- 06 Nov, 2021 40 commits
-
-
Christophe Leroy authored
The generic version of arch_is_kernel_initmem_freed() now does the same as s390 version. Remove the s390 version. Link: https://lkml.kernel.org/r/b6feb5dfe611a322de482762fc2df3a9eece70c7.1633001016.git.christophe.leroy@csgroup.euSigned-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Acked-by: Heiko Carstens <hca@linux.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Christophe Leroy authored
The generic version of arch_is_kernel_initmem_freed() now does the same as powerpc version. Remove the powerpc version. Link: https://lkml.kernel.org/r/c53764eb45d41491e2b21da2e7812239897dbebb.1633001016.git.christophe.leroy@csgroup.euSigned-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Christophe Leroy authored
Commit 7a5da02d ("locking/lockdep: check for freed initmem in static_obj()") added arch_is_kernel_initmem_freed() which is supposed to report whether an object is part of already freed init memory. For the time being, the generic version of arch_is_kernel_initmem_freed() always reports 'false', allthough free_initmem() is generically called on all architectures. Therefore, change the generic version of arch_is_kernel_initmem_freed() to check whether free_initmem() has been called. If so, then check if a given address falls into init memory. To ease the use of system_state, move it out of line into its only caller which is lockdep.c Link: https://lkml.kernel.org/r/1d40783e676e07858be97d881f449ee7ea8adfb1.1633001016.git.christophe.leroy@csgroup.euSigned-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Heiko Carstens <hca@linux.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Christophe Leroy authored
core_kernel_text() considers that until system_state in at least SYSTEM_RUNNING, init memory is valid. But init memory is freed a few lines before setting SYSTEM_RUNNING, so we have a small period of time when core_kernel_text() is wrong. Create an intermediate system state called SYSTEM_FREEING_INIT that is set before starting freeing init memory, and use it in core_kernel_text() to report init memory invalid earlier. Link: https://lkml.kernel.org/r/9ecfdee7dd4d741d172cb93ff1d87f1c58127c9a.1633001016.git.christophe.leroy@csgroup.euSigned-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Liangcai Fan authored
min/low/high_wmark_pages(z) is defined as (z->_watermark[WMARK_MIN/LOW/HIGH] + z->watermark_boost) If kswapd is frequently woken up due to the increase of min/low/high_wmark_pages, printing watermark_boost can quickly locate whether watermark_boost or _watermark[WMARK_MIN/LOW/HIGH] caused min/low/high_wmark_pages to increase. Link: https://lkml.kernel.org/r/1632472566-12246-1-git-send-email-liangcaifan19@gmail.comSigned-off-by: Liangcai Fan <liangcaifan19@gmail.com> Cc: Chunyan Zhang <zhang.lyra@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Feng Tang authored
There was a report that starting an Ubuntu in docker while using cpuset to bind it to movable nodes (a node only has movable zone, like a node for hotplug or a Persistent Memory node in normal usage) will fail due to memory allocation failure, and then OOM is involved and many other innocent processes got killed. It can be reproduced with command: $ docker run -it --rm --cpuset-mems 4 ubuntu:latest bash -c "grep Mems_allowed /proc/self/status" (where node 4 is a movable node) runc:[2:INIT] invoked oom-killer: gfp_mask=0x500cc2(GFP_HIGHUSER|__GFP_ACCOUNT), order=0, oom_score_adj=0 CPU: 8 PID: 8291 Comm: runc:[2:INIT] Tainted: G W I E 5.8.2-0.g71b519a-default #1 openSUSE Tumbleweed (unreleased) Hardware name: Dell Inc. PowerEdge R640/0PHYDR, BIOS 2.6.4 04/09/2020 Call Trace: dump_stack+0x6b/0x88 dump_header+0x4a/0x1e2 oom_kill_process.cold+0xb/0x10 out_of_memory.part.0+0xaf/0x230 out_of_memory+0x3d/0x80 __alloc_pages_slowpath.constprop.0+0x954/0xa20 __alloc_pages_nodemask+0x2d3/0x300 pipe_write+0x322/0x590 new_sync_write+0x196/0x1b0 vfs_write+0x1c3/0x1f0 ksys_write+0xa7/0xe0 do_syscall_64+0x52/0xd0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Mem-Info: active_anon:392832 