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From: "Mattias Rönnblom" <hofors@lysator.liu.se>
To: David Marchand <david.marchand@redhat.com>, dev@dpdk.org
Cc: "Morten Brørup" <mb@smartsharesystems.com>,
	"Bruce Richardson" <bruce.richardson@intel.com>,
	"Ciara Power" <ciara.power@intel.com>
Subject: Re: [PATCH v3 1/4] telemetry: support boolean type
Date: Tue, 25 Oct 2022 11:34:01 +0200	[thread overview]
Message-ID: <6de84928-8f39-7e82-44ec-da40eb992380@lysator.liu.se> (raw)
In-Reply-To: <20221025090052.429232-2-david.marchand@redhat.com>

On 2022-10-25 11:00, David Marchand wrote:
> Add the boolean type RTE_TEL_BOOL_VAL for values in arrays and dicts.
> 
> Signed-off-by: David Marchand <david.marchand@redhat.com>
> Acked-by: Morten Brørup <mb@smartsharesystems.com>
> Acked-by: Bruce Richardson <bruce.richardson@intel.com>
> Acked-by: Ciara Power <ciara.power@intel.com>
> ---
> Changes since v1:
> - fixed doxygen description,
> 
> ---
>   app/test/test_telemetry_data.c | 88 +++++++++++++++++++++++++++++++++-
>   lib/telemetry/rte_telemetry.h  | 36 ++++++++++++++
>   lib/telemetry/telemetry.c      | 24 +++++++++-
>   lib/telemetry/telemetry_data.c | 44 +++++++++++++++--
>   lib/telemetry/telemetry_data.h |  5 ++
>   lib/telemetry/telemetry_json.h | 34 +++++++++++++
>   lib/telemetry/version.map      | 10 ++++
>   7 files changed, 233 insertions(+), 8 deletions(-)
> 
> diff --git a/app/test/test_telemetry_data.c b/app/test/test_telemetry_data.c
> index d92667a527..134e018fde 100644
> --- a/app/test/test_telemetry_data.c
> +++ b/app/test/test_telemetry_data.c
> @@ -353,6 +353,84 @@ test_array_with_array_u64_values(void)
>   	return CHECK_OUTPUT("[[0,1,2,3,4],[0,1,2,3,4]]");
>   }
>   
> +static int
> +test_case_array_bool(void)
> +{
> +	int i;
> +
> +	rte_tel_data_start_array(&response_data, RTE_TEL_BOOL_VAL);
> +	for (i = 0; i < 5; i++)
> +		rte_tel_data_add_array_bool(&response_data, (i % 2) == 0);
> +	return CHECK_OUTPUT("[true,false,true,false,true]");
> +}
> +
> +static int
> +test_case_add_dict_bool(void)
> +{
> +	int i = 0;
> +	char name_of_value[8];
> +
> +	rte_tel_data_start_dict(&response_data);
> +
> +	for (i = 0; i < 5; i++) {
> +		sprintf(name_of_value, "dict_%d", i);
> +		rte_tel_data_add_dict_bool(&response_data, name_of_value,
> +			(i % 2) == 0);
> +	}
> +	return CHECK_OUTPUT("{\"dict_0\":true,\"dict_1\":false,\"dict_2\":true,"
> +		"\"dict_3\":false,\"dict_4\":true}");
> +}
> +
> +static int
> +test_dict_with_array_bool_values(void)
> +{
> +	int i;
> +
> +	struct rte_tel_data *child_data = rte_tel_data_alloc();
> +	rte_tel_data_start_array(child_data, RTE_TEL_BOOL_VAL);
> +
> +	struct rte_tel_data *child_data2 = rte_tel_data_alloc();
> +	rte_tel_data_start_array(child_data2, RTE_TEL_BOOL_VAL);
> +
> +	rte_tel_data_start_dict(&response_data);
> +
> +	for (i = 0; i < 10; i++) {
> +		rte_tel_data_add_array_bool(child_data, (i % 2) == 0);
> +		rte_tel_data_add_array_bool(child_data2, (i % 2) == 1);
> +	}
> +
> +	rte_tel_data_add_dict_container(&response_data, "dict_0",
> +	 child_data, 0);
> +	rte_tel_data_add_dict_container(&response_data, "dict_1",
> +	 child_data2, 0);
> +
> +	return CHECK_OUTPUT("{\"dict_0\":[true,false,true,false,true,false,true,false,true,false],"
> +		"\"dict_1\":[false,true,false,true,false,true,false,true,false,true]}");
> +}
> +
