PER_LCORE(trace_point_sz) += sz;
+	RTE_PER_LCORE(ctf_field) = field;
 }
 
 int
 __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 		void (*register_fn)(void))
 {
-	char *field = RTE_PER_LCORE(ctf_field);
 	struct trace_point *tp;
 	uint16_t sz;
 
@@ -467,7 +467,6 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 
 	/* Check the size of the trace point object */
 	RTE_PER_LCORE(trace_point_sz) = 0;
-	RTE_PER_LCORE(ctf_count) = 0;
 	register_fn();
 	if (RTE_PER_LCORE(trace_point_sz) == 0) {
 		trace_err("missing rte_trace_emit_header() in register fn");
@@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
 		goto free;
 	}
 
-	/* Copy the field data for future use */
-	if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
-		trace_err("CTF field size is too long");
-		rte_errno = E2BIG;
-		goto free;
-	}
-
-	/* Clear field memory for the next event */
-	memset(field, 0, TRACE_CTF_FIELD_SIZE);
+	/* Copy the accumulated fields description and clear it for the next
+	 * trace point.
+	 */
+	tp->ctf_field = RTE_PER_LCORE(ctf_field);
+	RTE_PER_LCORE(ctf_field) = NULL;
 
 	/* Form the trace handle */
 	*handle = sz;
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index 174cdac1b0..ac1f64d04b 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -233,7 +233,8 @@ meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 		"    fields := struct {\n"
 		"        %s\n"
 		"    };\n"
-		"};\n\n", trace_id_get(tp->handle), tp->name, tp->ctf_field);
+		"};\n\n", trace_id_get(tp->handle), tp->name,
+		tp->ctf_field != NULL ? tp->ctf_field : "");
 	return meta_copy(meta, offset, str, rc);
 }
 
diff --git a/lib/librte_eal/common/eal_trace.h b/lib/librte_eal/common/eal_trace.h
index 8a3f6c5359..06751eb23a 100644
--- a/lib/librte_eal/common/eal_trace.h
+++ b/lib/librte_eal/common/eal_trace.h
@@ -24,7 +24,6 @@
 
 #define TRACE_PREFIX_LEN 12
 #define TRACE_DIR_STR_LEN (sizeof("YYYY-mm-dd-AM-HH-MM-SS") + TRACE_PREFIX_LEN)
-#define TRACE_CTF_FIELD_SIZE 448
 #define TRACE_POINT_NAME_SIZE 64
 #define TRACE_CTF_MAGIC 0xC1FC1FC1
 #define TRACE_MAX_ARGS	32
@@ -33,7 +32,7 @@ struct trace_point {
 	STAILQ_ENTRY(trace_point) next;
 	rte_trace_point_t *handle;
 	char name[TRACE_POINT_NAME_SIZE];
-	char ctf_field[TRACE_CTF_FIELD_SIZE];
+	char *ctf_field;
 };
 