inactive_anon:182 isolated_anon:0 active_file:68130 inactive_file:151527 isolated_file:0 unevictable:2701 dirty:0 writeback:7 slab_reclaimable:51418 slab_unreclaimable:116300 mapped:45825 shmem:735 pagetables:2540 bounce:0 free:159849484 free_pcp:73 free_cma:0 Node 4 active_anon:1448kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB isolated(anon):0kB isolated(file):0kB mapped:0kB dirty:0kB writeback:0kB shmem:0kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB all_unreclaimable? no Node 4 Movable free:130021408kB min:9140kB low:139160kB high:269180kB reserved_highatomic:0KB active_anon:1448kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:130023424kB managed:130023424kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:292kB local_pcp:84kB free_cma:0kB lowmem_reserve[]: 0 0 0 0 0 Node 4 Movable: 1*4kB (M) 0*8kB 0*16kB 1*32kB (M) 0*64kB 0*128kB 1*256kB (M) 1*512kB (M) 1*1024kB (M) 0*2048kB 31743*4096kB (M) = 130021156kB oom-kill:constraint=CONSTRAINT_CPUSET,nodemask=(null),cpuset=docker-9976a269caec812c134fa317f27487ee36e1129beba7278a463dd53e5fb9997b.scope,mems_allowed=4,global_oom,task_memcg=/system.slice/containerd.service,task=containerd,pid=4100,uid=0 Out of memory: Killed process 4100 (containerd) total-vm:4077036kB, anon-rss:51184kB, file-rss:26016kB, shmem-rss:0kB, UID:0 pgtables:676kB oom_score_adj:0 oom_reaper: reaped process 8248 (docker), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB oom_reaper: reaped process 2054 (node_exporter), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB oom_reaper: reaped process 1452 (systemd-journal), now anon-rss:0kB, file-rss:8564kB, shmem-rss:4kB oom_reaper: reaped process 2146 (munin-node), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB oom_reaper: reaped process 8291 (runc:[2:INIT]), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB The reason is that in this case, the target cpuset nodes only have movable zone, while the creation of an OS in docker sometimes needs to allocate memory in non-movable zones (dma/dma32/normal) like GFP_HIGHUSER, and the cpuset limit forbids the allocation, then out-of-memory killing is involved even when normal nodes and movable nodes both have many free memory. The OOM killer cannot help to resolve the situation as there is no usable memory for the request in the cpuset scope. The only reasonable measure to take is to fail the allocation right away and have the caller to deal with it. So add a check for cases like this in the slowpath of allocation, and bail out early returning NULL for the allocation. As page allocation is one of the hottest path in kernel, this check will hurt all users with sane cpuset configuration, add a static branch check and detect the abnormal config in cpuset memory binding setup so that the extra check cost in page allocation is not paid by everyone. [thanks to Micho Hocko and David Rientjes for suggesting not handling it inside OOM code, adding cpuset check, refining comments] Link: https://lkml.kernel.org/r/1632481657-68112-1-git-send-email-feng.tang@intel.comSigned-off-by: Feng Tang <feng.tang@intel.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: David Rientjes <rientjes@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zefan Li <lizefan.x@bytedance.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Eric Dumazet authored
Grabbing zone lock in is_free_buddy_page() gives a wrong sense of safety, and has potential performance implications when zone is experiencing lock contention. In any case, if a caller needs a stable result, it should grab zone lock before calling this function. Link: https://lkml.kernel.org/r/20210922152833.4023972-1-eric.dumazet@gmail.comSigned-off-by: Eric Dumazet <edumazet@google.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>
-
Geert Uytterhoeven authored
