Re: [U-Boot] [PATCH v3 07/14] log: Add an implemention of logging

On Mon, 20 Nov 2017 15:33:28 -0700 Simon Glass sjg@chromium.org wrote:

Add the logging header file and implementation with some configuration options to control it.

Despite one question -

Reviewed-by: Lukasz Majewski lukma@denx.de

Signed-off-by: Simon Glass sjg@chromium.org

Changes in v3: None Changes in v2:

• Add a comment as to why CONFIG_LOG_MAX_LEVEL is not defined
• Drop MAINTAINERS entries for files not added by this patch
• Drop the use of 'continue' in the macro
• Fix LOG_SPL_MAX_LEVEL typo (should be SPL_LOG_MAX_LEVEL)
• Fix up bad use of #if CONFIG_VAL() - use #ifdef instead
• Line up log levels with Linux

MAINTAINERS | 7 ++ common/Kconfig | 56 +++++++++ common/Makefile | 1 + common/log.c | 244 ++++++++++++++++++++++++++++++++++++++ include/asm-generic/global_data.h | 5 + include/log.h | 235 ++++++++++++++++++++++++++++++++++++ 6 files changed, 548 insertions(+) create mode 100644 common/log.c

diff --git a/MAINTAINERS b/MAINTAINERS index b167b028ecf..6814c2fc566 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -291,6 +291,13 @@ S: Maintained T: git git://git.denx.de/u-boot-i2c.git F: drivers/i2c/

+LOGGING +M: Simon Glass sjg@chromium.org +S: Maintained +T: git git://git.denx.de/u-boot.git +F: common/log.c +F: cmd/log.c

MICROBLAZE M: Michal Simek monstr@monstr.eu S: Maintained diff --git a/common/Kconfig b/common/Kconfig index c50d6ebb2ad..9747443feb2 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -420,6 +420,62 @@ config SYS_STDIO_DEREGISTER

endmenu

+menu "Logging"

+config LOG

• bool "Enable logging support"
• help

•  This enables support for logging of status and debug
  

messages. These

•  can be displayed on the console, recorded in a memory
  

buffer, or

•  discarded if not needed. Logging supports various
  

categories and

•  levels of severity.
  

+config SPL_LOG

• bool "Enable logging support in SPL"
• help

•  This enables support for logging of status and debug
  

messages. These

•  can be displayed on the console, recorded in a memory
  

buffer, or

•  discarded if not needed. Logging supports various
  

categories and

•  levels of severity.
  

+config LOG_MAX_LEVEL

• int "Maximum log level to record"
• depends on LOG
• default 5
• help

•  This selects the maximum log level that will be recorded.
  

Any value

•  higher than this will be ignored. If possible log
  

statements below

•  this level will be discarded at build time. Levels:
  

•    0 - panic
  

•    1 - critical
  

•    2 - error
  

•    3 - warning
  

•    4 - note
  

•    5 - info
  

•    6 - detail
  

•    7 - debug
  

+config SPL_LOG_MAX_LEVEL

• int "Maximum log level to record in SPL"
• depends on SPL_LOG
• default 3
• help

•  This selects the maximum log level that will be recorded.
  

Any value

•  higher than this will be ignored. If possible log
  

statements below

•  this level will be discarded at build time. Levels:
  

•    0 - panic
  

•    1 - critical
  

•    2 - error
  

•    3 - warning
  

•    4 - note
  

•    5 - info
  

•    6 - detail
  

•    7 - debug
  

+endmenu

config DEFAULT_FDT_FILE string "Default fdt file" help diff --git a/common/Makefile b/common/Makefile index cec506fe3e1..f4b632761fa 100644 --- a/common/Makefile +++ b/common/Makefile @@ -128,5 +128,6 @@ obj-y += cli.o obj-$(CONFIG_FSL_DDR_INTERACTIVE) += cli_simple.o cli_readline.o obj-$(CONFIG_CMD_DFU) += dfu.o obj-y += command.o +obj-$(CONFIG_$(SPL_)LOG) += log.o obj-y += s_record.o obj-y += xyzModem.o diff --git a/common/log.c b/common/log.c new file mode 100644 index 00000000000..a7d9a548f2a --- /dev/null +++ b/common/log.c @@ -0,0 +1,244 @@ +/*

