[patch 0/3] mm: memcontrol: lockless page counters v3

Johannes Weiner
2014-10-14T01:46:15Z

Hi,

this series replaces the spinlock_irq-protected 64-bit res_counters
with lockless word-sized page counters. This improves memory cgroup
scalability on the higher end and gets rid of 64-bit math on 32-bit
machines in the core accounting, but also generally simplifies the
counter code and interface.

Version 3 has a few more touch-ups based on reviews from Michal and
Vladimir:

- documented ordering between limit() and try_charge() [vladimir]
- removed charge revert during uncharge underflow [michal]
- reworked limit update code flow [michal]
- removed rounding-up in limit setting [michal]
- fixed mem_cgroup_margin() memsw calculation [michal]
- updated page_counter raciness comments [vladimir]

Version 2:

cleanups:
- moved new page_counter API to its own file [vladimir, michal]
- documented page counter API [vladimir]
- documented acceptable race conditions [vladimir]
- split out res_counter removal to reduce patch size [vladimir]
- split out hugetlb controller conversion to reduce patch size
- split page_counter_charge and page_counter_try_charge [vladimir]
- wrapped signed-to-unsigned read in page_counter_read() [vladimir]
- wrapped watermark reset in page_counter_reset_watermark() [vladimir]
- reverted counter->limited back to counter->failcnt [vladimir]
- changed underflow to WARN_ON_ONCE and counter revert [kame, vladimir]

fixes:
- fixed kmem's value for unlimited [vladimir]
- fixed page_counter_cancel() return value [vladimir]
- based page counter range on atomic_long_t's max [vladimir]
- fixed tcp memcontrol's usage reporting [vladimir]
- fixed hugepage limit page alignment [vladimir]
- fixed page_counter_limit() serialization [vladimir]

optimizations:
- converted page_counter_try_charge() from CAS to FAA [vladimir]

Documentation/cgroups/hugetlb.txt | 2 +-
Documentation/cgroups/memory.txt | 4 +-
Documentation/cgroups/resource_counter.txt | 197 ---------
include/linux/hugetlb_cgroup.h | 1 -
include/linux/memcontrol.h | 5 +-
include/linux/page_counter.h | 49 +++
include/linux/res_counter.h | 223 ----------
include/net/sock.h | 26 +-
init/Kconfig | 12 +-
kernel/Makefile | 1 -
kernel/res_counter.c | 211 ---------
mm/Makefile | 1 +
mm/hugetlb_cgroup.c | 103 +++--
mm/memcontrol.c | 633 +++++++++++++--------------
mm/page_counter.c | 203 +++++++++
net/ipv4/tcp_memcontrol.c | 87 ++--
16 files changed, 669 insertions(+), 1089 deletions(-)