 enum trace_area_e {
-- 
2.23.0

Re: [dpdk-dev] [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 2:33 AM
>To: dev@dpdk.org
>Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Sunil Kumar Kori
><skori@marvell.com>
>Subject: [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description
>
>External Email
>
>----------------------------------------------------------------------
>Rework registration so that it uses dynamic allocations and has no size limit.
>
>Signed-off-by: David Marchand <david.marchand@redhat.com>
>Reviewed-by: Jerin Jacob <jerinj@marvell.com>
>---
> lib/librte_eal/common/eal_common_trace.c     | 39 +++++++++-----------
> lib/librte_eal/common/eal_common_trace_ctf.c |  3 +-
> lib/librte_eal/common/eal_trace.h            |  3 +-
> 3 files changed, 20 insertions(+), 25 deletions(-)
>
>diff --git a/lib/librte_eal/common/eal_common_trace.c
>b/lib/librte_eal/common/eal_common_trace.c
>index 80b458edb6..bc031ca719 100644
>--- a/lib/librte_eal/common/eal_common_trace.c
>+++ b/lib/librte_eal/common/eal_common_trace.c
>@@ -17,8 +17,7 @@
>
> RTE_DEFINE_PER_LCORE(volatile int, trace_point_sz);
>RTE_DEFINE_PER_LCORE(void *, trace_mem); -static
>RTE_DEFINE_PER_LCORE(char, ctf_field[TRACE_CTF_FIELD_SIZE]); -static
>RTE_DEFINE_PER_LCORE(int, ctf_count);
>+static RTE_DEFINE_PER_LCORE(char *, ctf_field);
>
> static struct trace_point_head tp_list = STAILQ_HEAD_INITIALIZER(tp_list);
>static struct trace trace = { .args = STAILQ_HEAD_INITIALIZER(trace.args), };
>@@ -429,32 +428,33 @@ trace_mem_free(void)  void
>__rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)  {
>-	char *field = RTE_PER_LCORE(ctf_field);
>-	int count = RTE_PER_LCORE(ctf_count);
>-	size_t size;
>+	char *field;
> 	char *fixup;
> 	int rc;
>
>-	size = RTE_MAX(0, TRACE_CTF_FIELD_SIZE - 1 - count);
>-	RTE_PER_LCORE(trace_point_sz) += sz;
> 	fixup = trace_metadata_fixup_field(in);
> 	if (fixup != NULL)
> 		in = fixup;
>-	rc = snprintf(RTE_PTR_ADD(field, count), size, "%s %s;", datatype, in);
>+	rc = asprintf(&field, "%s%s %s;",
>+		RTE_PER_LCORE(ctf_field) != NULL ?
>+			RTE_PER_LCORE(ctf_field) : "",
>+		datatype, in);
>+	free(RTE_PER_LCORE(ctf_field));
> 	free(fixup);
>-	if (rc <= 0 || (size_t)rc >= size) {
>+	if (rc == -1) {
> 		RTE_PER_LCORE(trace_point_sz) = 0;
>-		trace_crit("CTF field is too long");
>+		RTE_PER_LCORE(ctf_field) = NULL;
>+		trace_crit("could not allocate CTF field");
> 		return;
> 	}
>-	RTE_PER_LCORE(ctf_count) += rc;
>+	RTE_PER_LCORE(trace_point_sz) += sz;
>+	RTE_PER_LCORE(ctf_field) = field;
> }
>
> int
> __rte_trace_point_register(rte_trace_point_t *handle, const char *name,
> 		void (*register_fn)(void))
> {
>-	char *field = RTE_PER_LCORE(ctf_field);
> 	struct trace_point *tp;
> 	uint16_t sz;
>
>@@ -467,7 +467,6 @@ __rte_trace_point_register(rte_trace_point_t *handle,
>const char *name,
>
> 	/* Check the size of the trace point object */
> 	RTE_PER_LCORE(trace_point_sz) = 0;
>-	RTE_PER_LCORE(ctf_count) = 0;
> 	register_fn();
> 	if (RTE_PER_LCORE(trace_point_sz) == 0) {
> 		trace_err("missing rte_trace_emit_header() in register fn");
>@@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t
>*handle, const char *name,
> 		goto free;
> 	}
>
>-	/* Copy the field data for future use */
>-	if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
>-		trace_err("CTF field size is too long");
>-		rte_errno = E2BIG;
>-		goto free;
>-	}
>-
>-	/* Clear field memory for the next event */
>-	memset(field, 0, TRACE_CTF_FIELD_SIZE);
>+	/* Copy the accumulated fields description and clear it for the next
>+	 * trace point.
>+	 */
>+	tp->ctf_field = RTE_PER_LCORE(ctf_field);
>+	RTE_PER_LCORE(ctf_field) = NULL;

