tree 60643fb9d828c388d963ceb26504dce9890eabbb
parent 7de9c6ee3ecffd99e1628e81a5ea5468f7581a1f
author Eric Dumazet <eric.dumazet@gmail.com> 1287847081 -0400
committer Al Viro <viro@zeniv.linux.org.uk> 1288056371 -0400

fs: introduce a per-cpu last_ino allocator

new_inode() dirties a contended cache line to get increasing
inode numbers. This limits performance on workloads that cause
significant parallel inode allocation.

Solve this problem by using a per_cpu variable fed by the shared
last_ino in batches of 1024 allocations.  This reduces contention on
the shared last_ino, and give same spreading ino numbers than before
(i.e. same wraparound after 2^32 allocations).

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>