> +static int
> +test_array_with_array_bool_values(void)
> +{
> +	int i;
> +
> +	struct rte_tel_data *child_data = rte_tel_data_alloc();
> +	rte_tel_data_start_array(child_data, RTE_TEL_BOOL_VAL);
> +
> +	struct rte_tel_data *child_data2 = rte_tel_data_alloc();
> +	rte_tel_data_start_array(child_data2, RTE_TEL_BOOL_VAL);
> +
> +	rte_tel_data_start_array(&response_data, RTE_TEL_CONTAINER);
> +
> +	for (i = 0; i < 5; i++) {
> +		rte_tel_data_add_array_bool(child_data, (i % 2) == 0);
> +		rte_tel_data_add_array_bool(child_data2, (i % 2) == 1);
> +	}
> +	rte_tel_data_add_array_container(&response_data, child_data, 0);
> +	rte_tel_data_add_array_container(&response_data, child_data2, 0);
> +
> +	return CHECK_OUTPUT("[[true,false,true,false,true],[false,true,false,true,false]]");
> +}
> +
>   static int
>   test_string_char_escaping(void)
>   {
> @@ -428,15 +506,21 @@ telemetry_data_autotest(void)
>   			test_null_return,
>   			test_simple_string,
>   			test_case_array_string,
> -			test_case_array_int, test_case_array_u64,
> -			test_case_add_dict_int, test_case_add_dict_u64,
> +			test_case_array_int,
> +			test_case_array_u64,
> +			test_case_array_bool,
> +			test_case_add_dict_int,
> +			test_case_add_dict_u64,
> +			test_case_add_dict_bool,
>   			test_case_add_dict_string,
>   			test_dict_with_array_int_values,
>   			test_dict_with_array_u64_values,
> +			test_dict_with_array_bool_values,
>   			test_dict_with_array_string_values,
>   			test_dict_with_dict_values,
>   			test_array_with_array_int_values,
>   			test_array_with_array_u64_values,
> +			test_array_with_array_bool_values,
>   			test_array_with_array_string_values,
>   			test_string_char_escaping,
>   			test_array_char_escaping,
> diff --git a/lib/telemetry/rte_telemetry.h b/lib/telemetry/rte_telemetry.h
> index a0d21d6b7f..e7f6c2ae43 100644
> --- a/lib/telemetry/rte_telemetry.h
> +++ b/lib/telemetry/rte_telemetry.h
> @@ -2,6 +2,7 @@
>    * Copyright(c) 2018 Intel Corporation
>    */
>   
> +#include <stdbool.h>
>   #include <stdint.h>
>   
>   #include <rte_compat.h>
> @@ -46,6 +47,7 @@ enum rte_tel_value_type {
>   	RTE_TEL_INT_VAL,    /** a signed 32-bit int value */
>   	RTE_TEL_U64_VAL,    /** an unsigned 64-bit int value */
>   	RTE_TEL_CONTAINER, /** a container struct */
> +	RTE_TEL_BOOL_VAL,   /** a boolean value */
>   };
>   
>   /**
> @@ -155,6 +157,22 @@ int
>   rte_tel_data_add_array_container(struct rte_tel_data *d,
>   		struct rte_tel_data *val, int keep);
>   
> +/**
> + * Add a boolean to an array.
> + * The array must have been started by rte_tel_data_start_array() with
> + * RTE_TEL_BOOL_VAL as the type parameter.
> + *
> + * @param d
> + *   The data structure passed to the callback
> + * @param x
> + *   The boolean value to be returned in the array
> + * @return
> + *   0 on success, negative errno on error
> + */
> +__rte_experimental
> +int
> +rte_tel_data_add_array_bool(struct rte_tel_data *d, bool x);
> +
>   /**
>    * Add a string value to a dictionary.
>    * The dict must have been started by rte_tel_data_start_dict().
> @@ -233,6 +251,24 @@ int
>   rte_tel_data_add_dict_container(struct rte_tel_data *d, const char *name,
>   		struct rte_tel_data *val, int keep);
>   
> +/**
> + * Add a boolean value to a dictionary.
> + * The dict must have been started by rte_tel_data_start_dict().

