21 May
2019
21 May
'19
7:59 p.m.
On Tue, May 21, 2019 at 08:20:09PM +0100, Al Viro wrote:
On Tue, May 21, 2019 at 05:30:27PM +0100, David Howells wrote:
If we can live with close_from(int first) rather than close_range(), then this can perhaps be done a lot more efficiently by:
new = alloc_fdtable(first); spin_lock(&files->file_lock); old = files_fdtable(files); copy_fds(new, old, 0, first - 1); rcu_assign_pointer(files->fdt, new); spin_unlock(&files->file_lock); clear_fds(old, 0, first - 1); close_fdt_from(old, first); kfree_rcu(old);
I really hate to think how that would interact with POSIX locks...
POSIX locks store current->files in fl_owner; David's resizing the underlying files->fdt, just like growing from 64 to 256 fds.