log_msg.h

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/*
 * Copyright (c) 2021 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef ZEPHYR_INCLUDE_LOGGING_LOG_MSG_H_
#define ZEPHYR_INCLUDE_LOGGING_LOG_MSG_H_
 
#include <zephyr/logging/log_instance.h>
#include <zephyr/sys/mpsc_packet.h>
#include <zephyr/sys/cbprintf.h>
#include <zephyr/sys/atomic.h>
#include <zephyr/sys/iterable_sections.h>
#include <zephyr/sys/util.h>
#include <string.h>
#include <zephyr/toolchain.h>
 
#ifdef __GNUC__
#ifndef alloca
#define alloca __builtin_alloca
#endif
#else
#include <alloca.h>
#endif
 
#ifdef __cplusplus
extern "C" {
#endif
 
#define LOG_MSG_DEBUG 0
#define LOG_MSG_DBG(...) IF_ENABLED(LOG_MSG_DEBUG, (printk(__VA_ARGS__)))
 
#ifdef CONFIG_LOG_TIMESTAMP_64BIT
typedef uint64_t log_timestamp_t;
#else
typedef uint32_t log_timestamp_t;
#endif
 
#define Z_LOG_MSG_LOG 0
 
#define Z_LOG_MSG_PACKAGE_BITS 11
 
#define Z_LOG_MSG_MAX_PACKAGE BIT_MASK(Z_LOG_MSG_PACKAGE_BITS)
 
#define LOG_MSG_GENERIC_HDR \
        MPSC_PBUF_HDR;\
        uint32_t type:1
 
struct log_msg_desc {
        LOG_MSG_GENERIC_HDR;
        uint32_t domain:3;
        uint32_t level:3;
        uint32_t package_len:Z_LOG_MSG_PACKAGE_BITS;
        uint32_t data_len:12;
};
 
union log_msg_source {
        const struct log_source_const_data *fixed;
        struct log_source_dynamic_data *dynamic;
        void *raw;
};
 
struct log_msg_hdr {
        struct log_msg_desc desc;
/* Attempting to keep best alignment. When address is 64 bit and timestamp 32
 * swap the order to have 16 byte header instead of 24 byte.
 */
#if (INTPTR_MAX > INT32_MAX) && !CONFIG_LOG_TIMESTAMP_64BIT
        log_timestamp_t timestamp;
        const void *source;
#else
        const void *source;
        log_timestamp_t timestamp;
#endif
};
 
/* Messages are aligned to alignment required by cbprintf package. */
#define Z_LOG_MSG_ALIGNMENT CBPRINTF_PACKAGE_ALIGNMENT
 
#define Z_LOG_MSG_PADDING \
        ((sizeof(struct log_msg_hdr) % Z_LOG_MSG_ALIGNMENT) > 0 ? \
        (Z_LOG_MSG_ALIGNMENT - (sizeof(struct log_msg_hdr) % Z_LOG_MSG_ALIGNMENT)) : \
                0)
 
struct log_msg {
        struct log_msg_hdr hdr;
        /* Adding padding to ensure that cbprintf package that follows is
         * properly aligned.
         */
        uint8_t padding[Z_LOG_MSG_PADDING];
        uint8_t data[];
};
 
BUILD_ASSERT(sizeof(struct log_msg) % Z_LOG_MSG_ALIGNMENT == 0,
             "Log msg size must aligned");
struct log_msg_generic_hdr {
        LOG_MSG_GENERIC_HDR;
};
 
union log_msg_generic {
        union mpsc_pbuf_generic buf;
        struct log_msg_generic_hdr generic;
        struct log_msg log;
};
 
enum z_log_msg_mode {
        /* Runtime mode is least efficient but supports all cases thus it is
         * treated as a fallback method when others cannot be used.
         */
        Z_LOG_MSG_MODE_RUNTIME,
        /* Mode creates statically a string package on stack and calls a
         * function for creating a message. It takes code size than
         * Z_LOG_MSG_MODE_ZERO_COPY but is a bit slower.
         */
        Z_LOG_MSG_MODE_FROM_STACK,
 
        /* Mode calculates size of the message and allocates it and writes
         * directly to the message space. It is the fastest method but requires
         * more code size.
         */
        Z_LOG_MSG_MODE_ZERO_COPY,
};
 
#define Z_LOG_MSG_DESC_INITIALIZER(_domain_id, _level, _plen, _dlen) \
{ \
        .valid = 0, \
        .busy = 0, \
        .type = Z_LOG_MSG_LOG, \
        .domain = _domain_id, \
        .level = _level, \
        .package_len = _plen, \
        .data_len = _dlen, \
}
 