If CONFIG_NUMA=y, but CONFIG_SMP=n (e.g. sh/migor_defconfig): sh4-linux-gnu-ld: mm/vmstat.o: in function `vmstat_start': vmstat.c:(.text+0x97c): undefined reference to `fold_vm_numa_events' sh4-linux-gnu-ld: drivers/base/node.o: in function `node_read_vmstat': node.c:(.text+0x140): undefined reference to `fold_vm_numa_events' sh4-linux-gnu-ld: drivers/base/node.o: in function `node_read_numastat': node.c:(.text+0x1d0): undefined reference to `fold_vm_numa_events' Fix this by moving fold_vm_numa_events() outside the SMP-only section. Link: https://lkml.kernel.org/r/9d16ccdd9ef32803d7100c84f737de6a749314fb.1631781495.git.geert+renesas@glider.be Fixes: f19298b9 ("mm/vmstat: convert NUMA statistics to basic NUMA counters") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Gon Solo <gonsolo@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rich Felker <dalias@libc.org> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yoshinori Sato <ysato@users.osdn.me> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Geert Uytterhoeven authored
Patch series "Fix NUMA without SMP". SuperH is the only architecture which still supports NUMA without SMP, for good reasons (various memories scattered around the address space, each with varying latencies). This series fixes two build errors due to variables and functions used by the NUMA code being provided by SMP-only source files or sections. This patch (of 2): If CONFIG_NUMA=y, but CONFIG_SMP=n (e.g. sh/migor_defconfig): sh4-linux-gnu-ld: mm/page_alloc.o: in function `get_page_from_freelist': page_alloc.c:(.text+0x2c24): undefined reference to `node_reclaim_distance' Fix this by moving the declaration of node_reclaim_distance from an SMP-only to a generic file. Link: https://lkml.kernel.org/r/cover.1631781495.git.geert+renesas@glider.be Link: https://lkml.kernel.org/r/6432666a648dde85635341e6c918cee97c97d264.1631781495.git.geert+renesas@glider.be Fixes: a55c7454 ("sched/topology: Improve load balancing on AMD EPYC systems") Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Suggested-by: Matt Fleming <matt@codeblueprint.co.uk> Acked-by: Mel Gorman <mgorman@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yoshinori Sato <ysato@users.osdn.me> Cc: Rich Felker <dalias@libc.org> Cc: Gon Solo <gonsolo@gmail.com> Cc: Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Krupa Ramakrishnan authored
In build_zonelists(), when the fallback list is built for the nodes, the node load gets reinitialized during each iteration. This results in nodes with same distances occupying the same slot in different node fallback lists rather than appearing in the intended round- robin manner. This results in one node getting picked for allocation more compared to other nodes with the same distance. As an example, consider a 4 node system with the following distance matrix. Node 0 1 2 3 ---------------- 0 10 12 32 32 1 12 10 32 32 2 32 32 10 12 3 32 32 12 10 For this case, the node fallback list gets built like this: Node Fallback list --------------------- 0 0 1 2 3 1 1 0 3 2 2 2 3 0 1 3 3 2 0 1 <-- Unexpected fallback order In the fallback list for nodes 2 and 3, the nodes 0 and 1 appear in the same order which results in more allocations getting satisfied from node 0 compared to node 1. The effect of this on remote memory bandwidth as seen by stream benchmark is shown below: Case 1: Bandwidth from cores on nodes 2 & 3 to memory on nodes 0 & 1 (numactl -m 0,1 ./stream_lowOverhead ... --cores <from 2, 3>) Case 2: Bandwidth from cores on nodes 0 & 1 to memory on nodes 2 & 3 (numactl -m 2,3 ./stream_lowOverhead ... --cores <from 0, 1>) ---------------------------------------- BANDWIDTH (MB/s) TEST Case 1 Case 2 ---------------------------------------- COPY 57479.6 110791.8 SCALE 55372.9 105685.9 ADD 50460.6 96734.2 TRIADD 50397.6 97119.1 ---------------------------------------- The bandwidth drop in Case 1 occurs because most of the allocations get satisfied by node 0 as it appears first in the fallback order for both nodes 2 and 3. This can be fixed by accumulating the node load in build_zonelists() rather than reinitializing it during each iteration. With this the nodes with the same distance rightly get assigned in the round robin manner. In fact this was how it was originally until commit f0c0b2b8 ("change zonelist order: zonelist order selection logic") dropped the load accumulation