On Wed 30-10-13 15:12:48, Andrew Morton wrote: > Subject: + mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch added to -mm tree > To: hannes@xxxxxxxxxxx,mhocko@xxxxxxx > From: akpm@xxxxxxxxxxxxxxxxxxxx > Date: Wed, 30 Oct 2013 15:12:48 -0700 > > > The patch titled > Subject: mm: memcg: lockdep annotation for memcg OOM lock > has been added to the -mm tree. Its filename is > mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > > This patch should soon appear at > http://ozlabs.org/~akpm/mmots/broken-out/mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > and later at > http://ozlabs.org/~akpm/mmotm/broken-out/mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > > Before you just go and hit "reply", please: > a) Consider who else should be cc'ed > b) Prefer to cc a suitable mailing list as well > c) Ideally: find the original patch on the mailing list and do a > reply-to-all to that, adding suitable additional cc's > > *** Remember to use Documentation/SubmitChecklist when testing your code *** > > The -mm tree is included into linux-next and is updated > there every 3-4 working days > > ------------------------------------------------------ > From: Johannes Weiner <hannes@xxxxxxxxxxx> > Subject: mm: memcg: lockdep annotation for memcg OOM lock > > The memcg OOM lock is a mutex-type lock that is open-coded due to memcg's > special needs. Add annotations for lockdep coverage. I am not sure what this gives us to be honest. AA and AB-BA deadlocks are impossible due to nature of the lock (it is trylock so we never block on it). > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> > Cc: Michal Hocko <mhocko@xxxxxxx> > Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > --- > > mm/memcontrol.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff -puN mm/memcontrol.c~mm-memcg-lockdep-annotation-for-memcg-oom-lock mm/memcontrol.c > --- a/mm/memcontrol.c~mm-memcg-lockdep-annotation-for-memcg-oom-lock > +++ a/mm/memcontrol.c > @@ -54,6 +54,7 @@ > #include <linux/page_cgroup.h> > #include <linux/cpu.h> > #include <linux/oom.h> > +#include <linux/lockdep.h> > #include "internal.h" > #include <net/sock.h> > #include <net/ip.h> > @@ -2046,6 +2047,12 @@ static int mem_cgroup_soft_reclaim(struc > return total; > } > > +#ifdef CONFIG_LOCKDEP > +static struct lockdep_map memcg_oom_lock_dep_map = { > + .name = "memcg_oom_lock", > +}; > +#endif > + > static DEFINE_SPINLOCK(memcg_oom_lock); > > /* > @@ -2083,7 +2090,8 @@ static bool mem_cgroup_oom_trylock(struc > } > iter->oom_lock = false; > } > - } > + } else > + mutex_acquire(&memcg_oom_lock_dep_map, 0, 1, _RET_IP_); > > spin_unlock(&memcg_oom_lock); > > @@ -2095,6 +2103,7 @@ static void mem_cgroup_oom_unlock(struct > struct mem_cgroup *iter; > > spin_lock(&memcg_oom_lock); > + mutex_release(&memcg_oom_lock_dep_map, 1, _RET_IP_); > for_each_mem_cgroup_tree(iter, memcg) > iter->oom_lock = false; > spin_unlock(&memcg_oom_lock); > _ > > Patches currently in -mm which might be from hannes@xxxxxxxxxxx are > > percpu-fix-this_cpu_sub-subtrahend-casting-for-unsigneds.patch > memcg-use-__this_cpu_sub-to-dec-stats-to-avoid-incorrect-subtrahend-casting.patch > mm-memcg-use-proper-memcg-in-limit-bypass.patch > mm-memcg-lockdep-annotation-for-memcg-oom-lock.patch > mm-memcg-fix-test-for-child-groups.patch > mm-nobootmemc-have-__free_pages_memory-free-in-larger-chunks.patch > memcg-refactor-mem_control_numa_stat_show.patch > memcg-support-hierarchical-memorynuma_stats.patch > memblock-factor-out-of-top-down-allocation.patch > memblock-introduce-bottom-up-allocation-mode.patch > x86-mm-factor-out-of-top-down-direct-mapping-setup.patch > x86-mem-hotplug-support-initialize-page-tables-in-bottom-up.patch > x86-acpi-crash-kdump-do-reserve_crashkernel-after-srat-is-parsed.patch > mem-hotplug-introduce-movable_node-boot-option.patch > swap-add-a-simple-detector-for-inappropriate-swapin-readahead-fix.patch > percpu-add-test-module-for-various-percpu-operations.patch > linux-next.patch > mm-avoid-increase-sizeofstruct-page-due-to-split-page-table-lock.patch > mm-rename-use_split_ptlocks-to-use_split_pte_ptlocks.patch > mm-convert-mm-nr_ptes-to-atomic_long_t.patch > mm-introduce-api-for-split-page-table-lock-for-pmd-level.patch > mm-thp-change-pmd_trans_huge_lock-to-return-taken-lock.patch > mm-thp-move-ptl-taking-inside-page_check_address_pmd.patch > mm-thp-do-not-access-mm-pmd_huge_pte-directly.patch > mm-hugetlb-convert-hugetlbfs-to-use-split-pmd-lock.patch > mm-convert-the-rest-to-new-page-table-lock-api.patch > mm-implement-split-page-table-lock-for-pmd-level.patch > x86-mm-enable-split-page-table-lock-for-pmd-level.patch > debugging-keep-track-of-page-owners-fix-2-fix-fix-fix.patch > -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>