On Fri 28-08-15 18:01:58, Tejun Heo wrote: > task_struct->memcg_oom is a sub-struct containing fields which are > used for async memcg oom handling. Most task_struct fields aren't > packaged this way and it can lead to unnecessary alignment paddings. > This patch flattens it. > > * task.memcg_oom.memcg -> task.memcg_in_oom > * task.memcg_oom.gfp_mask -> task.memcg_oom_gfp_mask > * task.memcg_oom.order -> task.memcg_oom_order > * task.memcg_oom.may_oom -> task.memcg_may_oom > > In addition, task.memcg_may_oom is relocated to where other bitfields > are which reduces the size of task_struct. > > Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> > --- > Hello, > > These two patches are what survived from the following patchset. > > http://lkml.kernel.org/g/1440775530-18630-1-git-send-email-tj@xxxxxxxxxx > > Thanks. > > include/linux/memcontrol.h | 10 +++++----- > include/linux/sched.h | 13 ++++++------- > mm/memcontrol.c | 16 ++++++++-------- > 3 files changed, 19 insertions(+), 20 deletions(-) > > --- a/include/linux/memcontrol.h > +++ b/include/linux/memcontrol.h > @@ -407,19 +407,19 @@ void mem_cgroup_print_oom_info(struct me > > static inline void mem_cgroup_oom_enable(void) > { > - WARN_ON(current->memcg_oom.may_oom); > - current->memcg_oom.may_oom = 1; > + WARN_ON(current->memcg_may_oom); > + current->memcg_may_oom = 1; > } > > static inline void mem_cgroup_oom_disable(void) > { > - WARN_ON(!current->memcg_oom.may_oom); > - current->memcg_oom.may_oom = 0; > + WARN_ON(!current->memcg_may_oom); > + current->memcg_may_oom = 0; > } > > static inline bool task_in_memcg_oom(struct task_struct *p) > { > - return p->memcg_oom.memcg; > + return p->memcg_in_oom; > } > > bool mem_cgroup_oom_synchronize(bool wait); > --- a/include/linux/sched.h > +++ b/include/linux/sched.h > @@ -1451,7 +1451,9 @@ struct task_struct { > unsigned sched_reset_on_fork:1; > unsigned sched_contributes_to_load:1; > unsigned sched_migrated:1; > - > +#ifdef CONFIG_MEMCG > + unsigned memcg_may_oom:1; > +#endif > #ifdef CONFIG_MEMCG_KMEM > unsigned memcg_kmem_skip_account:1; > #endif > @@ -1782,12 +1784,9 @@ struct task_struct { > unsigned long trace_recursion; > #endif /* CONFIG_TRACING */ > #ifdef CONFIG_MEMCG > - struct memcg_oom_info { > - struct mem_cgroup *memcg; > - gfp_t gfp_mask; > - int order; > - unsigned int may_oom:1; > - } memcg_oom; > + struct mem_cgroup *memcg_in_oom; > + gfp_t memcg_oom_gfp_mask; > + int memcg_oom_order; > #endif > #ifdef CONFIG_UPROBES > struct uprobe_task *utask; > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -1652,7 +1652,7 @@ static void memcg_oom_recover(struct mem > > static void mem_cgroup_oom(struct mem_cgroup *memcg, gfp_t mask, int order) > { > - if (!current->memcg_oom.may_oom) > + if (!current->memcg_may_oom) > return; > /* > * We are in the middle of the charge context here, so we > @@ -1669,9 +1669,9 @@ static void mem_cgroup_oom(struct mem_cg > * and when we know whether the fault was overall successful. > */ > css_get(&memcg->css); > - current->memcg_oom.memcg = memcg; > - current->memcg_oom.gfp_mask = mask; > - current->memcg_oom.order = order; > + current->memcg_in_oom = memcg; > + current->memcg_oom_gfp_mask = mask; > + current->memcg_oom_order = order; > } > > /** > @@ -1693,7 +1693,7 @@ static void mem_cgroup_oom(struct mem_cg > */ > bool mem_cgroup_oom_synchronize(bool handle) > { > - struct mem_cgroup *memcg = current->memcg_oom.memcg; > + struct mem_cgroup *memcg = current->memcg_in_oom; > struct oom_wait_info owait; > bool locked; > > @@ -1721,8 +1721,8 @@ bool mem_cgroup_oom_synchronize(bool han > if (locked && !memcg->oom_kill_disable) { > mem_cgroup_unmark_under_oom(memcg); > finish_wait(&memcg_oom_waitq, &owait.wait); > - mem_cgroup_out_of_memory(memcg, current->memcg_oom.gfp_mask, > - current->memcg_oom.order); > + mem_cgroup_out_of_memory(memcg, current->memcg_oom_gfp_mask, > + current->memcg_oom_order); > } else { > schedule(); > mem_cgroup_unmark_under_oom(memcg); > @@ -1739,7 +1739,7 @@ bool mem_cgroup_oom_synchronize(bool han > memcg_oom_recover(memcg); > } > cleanup: > - current->memcg_oom.memcg = NULL; > + current->memcg_in_oom = NULL; > css_put(&memcg->css); > return true; > } > -- > To unsubscribe from this list: send the line "unsubscribe cgroups" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- 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>