#define Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt) \
        (CBPRINTF_PACKAGE_FIRST_RO_STR_CNT(_cstr_cnt) | \
        (IS_ENABLED(CONFIG_LOG_MSG_APPEND_RO_STRING_LOC) ? \
         CBPRINTF_PACKAGE_ADD_STRING_IDXS : 0))
 
#ifdef CONFIG_LOG_USE_VLA
#define Z_LOG_MSG_ON_STACK_ALLOC(ptr, len) \
        long long _ll_buf[DIV_ROUND_UP(len, sizeof(long long))]; \
        long double _ld_buf[DIV_ROUND_UP(len, sizeof(long double))]; \
        ptr = (sizeof(long double) == Z_LOG_MSG_ALIGNMENT) ? \
                        (struct log_msg *)_ld_buf : (struct log_msg *)_ll_buf; \
        if (IS_ENABLED(CONFIG_LOG_TEST_CLEAR_MESSAGE_SPACE)) { \
                /* During test fill with 0's to simplify message comparison */ \
                memset(ptr, 0, len); \
        }
#else /* Z_LOG_MSG_USE_VLA */
/* When VLA cannot be used we need to trick compiler a bit and create multiple
 * fixed size arrays and take the smallest one that will fit the message.
 * Compiler will remove unused arrays and stack usage will be kept similar
 * to vla case, rounded to the size of the used buffer.
 */
#define Z_LOG_MSG_ON_STACK_ALLOC(ptr, len) \
        long long _ll_buf32[32 / sizeof(long long)]; \
        long long _ll_buf48[48 / sizeof(long long)]; \
        long long _ll_buf64[64 / sizeof(long long)]; \
        long long _ll_buf128[128 / sizeof(long long)]; \
        long long _ll_buf256[256 / sizeof(long long)]; \
        long double _ld_buf32[32 / sizeof(long double)]; \
        long double _ld_buf48[48 / sizeof(long double)]; \
        long double _ld_buf64[64 / sizeof(long double)]; \
        long double _ld_buf128[128 / sizeof(long double)]; \
        long double _ld_buf256[256 / sizeof(long double)]; \
        if (sizeof(long double) == Z_LOG_MSG_ALIGNMENT) { \
                ptr = (len > 128) ? (struct log_msg *)_ld_buf256 : \
                        ((len > 64) ? (struct log_msg *)_ld_buf128 : \
                        ((len > 48) ? (struct log_msg *)_ld_buf64 : \
                        ((len > 32) ? (struct log_msg *)_ld_buf48 : \
                                      (struct log_msg *)_ld_buf32)));\
        } else { \
                ptr = (len > 128) ? (struct log_msg *)_ll_buf256 : \
                        ((len > 64) ? (struct log_msg *)_ll_buf128 : \
                        ((len > 48) ? (struct log_msg *)_ll_buf64 : \
                        ((len > 32) ? (struct log_msg *)_ll_buf48 : \
                                      (struct log_msg *)_ll_buf32)));\
        } \
        if (IS_ENABLED(CONFIG_LOG_TEST_CLEAR_MESSAGE_SPACE)) { \
                /* During test fill with 0's to simplify message comparison */ \
                memset(ptr, 0, len); \
        }
#endif /* Z_LOG_MSG_USE_VLA */
 
#define Z_LOG_MSG_ALIGN_OFFSET \
        offsetof(struct log_msg, data)
 
#define Z_LOG_MSG_LEN(pkg_len, data_len) \
        (offsetof(struct log_msg, data) + pkg_len + (data_len))
 
#define Z_LOG_MSG_ALIGNED_WLEN(pkg_len, data_len) \
        DIV_ROUND_UP(ROUND_UP(Z_LOG_MSG_LEN(pkg_len, data_len), \
                                  Z_LOG_MSG_ALIGNMENT), \
                         sizeof(uint32_t))
 
/*
 * With Zephyr SDK 0.14.2, aarch64-zephyr-elf-gcc (10.3.0) fails to ensure $sp
 * is below the active memory during message construction. As a result,
 * interrupts happening in the middle of that process can end up smashing active
 * data and causing a logging fault. Work around this by inserting a compiler
 * barrier after the allocation and before any use to make sure GCC moves the
 * stack pointer soon enough
 */
 
#define Z_LOG_ARM64_VLA_PROTECT() compiler_barrier()
 
