logging: Use vprintk for string formatting by default
Previously, _prf function was used when present and _vprintk
was used otherwise. _prf supports reacher formatting but at
cost of 3k flash and >250 bytes on stack. Stack usage then
depended on which function was used and that was causing
troubles when trimming stack sizes.
Signed-off-by: Krzysztof Chruscinski <krzysztof.chruscinski@nordicsemi.no>
diff --git a/subsys/logging/Kconfig b/subsys/logging/Kconfig
index 1e44f6c..32c7d1a 100644
--- a/subsys/logging/Kconfig
+++ b/subsys/logging/Kconfig
@@ -212,13 +212,14 @@
flawlessly in that mode because one log operation can be interrupted
by another one in the higher priority context.
-config LOG_DISABLE_FANCY_OUTPUT_FORMATTING
+config LOG_ENABLE_FANCY_OUTPUT_FORMATTING
depends on !NEWLIB_LIBC && !ARCH_POSIX
- bool "Use vprintk() instead of minimal libc _prf()"
+ bool "Format strings with minimal libc _prf() instead of _vprintk()"
help
- Selecting this option will choose vprintk for handling format
- strings instead of the more robust _prf() function in minimal
- libc. Choosing this option can save around ~3K flash.
+ Selecting this option will choose more robust _prf() function from
+ minimal libc for handling format strings instead of the _vprintk()
+ function. Choosing this option adds around ~3K flash and ~250 bytes on
+ stack.
if !LOG_IMMEDIATE
diff --git a/subsys/logging/log_output.c b/subsys/logging/log_output.c
index 52a7f6c..84677f0 100644
--- a/subsys/logging/log_output.c
+++ b/subsys/logging/log_output.c
@@ -115,7 +115,7 @@
va_start(args, fmt);
#if !defined(CONFIG_NEWLIB_LIBC) && !defined(CONFIG_ARCH_POSIX) && \
- !defined(CONFIG_LOG_DISABLE_FANCY_OUTPUT_FORMATTING)
+ defined(CONFIG_LOG_ENABLE_FANCY_OUTPUT_FORMATTING)
length = _prf(out_func, (void *)log_output, (char *)fmt, args);
#else
_vprintk(out_func, (void *)log_output, fmt, args);
@@ -553,7 +553,7 @@
}
#if !defined(CONFIG_NEWLIB_LIBC) && !defined(CONFIG_ARCH_POSIX) && \
- !defined(CONFIG_LOG_DISABLE_FANCY_OUTPUT_FORMATTING)
+ defined(CONFIG_LOG_ENABLE_FANCY_OUTPUT_FORMATTING)
length = _prf(out_func, (void *)log_output, (char *)fmt, ap);
#else
_vprintk(out_func, (void *)log_output, fmt, ap);
