On Thu, 9 Aug 2012, Ren, Qiaowei wrote: > On Wed, 8 Aug 2012, David Rientjes wrote: > > On Wed, 8 Aug 2012, Qiaowei Ren wrote: > > > > > Add a shmaps entry to /proc/pid: show information about shared memory in > > > an address space. > > > > > > People that use shared memory and want to perform an analyzing about it. > > > For example, judge whether any memory address is shared. This file just > > > contains 'share' part of /proc/pid/maps now. There are too many contents > > > in maps, and so we have to do a lot of analysis to obtain relative > > > information every time. > > > > > > Signed-off-by: Qiaowei Ren <qiaowei....@intel.com> > > > > Nack as unnecessary; /proc/pid/maps already explicitly emits 's' for > > VM_MAYSHARE and 'p' otherwise so this information is already available to > > userspace. > > > > Thanks for your reply. There are so many contents in /proc/pid/maps, and > usually only a very small minority of those are about shared memory in > address space of every process. So I hope that a new file maybe provide some > convenience. Could you tell me how to get such information except analyzing > 'maps' file?
You are joking? Please imagine what the kernel and /proc would look like if it provided a personally tailored /proc file to everybody who could not be bothered to parse the information already shown there. Sure, there is already lots of ugly and duplicative junk under /proc, which usually has to be kept to preserve back compatibility; but please do not try to add to it. There is sometimes an excuse if some fields of an existing /proc file are significantly more expensive for the kernel to compute than others: then a file which separates them can save processing. But that is definitely not the case here. A side issue would be whether parsing /proc/pid/maps for 's' VM_MAYSHARE mappings (or your equivalent patch) actually tells you what you want to know about "shared memory" - that would depend on what you really want to know, and what you mean by shared memory. Hugh -- 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/
