- 15 Jan, 2016 40 commits
-
-
Vlastimil Babka authored
This series is based on Jerome Marchand's [1] so let me quote the first paragraph from there: There are several shortcomings with the accounting of shared memory (sysV shm, shared anonymous mapping, mapping to a tmpfs file). The values in /proc/<pid>/status and statm don't allow to distinguish between shmem memory and a shared mapping to a regular file, even though their implications on memory usage are quite different: at reclaim, file mapping can be dropped or written back on disk while shmem needs a place in swap. As for shmem pages that are swapped-out or in swap cache, they aren't accounted at all. The original motivation for myself is that a customer found (IMHO rightfully) confusing that e.g. top output for process swap usage is unreliable with respect to swapped out shmem pages, which are not accounted for. The fundamental difference between private anonymous and shmem pages is that the latter has PTE's converted to pte_none, and not swapents. As such, they are not accounted to the number of swapents visible e.g. in /proc/pid/status VmSwap row. It might be theoretically possible to use swapents when swapping out shmem (without extra cost, as one has to change all mappers anyway), and on swap in only convert the swapent for the faulting process, leaving swapents in other processes until they also fault (so again no extra cost). But I don't know how many assumptions this would break, and it would be too disruptive change for a relatively small benefit. Instead, my approach is to document the limitation of VmSwap, and provide means to determine the swap usage for shmem areas for those who are interested and willing to pay the price, using /proc/pid/smaps. Because outside of ipcs, I don't think it's possible to currently to determine the usage at all. The previous patchset [1] did introduce new shmem-specific fields into smaps output, and functions to determine the values. I take a simpler approach, noting that smaps output already has a "Swap: X kB" line, where currently X == 0 always for shmem areas. I think we can just consider this a bug and provide the proper value by consulting the radix tree, as e.g. mincore_page() does. In the patch changelog I explain why this is also not perfect (and cannot be without swapents), but still arguably much better than showing a 0. The last two patches are adapted from Jerome's patchset and provide a VmRSS breakdown to RssAnon, RssFile and RssShm in /proc/pid/status. Hugh noted that this is a welcome addition, and I agree that it might help e.g. debugging process memory usage at albeit non-zero, but still rather low cost of extra per-mm counter and some page flag checks. [1] http://lwn.net/Articles/611966/ This patch (of 6): The documentation for /proc/pid/status does not mention that the value of VmSwap counts only swapped out anonymous private pages, and not swapped out pages of the underlying shmem objects (for shmem mappings). This is not obvious, so document this limitation. Signed-off-by:
Vlastimil Babka <vbabka@suse.cz> Acked-by:
Konstantin Khlebnikov <khlebnikov@yandex-team.ru> Acked-by:
Michal Hocko <mhocko@suse.com> Acked-by:
Jerome Marchand <jmarchan@redhat.com> Acked-by:
Hugh Dickins <hughd@google.com> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
-
Yaowei Bai authored
Make memmap_valid_within return bool due to this particular function only using either one or zero as its return value. No functional change. Signed-off-by:
Yaowei Bai <baiyaowei@cmss.chinamobile.com> Signed-off-by:
-
Geliang Tang authored
To make the intention clearer, use list_{next,first}_entry instead of list_entry. Signed-off-by:Geliang Tang <geliangtang@163.com> Signed-off-by:
-
Michal Hocko authored
__alloc_pages_slowpath is looping over ALLOC_NO_WATERMARKS requests if __GFP_NOFAIL is requested. This is fragile because we are basically relying on somebody else to make the reclaim (be it the direct reclaim or OOM killer) for us. The caller might be holding resources (e.g. locks) which block other other reclaimers from making any progress for example. Remove the retry loop and rely on __alloc_pages_slowpath to invoke all allowed reclaim steps and retry logic. We have to be careful about __GFP_NOFAIL allocations from the PF_MEMALLOC context even though this is a very bad idea to begin with because no progress can be gurateed at all. We shouldn't break the __GFP_NOFAIL semantic here though. It could be argued that this is essentially GFP_NOWAIT context which we do not support but PF_MEMALLOC is much harder to check for existing users because they might happen deep down the code path performed much later after setting the flag so we cannot really rule out there is no kernel path triggering this combination. Signed-off-by:
Mel Gorman <mgorman@suse.de> Acked-by:
