mbox series

[RFC,v3,0/1] fs/namespace: defer RCU sync for MNT_DETACH umount

Message ID 20240626201129.272750-2-lkarpins@redhat.com (mailing list archive)
Headers show
Series fs/namespace: defer RCU sync for MNT_DETACH umount | expand

Message

Lucas Karpinski June 26, 2024, 8:07 p.m. UTC 
Hi all,                                            
                                                   
Attached is v3 of the umount optimization. Please take a look at v1 for
the original introduction to the problem. Al made it clear in the
RFC v1 that if a filesystem is shut down by umount(2), that the
shut down needs to be completed before the return from the syscall. In 
the RFC v2, it was pointed out that call_rcu can block within an 
interrupt context. This RFC v3 addresses both that and removes 
unneccesary code by taking advantage of mntput for the cleanup of lazy 
umounts.                                           
                                                   
Lucas                                              
                                                   
v3:                                                
- Removed unneeded code for lazy umount case.      
- Don't block within interrupt context.            
v2:                                                
- Only defer releasing umount'ed filesystems for lazy umounts
v1:                                                
https://lore.kernel.org/all/20230119205521.497401-1-echanude@redhat.com/

Lucas Karpinski (1):
  fs/namespace: remove RCU sync for MNT_DETACH umount

 fs/namespace.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)