Although patch looks okay but I have one that how "tp->ctf_field" is populated because during
registration time RTE_PER_LCORE(ctf_field) will be NULL. So "tp->ctf_field" will always be NULL.
>
> 	/* Form the trace handle */
> 	*handle = sz;
>diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c
>b/lib/librte_eal/common/eal_common_trace_ctf.c
>index 174cdac1b0..ac1f64d04b 100644
>--- a/lib/librte_eal/common/eal_common_trace_ctf.c
>+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
>@@ -233,7 +233,8 @@ meta_event_emit(char **meta, int *offset, struct
>trace_point *tp)
> 		"    fields := struct {\n"
> 		"        %s\n"
> 		"    };\n"
>-		"};\n\n", trace_id_get(tp->handle), tp->name, tp->ctf_field);
>+		"};\n\n", trace_id_get(tp->handle), tp->name,
>+		tp->ctf_field != NULL ? tp->ctf_field : "");
> 	return meta_copy(meta, offset, str, rc);  }
>
>diff --git a/lib/librte_eal/common/eal_trace.h
>b/lib/librte_eal/common/eal_trace.h
>index 8a3f6c5359..06751eb23a 100644
>--- a/lib/librte_eal/common/eal_trace.h
>+++ b/lib/librte_eal/common/eal_trace.h
>@@ -24,7 +24,6 @@
>
> #define TRACE_PREFIX_LEN 12
> #define TRACE_DIR_STR_LEN (sizeof("YYYY-mm-dd-AM-HH-MM-SS") +
>TRACE_PREFIX_LEN) -#define TRACE_CTF_FIELD_SIZE 448  #define
>TRACE_POINT_NAME_SIZE 64  #define TRACE_CTF_MAGIC 0xC1FC1FC1
> #define TRACE_MAX_ARGS	32
>@@ -33,7 +32,7 @@ struct trace_point {
> 	STAILQ_ENTRY(trace_point) next;
> 	rte_trace_point_t *handle;
> 	char name[TRACE_POINT_NAME_SIZE];
>-	char ctf_field[TRACE_CTF_FIELD_SIZE];
>+	char *ctf_field;
> };
>
> enum trace_area_e {
>--
>2.23.0

Re: [dpdk-dev] [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description

[David Marchand]

On Thu, Oct 29, 2020 at 9:41 AM Sunil Kumar Kori <skori@marvell.com> wrote:
> >@@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t
> >*handle, const char *name,
> >               goto free;
> >       }
> >
> >-      /* Copy the field data for future use */
> >-      if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
> >-              trace_err("CTF field size is too long");
> >-              rte_errno = E2BIG;
> >-              goto free;
> >-      }
> >-
> >-      /* Clear field memory for the next event */
> >-      memset(field, 0, TRACE_CTF_FIELD_SIZE);
> >+      /* Copy the accumulated fields description and clear it for the next
> >+       * trace point.
> >+       */
> >+      tp->ctf_field = RTE_PER_LCORE(ctf_field);
> >+      RTE_PER_LCORE(ctf_field) = NULL;
>
> Although patch looks okay but I have one that how "tp->ctf_field" is populated because during
> registration time RTE_PER_LCORE(ctf_field) will be NULL. So "tp->ctf_field" will always be NULL.

Sorry, I don't understand your comment.
RTE_PER_LCORE(ctf_field) is filled at __rte_trace_point_emit_field.


-- 
David Marchand

Re: [dpdk-dev] [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 2:22 PM
>To: Sunil Kumar Kori <skori@marvell.com>
>Cc: dev@dpdk.org; Jerin Jacob Kollanukkaran <jerinj@marvell.com>
>Subject: Re: [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event
>description
>
>On Thu, Oct 29, 2020 at 9:41 AM Sunil Kumar Kori <skori@marvell.com>
>wrote:
>> >@@ -505,15 +504,11 @@ __rte_trace_point_register(rte_trace_point_t
>> >*handle, const char *name,
>> >               goto free;
>> >       }
>> >
>> >-      /* Copy the field data for future use */
>> >-      if (rte_strscpy(tp->ctf_field, field, TRACE_CTF_FIELD_SIZE) < 0) {
>> >-              trace_err("CTF field size is too long");
>> >-              rte_errno = E2BIG;
>> >-              goto free;
>> >-      }
>> >-
>> >-      /* Clear field memory for the next event */
>> >-      memset(field, 0, TRACE_CTF_FIELD_SIZE);
>> >+      /* Copy the accumulated fields description and clear it for the next
>> >+       * trace point.
>> >+       */
>> >+      tp->ctf_field = RTE_PER_LCORE(ctf_field);
>> >+      RTE_PER_LCORE(ctf_field) = NULL;
>>
>> Although patch looks okay but I have one that how "tp->ctf_field" is
>> populated because during registration time RTE_PER_LCORE(ctf_field) will
>be NULL. So "tp->ctf_field" will always be NULL.
>
>Sorry, I don't understand your comment.
>RTE_PER_LCORE(ctf_field) is filled at __rte_trace_point_emit_field.

