log: allow for message continuation
Some drivers use macro pr_cont() for continuing a message sent via printk.
Hence if we want to convert printk messaging to using the logging system,
we must support continuation of log messages too.
As pr_cont() does not provide a message level we need a means of
remembering the last log level.
With the patch a pseudo log level LOGL_CONT as well as a pseudo log
category LOGC_CONT are introduced. Using these results in the application
of the same log level and category as in the previous log message.
Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/common/log.c b/common/log.c
index 6a59f2e..d830883 100644
--- a/common/log.c
+++ b/common/log.c
@@ -191,10 +191,12 @@
* 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
+ * filters which block the record.
*
- * @rec: Log record to dispatch
- * @return 0 (meaning success)
+ * All log messages created while processing log record @rec are ignored.
+ *
+ * @rec: log record to dispatch
+ * Return: 0 msg sent, 1 msg not sent while already dispatching another msg
*/
static int log_dispatch(struct log_rec *rec)
{
@@ -206,7 +208,7 @@
* as this might result in infinite recursion.
*/
if (gd->processing_msg)
- return 0;
+ return 1;
/* Emit message */
gd->processing_msg = true;
@@ -226,6 +228,12 @@
struct log_rec rec;
va_list args;
+ /* Check for message continuation */
+ if (cat == LOGC_CONT)
+ cat = gd->logc_prev;
+ if (level == LOGL_CONT)
+ level = gd->logl_prev;
+
rec.cat = cat;
rec.level = level & LOGL_LEVEL_MASK;
rec.force_debug = level & LOGL_FORCE_DEBUG;
@@ -241,7 +249,10 @@
gd->log_drop_count++;
return -ENOSYS;
}
- log_dispatch(&rec);
+ if (!log_dispatch(&rec)) {
+ gd->logc_prev = cat;
+ gd->logl_prev = level;
+ }
return 0;
}
@@ -381,6 +392,8 @@
if (!gd->default_log_level)
gd->default_log_level = CONFIG_LOG_DEFAULT_LEVEL;
gd->log_fmt = log_get_default_format();
+ gd->logc_prev = LOGC_NONE;
+ gd->logl_prev = LOGL_INFO;
return 0;
}
diff --git a/doc/develop/logging.rst b/doc/develop/logging.rst
index 28340a4..528280c 100644
--- a/doc/develop/logging.rst
+++ b/doc/develop/logging.rst
@@ -38,6 +38,9 @@
* LOGL_DEBUG_CONTENT - Debug message showing full message content
* LOGL_DEBUG_IO - Debug message showing hardware I/O access
+To continue a log message in a separate call of function log() use
+
+* LOGL_CONT - Use same log level as in previous call
Logging category
----------------
@@ -56,6 +59,9 @@
* LOGC_DT - Related to device tree control
* LOGC_EFI - Related to EFI implementation
+To continue a log message in a separate call of function log() use
+
+* LOGC_CONT - Use same category as in previous call
Enabling logging
----------------
diff --git a/include/asm-generic/global_data.h b/include/asm-generic/global_data.h
index db83f59..0157af1 100644
--- a/include/asm-generic/global_data.h
+++ b/include/asm-generic/global_data.h
@@ -371,6 +371,18 @@
* while another message is being processed.
*/
bool processing_msg;
+ /**
+ * @logc_prev: logging category of previous message
+ *
+ * This value is used as logging category for continuation messages.
+ */
+ int logc_prev;
+ /**
+ * @logl_pref: logging level of the previous message
+ *
+ * This value is used as logging level for continuation messages.
+ */
+ int logl_prev;
#endif
#if CONFIG_IS_ENABLED(BLOBLIST)
/**
diff --git a/include/log.h b/include/log.h
index 6de5e61..58787a3 100644
--- a/include/log.h
+++ b/include/log.h
@@ -38,6 +38,7 @@
LOGL_FIRST = LOGL_EMERG,
LOGL_MAX = LOGL_DEBUG_IO,
+ LOGL_CONT = -1, /* Use same log level as in previous call */
};
/**
@@ -65,6 +66,7 @@
LOGC_COUNT, /* Number of log categories */
LOGC_END, /* Sentinel value for a list of log categories */
+ LOGC_CONT = -1, /* Use same category as in previous call */
};
/* Helper to cast a uclass ID to a log category */