#define Z_LOG_MSG_STACK_CREATE(_cstr_cnt, _domain_id, _source, _level, _data, _dlen, ...) \
do { \
        int _plen; \
        uint32_t _options = Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt) | \
                          CBPRINTF_PACKAGE_ADD_RW_STR_POS; \
        if (GET_ARG_N(1, __VA_ARGS__) == NULL) { \
                _plen = 0; \
        } else { \
                CBPRINTF_STATIC_PACKAGE(NULL, 0, _plen, Z_LOG_MSG_ALIGN_OFFSET, _options, \
                                        __VA_ARGS__); \
        } \
        struct log_msg *_msg; \
        Z_LOG_MSG_ON_STACK_ALLOC(_msg, Z_LOG_MSG_LEN(_plen, 0)); \
        Z_LOG_ARM64_VLA_PROTECT(); \
        if (_plen != 0) { \
                CBPRINTF_STATIC_PACKAGE(_msg->data, _plen, \
                                        _plen, Z_LOG_MSG_ALIGN_OFFSET, _options, \
                                        __VA_ARGS__);\
        } \
        struct log_msg_desc _desc = \
                Z_LOG_MSG_DESC_INITIALIZER(_domain_id, _level, \
                                           (uint32_t)_plen, _dlen); \
        LOG_MSG_DBG("creating message on stack: package len: %d, data len: %d\n", \
                        _plen, (int)(_dlen)); \
        z_log_msg_static_create((void *)_source, _desc, _msg->data, _data); \
} while (false)
 
#ifdef CONFIG_LOG_SPEED
#define Z_LOG_MSG_SIMPLE_CREATE(_cstr_cnt, _domain_id, _source, _level, ...) do { \
        int _plen; \
        CBPRINTF_STATIC_PACKAGE(NULL, 0, _plen, Z_LOG_MSG_ALIGN_OFFSET, \
                                Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt), \
                                __VA_ARGS__); \
        size_t _msg_wlen = Z_LOG_MSG_ALIGNED_WLEN(_plen, 0); \
        struct log_msg *_msg = z_log_msg_alloc(_msg_wlen); \
        struct log_msg_desc _desc = \
                Z_LOG_MSG_DESC_INITIALIZER(_domain_id, _level, (uint32_t)_plen, 0); \
        LOG_MSG_DBG("creating message zero copy: package len: %d, msg: %p\n", \
                        _plen, _msg); \
        if (_msg) { \
                CBPRINTF_STATIC_PACKAGE(_msg->data, _plen, _plen, \
                                        Z_LOG_MSG_ALIGN_OFFSET, \
                                        Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt), \
                                        __VA_ARGS__); \
        } \
        z_log_msg_finalize(_msg, (void *)_source, _desc, NULL); \
} while (false)
#else
/* Alternative empty macro created to speed up compilation when LOG_SPEED is
 * disabled (default).
 */
#define Z_LOG_MSG_SIMPLE_CREATE(...)
#endif
 
/* Macro handles case when local variable with log message string is created. It
 * replaces original string literal with that variable.
 */
#define Z_LOG_FMT_ARGS_2(_name, ...) \
        COND_CODE_1(CONFIG_LOG_FMT_SECTION, \
                (COND_CODE_0(NUM_VA_ARGS_LESS_1(__VA_ARGS__), \
                   (_name), (_name, GET_ARGS_LESS_N(1, __VA_ARGS__)))), \
                (__VA_ARGS__))
 
#define Z_LOG_FMT_ARGS(_name, ...) \
        COND_CODE_0(NUM_VA_ARGS_LESS_1(_, ##__VA_ARGS__), \
                (NULL), \
                (Z_LOG_FMT_ARGS_2(_name, ##__VA_ARGS__)))
 
#if defined(CONFIG_LOG_USE_TAGGED_ARGUMENTS)
 
#define Z_LOG_FMT_TAGGED_ARGS_2(_name, ...) \
        COND_CODE_1(CONFIG_LOG_FMT_SECTION, \
                    (_name, Z_CBPRINTF_TAGGED_ARGS(NUM_VA_ARGS_LESS_1(__VA_ARGS__), \
                                                   GET_ARGS_LESS_N(1, __VA_ARGS__))), \
                    (GET_ARG_N(1, __VA_ARGS__), \
                     Z_CBPRINTF_TAGGED_ARGS(NUM_VA_ARGS_LESS_1(__VA_ARGS__), \
                                            GET_ARGS_LESS_N(1, __VA_ARGS__))))
 
#define Z_LOG_FMT_TAGGED_ARGS(_name, ...) \
        COND_CODE_0(NUM_VA_ARGS_LESS_1(_, ##__VA_ARGS__), \
                (Z_CBPRINTF_TAGGED_ARGS(0)), \
                (Z_LOG_FMT_TAGGED_ARGS_2(_name, ##__VA_ARGS__)))
 