and resorted to initializing the load during each iteration. While zonelist ordering was removed by commit c9bff3ee ("mm, page_alloc: rip out ZONELIST_ORDER_ZONE"), the change to the node load accumulation in build_zonelists() remained. So essentially this patch reverts back to the accumulated node load logic. After this fix, the fallback order gets built like this: Node Fallback list ------------------ 0 0 1 2 3 1 1 0 3 2 2 2 3 0 1 3 3 2 1 0 <-- Note the change here The bandwidth in Case 1 improves and matches Case 2 as shown below. ---------------------------------------- BANDWIDTH (MB/s) TEST Case 1 Case 2 ---------------------------------------- COPY 110438.9 110107.2 SCALE 105930.5 105817.5 ADD 97005.1 96159.8 TRIADD 97441.5 96757.1 ---------------------------------------- The correctness of the fallback list generation has been verified for the above node configuration where the node 3 starts as memory-less node and comes up online only during memory hotplug. [bharata@amd.com: Added changelog, review, test validation] Link: https://lkml.kernel.org/r/20210830121603.1081-3-bharata@amd.com Fixes: f0c0b2b8 ("change zonelist order: zonelist order selection logic") Signed-off-by: Krupa Ramakrishnan <krupa.ramakrishnan@amd.com> Co-developed-by: Sadagopan Srinivasan <Sadagopan.Srinivasan@amd.com> Signed-off-by: Sadagopan Srinivasan <Sadagopan.Srinivasan@amd.com> Signed-off-by: Bharata B Rao <bharata@amd.com> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Bharata B Rao authored
Patch series "Fix NUMA nodes fallback list ordering". For a NUMA system that has multiple nodes at same distance from other nodes, the fallback list generation prefers same node order for them instead of round-robin thereby penalizing one node over others. This series fixes it. More description of the problem and the fix is present in the patch description. This patch (of 2): Print information message about the allocation fallback order for each NUMA node during boot. No functional changes here. This makes it easier to illustrate the problem in the node fallback list generation, which the next patch fixes. Link: https://lkml.kernel.org/r/20210830121603.1081-1-bharata@amd.com Link: https://lkml.kernel.org/r/20210830121603.1081-2-bharata@amd.comSigned-off-by: Bharata B Rao <bharata@amd.com> Acked-by: Mel Gorman <mgorman@suse.de> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: Lee Schermerhorn <lee.schermerhorn@hp.com> Cc: Krupa Ramakrishnan <krupa.ramakrishnan@amd.com> Cc: Sadagopan Srinivasan <Sadagopan.Srinivasan@amd.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Miaohe Lin authored
Don't use with __GFP_HIGHMEM because page_address() cannot represent highmem pages without kmap(). Newly allocated pages would leak as page_address() will return NULL for highmem pages here. But It works now because the callers do not specify __GFP_HIGHMEM now. Link: https://lkml.kernel.org/r/20210902121242.41607-6-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Miaohe Lin authored
Use helper function zone_spans_pfn() to check whether pfn is within a zone to simplify the code slightly. Link: https://lkml.kernel.org/r/20210902121242.41607-5-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Miaohe Lin authored
The second two paragraphs about "all pages pinned" and pages_scanned is obsolete. And There are PAGE_ALLOC_COSTLY_ORDER + 1 + NR_PCP_THP orders in pcp. So the same order assumption is not held now. Link: https://lkml.kernel.org/r/20210902121242.41607-4-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Cc: David Hildenbrand <david@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Miaohe Lin authored
Use helper macro K() to convert the pages to the corresponding size. Minor readability improvement. Link: https://lkml.kernel.org/r/20210902121242.41607-3-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Miaohe Lin authored