Yes but I am not able to understand that how tp->ctf_field will be populated with latest memory
because RTE_PER_LCORE(ctf_field) is being free and re-allocated at runtime. 
>
>
>--
>David Marchand

Re: [dpdk-dev] [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description

[David Marchand]

On Thu, Oct 29, 2020 at 10:36 AM Sunil Kumar Kori <skori@marvell.com> wrote:
> Yes but I am not able to understand that how tp->ctf_field will be populated with latest memory
> because RTE_PER_LCORE(ctf_field) is being free and re-allocated at runtime.

Initially, RTE_PER_LCORE(ctf_field) is NULL.

Then registration for a trace point happens:

__rte_trace_point_register() calls register_fn() which for each field
in the trace point calls __rte_trace_point_emit_field().

Each call to __rte_trace_point_emit_field accumulates the previous
ctf_field with the new field.

        rc = asprintf(&field, "%s        %s %s;\n",
                RTE_PER_LCORE(ctf_field) != NULL ?
                        RTE_PER_LCORE(ctf_field) : "",
                datatype, in);
        free(RTE_PER_LCORE(ctf_field));
        RTE_PER_LCORE(ctf_field) = field;

Here, RTE_PER_LCORE(ctf_field) is != NULL.

Back to __rte_trace_point_register:

        /* Copy the accumulated fields description and clear it for the next
         * trace point.
         */
        tp->ctf_field = RTE_PER_LCORE(ctf_field);

Once stored, RTE_PER_LCORE(ctf_field) is cleared again for the next
trace point registration.

        RTE_PER_LCORE(ctf_field) = NULL;



-- 
David Marchand

Re: [dpdk-dev] [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event description

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 3:33 PM
>To: Sunil Kumar Kori <skori@marvell.com>
>Cc: dev@dpdk.org; Jerin Jacob Kollanukkaran <jerinj@marvell.com>
>Subject: Re: [EXT] [PATCH v2 2/4] trace: remove size limit on CTF event
>description
>
>On Thu, Oct 29, 2020 at 10:36 AM Sunil Kumar Kori <skori@marvell.com>
>wrote:
>> Yes but I am not able to understand that how tp->ctf_field will be
>> populated with latest memory because RTE_PER_LCORE(ctf_field) is being
>free and re-allocated at runtime.
>
>Initially, RTE_PER_LCORE(ctf_field) is NULL.
>
>Then registration for a trace point happens:
>
>__rte_trace_point_register() calls register_fn() which for each field in the trace
>point calls __rte_trace_point_emit_field().
>
>Each call to __rte_trace_point_emit_field accumulates the previous ctf_field
>with the new field.
>
>        rc = asprintf(&field, "%s        %s %s;\n",
>                RTE_PER_LCORE(ctf_field) != NULL ?
>                        RTE_PER_LCORE(ctf_field) : "",
>                datatype, in);
>        free(RTE_PER_LCORE(ctf_field));
>        RTE_PER_LCORE(ctf_field) = field;
>
>Here, RTE_PER_LCORE(ctf_field) is != NULL.
>
>Back to __rte_trace_point_register:
>
>        /* Copy the accumulated fields description and clear it for the next
>         * trace point.
>         */
>        tp->ctf_field = RTE_PER_LCORE(ctf_field);
>
>Once stored, RTE_PER_LCORE(ctf_field) is cleared again for the next trace
>point registration.
>
>        RTE_PER_LCORE(ctf_field) = NULL;
>
>
>

Acked-by: Sunil Kumar Kori <skori@mavell.com>
>--
>David Marchand

[dpdk-dev] [PATCH v2 3/4] trace: fix metadata dump

[David Marchand]

The ctf metadata is written to the metadata file without any check for
length, so this string must be null terminated.