...as RTE_TEL_BOOL_VAL as the type parameter?

> + *
> + * @param d
> + *   The data structure passed to the callback
> + * @param name
> + *   The name the value is to be stored under in the dict
> + *   Must contain only alphanumeric characters or the symbols: '_' or '/'
> + * @param val
> + *   The boolean value to be stored in the dict
> + * @return
> + *   0 on success, negative errno on error, E2BIG on string truncation of name.
> + */
> +__rte_experimental
> +int
> +rte_tel_data_add_dict_bool(struct rte_tel_data *d, const char *name, bool val);
> +
>   /**
>    * This telemetry callback is used when registering a telemetry command.
>    * It handles getting and formatting information to be returned to telemetry
> diff --git a/lib/telemetry/telemetry.c b/lib/telemetry/telemetry.c
> index 8fbb4f3060..276d0f337d 100644
> --- a/lib/telemetry/telemetry.c
> +++ b/lib/telemetry/telemetry.c
> @@ -168,7 +168,9 @@ container_to_json(const struct rte_tel_data *d, char *out_buf, size_t buf_len)
>   	unsigned int i;
>   
>   	if (d->type != RTE_TEL_DICT && d->type != RTE_TEL_ARRAY_U64 &&
> -		d->type != RTE_TEL_ARRAY_INT && d->type != RTE_TEL_ARRAY_STRING)
> +			d->type != RTE_TEL_ARRAY_INT &&
> +			d->type != RTE_TEL_ARRAY_STRING &&
> +			d->type != RTE_TEL_ARRAY_BOOL)

Use a switch for improved readability.

>   		return snprintf(out_buf, buf_len, "null");
>   
>   	used = rte_tel_json_empty_array(out_buf, buf_len, 0);
> @@ -187,6 +189,11 @@ container_to_json(const struct rte_tel_data *d, char *out_buf, size_t buf_len)
>   			used = rte_tel_json_add_array_string(out_buf,
>   				buf_len, used,
>   				d->data.array[i].sval);
> +	if (d->type == RTE_TEL_ARRAY_BOOL)

This whole section should be refactor to use a switch statement, imo.