• • Logging support
• • Copyright (c) 2017 Google, Inc
• • Written by Simon Glass sjg@chromium.org
• • SPDX-License-Identifier: GPL-2.0+
• */

+#include <common.h> +#include <log.h> +#include <malloc.h>

+DECLARE_GLOBAL_DATA_PTR;

+static struct log_device *log_device_find_by_name(const char *drv_name) +{

• struct log_device *ldev;
• list_for_each_entry(ldev, &gd->log_head, sibling_node) {

• if (!strcmp(drv_name, ldev->drv->name))
  

• 	return ldev;
  

• }
• return NULL;

+}

+/**

• • log_has_cat() - check if a log category exists within a list
• • @cat_list: List of categories to check, at most

LOGF_MAX_CATEGORIES entries

• • long, terminated by LC_END if fewer
• • @cat: Category to search for
• • @return true if @cat is in @cat_list, else false
• */

+static bool log_has_cat(enum log_category_t cat_list[], enum log_category_t cat) +{

• int i;
• for (i = 0; i < LOGF_MAX_CATEGORIES && cat_list[i] !=

LOGC_END; i++) {

• if (cat_list[i] == cat)
  

• 	return true;
  

• }
• return false;

+}

+/**

• • log_has_file() - check if a file is with a list
• • @file_list: List of files to check, separated by comma
• • @file: File to check for. This string is matched against the end

of each

• • file in the list, i.e. ignoring any preceeding path. The

list is

• • intended to consist of relative pathnames, e.g.

common/main.c,cmd/log.c

• • @return true if @file is in @file_list, else false
• */

+static bool log_has_file(const char *file_list, const char *file) +{

• int file_len = strlen(file);
• const char *s, *p;
• int substr_len;
• for (s = file_list; *s; s = p + (*p != '\0')) {

• p = strchrnul(s, ',');
  

• substr_len = p - s;
  

• if (file_len >= substr_len &&
  

•     !strncmp(file + file_len - substr_len, s,
  

substr_len))

• 	return true;
  

• }
• return false;

+}

+/**

• • log_passes_filters() - check if a log record passes the filters

for a device

• • @ldev: Log device to check
• • @rec: Log record to check
• • @return true if @rec is not blocked by the filters in @ldev,

false if it is

• */

+static bool log_passes_filters(struct log_device *ldev, struct log_rec *rec) +{

• struct log_filter *filt;
• /* If there are no filters, filter on the default log level

*/

• if (list_empty(&ldev->filter_head)) {

• if (rec->level > gd->default_log_level)
  

• 	return false;
  

• return true;
  

• }
• list_for_each_entry(filt, &ldev->filter_head, sibling_node) {

• if (rec->level > filt->max_level)
  

• 	continue;
  

• if ((filt->flags & LOGFF_HAS_CAT) &&
  

•     !log_has_cat(filt->cat_list, rec->cat))
  

• 	continue;
  

• if (filt->file_list &&
  

•     !log_has_file(filt->file_list, rec->file))
  

• 	continue;
  

• return true;
  

• }
• return false;

+}

+/**

• • log_dispatch() - Send a log record to all log devices for

processing

• • The log record is sent to each log device in turn, skipping those

which have

• • filters which block the record
• • @rec: Log record to dispatch
• • @return 0 (meaning success)
• */

+static int log_dispatch(struct log_rec *rec) +{

• struct log_device *ldev;
• list_for_each_entry(ldev, &gd->log_head, sibling_node) {

• if (log_passes_filters(ldev, rec))
  

• 	ldev->drv->emit(ldev, rec);
  

• }
• return 0;

+}

+int _log(enum log_category_t cat, enum log_level_t level, const char *file,

• int line, const char *func, const char *fmt, ...)
  

