[PATCH v3 00/17] generic hashtable implementation

Sasha Levin
2012-08-22T02:26:53Z

There are quite a few places in the kernel which implement a hashtable
in a very similar way. Instead of having implementations of a hashtable
all over the kernel, we can re-use the code.

Since it looks like all the major issues we're addressed in the RFC phase
and no major issues were raised with this patch set, I'd be happy to see
this getting merged so that work could continue on different aspects of
the hashtable. Some interesting directions include:

- Introducing a dynamic RCU hashtable such as the one Mathieu Desnoyers
wrote about out in the userspace RCU.

- Replacing the rest of the the kernel structures which use the same basec
hashtable construct to use this new interface.

- Same as above, but for non-obvious places (for example, I'm looking into
using the hashtable to store KVM vcpus instead of the linked list being used
there now - this should help performance with a large amount of vcpus).

Changes since v2:
- Documentation improvements from Mathieu Desnoyers.
- Converted the SUNRPC audit code to use hashtables as well. Since that code
requires a dynamic hashtable this shows off the _size() API usage.

Changes since v1:

- Added missing hash_init in rds and lockd.
- Addressed the userns comments by Eric Biederman.
- Ran a small test to confirm hash_32 does a good job for low key
values (1-10000), which showed it did - this resulted in no changes to the
code.

Sasha Levin (17):
hashtable: introduce a small and naive hashtable
userns: use new hashtable implementation
mm,ksm: use new hashtable implementation
workqueue: use new hashtable implementation
mm/huge_memory: use new hashtable implementation
tracepoint: use new hashtable implementation
net,9p: use new hashtable implementation
block,elevator: use new hashtable implementation
SUNRPC/cache: use new hashtable implementation
dlm: use new hashtable implementation
net,l2tp: use new hashtable implementation
dm: use new hashtable implementation
lockd: use new hashtable implementation
net,rds: use new hashtable implementation
openvswitch: use new hashtable implementation
tracing output: use new hashtable implementation
SUNRPC: use new hashtable implementation in auth

block/blk.h | 2 +-
block/elevator.c | 23 +--
drivers/md/dm-snap.c | 24 +--
drivers/md/persistent-data/dm-block-manager.c | 1 -
.../persistent-data/dm-persistent-data-internal.h | 19 --
.../md/persistent-data/dm-transaction-manager.c | 30 +--
fs/dlm/lowcomms.c | 47 +---
fs/lockd/svcsubs.c | 66 +++--
include/linux/elevator.h | 5 +-
include/linux/hashtable.h | 291 ++++++++++++++++++++
kernel/trace/trace_output.c | 20 +-
kernel/tracepoint.c | 27 +-
kernel/user.c | 33 +--
kernel/workqueue.c | 86 +-----
mm/huge_memory.c | 57 +---
mm/ksm.c | 33 +--
net/9p/error.c | 21 +-
net/l2tp/l2tp_core.c | 134 ++++------
net/l2tp/l2tp_core.h | 8 +-
net/l2tp/l2tp_debugfs.c | 19 +-
net/openvswitch/vport.c | 30 +--
net/rds/bind.c | 28 ++-
net/rds/connection.c | 102 +++----
net/sunrpc/auth.c | 45 ++--
net/sunrpc/cache.c | 20 +-
25 files changed, 617 insertions(+), 554 deletions(-)
delete mode 100644 drivers/md/persistent-data/dm-persistent-data-internal.h
create mode 100644 include/linux/hashtable.h

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1.7.8.6