David Rientjes <rientjes@google.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Acked-by:
-
Michal Hocko authored
__alloc_pages_high_priority doesn't do anything special other than it calls get_page_from_freelist and loops around GFP_NOFAIL allocation until it succeeds. It would be better if the first part was done in __alloc_pages_slowpath where we modify the zonelist because this would be easier to read and understand. Opencoding the function into its only caller allows to simplify it a bit as well. This patch doesn't introduce any functional changes. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:
-
Yaowei Bai authored
Hardcoding index to zonelists array in gfp_zonelist() is not a good idea, let's enumerate it to improve readability. No functional change. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix CONFIG_NUMA=n build] [n-horiguchi@ah.jp.nec.com: fix warning in comparing enumerator] Signed-off-by:
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by:
-
Yaowei Bai authored
Since commit a0b8cab3 ("mm: remove lru parameter from __pagevec_lru_add and remove parts of pagevec API") there's no user of this function anymore, so remove it. Signed-off-by:
Hillf Danton <hillf.zj@alibaba-inc.com> Signed-off-by:
-
Yaowei Bai authored
Make memblock_is_memory() and memblock_is_reserved return bool to improve readability due to these particular functions only using either one or zero as their return value. No functional change. Signed-off-by:
-
Yaowei Bai authored
Make is_file_hugepages() return bool to improve readability due to this particular function only using either one or zero as its return value. This patch also removed the if condition to make is_file_hugepages return directly. No functional change. Signed-off-by:
-
yalin wang authored
Move node_id zone_idx shrink flags into trace function, so thay we don't need caculate these args if the trace is disabled, and will make this function have less arguments. Signed-off-by:
yalin wang <yalin.wang2010@gmail.com> Reviewed-by:
Steven Rostedt <rostedt@goodmis.org> Acked-by:
-
Joonsoo Kim authored
Now, we have tracepoint in test_pages_isolated() to notify pfn which cannot be isolated. But, in alloc_contig_range(), some error path doesn't call test_pages_isolated() so it's still hard to know exact pfn that causes allocation failure. This patch change this situation by calling test_pages_isolated() in almost error path. In allocation failure case, some overhead is added by this change, but, allocation failure is really rare event so it would not matter. In fatal signal pending case, we don't call test_pages_isolated() because this failure is intentional one. There was a bogus outer_start problem due to unchecked buddy order and this patch also fix it. Before this patch, it didn't matter, because end result is same thing. But, after this patch, tracepoint will report failed pfn so it should be accurate. Signed-off-by:
Joonsoo Kim <iamjoonsoo.kim@lge.com> Acked-by:
Michal Nazarewicz <mina86@mina86.com> Cc: David Rientjes <rientjes@google.com> Cc: Minchan Kim <minchan@kernel.org> Signed-off-by:
-
Joonsoo Kim authored
cma allocation should be guranteeded to succeed. But sometimes it can fail in the current implementation. To track down the problem, we need to know which page is problematic and this new tracepoint will report it. Signed-off-by:
-
Joonsoo Kim authored
This is preparation step to report test failed pfn in new tracepoint to analyze cma allocation failure problem. There is no functional change in this patch. Signed-off-by:
-
Nathan Zimmer authored
When running the SPECint_rate gcc on some very large boxes it was noticed that the system was spending lots of time in mpol_shared_policy_lookup(). The gamess benchmark can also show it and is what I mostly used to chase down the issue since the setup for that I found to be easier. To be clear the binaries were on tmpfs because of disk I/O requirements. We then used text replication to avoid icache misses and having all the copies banging on the memory where the instruction code resides. This results in us hitting a bottleneck in mpol_shared_policy_lookup() since lookup is serialised by the shared_policy lock. I have only reproduced this on very large (3k+ cores) boxes. The problem starts showing up at just a few hundred ranks getting worse until it threatens to livelock once it gets large enough. For example on the gamess benchmark at 128 ranks this area consumes only ~1% of time, at 512 ranks it consumes nearly 13%, and at 2k ranks it is over 90%. To alleviate the contention in this area I converted the spinlock to an rwlock. This allows a large number of lookups to happen simultaneously. The results were quite good reducing this consumtion at max ranks to around 2%. [akpm@linux-foundation.org: tidy up code comments] Signed-off-by:
