On Sat, Oct 11, 2014 at 08:32:49AM -0700, Joe Perches wrote:
On Sat, 2014-10-11 at 17:03 +0530, Sudip Mukherjee wrote:
On Sat, Oct 11, 2014 at 03:48:11AM -0700, Joe Perches wrote:
On Sat, 2014-10-11 at 14:39 +0530, Sudip Mukherjee wrote:
On Sat, Oct 11, 2014 at 03:20:56PM +0800, Raymond Yau wrote:
<snip> > > > > --- > > > > > > > > > > > static int vortex_core_init(vortex_t *vortex) > > > > { > > > > > > > > - pr_info( "Vortex: init.... "); > > > > + dev_info(vortex->card->dev, "init.... "); > > > > > > Is it possible to add linefeed since "done/n" won't appear in the same > > > line with init nor shutdown? > > > > > should we add linefeed ? > > as of now it will print init.... then it will print done as the init is complete. > > so dmesg will show us: > > > > init....done. > > > > same for shutdown. > > but if we give linefeed , then it will become : > > > > init.... > > done. > > > > the meaning will be lost. and many user might just wonder what is done ? > [] > > > > @@ -2738,7 +2744,7 @@ static int vortex_core_init(vortex_t *vortex) > > > > static int vortex_core_shutdown(vortex_t * vortex) > > > > { > > > > > > > > - pr_info( "Vortex: shutdown..."); > > > > + dev_info(vortex->card->dev, "shutdown..."); > > > > #ifndef CHIP_AU8820 > > > > vortex_eq_free(vortex); > > > > vortex_Vort3D_disable(vortex); > > > > @@ -2760,7 +2766,7 @@ static int vortex_core_shutdown(vortex_t * vortex) > > > > msleep(5); > > > > hwwrite(vortex->mmio, VORTEX_IRQ_SOURCE, 0xffff); > > > > > > > > - pr_info( "done.\n"); > > > > + dev_info(vortex->card->dev, "done.\n"); > > > > return 0; > > > > } > > It's actually on 2 lines before your patch. > > pr_info("a"); > pr_info("b\n"); > > already emits 2 separate lines. > > pr_info("a"); > pr_cont("b\n"); > > emits a single line "ab" > (unless some other thread emits something in-between) > > pr_cont or a bare printk can be used after a dev_info > without a newline to avoid unwanted newlines.
i think i was not thinking while writing the previous mail.
It seems you were thinking then and now, but unfortunately, you are assuming a bit more than you have actual experience or knowledge of printk inner workings.
pr_info("a"); pr_info("b\n"); should print as "ab" ,
This is not true.
All pr_<level> uses but pr_cont always start on a new line by emitting a newline if the last line did not have one.
oops... i have never tried with pr_* without a \n. I was thinking it will work like printf. sorry for the noise i created. and thanks for the information about those 2 commits. so, now in this case what will you suggest - shutdown and done both terminated by \n or some thing like : "shutdown process started" and then "shutdown done"....
thanks sudip
The difference between using:
pr_info("a") pr_info("b\n")
and
pr_info("a\n") pr_info("b\n")
is not emitted line count.
The first may unintentionally be continued by another thread using a printk that does not start with a KERN_<LEVEL>.
printk has had this behavior for ~5 years since these 2 commits:
commit e28d713704117bca0820c732210df6075b09f13b Author: Linus Torvalds torvalds@linux-foundation.org Date: Tue Jun 16 11:02:28 2009 -0700
printk: Add KERN_DEFAULT printk log-level This adds a KERN_DEFAULT loglevel marker, for when you cannot decide which loglevel you want, and just want to keep an existing printk with the default loglevel. The difference between having KERN_DEFAULT and having no log-level marker at all is two-fold: - having the log-level marker will now force a new-line if the previous printout had not added one (perhaps because it forgot, but perhaps because it expected a continuation) - having a log-level marker is required if you are printing out a message that otherwise itself could perhaps otherwise be mistaken for a log-level.and
commit 5fd29d6ccbc98884569d6f3105aeca70858b3e0f Author: Linus Torvalds torvalds@linux-foundation.org Date: Tue Jun 16 10:57:02 2009 -0700
printk: clean up handling of log-levels and newlines It used to be that we would only look at the log-level in a printk() after explicit newlines, which can cause annoying problems when the previous printk() did not end with a '\n'. In that case, the log-level marker would be just printed out in the middle of the line, and be seen as just noise rather than change the logging level. This changes things to always look at the log-level in the first bytes of the printout. If a log level marker is found, it is always used as the log-level. Additionally, if no newline existed, one is added (unless the log-level is the explicit KERN_CONT marker, to explicitly show that it's a continuation of a previous line).