+{

• char buf[CONFIG_SYS_CBSIZE];
• struct log_rec rec;
• va_list args;
• rec.cat = cat;
• rec.level = level;
• rec.file = file;
• rec.line = line;
• rec.func = func;
• va_start(args, fmt);
• vsnprintf(buf, sizeof(buf), fmt, args);
• va_end(args);
• rec.msg = buf;
• if (!gd || !(gd->flags & GD_FLG_LOG_READY)) {

• if (gd)
  

• 	gd->log_drop_count++;
  

• return -ENOSYS;
  

• }
• log_dispatch(&rec);
• return 0;

+}

+int log_add_filter(const char *drv_name, enum log_category_t cat_list[],

•    enum log_level_t max_level, const char *file_list)
  

+{

• struct log_filter *filt;
• struct log_device *ldev;
• int i;
• ldev = log_device_find_by_name(drv_name);
• if (!ldev)

• return -ENOENT;
  

• filt = (struct log_filter *)calloc(1, sizeof(*filt));
• if (!filt)

• return -ENOMEM;
  

• if (cat_list) {

• filt->flags |= LOGFF_HAS_CAT;
  

• for (i = 0; ; i++) {
  

^^^^ - I suppose that this is "true" Does it comply with any standard (is it the undefined behaviour?)

• 	if (i == ARRAY_SIZE(filt->cat_list))
  

• 		return -ENOSPC;
  

• 	filt->cat_list[i] = cat_list[i];
  

• 	if (cat_list[i] == LOGC_END)
  

• 		break;
  

• }
  

• }
• filt->max_level = max_level;
• if (file_list) {

• filt->file_list = strdup(file_list);
  

• if (!filt->file_list)
  

• 	goto nomem;
  

• }
• filt->filter_num = ldev->next_filter_num++;
• list_add_tail(&filt->sibling_node, &ldev->filter_head);
• return filt->filter_num;

+nomem:

• free(filt);
• return -ENOMEM;

+}

+int log_remove_filter(const char *drv_name, int filter_num) +{

• struct log_filter *filt;
• struct log_device *ldev;
• ldev = log_device_find_by_name(drv_name);
• if (!ldev)

• return -ENOENT;
  

• list_for_each_entry(filt, &ldev->filter_head, sibling_node) {

• if (filt->filter_num == filter_num) {
  

• 	list_del(&filt->sibling_node);
  

• 	free(filt);
  

• 	return 0;
  

• }
  

• }
• return -ENOENT;

+}

+int log_init(void) +{

• struct log_driver *drv = ll_entry_start(struct log_driver,

log_driver);

• const int count = ll_entry_count(struct log_driver,

log_driver);

• struct log_driver *end = drv + count;
• /*

• * We cannot add runtime data to the driver since it is
  

likely stored

• * in rodata. Instead, set up a 'device' corresponding to
  

each driver.

• * We only support having a single device.
  

• */
  

• INIT_LIST_HEAD((struct list_head *)&gd->log_head);
• while (drv < end) {

• struct log_device *ldev;
  

• ldev = calloc(1, sizeof(*ldev));
  

• if (!ldev) {
  

• 	debug("%s: Cannot allocate memory\n",
  

__func__);

• 	return -ENOMEM;
  

• }
  

• INIT_LIST_HEAD(&ldev->filter_head);
  

• ldev->drv = drv;
  

• list_add_tail(&ldev->sibling_node,
  

• 	      (struct list_head *)&gd->log_head);
  

• drv++;
  

• }
• gd->default_log_level = LOGL_INFO;
• return 0;

+} diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h index 79197acfa42..77755dbb068 100644 --- a/include/asm-generic/global_data.h +++ b/include/asm-generic/global_data.h @@ -114,6 +114,11 @@ typedef struct global_data { struct bootstage_data *bootstage; /* Bootstage information */ struct bootstage_data *new_bootstage; /* Relocated bootstage info */ #endif +#ifdef CONFIG_LOG

• int log_drop_count; /* Number of dropped log

messages */

• int default_log_level; /* For devices with no

filters */

• struct list_head log_head; /* List of struct

log_device */ +#endif } gd_t; #endif

diff --git a/include/log.h b/include/log.h index 08ad44cf497..5dced16880b 100644 --- a/include/log.h +++ b/include/log.h @@ -10,6 +10,87 @@ #ifndef __LOG_H #define __LOG_H

+#include <dm/uclass-id.h> +#include <linux/list.h>

+/** Log levels supported, ranging from most to least important */ +enum log_level_t {