Patch series "Cleanups and fixup for page_alloc", v2. This series contains cleanups to remove meaningless VM_BUG_ON(), use helpers to simplify the code and remove obsolete comment. Also we avoid allocating highmem pages via alloc_pages_exact[_nid]. More details can be found in the respective changelogs. This patch (of 5): It's meaningless to VM_BUG_ON() order != pageblock_order just after setting order to pageblock_order. Remove it. Link: https://lkml.kernel.org/r/20210902121242.41607-1-linmiaohe@huawei.com Link: https://lkml.kernel.org/r/20210902121242.41607-2-linmiaohe@huawei.comSigned-off-by: Miaohe Lin <linmiaohe@huawei.com> Acked-by: Mel Gorman <mgorman@techsingularity.net> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Eric Dumazet authored
If __vmalloc() returned NULL, is_vm_area_hugepages(NULL) will fault if CONFIG_HAVE_ARCH_HUGE_VMALLOC=y Link: https://lkml.kernel.org/r/20210915212530.2321545-1-eric.dumazet@gmail.com Fixes: 121e6f32 ("mm/vmalloc: hugepage vmalloc mappings") Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Changcheng Deng authored
Use swap() in order to make code cleaner. Issue found by coccinelle. Link: https://lkml.kernel.org/r/20211028111443.15744-1-deng.changcheng@zte.com.cnSigned-off-by: Changcheng Deng <deng.changcheng@zte.com.cn> Reported-by: Zeal Robot <zealci@zte.com.cn> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Chen Wandun authored
Commit ffb29b1c ("mm/vmalloc: fix numa spreading for large hash tables") can cause significant performance regressions in some situations as Andrew mentioned in [1]. The main situation is vmalloc, vmalloc will allocate pages with NUMA_NO_NODE by default, that will result in alloc page one by one; In order to solve this, __alloc_pages_bulk and mempolicy should be considered at the same time. 1) If node is specified in memory allocation request, it will alloc all pages by __alloc_pages_bulk. 2) If interleaving allocate memory, it will cauculate how many pages should be allocated in each node, and use __alloc_pages_bulk to alloc pages in each node. [1]: https://lore.kernel.org/lkml/CALvZod4G3SzP3kWxQYn0fj+VgG-G3yWXz=gz17+3N57ru1iajw@mail.gmail.com/t/#m750c8e3231206134293b089feaa090590afa0f60 [akpm@linux-foundation.org: coding style fixes] [akpm@linux-foundation.org: make two functions static] [akpm@linux-foundation.org: fix CONFIG_NUMA=n build] Link: https://lkml.kernel.org/r/20211021080744.874701-3-chenwandun@huawei.comSigned-off-by: Chen Wandun <chenwandun@huawei.com> Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Eric Dumazet <edumazet@google.com> Cc: Shakeel Butt <shakeelb@google.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Michal Hocko authored
The core of the vmalloc allocator __vmalloc_area_node doesn't say anything about gfp mask argument. Not all gfp flags are supported though. Be more explicit about constraints. Link: https://lkml.kernel.org/r/20211020082545.4830-1-mhocko@kernel.orgSigned-off-by: Michal Hocko <mhocko@suse.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: Ilya Dryomov <idryomov@gmail.com> Cc: Jeff Layton <jlayton@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Kefeng Wang authored
With KASAN_VMALLOC and NEED_PER_CPU_PAGE_FIRST_CHUNK the kernel crashes: Unable to handle kernel paging request at virtual address ffff7000028f2000 ... swapper pgtable: 64k pages, 48-bit VAs, pgdp=0000000042440000 [ffff7000028f2000] pgd=000000063e7c0003, p4d=000000063e7c0003, pud=000000063e7c0003, pmd=000000063e7b0003, pte=0000000000000000 Internal error: Oops: 96000007 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 0 Comm: swapper Not tainted 5.13.0-rc4-00003-gc6e6e28f3f30-dirty #62 Hardware name: linux,dummy-virt (DT) pstate: 200000c5 (nzCv daIF -PAN -UAO -TCO BTYPE=--) pc : kasan_check_range+0x90/0x1a0 lr : memcpy+0x88/0xf4 sp : ffff80001378fe20 ... Call trace: kasan_check_range+0x90/0x1a0 pcpu_page_first_chunk+0x3f0/0x568 setup_per_cpu_areas+0xb8/0x184 start_kernel+0x8c/0x328 The vm area used in vm_area_register_early() has no kasan shadow memory, Let's add a new kasan_populate_early_vm_area_shadow() function to populate the vm area shadow memory to fix the issue. [wangkefeng.wang@huawei.com: fix redefinition of 'kasan_populate_early_vm_area_shadow'] Link: https://lkml.kernel.org/r/20211011123211.3936196-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20210910053354.26721-4-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Acked-by: Marco Elver <elver@google.com> [KASAN] Acked-by: Andrey Konovalov <andreyknvl@gmail.com> [KASAN] Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Kefeng Wang authored