> +		for (i = 0; i < d->data_len; i++)
> +			used = rte_tel_json_add_array_bool(out_buf,
> +				buf_len, used,
> +				d->data.array[i].boolval);
>   	if (d->type == RTE_TEL_DICT)
>   		for (i = 0; i < d->data_len; i++) {
>   			const struct tel_dict_entry *v = &d->data.dict[i];
> @@ -206,6 +213,11 @@ container_to_json(const struct rte_tel_data *d, char *out_buf, size_t buf_len)
>   						buf_len, used,
>   						v->name, v->value.u64val);
>   				break;
> +			case RTE_TEL_BOOL_VAL:
> +				used = rte_tel_json_add_obj_bool(out_buf,
> +						buf_len, used,
> +						v->name, v->value.boolval);
> +				break;
>   			case RTE_TEL_CONTAINER:
>   			{
>   				char temp[buf_len];
> @@ -273,6 +285,11 @@ output_json(const char *cmd, const struct rte_tel_data *d, int s)
>   						buf_len, used,
>   						v->name, v->value.u64val);
>   				break;
> +			case RTE_TEL_BOOL_VAL:
> +				used = rte_tel_json_add_obj_bool(cb_data_buf,
> +						buf_len, used,
> +						v->name, v->value.boolval);
> +				break;
>   			case RTE_TEL_CONTAINER:
>   			{
>   				char temp[buf_len];
> @@ -294,6 +311,7 @@ output_json(const char *cmd, const struct rte_tel_data *d, int s)
>   	case RTE_TEL_ARRAY_STRING:
>   	case RTE_TEL_ARRAY_INT:
>   	case RTE_TEL_ARRAY_U64:
> +	case RTE_TEL_ARRAY_BOOL:
>   	case RTE_TEL_ARRAY_CONTAINER:
>   		used = rte_tel_json_empty_array(cb_data_buf, buf_len, 0);
>   		for (i = 0; i < d->data_len; i++)
> @@ -310,6 +328,10 @@ output_json(const char *cmd, const struct rte_tel_data *d, int s)
>   				used = rte_tel_json_add_array_u64(cb_data_buf,
>   						buf_len, used,
>   						d->data.array[i].u64val);
> +			else if (d->type == RTE_TEL_ARRAY_BOOL)
> +				used = rte_tel_json_add_array_bool(cb_data_buf,
> +						buf_len, used,
> +						d->data.array[i].boolval);
>   			else if (d->type == RTE_TEL_ARRAY_CONTAINER) {
>   				char temp[buf_len];
>   				const struct container *rec_data =
> diff --git a/lib/telemetry/telemetry_data.c b/lib/telemetry/telemetry_data.c
> index 34366ecee3..13a7ce7034 100644
> --- a/lib/telemetry/telemetry_data.c
> +++ b/lib/telemetry/telemetry_data.c
> @@ -16,10 +16,11 @@ int
>   rte_tel_data_start_array(struct rte_tel_data *d, enum rte_tel_value_type type)
>   {
>   	enum tel_container_types array_types[] = {
> -			RTE_TEL_ARRAY_STRING, /* RTE_TEL_STRING_VAL = 0 */
> -			RTE_TEL_ARRAY_INT,    /* RTE_TEL_INT_VAL = 1 */
> -			RTE_TEL_ARRAY_U64,    /* RTE_TEL_u64_VAL = 2 */
> -			RTE_TEL_ARRAY_CONTAINER, /* RTE_TEL_CONTAINER = 3 */
> +		[RTE_TEL_STRING_VAL] = RTE_TEL_ARRAY_STRING,
> +		[RTE_TEL_INT_VAL] = RTE_TEL_ARRAY_INT,
> +		[RTE_TEL_U64_VAL] = RTE_TEL_ARRAY_U64,
> +		[RTE_TEL_CONTAINER] = RTE_TEL_ARRAY_CONTAINER,
> +		[RTE_TEL_BOOL_VAL] = RTE_TEL_ARRAY_BOOL,

Seems like a brittle construct to me. Replace this with a switch statement.

>   	};
>   	d->type = array_types[type];
>   	d->data_len = 0;
> @@ -80,6 +81,17 @@ rte_tel_data_add_array_u64(struct rte_tel_data *d, uint64_t x)
>   	return 0;
>   }
>   
> +int
> +rte_tel_data_add_array_bool(struct rte_tel_data *d, bool x)
> +{
> +	if (d->type != RTE_TEL_ARRAY_BOOL)
> +		return -EINVAL;
> +	if (d->data_len >= RTE_TEL_MAX_ARRAY_ENTRIES)
> +		return -ENOSPC;
> +	d->data.array[d->data_len++].boolval = x;
> +	return 0;
> +}
> +
>   int
>   rte_tel_data_add_array_container(struct rte_tel_data *d,
>   		struct rte_tel_data *val, int keep)
> @@ -87,7 +99,8 @@ rte_tel_data_add_array_container(struct rte_tel_data *d,
>   	if (d->type != RTE_TEL_ARRAY_CONTAINER ||
>   			(val->type != RTE_TEL_ARRAY_U64
>   			&& val->type != RTE_TEL_ARRAY_INT
> -			&& val->type != RTE_TEL_ARRAY_STRING))
> +			&& val->type != RTE_TEL_ARRAY_STRING
> +			&& val->type != RTE_TEL_ARRAY_BOOL))

Maybe the introduction of a valid_type() static function would be in 
order? Implemented by means of a (surprise!) switch statement. :)

Could be is_valid_type() and rename valid_name() us_valid_name() in the 
process.

Use in rte_tel_data_add_dict_container() as well.

