Re: rump_sys_rename & tmpfs ... memory leak ?

[Antti Kantee <pooka%cs.hut.fi@localhost>]

On Tue Apr 28 2009 at 13:56:03 +0200, Nicolas Joly wrote:
> 
> Hi,
> 
> While learning how to use rump, i encountered a possible memory leak
> with rump_sys_rename(), when run on a tmpfs mount.
> 
> The attached sample, seems to leaks some memory (about 4MB/sec on my
> amd64) ... And the problem goes away if i remove/comment the
> rump_sys_rename() call. I tried some other fs, but failed to reproduce
> the problem.

Right, I ran into this while debugging the tmpfs rename race you reported,
but was busy back then and managed to forget all about it later.
Thanks for reminding me.  I fixed it in rev 1.55 of rumpkern/vm.c.

==22185== 880 bytes in 220 blocks are definitely lost in loss record 5 of 7
==22185==    at 0x61285EA: calloc (vg_replace_malloc.c:279)
==22185==    by 0x66FEF55: rumpuser_mutex_init (in /usr/lib/librumpuser.so.0)
==22185==    by 0x6454040: rumpns_mutex_init (locks.c:90)
==22185==    by 0x645346E: rumpns_uao_create (vm.c:231)
==22185==    by 0x6167C5E: rumpns_tmpfs_alloc_node (tmpfs_subr.c:173)
==22185==    by 0x61685FE: rumpns_tmpfs_alloc_file (tmpfs_subr.c:475)
==22185==    by 0x616473C: rumpns_tmpfs_create (tmpfs_vnops.c:266)
==22185==    by 0x642E4DB: rumpns_VOP_CREATE (vnode_if.c:178)
==22185==    by 0x6205C6E: rumpns_vn_open (vfs_vnops.c:178)
==22185==    by 0x62098C5: rumpns_sys_open (vfs_syscalls.c:1327)

mmm, valgrind