Nathan Zimmer <nzimmer@sgi.com> Acked-by:
-
Chen Gang authored
__phys_to_pfn and __pfn_to_phys are symmetric, PHYS_PFN and PFN_PHYS are semmetric: - y = (phys_addr_t)x << PAGE_SHIFT - y >> PAGE_SHIFT = (phys_add_t)x - (unsigned long)(y >> PAGE_SHIFT) = x [akpm@linux-foundation.org: use macro arg name `x'] [arnd@arndb.de: include linux/pfn.h for PHYS_PFN definition] Signed-off-by:
Chen Gang <gang.chen.5i5j@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Signed-off-by:
Arnd Bergmann <arnd@arndb.de> Signed-off-by:
-
yalin wang authored
Move trace_reclaim_flags() into trace function, so that we don't need caculate these flags if the trace is disabled. Signed-off-by:
-
Chen Gang authored
Simplify may_expand_vm(). [akpm@linux-foundation.org: further simplification, per Naoya Horiguchi] Signed-off-by:
-
Alexey Klimov authored
Before usage page pointer initialized by NULL is reinitialized by follow_page_mask(). Drop useless init of page pointer in the beginning of loop. Signed-off-by:
Alexey Klimov <klimov.linux@gmail.com> Acked-by:
-
Vladimir Davydov authored
Mark those kmem allocations that are known to be easily triggered from userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to memcg. For the list, see below: - threadinfo - task_struct - task_delay_info - pid - cred - mm_struct - vm_area_struct and vm_region (nommu) - anon_vma and anon_vma_chain - signal_struct - sighand_struct - fs_struct - files_struct - fdtable and fdtable->full_fds_bits - dentry and external_name - inode for all filesystems. This is the most tedious part, because most filesystems overwrite the alloc_inode method. The list is far from complete, so feel free to add more objects. Nevertheless, it should be close to "account everything" approach and keep most workloads within bounds. Malevolent users will be able to breach the limit, but this was possible even with the former "account everything" approach (simply because it did not account everything in fact). [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:
Vladimir Davydov <vdavydov@virtuozzo.com> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Acked-by:
-
Vladimir Davydov authored
Make vmalloc family functions allocate vmalloc area pages with alloc_kmem_pages so that if __GFP_ACCOUNT is set they will be accounted to memcg. This is needed, at least, to account alloc_fdmem allocations. Signed-off-by:
-
Vladimir Davydov authored
Currently, if we want to account all objects of a particular kmem cache, we have to pass __GFP_ACCOUNT to each kmem_cache_alloc call, which is inconvenient. This patch introduces SLAB_ACCOUNT flag which if passed to kmem_cache_create will force accounting for every allocation from this cache even if __GFP_ACCOUNT is not passed. This patch does not make any of the existing caches use this flag - it will be done later in the series. Note, a cache with SLAB_ACCOUNT cannot be merged with a cache w/o SLAB_ACCOUNT, because merged caches share the same kmem_cache struct and hence cannot have different sets of SLAB_* flags. Thus using this flag will probably reduce the number of merged slabs even if kmem accounting is not used (only compiled in). Signed-off-by:
Tejun Heo <tj@kernel.org> Acked-by:
-
Vladimir Davydov authored
Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be fragile and difficult to maintain, because there seem to be many more allocations that should not be accounted than those that should be. Besides, false accounting an allocation might result in much worse consequences than not accounting at all, namely increased memory consumption due to pinned dead kmem caches. So this patch switches kmem accounting to the white-policy: now only those kmem allocations that are marked as __GFP_ACCOUNT are accounted to memcg. Currently, no kmem allocations are marked like this. The following patches will mark several kmem allocations that are known to be easily triggered from userspace and therefore should be accounted to memcg. Signed-off-by:
-
Vladimir Davydov authored