Fixes: f1a099f5b1f1 ("trace: create CTF TDSL metadata in memory")

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace_ctf.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index ac1f64d04b..22615c4e73 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -37,11 +37,12 @@ meta_copy(char **meta, int *offset, char *str, int rc)
 	if (rc < 0)
 		return rc;
 
-	ptr = realloc(ptr, count + rc);
+	ptr = realloc(ptr, count + rc + 1);
 	if (ptr == NULL)
 		goto free_str;
 
 	memcpy(RTE_PTR_ADD(ptr, count), str, rc);
+	ptr[count + rc] = '\0';
 	count += rc;
 	free(str);
 
-- 
2.23.0

Re: [dpdk-dev] [EXT] [PATCH v2 3/4] trace: fix metadata dump

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 2:33 AM
>To: dev@dpdk.org
>Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Sunil Kumar Kori
><skori@marvell.com>
>Subject: [EXT] [PATCH v2 3/4] trace: fix metadata dump
>
>External Email
>
>----------------------------------------------------------------------
>The ctf metadata is written to the metadata file without any check for length,
>so this string must be null terminated.
>
>Fixes: f1a099f5b1f1 ("trace: create CTF TDSL metadata in memory")
>
>Signed-off-by: David Marchand <david.marchand@redhat.com>
>---
> lib/librte_eal/common/eal_common_trace_ctf.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
>diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c
>b/lib/librte_eal/common/eal_common_trace_ctf.c
>index ac1f64d04b..22615c4e73 100644
>--- a/lib/librte_eal/common/eal_common_trace_ctf.c
>+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
>@@ -37,11 +37,12 @@ meta_copy(char **meta, int *offset, char *str, int rc)
> 	if (rc < 0)
> 		return rc;
>
>-	ptr = realloc(ptr, count + rc);
>+	ptr = realloc(ptr, count + rc + 1);
> 	if (ptr == NULL)
> 		goto free_str;
>
> 	memcpy(RTE_PTR_ADD(ptr, count), str, rc);
>+	ptr[count + rc] = '\0';
> 	count += rc;
> 	free(str);
>
>--
>2.23.0
Acked-by: Sunil Kumar Kori <skori@mavell.com>

[dpdk-dev] [PATCH v2 4/4] trace: make CTF metadata prettier

[David Marchand]

This is simply a cosmetic change.

Before:
event {
    id = 17;
    name = "lib.eal.alarm.set";
    fields := struct {
        uint64_t us;uintptr_t cb_fn;uintptr_t cb_arg;int32_t rc;
    };
};

After:
event {
    id = 17;
    name = "lib.eal.alarm.set";
    fields := struct {
        uint64_t us;
        uintptr_t cb_fn;
        uintptr_t cb_arg;
        int32_t rc;
    };
};

Signed-off-by: David Marchand <david.marchand@redhat.com>
---
 lib/librte_eal/common/eal_common_trace.c     | 2 +-
 lib/librte_eal/common/eal_common_trace_ctf.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/librte_eal/common/eal_common_trace.c b/lib/librte_eal/common/eal_common_trace.c
index bc031ca719..24e27387b1 100644
--- a/lib/librte_eal/common/eal_common_trace.c
+++ b/lib/librte_eal/common/eal_common_trace.c
@@ -435,7 +435,7 @@ __rte_trace_point_emit_field(size_t sz, const char *in, const char *datatype)
 	fixup = trace_metadata_fixup_field(in);
 	if (fixup != NULL)
 		in = fixup;
-	rc = asprintf(&field, "%s%s %s;",
+	rc = asprintf(&field, "%s        %s %s;\n",
 		RTE_PER_LCORE(ctf_field) != NULL ?
 			RTE_PER_LCORE(ctf_field) : "",
 		datatype, in);
diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c b/lib/librte_eal/common/eal_common_trace_ctf.c
index 22615c4e73..33e419aac7 100644
--- a/lib/librte_eal/common/eal_common_trace_ctf.c
+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
@@ -232,7 +232,7 @@ meta_event_emit(char **meta, int *offset, struct trace_point *tp)
 		"    id = %d;\n"
 		"    name = \"%s\";\n"
 		"    fields := struct {\n"
-		"        %s\n"
+		"%s"
 		"    };\n"
 		"};\n\n", trace_id_get(tp->handle), tp->name,
 		tp->ctf_field != NULL ? tp->ctf_field : "");
-- 
2.23.0

