On Wed, Jan 28, 2015 at 10:07:51PM +0100, Pavel Machek wrote: > On Fri 2015-01-23 12:37:11, Tom Zanussi wrote: > > Some embedded systems with tightly controlled userspace have no use > > for /dev/zero, and could benefit from the size savings gained by > > omitting it. Add a new EMBEDDED config option to disable it. > > > > bloat-o-meter (based on tinyconfig): > > > > add/remove: 0/3 grow/shrink: 0/1 up/down: 0/-391 (-391) > > function old new delta > > chr_dev_init 162 147 -15 > > mmap_zero 16 - -16 > > zero_fops 116 - -116 > > zero_bdi 244 - -244 > > > > Signed-off-by: Tom Zanussi <tom.zanu...@linux.intel.com> > > I'm not sure that 400 bytes are worth additional Kconfig noise. .. and > pretty much everyone needs /dev/zero...
Relatively few, actually, given MMAP_ANONYMOUS. Memory isn't allocated via an mmap of /dev/zero. It's useful for systems with shells that want to redirect from it or read from it, but less useful for environments with entirely compiled code. /dev/null is much more commonly needed, though there are still systems that won't need it (and can just disable read/writes on an fd entirely rather than duping /dev/null to that fd). That said, I'd be entirely in favor of consolidating many of these "miscellaneous character device" options into a couple of Kconfig options. It doesn't seem critical to *individually* control each of these files in /dev. Personally, I'm hoping that we eventually end up with a disableable CONFIG_CHAR similar to CONFIG_BLOCK. - Josh Triplett -- 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/