This reverts commit 8f4fc071 ("gfp: add __GFP_NOACCOUNT"). Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be fragile and difficult to maintain, because there seem to be many more allocations that should not be accounted than those that should be. Besides, false accounting an allocation might result in much worse consequences than not accounting at all, namely increased memory consumption due to pinned dead kmem caches. So it was decided to switch to the white-list policy. This patch reverts bits introducing the black-list policy. The white-list policy will be introduced later in the series. Signed-off-by:
-
Vladimir Davydov authored
Currently, all kmem allocations (namely every kmem_cache_alloc, kmalloc, alloc_kmem_pages call) are accounted to memory cgroup automatically. Callers have to explicitly opt out if they don't want/need accounting for some reason. Such a design decision leads to several problems: - kmalloc users are highly sensitive to failures, many of them implicitly rely on the fact that kmalloc never fails, while memcg makes failures quite plausible. - A lot of objects are shared among different containers by design. Accounting such objects to one of containers is just unfair. Moreover, it might lead to pinning a dead memcg along with its kmem caches, which aren't tiny, which might result in noticeable increase in memory consumption for no apparent reason in the long run. - There are tons of short-lived objects. Accounting them to memcg will only result in slight noise and won't change the overall picture, but we still have to pay accounting overhead. For more info, see - http://lkml.kernel.org/r/20151105144002.GB15111%40dhcp22.suse.cz - http://lkml.kernel.org/r/20151106090555.GK29259@esperanza Therefore this patchset switches to the white list policy. Now kmalloc users have to explicitly opt in by passing __GFP_ACCOUNT flag. Currently, the list of accounted objects is quite limited and only includes those allocations that (1) are known to be easily triggered from userspace and (2) can fail gracefully (for the full list see patch no. 6) and it still misses many object types. However, accounting only those objects should be a satisfactory approximation of the behavior we used to have for most sane workloads. This patch (of 6): Revert 499611ed ("kernfs: do not account ino_ida allocations to memcg"). Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be fragile and difficult to maintain, because there seem to be many more allocations that should not be accounted than those that should be. Besides, false accounting an allocation might result in much worse consequences than not accounting at all, namely increased memory consumption due to pinned dead kmem caches. So it was decided to switch to the white-list policy. This patch reverts bits introducing the black-list policy. The white-list policy will be introduced later in the series. Signed-off-by:
-
Geliang Tang authored
Add a new helper function get_first_slab() that get the first slab from a kmem_cache_node. Signed-off-by:
Christoph Lameter <cl@linux.com> Acked-by:
-
Geliang Tang authored
Simplify the code with list_for_each_entry(). Signed-off-by:
-
Geliang Tang authored
Simplify the code with list_first_entry_or_null(). Signed-off-by:
-
Andrew Morton authored
A little cleanup - the invocation site provdes the semicolon. Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by:
-
Joseph Qi authored
lksb flags are defined both in dlmapi.h and dlmcommon.h. So clean them up from dlmcommon.h. Signed-off-by:
Joseph Qi <joseph.qi@huawei.com> Reviewed-by:
Jiufei Xue <xuejiufei@huawei.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Signed-off-by:
-
Junxiao Bi authored
Found this when do patch review, remove to make it clear and save a little cpu time. Signed-off-by:
Junxiao Bi <junxiao.bi@oracle.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Cc: Joseph Qi <joseph.qi@huawei.com> Signed-off-by:
-
Joseph Qi authored
In ocfs2_orphan_del, currently it finds and deletes entry first, and then access orphan dir dinode. This will have a problem once ocfs2_journal_access_di fails. In this case, entry will be removed from orphan dir, but in deed the inode hasn't been deleted successfully. In other words, the file is missing but not actually deleted. So we should access orphan dinode first like unlink and rename. Signed-off-by:
-
xuejiufei authored
When two processes are migrating the same lockres, dlm_add_migration_mle() return -EEXIST, but insert a new mle in hash list. dlm_migrate_lockres() will detach the old mle and free the new one which is already in hash list, that will destroy the list. Signed-off-by:
-
xuejiufei authored