• LOGL_EMERG = 0, /*U-Boot is unstable */
• LOGL_ALERT, /* Action must be taken

immediately */

• LOGL_CRIT, /* Critical conditions */
• LOGL_ERR, /* Error that prevents something

from working */

• LOGL_WARNING, /* Warning may prevent optimial

operation */

• LOGL_NOTICE, /* Normal but significant

condition, printf() */

• LOGL_INFO, /* General information message */
• LOGL_DEBUG, /* Basic debug-level message */
• LOGL_DEBUG_CONTENT, /* Debug message showing full

message content */

• LOGL_DEBUG_IO, /* Debug message showing

hardware I/O access */ +

• LOGL_COUNT,
• LOGL_FIRST = LOGL_EMERG,
• LOGL_MAX = LOGL_DEBUG,

+};

+/**

• • Log categories supported. Most of these correspond to uclasses

(i.e.

• • enum uclass_id) but there are also some more generic categories
• */

+enum log_category_t {

• LOGC_FIRST = 0, /* First part mirrors UCLASS_... */
• LOGC_NONE = UCLASS_COUNT,
• LOGC_ARCH,
• LOGC_BOARD,
• LOGC_CORE,
• LOGC_DT,
• LOGC_COUNT,
• LOGC_END,

+};

+/**

• • _log() - Internal function to emit a new log record
• • @cat: Category of log record (indicating which subsystem

generated it)

• • @level: Level of log record (indicating its severity)
• • @file: File name of file where log record was generated
• • @line: Line number in file where log record was generated
• • @func: Function where log record was generated
• • @fmt: printf() format string for log record
• • @...: Optional parameters, according to the format string @fmt
• • @return 0 if log record was emitted, -ve on error
• */

+int _log(enum log_category_t cat, enum log_level_t level, const char *file,

• int line, const char *func, const char *fmt, ...);
  

+/* Define this at the top of a file to add a prefix to debug messages */ +#ifndef pr_fmt +#define pr_fmt(fmt) fmt +#endif

+/* Use a default category if this file does not supply one */ +#ifndef LOG_CATEGORY +#define LOG_CATEGORY LOGC_NONE +#endif

+/*

• • This header may be including when CONFIG_LOG is disabled, in

which case

• • CONFIG_LOG_MAX_LEVEL is not defined. Add a check for this.
• */

+#if CONFIG_IS_ENABLED(LOG) +#define _LOG_MAX_LEVEL CONFIG_VAL(LOG_MAX_LEVEL) +#else +#define _LOG_MAX_LEVEL LOGL_INFO +#endif

+/* Emit a log record if the level is less that the maximum */ +#define log(_cat, _level, _fmt, _args...) ({ \

• int _l = _level; \
• if (_l <= _LOG_MAX_LEVEL) \

• _log(_cat, _l, __FILE__, __LINE__, __func__, \
  

•      pr_fmt(_fmt), ##_args); \
  

• })

#ifdef DEBUG #define _DEBUG 1 #else @@ -22,6 +103,16 @@ #define _SPL_BUILD 0 #endif

+#if !_DEBUG && CONFIG_IS_ENABLED(LOG)

+#define debug_cond(cond, fmt, args...) \

• do { \

• if (1)				\
  

• 	log(LOG_CATEGORY, LOGL_DEBUG, fmt, ##args); \
  

• } while (0)

+#else /* _DEBUG */

/*

• Output a debug text when condition "cond" is met. The "cond"

should be

• computed by a preprocessor in the best case, allowing for the best

@@ -33,6 +124,8 @@ printf(pr_fmt(fmt), ##args); \ } while (0)

+#endif /* _DEBUG */

/* Show a message if DEBUG is defined in a file */ #define debug(fmt, args...) \ debug_cond(_DEBUG, fmt, ##args) @@ -56,4 +149,146 @@ void __assert_fail(const char *assertion, const char *file, unsigned int line, ({ if (!(x) && _DEBUG) \ __assert_fail(#x, __FILE__, __LINE__, __func__); })

+/**

• • struct log_rec - a single log record
• • Holds information about a single record in the log
• • Members marked as 'not allocated' are stored as pointers and the

caller is

• • responsible for making sure that the data pointed to is not

overwritten.