Re: [dpdk-dev] [EXT] [PATCH v2 4/4] trace: make CTF metadata prettier

[Sunil Kumar Kori]

>-----Original Message-----
>From: David Marchand <david.marchand@redhat.com>
>Sent: Thursday, October 29, 2020 2:33 AM
>To: dev@dpdk.org
>Cc: Jerin Jacob Kollanukkaran <jerinj@marvell.com>; Sunil Kumar Kori
><skori@marvell.com>
>Subject: [EXT] [PATCH v2 4/4] trace: make CTF metadata prettier
>
>External Email
>
>----------------------------------------------------------------------
>This is simply a cosmetic change.
>
>Before:
>event {
>    id = 17;
>    name = "lib.eal.alarm.set";
>    fields := struct {
>        uint64_t us;uintptr_t cb_fn;uintptr_t cb_arg;int32_t rc;
>    };
>};
>
>After:
>event {
>    id = 17;
>    name = "lib.eal.alarm.set";
>    fields := struct {
>        uint64_t us;
>        uintptr_t cb_fn;
>        uintptr_t cb_arg;
>        int32_t rc;
>    };
>};
>
>Signed-off-by: David Marchand <david.marchand@redhat.com>
>---
> lib/librte_eal/common/eal_common_trace.c     | 2 +-
> lib/librte_eal/common/eal_common_trace_ctf.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
>diff --git a/lib/librte_eal/common/eal_common_trace.c
>b/lib/librte_eal/common/eal_common_trace.c
>index bc031ca719..24e27387b1 100644
>--- a/lib/librte_eal/common/eal_common_trace.c
>+++ b/lib/librte_eal/common/eal_common_trace.c
>@@ -435,7 +435,7 @@ __rte_trace_point_emit_field(size_t sz, const char *in,
>const char *datatype)
> 	fixup = trace_metadata_fixup_field(in);
> 	if (fixup != NULL)
> 		in = fixup;
>-	rc = asprintf(&field, "%s%s %s;",
>+	rc = asprintf(&field, "%s        %s %s;\n",
> 		RTE_PER_LCORE(ctf_field) != NULL ?
> 			RTE_PER_LCORE(ctf_field) : "",
> 		datatype, in);
>diff --git a/lib/librte_eal/common/eal_common_trace_ctf.c
>b/lib/librte_eal/common/eal_common_trace_ctf.c
>index 22615c4e73..33e419aac7 100644
>--- a/lib/librte_eal/common/eal_common_trace_ctf.c
>+++ b/lib/librte_eal/common/eal_common_trace_ctf.c
>@@ -232,7 +232,7 @@ meta_event_emit(char **meta, int *offset, struct
>trace_point *tp)
> 		"    id = %d;\n"
> 		"    name = \"%s\";\n"
> 		"    fields := struct {\n"
>-		"        %s\n"
>+		"%s"
> 		"    };\n"
> 		"};\n\n", trace_id_get(tp->handle), tp->name,
> 		tp->ctf_field != NULL ? tp->ctf_field : "");
>--
>2.23.0

Acked-by: Sunil Kumar Kori <skori@mavell.com>

Re: [dpdk-dev] [PATCH v2 0/4] Rework CTF event description storage

[David Marchand]

On Wed, Oct 28, 2020 at 10:03 PM David Marchand
<david.marchand@redhat.com> wrote:
>
> Following recent increase of an internal array that was limiting CTF event
> descriptions, I had a second look at the code.
> All of this is slow path, so I see no reason in keeping this limitation
> and we can go with dynamic allocations.
>
> David Marchand (4):
>   trace: fixup CTF event description at registration
>   trace: remove size limit on CTF event description
>   trace: fix metadata dump
>   trace: make CTF metadata prettier
>
>  lib/librte_eal/common/eal_common_trace.c     |  44 ++---
>  lib/librte_eal/common/eal_common_trace_ctf.c | 167 +++++--------------
>  lib/librte_eal/common/eal_trace.h            |   4 +-
>  3 files changed, 69 insertions(+), 146 deletions(-)

Applied.

-- 
David Marchand