On Thu, 2007-06-07 at 12:43 -0400, Albert Cahalan wrote: > On 6/7/07, Badari Pulavarty <[EMAIL PROTECTED]> wrote: > > > BTW, I agree with Eric that its would be nice to use shmid as part > > of name instead of forcing to be as inode number. It should be > > possible for pmap to workout shmid from "key" or name. Isn't it ? > > It is not at all nice. > > 1. it's incompatible ABI breakage > 2. where will you put the key then, in the inode? :-)
Nope. Currently "key" is part of the name (but its not unique). > > Changing to "SYSVID%d" is no good either. Look, people > are ***parsing*** this stuff in /proc. The /proc filesystem > is not some random sandbox to be playing in. > > Before you go messing with it, note that the device number > also matters. (it's per-boot dynamic, but that's OK) > That's how one knows that /SYSV00000000 is not just > a regular file; sadly these didn't get a non-/ prefix. > (and no you can't fix that now; it's way too late) > > Next time you feel like breaking an ABI, mind putting > "LET'S BREAK AN ABI!" in the subject of your email? I am not breaking ABI. Its already broken in the current mainline. I am trying to fix it by putting back the ino# as shmid. Eric had a suggestion that, instead of depending on the inode# to be shmid, we could embed shmid into name (instead of "key" which is currently not unique). > BTW, I suspect this kind of thing also breaks: > a. fuser, lsof, and other resource usage display tools > b. various obscure emulators (similar to valgrind) If you strongly feel that "old" behaviour needs to be retained, here is the patch I originally suggested. Thanks, Badari "ino#" in /proc/pid/maps used to match "ipcs -m" output for shared memory (shmid). It was useful in debugging, but its changed recently. This patch sets inode number to shared memory id to match /proc/pid/maps. Signed-off-by: Badari Pulavarty <[EMAIL PROTECTED]> Index: linux-2.6.22-rc4/ipc/shm.c =================================================================== --- linux-2.6.22-rc4.orig/ipc/shm.c 2007-06-04 17:57:25.000000000 -0700 +++ linux-2.6.22-rc4/ipc/shm.c 2007-06-06 08:23:57.000000000 -0700 @@ -397,6 +397,7 @@ static int newseg (struct ipc_namespace shp->shm_nattch = 0; shp->id = shm_buildid(ns, id, shp->shm_perm.seq); shp->shm_file = file; + file->f_dentry->d_inode->i_ino = shp->id; ns->shm_tot += numpages; shm_unlock(shp); - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/