• • Memebers marked as 'allocated' are allocated (e.g. via strdup())

by the log

• • system.
• • @cat: Category, representing a uclass or part of U-Boot
• • @level: Severity level, less severe is higher
• • @file: Name of file where the log record was generated (not

allocated)

• • @line: Line number where the log record was generated
• • @func: Function where the log record was generated (not allocated)
• • @msg: Log message (allocated)
• */

+struct log_rec {

• enum log_category_t cat;
• enum log_level_t level;
• const char *file;
• int line;
• const char *func;
• const char *msg;

+};

+struct log_device;

+/**

• • struct log_driver - a driver which accepts and processes log

records

• • @name: Name of driver
• */

+struct log_driver {

• const char *name;
• /**

• * emit() - emit a log record
  

• *
  

• * Called by the log system to pass a log record to a
  

particular driver

• * for processing. The filter is checked before calling this
  

function.

• */
  

• int (*emit)(struct log_device *ldev, struct log_rec *rec);

+};

+/**

• • struct log_device - an instance of a log driver
• • Since drivers are set up at build-time we need to have a separate

device for

• • the run-time aspects of drivers (currently just a list of filters

to apply

• • to records send to this device).
• • @next_filter_num: Seqence number of next filter filter added

(0=no filters

• • yet). This increments with each new filter on the device,

but never

• • decrements
• • @drv: Pointer to driver for this device
• • @filter_head: List of filters for this device
• • @sibling_node: Next device in the list of all devices
• */

+struct log_device {

• int next_filter_num;
• struct log_driver *drv;
• struct list_head filter_head;
• struct list_head sibling_node;

+};

+enum {

• LOGF_MAX_CATEGORIES = 5, /* maximum categories per

filter */ +};

+enum log_filter_flags {

• LOGFF_HAS_CAT = 1 << 0, /* Filter has

a category list */ +};

+/**

• • struct log_filter - criterial to filter out log messages
• • @filter_num: Sequence number of this filter. This is returned

when adding a

• • new filter, and must be provided when removing a

previously added

• • filter.
• • @flags: Flags for this filter (LOGFF_...)
• • @cat_list: List of categories to allow (terminated by LOGC_none).

If empty

• • then all categories are permitted. Up to

LOGF_MAX_CATEGORIES entries

• • can be provided
• • @max_level: Maximum log level to allow
• • @file_list: List of files to allow, separated by comma. If NULL

then all

• • files are permitted
• • @sibling_node: Next filter in the list of filters for this log

device

• */

+struct log_filter {

• int filter_num;
• int flags;
• enum log_category_t cat_list[LOGF_MAX_CATEGORIES];
• enum log_level_t max_level;
• const char *file_list;
• struct list_head sibling_node;

+};

+#define LOG_DRIVER(_name) \

• ll_entry_declare(struct log_driver, _name, log_driver)

+/**

• • log_add_filter() - Add a new filter to a log device
• • @drv_name: Driver name to add the filter to (since each driver

only has a

• • single device)
• • @cat_list: List of categories to allow (terminated by LOGC_none).

If empty

• • then all categories are permitted. Up to

LOGF_MAX_CATEGORIES entries

• • can be provided
• • @max_level: Maximum log level to allow
• • @file_list: List of files to allow, separated by comma. If NULL

then all

• • files are permitted
• • @return the sequence number of the new filter (>=0) if the filter

was added,

• • or a -ve value on error
• */

+int log_add_filter(const char *drv_name, enum log_category_t cat_list[],

•    enum log_level_t max_level, const char
  

*file_list); + +/**

• • log_remove_filter() - Remove a filter from a log device
• • @drv_name: Driver name to remove the filter from (since each

driver only has

• • a single device)
• • @filter_num: Filter number to remove (as returned by

log_add_filter())

• • @return 0 if the filter was removed, -ENOENT if either the driver

or the

• • filter number was not found
• */

+int log_remove_filter(const char *drv_name, int filter_num);

+#if CONFIG_IS_ENABLED(LOG) +/**

• • log_init() - Set up the log system ready for use
• • @return 0 if OK, -ENOMEM if out of memory
• */

+int log_init(void); +#else +static inline int log_init(void) +{

• return 0;

+} +#endif

#endif

Best regards,

Lukasz Majewski

--

DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de