diff options
author | Johannes Weiner <hannes@cmpxchg.org> | 2013-08-08 12:56:32 +1000 |
---|---|---|
committer | Dan Willemsen <dwillemsen@nvidia.com> | 2013-09-14 13:44:02 -0700 |
commit | c5ffca3f2332a408e9d216925d5d732ed67abcc7 (patch) | |
tree | ad7a1d7049ea416bae349349b3f88be8278d033c /mm | |
parent | af141cc49eb867c7f885052b29006de44c6d19e9 (diff) |
UPSTREAM mm: memcg: enable memcg OOM killer only for user faults
System calls and kernel faults (uaccess, gup) can handle an out of memory
situation gracefully and just return -ENOMEM.
Enable the memcg OOM killer only for user faults, where it's really the
only option available.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: azurIt <azurit@pobox.sk>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
(cherry picked from commit 31d1d8b2aa8733b4fe221b4bcbaa15aec3582b99)
Change-Id: If84752f6c46e464bc0d1d868ac543497425ba7cc
Reviewed-on: http://git-master/r/266405
GVS: Gerrit_Virtual_Submit
Reviewed-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Tested-by: Prashant Gaikwad <pgaikwad@nvidia.com>
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/filemap.c | 11 | ||||
-rw-r--r-- | mm/memcontrol.c | 2 | ||||
-rw-r--r-- | mm/memory.c | 40 |
3 files changed, 41 insertions, 12 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index 7905fe721aa8..c466f4c449e9 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1614,6 +1614,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) struct inode *inode = mapping->host; pgoff_t offset = vmf->pgoff; struct page *page; + bool memcg_oom; pgoff_t size; int ret = 0; @@ -1622,7 +1623,11 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) return VM_FAULT_SIGBUS; /* - * Do we have something in the page cache already? + * Do we have something in the page cache already? Either + * way, try readahead, but disable the memcg OOM killer for it + * as readahead is optional and no errors are propagated up + * the fault stack. The OOM killer is enabled while trying to + * instantiate the faulting page individually below. */ page = find_get_page(mapping, offset); if (likely(page) && !(vmf->flags & FAULT_FLAG_TRIED)) { @@ -1630,10 +1635,14 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf) * We found the page, so try async readahead before * waiting for the lock. */ + memcg_oom = mem_cgroup_toggle_oom(false); do_async_mmap_readahead(vma, ra, file, page, offset); + mem_cgroup_toggle_oom(memcg_oom); } else if (!page) { /* No page in the page cache at all */ + memcg_oom = mem_cgroup_toggle_oom(false); do_sync_mmap_readahead(vma, ra, file, offset); + mem_cgroup_toggle_oom(memcg_oom); count_vm_event(PGMAJFAULT); mem_cgroup_count_vm_event(vma->vm_mm, PGMAJFAULT); ret = VM_FAULT_MAJOR; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 82a187aea4c0..4e3441e37d32 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2613,7 +2613,7 @@ static int mem_cgroup_do_charge(struct mem_cgroup *memcg, gfp_t gfp_mask, return CHARGE_RETRY; /* If we don't need to call oom-killer at el, return immediately */ - if (!oom_check) + if (!oom_check || !current->memcg_oom.may_oom) return CHARGE_NOMEM; /* check OOM */ if (!mem_cgroup_handle_oom(mem_over_limit, gfp_mask, get_order(csize))) diff --git a/mm/memory.c b/mm/memory.c index 5a35443c01ad..5f2360272113 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3760,22 +3760,14 @@ unlock: /* * By the time we get here, we already hold the mm semaphore */ -int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, unsigned int flags) +static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, unsigned int flags) { pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t *pte; - __set_current_state(TASK_RUNNING); - - count_vm_event(PGFAULT); - mem_cgroup_count_vm_event(mm, PGFAULT); - - /* do counter updates before entering really critical section. */ - check_sync_rss_stat(current); - if (unlikely(is_vm_hugetlb_page(vma))) return hugetlb_fault(mm, vma, address, flags); @@ -3856,6 +3848,34 @@ retry: return handle_pte_fault(mm, vma, address, pte, pmd, flags); } +int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, unsigned int flags) +{ + int ret; + + __set_current_state(TASK_RUNNING); + + count_vm_event(PGFAULT); + mem_cgroup_count_vm_event(mm, PGFAULT); + + /* do counter updates before entering really critical section. */ + check_sync_rss_stat(current); + + /* + * Enable the memcg OOM handling for faults triggered in user + * space. Kernel faults are handled more gracefully. + */ + if (flags & FAULT_FLAG_USER) + mem_cgroup_enable_oom(); + + ret = __handle_mm_fault(mm, vma, address, flags); + + if (flags & FAULT_FLAG_USER) + mem_cgroup_disable_oom(); + + return ret; +} + #ifndef __PAGETABLE_PUD_FOLDED /* * Allocate page upper directory. |