Percpu embedded first chunk allocator is the firstly option, but it could fails on ARM64, eg, percpu: max_distance=0x5fcfdc640000 too large for vmalloc space 0x781fefff0000 percpu: max_distance=0x600000540000 too large for vmalloc space 0x7dffb7ff0000 percpu: max_distance=0x5fff9adb0000 too large for vmalloc space 0x5dffb7ff0000 then we could get WARNING: CPU: 15 PID: 461 at vmalloc.c:3087 pcpu_get_vm_areas+0x488/0x838 and the system could not boot successfully. Let's implement page mapping percpu first chunk allocator as a fallback to the embedding allocator to increase the robustness of the system. Link: https://lkml.kernel.org/r/20210910053354.26721-3-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Marco Elver <elver@google.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Kefeng Wang authored
Percpu embedded first chunk allocator is the firstly option, but it could fail on ARM64, eg, percpu: max_distance=0x5fcfdc640000 too large for vmalloc space 0x781fefff0000 percpu: max_distance=0x600000540000 too large for vmalloc space 0x7dffb7ff0000 percpu: max_distance=0x5fff9adb0000 too large for vmalloc space 0x5dffb7ff0000 then we could get to WARNING: CPU: 15 PID: 461 at vmalloc.c:3087 pcpu_get_vm_areas+0x488/0x838 and the system cannot boot successfully. Let's implement page mapping percpu first chunk allocator as a fallback to the embedding allocator to increase the robustness of the system. Also fix a crash when both NEED_PER_CPU_PAGE_FIRST_CHUNK and KASAN_VMALLOC enabled. Tested on ARM64 qemu with cmdline "percpu_alloc=page". This patch (of 3): There are some fixed locations in the vmalloc area be reserved in ARM(see iotable_init()) and ARM64(see map_kernel()), but for pcpu_page_first_chunk(), it calls vm_area_register_early() and choose VMALLOC_START as the start address of vmap area which could be conflicted with above address, then could trigger a BUG_ON in vm_area_add_early(). Let's choose a suit start address by traversing the vmlist. Link: https://lkml.kernel.org/r/20210910053354.26721-1-wangkefeng.wang@huawei.com Link: https://lkml.kernel.org/r/20210910053354.26721-2-wangkefeng.wang@huawei.comSigned-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Marco Elver <elver@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Vasily Averin authored
Huge vmalloc allocation on heavy loaded node can lead to a global memory shortage. Task called vmalloc can have worst badness and be selected by OOM-killer, however taken fatal signal does not interrupt allocation cycle. Vmalloc repeat page allocaions again and again, exacerbating the crisis and consuming the memory freed up by another killed tasks. After a successful completion of the allocation procedure, a fatal signal will be processed and task will be destroyed finally. However it may not release the consumed memory, since the allocated object may have a lifetime unrelated to the completed task. In the worst case, this can lead to the host will panic due to "Out of memory and no killable processes..." This patch allows OOM-killer to break vmalloc cycle, makes OOM more effective and avoid host panic. It does not check oom condition directly, however, and breaks page allocation cycle when fatal signal was received. This may trigger some hidden problems, when caller does not handle vmalloc failures, or when rollaback after failed vmalloc calls own vmallocs inside. However all of these scenarios are incorrect: vmalloc does not guarantee successful allocation, it has never been called with __GFP_NOFAIL and threfore either should not be used for any rollbacks or should handle such errors correctly and not lead to critical failures. Link: https://lkml.kernel.org/r/83efc664-3a65-2adb-d7c4-2885784cf109@virtuozzo.comSigned-off-by: Vasily Averin <vvs@virtuozzo.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Uladzislau Rezki (Sony) authored
