On Mon 2017-09-18 13:51:00, Prarit Bhargava wrote: > printk.time=1/CONFIG_PRINTK_TIME=1 adds a unmodified local hardware clock > timestamp to printk messages. The local hardware clock loses time each > day making it difficult to determine exactly when an issue has occurred in > the kernel log, and making it difficult to determine how kernel and > hardware issues relate to each other in real time. > > Make printk output different timestamps by adding options for no > timestamp, the local hardware clock, the monotonic clock, the boottime > clock, and the real clock. Allow a user to pick one of the clocks by > using the printk.time kernel parameter. Output the type of clock in > /sys/module/printk/parameters/time so userspace programs can interpret the > timestamp. > > diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c > index 512f7c2baedd..5e0bf2ef02f7 100644 > --- a/kernel/printk/printk.c > +++ b/kernel/printk/printk.c > @@ -1201,14 +1204,130 @@ static inline void boot_delay_msec(int level) > +static int printk_time = CONFIG_PRINTK_TIME_TYPE; > + > +static int printk_set_ts_source(enum timestamp_sources ts_source) > +{ > + int err = 0; > @@ -1861,6 +1980,7 @@ static size_t msg_print_text(const struct printk_log *msg, > bool syslog, char *buf, size_t size) { return 0; } > static bool suppress_message_printing(int level) { return false; } > > +static int printk_time; I worried if the variable should have got initialized. But it seems to be a relic from an older version. The variable is not longer used and needed when CONFIG_PRINTK is not defined. It is proved by gcc: CC kernel/printk/printk.o kernel/printk/printk.c:1983:12: warning: ‘printk_time’ defined but not used [-Wunused-variable] static int printk_time; > #endif /* CONFIG_PRINTK */ > > #ifdef CONFIG_EARLY_PRINTK Otherwise that patch looks fine. With the unused variable removed, feel free to use: Reviewed-by: Petr Mladek <pmladek@xxxxxxxx> Best Regards, Petr -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html