>   		return -EINVAL;
>   	if (d->data_len >= RTE_TEL_MAX_ARRAY_ENTRIES)
>   		return -ENOSPC;
> @@ -179,6 +192,26 @@ rte_tel_data_add_dict_u64(struct rte_tel_data *d,
>   	return bytes < RTE_TEL_MAX_STRING_LEN ? 0 : E2BIG;
>   }
>   
> +int
> +rte_tel_data_add_dict_bool(struct rte_tel_data *d,
> +		const char *name, bool val)
> +{
> +	struct tel_dict_entry *e = &d->data.dict[d->data_len];
> +	if (d->type != RTE_TEL_DICT)
> +		return -EINVAL;
> +	if (d->data_len >= RTE_TEL_MAX_DICT_ENTRIES)
> +		return -ENOSPC;
> +
> +	if (!valid_name(name))
> +		return -EINVAL;
> +
> +	d->data_len++;
> +	e->type = RTE_TEL_BOOL_VAL;
> +	e->value.boolval = val;
> +	const size_t bytes = strlcpy(e->name, name, RTE_TEL_MAX_STRING_LEN);
> +	return bytes < RTE_TEL_MAX_STRING_LEN ? 0 : E2BIG;
> +}
> +
>   int
>   rte_tel_data_add_dict_container(struct rte_tel_data *d, const char *name,
>   		struct rte_tel_data *val, int keep)
> @@ -188,6 +221,7 @@ rte_tel_data_add_dict_container(struct rte_tel_data *d, const char *name,
>   	if (d->type != RTE_TEL_DICT || (val->type != RTE_TEL_ARRAY_U64
>   			&& val->type != RTE_TEL_ARRAY_INT
>   			&& val->type != RTE_TEL_ARRAY_STRING
> +			&& val->type != RTE_TEL_ARRAY_BOOL
>   			&& val->type != RTE_TEL_DICT))
>   		return -EINVAL;
>   	if (d->data_len >= RTE_TEL_MAX_DICT_ENTRIES)
> diff --git a/lib/telemetry/telemetry_data.h b/lib/telemetry/telemetry_data.h
> index 26aa28e72c..c840486b18 100644
> --- a/lib/telemetry/telemetry_data.h
> +++ b/lib/telemetry/telemetry_data.h
> @@ -5,6 +5,9 @@
>   #ifndef _TELEMETRY_DATA_H_
>   #define _TELEMETRY_DATA_H_
>   
> +#include <stdbool.h>
> +#include <stdint.h>
> +
>   #include "rte_telemetry.h"
>   
>   enum tel_container_types {
> @@ -15,6 +18,7 @@ enum tel_container_types {
>   	RTE_TEL_ARRAY_INT,    /** array of signed, 32-bit int values */
>   	RTE_TEL_ARRAY_U64,    /** array of unsigned 64-bit int values */
>   	RTE_TEL_ARRAY_CONTAINER, /** array of container structs */
> +	RTE_TEL_ARRAY_BOOL,   /** array of boolean values */
>   };
>   
>   struct container {
> @@ -30,6 +34,7 @@ union tel_value {
>   	char sval[RTE_TEL_MAX_STRING_LEN];
>   	int ival;
>   	uint64_t u64val;
> +	bool boolval;
>   	struct container container;
>   };
>   
> diff --git a/lib/telemetry/telemetry_json.h b/lib/telemetry/telemetry_json.h
> index e3fae7c30d..c97da97366 100644
> --- a/lib/telemetry/telemetry_json.h
> +++ b/lib/telemetry/telemetry_json.h
> @@ -7,6 +7,7 @@
>   
>   #include <inttypes.h>
>   #include <stdarg.h>
> +#include <stdbool.h>
>   #include <stdio.h>
>   #include <rte_common.h>
>   #include <rte_telemetry.h>
> @@ -159,6 +160,21 @@ rte_tel_json_add_array_u64(char *buf, const int len, const int used,
>   	return ret == 0 ? used : end + ret;
>   }
>   
> +/* Appends a boolean into the JSON array in the provided buffer. */
> +static inline int
> +rte_tel_json_add_array_bool(char *buf, const int len, const int used,
> +		bool val)
> +{
> +	int ret, end = used - 1; /* strip off final delimiter */
> +	if (used <= 2) /* assume empty, since minimum is '[]' */
> +		return __json_snprintf(buf, len, "[%s]",
> +				val ? "true" : "false");

Have "true" and "false" as #defines, and make a bool_str() helper, which 
returns the (constant) string form.