We have found that migration source will trigger a BUG that the refcount of mle is already zero before put when the target is down during migration. The situation is as follows: dlm_migrate_lockres dlm_add_migration_mle dlm_mark_lockres_migrating dlm_get_mle_inuse <<<<<< Now the refcount of the mle is 2. dlm_send_one_lockres and wait for the target to become the new master. <<<<<< o2hb detect the target down and clean the migration mle. Now the refcount is 1. dlm_migrate_lockres woken, and put the mle twice when found the target goes down which trigger the BUG with the following message: "ERROR: bad mle: ". Signed-off-by:
-
Goldwyn Rodrigues authored
DLM does not cache locks. So, blocking lock and unlock will only make the performance worse where contention over the locks is high. Signed-off-by:
Goldwyn Rodrigues <rgoldwyn@suse.com> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Reviewed-by:
-
jiangyiwen authored
The following case will lead to slot overwritten. N1 N2 mount ocfs2 volume, find and allocate slot 0, then set osb->slot_num to 0, begin to write slot info to disk mount ocfs2 volume, wait for super lock write block fail because of storage link down, unlock super lock got super lock and also allocate slot 0 then unlock super lock mount fail and then dismount, since osb->slot_num is 0, try to put invalid slot to disk. And it will succeed if storage link restores. N2 slot info is now overwritten Once another node say N3 mount, it will find and allocate slot 0 again, which will lead to mount hung because journal has already been locked by N2. so when write slot info failed, invalidate slot in advance to avoid overwrite slot. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:Yiwen Jiang <jiangyiwen@huawei.com> Reviewed-by:
-
Xue jiufei authored
dlm_grab() may return NULL when the node is doing unmount. When doing code review, we found that some dlm handlers may return error to caller when dlm_grab() returns NULL and make caller BUG or other problems. Here is an example: Node 1 Node 2 receives migration message from node 3, and send migrate request to others start unmounting receives migrate request from node 1 and call dlm_migrate_request_handler() unmount thread unregisters domain handlers and removes dlm_context from dlm_domains dlm_migrate_request_handlers() returns -EINVAL to node 1 Exit migration neither clearing the migration state nor sending assert master message to node 3 which cause node 3 hung. Signed-off-by: -
Joseph Qi authored
Since iput will take care the NULL check itself, NULL check before calling it is redundant. So clean them up. Signed-off-by:
-
jiangyiwen authored
Commit f3f85464 ("ocfs2_dlm: Ensure correct ordering of set/clear refmap bit on lockres") still exists a race which can't ensure the ordering is exactly correct. Node1 Node2 Node3 umount, migrate lockres to Node2 migrate finished, send migrate request to Node3 received migrate request, create a migration_mle, respond to Node2. set DLM_LOCK_RES_SETREF_INPROG and send assert master to Node3 delete migration_mle in assert_master_handler, Node3 umount without response dlm_thread purge this lockres, send drop deref message to Node2 found the flag of DLM_LOCK_RES_SETREF_INPROG is set, dispatch dlm_deref_lockres_worker to clear refmap, but in function of dlm_deref_lockres_worker, only if node in refmap it wait DLM_LOCK_RES_SETREF_INPROG to be cleared. So worker is done successfully purge lockres, send assert master response to Node1, and finish umount set Node3 in refmap, and it won't be cleared forever, thus lead to umount hung so wait until DLM_LOCK_RES_SETREF_INPROG is cleared in dlm_deref_lockres_worker. Signed-off-by:
-
Julia Lawall authored
The ocfs2_extent_tree_operations structures are never modified, so declare them as const. Done with the help of Coccinelle. Signed-off-by:
Julia Lawall <Julia.Lawall@lip6.fr> Cc: Mark Fasheh <mfasheh@suse.de> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by:
-
Xue jiufei authored
We found a race between purge and migration when doing code review. Node A put lockres to purgelist before receiving the migrate message from node B which is the master. Node A call dlm_mig_lockres_handler to handle this message. dlm_mig_lockres_handler dlm_lookup_lockres >>>>>> race window, dlm_run_purge_list may run and send deref message to master, waiting the response spin_lock(&res->spinlock); res->state |= DLM_LOCK_RES_MIGRATING; spin_unlock(&res->spinlock); dlm_mig_lockres_handler returns >>>>>> dlm_thread receives the response from master for the deref message and triggers the BUG because the lockres has the state DLM_LOCK_RES_MIGRATING with the following message: dlm_purge_lockres:209 ERROR: 6633EB681FA7474A9C280A4E1A836F0F: res M0000000000000000030c0300000000 in use after deref Signed-off-by:
-
