I'm investigating a performance degradation in yaffs when xattribs are enabled. Yes, I know yaffs is not part of mainline Linux yet, but this is really a vfs question. What I notice is that on every write the "security.capability" xattribute gets checked. Surely once the vfs has tried reading this once it should not try again on every write. Herewith a call stack [ 2317.288740] [<f85b3b17>] yaffs_getxattr+0x27/0xa0 [yaffs2] [ 2317.288746] [<f85b3af0>] ? yaffs_getxattr+0x0/0xa0 [yaffs2] [ 2317.288750] [<c03091c7>] cap_inode_need_killpriv+0x37/0x50 [ 2317.288753] [<c030a434>] security_inode_need_killpriv+0x14/0x20 [ 2317.288757] [<c01dda2d>] file_remove_suid+0x1d/0x60 [ 2317.288761] [<c01dfd8a>] __generic_file_aio_write+0x25a/0x550 [ 2317.288764] [<c0229eef>] ? link_path_walk+0x42f/0x9b0 [ 2317.288768] [<c023075f>] ? dput+0x6f/0xd0 [ 2317.288772] [<c01e00d8>] generic_file_aio_write+0x58/0xc0 [ 2317.288775] [<c021e819>] do_sync_write+0xb9/0xf0 [ 2317.288779] [<c0222954>] ? cp_new_stat64+0xe4/0x100 [ 2317.288783] [<c0338346>] ? apparmor_file_permission+0x16/0x20 [ 2317.288786] [<c030ba4d>] ? security_file_permission+0x1d/0x80 [ 2317.288790] [<c021e9b1>] ? rw_verify_area+0x71/0xe0 [ 2317.288793] [<c021eabb>] vfs_write+0x9b/0x160 [ 2317.288796] [<c021e760>] ? do_sync_write+0x0/0xf0 [ 2317.288800] [<c021f4a2>] sys_write+0x42/0x70 [ 2317.288803] [<c0102cdf>] sysenter_do_call+0x12/0x28 [ 2317.288806] yaffs_getxattr "security.capability" from object 257 Any hints as to why this is happening and how to stop this from happening? Thanks -- Charles -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
