On Sat, Jan 24, 2015 at 09:03:08AM -0500, Tejun Heo wrote: > There have been a couple different attempts at making this easier. > > 1. Way back, PeterZ tried printk '%pb' extension with the precision > for bit width - '%.*pb'. This was intuitive and made sense but > unfortunately triggered a compile warning about using precision > for a pointer. > > http://lkml.kernel.org/g/1336577562.2527.58.camel@twins
> So, this patch is another attempt at teaching printk and friends how > to print bitmaps. It's almost identical to what PeterZ tried with > precision but it uses the field width for the number of bits instead > of precision. The format used is '%*pb[l]', with the optional > trailing 'l' specifying list format instead of hex masks. > This is a valid format string and doesn't trigger compiler warnings; > however, it does make it impossible to specify output field width when > printing bitmaps. > I think this is an acceptable trade-off given how > much easier it makes printing bitmaps and that we don't have any > in-kernel user which is using the field width specification. Yeah, I suppose this is indeed the best we can do; and loosing the width thing (which is a rarely used feature for in kernel things) seems acceptable indeed. We did mention the option back then, but didn't pursue it. I like the extra 'l' fmt option. > Signed-off-by: Tejun Heo <t...@kernel.org> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org> -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