#define Z_LOG_FMT_RUNTIME_ARGS(...) \
        Z_LOG_FMT_TAGGED_ARGS(__VA_ARGS__)
 
#else
 
#define Z_LOG_FMT_RUNTIME_ARGS(...) \
        Z_LOG_FMT_ARGS(__VA_ARGS__)
 
#endif /* CONFIG_LOG_USE_TAGGED_ARGUMENTS */
 
/* Macro handles case when there is no string provided, in that case variable
 * is not created.
 */
#define Z_LOG_MSG_STR_VAR_IN_SECTION(_name, ...) \
        COND_CODE_0(NUM_VA_ARGS_LESS_1(_, ##__VA_ARGS__), \
                    (/* No args provided, no variable */), \
                    (static const char _name[] \
                     __in_section(_log_strings, static, _CONCAT(_name, _)) __used __noasan = \
                        GET_ARG_N(1, __VA_ARGS__);))
 
#define Z_LOG_MSG_STR_VAR(_name, ...) \
        IF_ENABLED(CONFIG_LOG_FMT_SECTION, \
                   (Z_LOG_MSG_STR_VAR_IN_SECTION(_name, ##__VA_ARGS__)))
 
#if defined(CONFIG_LOG_ALWAYS_RUNTIME) || \
        (!defined(CONFIG_LOG) && \
                (!TOOLCHAIN_HAS_PRAGMA_DIAG || !TOOLCHAIN_HAS_C_AUTO_TYPE))
#define Z_LOG_MSG_CREATE2(_try_0cpy, _mode,  _cstr_cnt, _domain_id, _source,\
                          _level, _data, _dlen, ...) \
do {\
        Z_LOG_MSG_STR_VAR(_fmt, ##__VA_ARGS__) \
        z_log_msg_runtime_create(_domain_id, (void *)_source, \
                                  _level, (uint8_t *)_data, _dlen,\
                                  Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt) | \
                                  (IS_ENABLED(CONFIG_LOG_USE_TAGGED_ARGUMENTS) ? \
                                   CBPRINTF_PACKAGE_ARGS_ARE_TAGGED : 0), \
                                  Z_LOG_FMT_RUNTIME_ARGS(_fmt, ##__VA_ARGS__));\
        _mode = Z_LOG_MSG_MODE_RUNTIME; \
} while (false)
#else /* CONFIG_LOG_ALWAYS_RUNTIME */
#define Z_LOG_MSG_CREATE3(_try_0cpy, _mode,  _cstr_cnt, _domain_id, _source,\
                          _level, _data, _dlen, ...) \
do { \
        Z_LOG_MSG_STR_VAR(_fmt, ##__VA_ARGS__); \
        bool has_rw_str = CBPRINTF_MUST_RUNTIME_PACKAGE( \
                                        Z_LOG_MSG_CBPRINTF_FLAGS(_cstr_cnt), \
                                        __VA_ARGS__); \
        if (IS_ENABLED(CONFIG_LOG_SPEED) && _try_0cpy && ((_dlen) == 0) && !has_rw_str) {\
                LOG_MSG_DBG("create zero-copy message\n");\
                Z_LOG_MSG_SIMPLE_CREATE(_cstr_cnt, _domain_id, _source, \
                                        _level, Z_LOG_FMT_ARGS(_fmt, ##__VA_ARGS__)); \
                _mode = Z_LOG_MSG_MODE_ZERO_COPY; \
        } else { \
                LOG_MSG_DBG("create on stack message\n");\
                Z_LOG_MSG_STACK_CREATE(_cstr_cnt, _domain_id, _source, _level, _data, \
                                        _dlen, Z_LOG_FMT_ARGS(_fmt, ##__VA_ARGS__)); \
                _mode = Z_LOG_MSG_MODE_FROM_STACK; \
        } \
        (void)_mode; \
} while (false)
 
#if defined(__cplusplus)
#define Z_AUTO_TYPE auto
#else
#define Z_AUTO_TYPE __auto_type
#endif
 
/* Macro for getting name of a local variable with the exception of the first argument
 * which is a formatted string in log message.
 */
#define Z_LOG_LOCAL_ARG_NAME(idx, arg) COND_CODE_0(idx, (arg), (_v##idx))
 
/* Create local variable from input variable (expect for the first (fmt) argument). */
#define Z_LOG_LOCAL_ARG_CREATE(idx, arg) \
        COND_CODE_0(idx, (), (Z_AUTO_TYPE Z_LOG_LOCAL_ARG_NAME(idx, arg) = (arg) + 0))
 