> +
> +	ret = __json_snprintf(buf + end, len - end, ",%s]",
> +			val ? "true" : "false");
> +	return ret == 0 ? used : end + ret;
> +}
> +
>   /*
>    * Add a new element with raw JSON value to the JSON array stored in the
>    * provided buffer.
> @@ -193,6 +209,24 @@ rte_tel_json_add_obj_u64(char *buf, const int len, const int used,
>   	return ret == 0 ? used : end + ret;
>   }
>   
> +/**
> + * Add a new element with boolean value to the JSON object stored in the
> + * provided buffer.
> + */
> +static inline int

I know this pattern isn't introduced in this patch, but why is this 
function in the header file?

> +rte_tel_json_add_obj_bool(char *buf, const int len, const int used,
> +		const char *name, bool val)
> +{
> +	int ret, end = used - 1;
> +	if (used <= 2) /* assume empty, since minimum is '{}' */

RTE_ASSERT() wouldn't be more helpful? The input buffer is malformed, 
correct?

Either way, the magic '2' should be a #define.

> +		return __json_snprintf(buf, len, "{\"%s\":%s}", name,
> +				val ? "true" : "false");
> +
> +	ret = __json_snprintf(buf + end, len - end, ",\"%s\":%s}",
> +			name, val ? "true" : "false");
> +	return ret == 0 ? used : end + ret;
> +}
> +

This looks like cut-and-paste. Merge into one function, parameterized by 
the start and end delimiter.

>   /**
>    * Add a new element with int value to the JSON object stored in the
>    * provided buffer.
> diff --git a/lib/telemetry/version.map b/lib/telemetry/version.map
> index 9794f9ea20..88f58d4d89 100644
> --- a/lib/telemetry/version.map
> +++ b/lib/telemetry/version.map
> @@ -19,7 +19,17 @@ DPDK_23 {
>   	local: *;
>   };
>   
> +EXPERIMENTAL {
> +	global:
> +
> +	# added in 22.11
> +	rte_tel_data_add_array_bool;
> +	rte_tel_data_add_dict_bool;
> +};
> +
>   INTERNAL {
> +	global:
> +
>   	rte_telemetry_legacy_register;
>   	rte_telemetry_init;
>   };

  reply	other threads:[~2022-10-25  9:34 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-13  7:49 [PATCH] trace: take live traces via telemetry David Marchand
2022-10-13 14:09 ` Jerin Jacob
2022-10-18 13:14 ` Bruce Richardson
2022-10-19 10:53   ` Bruce Richardson
2022-10-19 13:46     ` David Marchand
2022-10-18 14:33 ` Morten Brørup
2022-10-18 16:20   ` Bruce Richardson
2022-10-19  7:38   ` David Marchand
2022-10-19  8:21     ` Morten Brørup
2022-10-19  8:28       ` David Marchand
2022-10-25  9:00 ` [PATCH v3 0/4] Telemetry support for traces David Marchand
2022-10-25  9:00   ` [PATCH v3 1/4] telemetry: support boolean type David Marchand
2022-10-25  9:34     ` Mattias Rönnblom [this message]
2022-10-25  9:43       ` David Marchand
2022-10-25 10:38         ` Bruce Richardson
2022-10-27  8:53           ` Power, Ciara
2022-10-25  9:00   ` [PATCH v3 2/4] telemetry: extend valid command characters David Marchand
2022-10-25  9:12     ` Power, Ciara
2022-10-25  9:00   ` [PATCH v3 3/4] trace: enable trace operations via telemetry David Marchand
2022-10-25 10:18     ` Mattias Rönnblom
2022-10-25  9:00   ` [PATCH v3 4/4] trace: create new directory for each trace dump David Marchand
2022-10-25  9:41     ` Mattias Rönnblom

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