lkml.org 
[lkml]   [2017]   [Oct]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v7 0/6] vfs: Use dlock list for SB's s_inodes list
On Thu, Oct 26, 2017 at 02:28:55PM -0400, Waiman Long wrote:
> On 10/05/2017 02:43 PM, Waiman Long wrote:
> >
> > This is a follow up of the following patchset:
> >
> > [PATCH v7 0/4] vfs: Use per-cpu list for SB's s_inodes list
> > https://lkml.org/lkml/2016/4/12/1009
> >
> > This patchset provides new APIs for a set of distributed locked lists
> > (one/CPU core) to minimize lock and cacheline contention. Insertion
> > and deletion to the list will be cheap and relatively contention free.
> > Lookup, on the other hand, may be a bit more costly as there are
> > multiple lists to iterate. This is not really a problem for the
> > replacement of superblock's inode list by dlock list included in
> > the patchset as lookup isn't needed.
> >
> > For use cases that need to do lookup, the dlock list can also be
> > treated as a set of hashed lists that scales with the number of CPU
> > cores in the system.
> >
> > Both patches 5 and 6 are added to support other use cases like epoll
> > nested callbacks, for example, which could use the dlock-list to
> > reduce lock contention problem.
> >
> > Patch 1 introduces the dlock list. The list heads are allocated
> > by kcalloc() instead of percpu_alloc(). Each list head entry is
> > cacheline aligned to minimize contention.
> >
> > Patch 2 replaces the use of list_for_each_entry_safe() in
> > evict_inodes() and invalidate_inodes() by list_for_each_entry().
> >
> > Patch 3 modifies the superblock and inode structures to use the dlock
> > list. The corresponding functions that reference those structures
> > are modified.
> >
> > Patch 4 makes the sibling CPUs use the same dlock list head to reduce
> > the number of list heads that need to be iterated.
> >
> > Patch 5 enables alternative use case of as a set of hashed lists.
> >
> > Patch 6 provides an irq safe mode specified at dlock-list allocation
> > time so that it can be within interrupt context.
> >
> > Jan Kara (1):
> > vfs: Remove unnecessary list_for_each_entry_safe() variants
> >
> > Waiman Long (5):
> > lib/dlock-list: Distributed and lock-protected lists
> > vfs: Use dlock list for superblock's inode list
> > lib/dlock-list: Make sibling CPUs share the same linked list
> > lib/dlock-list: Enable faster lookup with hashing
> > lib/dlock-list: Add an IRQ-safe mode to be used in interrupt handler
> >
> > fs/block_dev.c | 9 +-
> > fs/drop_caches.c | 9 +-
> > fs/inode.c | 38 +++---
> > fs/notify/fsnotify.c | 9 +-
> > fs/quota/dquot.c | 14 +-
> > fs/super.c | 7 +-
> > include/linux/dlock-list.h | 245 ++++++++++++++++++++++++++++++++++
> > include/linux/fs.h | 8 +-
> > lib/Makefile | 2 +-
> > lib/dlock-list.c | 322 +++++++++++++++++++++++++++++++++++++++++++++
> > 10 files changed, 609 insertions(+), 54 deletions(-)
> > create mode 100644 include/linux/dlock-list.h
> > create mode 100644 lib/dlock-list.c
> >
> Is there other objections about merging this patch series? With the
> additional patches 8 & 9 that I sent out on Oct 17, I think I had
> addressed all the concerns that I received so far. Please let me know
> what else do I need to do to make these patches mergeable?
>

Hi Waiman,

Have you read my email about the dlist_for_each_entry_safe():

https://marc.info/?l=linux-kernel&m=150831690725964&w=2

?

Regards,
Boqun

> Thanks,
> Longman
>
>
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2017-10-27 02:57    [W:0.149 / U:5.804 seconds]
©2003-2017 Jasper Spaans. hosted at Digital OceanAdvertise on this site