/* First level of processing creates stack variables to be passed for further processing.
 * This is done to prevent multiple evaluations of input arguments (in case argument
 * evaluation has side effects, e.g. it is a non-pure function call).
 */
#define Z_LOG_MSG_CREATE2(_try_0cpy, _mode, _cstr_cnt,  _domain_id, _source, \
                           _level, _data, _dlen, ...) \
do { \
        _Pragma("GCC diagnostic push") \
        _Pragma("GCC diagnostic ignored \"-Wpointer-arith\"") \
        FOR_EACH_IDX(Z_LOG_LOCAL_ARG_CREATE, (;), __VA_ARGS__); \
        _Pragma("GCC diagnostic pop") \
        Z_LOG_MSG_CREATE3(_try_0cpy, _mode,  _cstr_cnt, _domain_id, _source,\
                           _level, _data, _dlen, \
                           FOR_EACH_IDX(Z_LOG_LOCAL_ARG_NAME, (,), __VA_ARGS__)); \
} while (false)
#endif /* CONFIG_LOG_ALWAYS_RUNTIME ||
        * (!LOG && (!TOOLCHAIN_HAS_PRAGMA_DIAG || !TOOLCHAIN_HAS_C_AUTO_TYPE))
        */
 
 
#define Z_LOG_MSG_CREATE(_try_0cpy, _mode,  _domain_id, _source,\
                          _level, _data, _dlen, ...) \
        Z_LOG_MSG_CREATE2(_try_0cpy, _mode, UTIL_CAT(Z_LOG_FUNC_PREFIX_, _level), \
                           _domain_id, _source, _level, _data, _dlen, \
                           Z_LOG_STR(_level, __VA_ARGS__))
 
struct log_msg *z_log_msg_alloc(uint32_t wlen);
 
void z_log_msg_finalize(struct log_msg *msg, const void *source,
                         const struct log_msg_desc desc, const void *data);
 
__syscall void z_log_msg_static_create(const void *source,
                                        const struct log_msg_desc desc,
                                        uint8_t *package, const void *data);
 
__syscall void z_log_msg_runtime_vcreate(uint8_t domain_id, const void *source,
                                          uint8_t level, const void *data,
                                          size_t dlen, uint32_t package_flags,
                                          const char *fmt,
                                          va_list ap);
 
static inline void z_log_msg_runtime_create(uint8_t domain_id,
                                             const void *source,
                                             uint8_t level, const void *data,
                                             size_t dlen, uint32_t package_flags,
                                             const char *fmt, ...)
{
        va_list ap;
 
        va_start(ap, fmt);
        z_log_msg_runtime_vcreate(domain_id, source, level,
                                   data, dlen, package_flags, fmt, ap);
        va_end(ap);
}
 
static inline bool z_log_item_is_msg(const union log_msg_generic *msg)
{
        return msg->generic.type == Z_LOG_MSG_LOG;
}
 
static inline uint32_t log_msg_get_total_wlen(const struct log_msg_desc desc)
{
        return Z_LOG_MSG_ALIGNED_WLEN(desc.package_len, desc.data_len);
}
 
static inline uint32_t log_msg_generic_get_wlen(const union mpsc_pbuf_generic *item)
{
        const union log_msg_generic *generic_msg = (const union log_msg_generic *)item;
 
        if (z_log_item_is_msg(generic_msg)) {
                const struct log_msg *msg = (const struct log_msg *)generic_msg;
 
                return log_msg_get_total_wlen(msg->hdr.desc);
        }
 
        return 0;
}
 
static inline uint8_t log_msg_get_domain(struct log_msg *msg)
{
        return msg->hdr.desc.domain;
}
 
static inline uint8_t log_msg_get_level(struct log_msg *msg)
{
        return msg->hdr.desc.level;
}
 
static inline const void *log_msg_get_source(struct log_msg *msg)
{
        return msg->hdr.source;
}
 
static inline log_timestamp_t log_msg_get_timestamp(struct log_msg *msg)
{
        return msg->hdr.timestamp;
}
 
static inline uint8_t *log_msg_get_data(struct log_msg *msg, size_t *len)
{
        *len = msg->hdr.desc.data_len;
 
        return msg->data + msg->hdr.desc.package_len;
}
 
static inline uint8_t *log_msg_get_package(struct log_msg *msg, size_t *len)
{
        *len = msg->hdr.desc.package_len;
 
        return msg->data;
}
 
#include <syscalls/log_msg.h>
 
#ifdef __cplusplus
}
#endif
 
#endif /* ZEPHYR_INCLUDE_LOGGING_LOG_MSG_H_ */