Before we did not guarantee a free block with lowest start address for allocations with alignment >= PAGE_SIZE. Because an alignment overhead was included into a search length like below: length = size + align - 1; doing so we make sure that a bigger block would fit after applying an alignment adjustment. Now there is no such limitation, i.e. any alignment that user wants to apply will result to a lowest address of returned free area. Link: https://lkml.kernel.org/r/20211004142829.22222-2-urezki@gmail.comSigned-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Hocko <mhocko@suse.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: Ping Fang <pifang@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Uladzislau Rezki (Sony) authored
We used to include an alignment overhead into a search length, in that case we guarantee that a found area will definitely fit after applying a specific alignment that user specifies. From the other hand we do not guarantee that an area has the lowest address if an alignment is >= PAGE_SIZE. It means that, when a user specifies a special alignment together with a range that corresponds to an exact requested size then an allocation will fail. This is what happens to KASAN, it wants the free block that exactly matches a specified range during onlining memory banks: [root@vm-0 fedora]# echo online > /sys/devices/system/memory/memory82/state [root@vm-0 fedora]# echo online > /sys/devices/system/memory/memory83/state [root@vm-0 fedora]# echo online > /sys/devices/system/memory/memory85/state [root@vm-0 fedora]# echo online > /sys/devices/system/memory/memory84/state vmap allocation for size 16777216 failed: use vmalloc=<size> to increase size bash: vmalloc: allocation failure: 16777216 bytes, mode:0x6000c0(GFP_KERNEL), nodemask=(null),cpuset=/,mems_allowed=0 CPU: 4 PID: 1644 Comm: bash Kdump: loaded Not tainted 4.18.0-339.el8.x86_64+debug #1 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 Call Trace: dump_stack+0x8e/0xd0 warn_alloc.cold.90+0x8a/0x1b2 ? zone_watermark_ok_safe+0x300/0x300 ? slab_free_freelist_hook+0x85/0x1a0 ? __get_vm_area_node+0x240/0x2c0 ? kfree+0xdd/0x570 ? kmem_cache_alloc_node_trace+0x157/0x230 ? notifier_call_chain+0x90/0x160 __vmalloc_node_range+0x465/0x840 ? mark_held_locks+0xb7/0x120 Fix it by making sure that find_vmap_lowest_match() returns lowest start address with any given alignment value, i.e. for alignments bigger then PAGE_SIZE the algorithm rolls back toward parent nodes checking right sub-trees if the most left free block did not fit due to alignment overhead. Link: https://lkml.kernel.org/r/20211004142829.22222-1-urezki@gmail.com Fixes: 68ad4a33 ("mm/vmalloc.c: keep track of free blocks for vmap allocation") Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Reported-by: Ping Fang <pifang@redhat.com> Tested-by: David Hildenbrand <david@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Christoph Hellwig <hch@infradead.org> Cc: Matthew Wilcox <willy@infradead.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Hillf Danton <hdanton@sina.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sonymobile.com> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Eric Dumazet authored
If last va found in vmap_area_list does not have a vm pointer, vmallocinfo.s_show() returns 0, and show_purge_info() is not called as it should. Link: https://lkml.kernel.org/r/20211001170815.73321-1-eric.dumazet@gmail.com Fixes: dd3b8353 ("mm/vmalloc: do not keep unpurged areas in the busy tree") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Pengfei Li <lpf.vector@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Eric Dumazet authored
show_numa_info() can be slightly faster, by skipping over hugepages directly. Link: https://lkml.kernel.org/r/20211001172725.105824-1-eric.dumazet@gmail.comSigned-off-by: Eric Dumazet <edumazet@google.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Peter Zijlstra authored
The vmalloc guard pages are added on top of each allocation, thereby isolating any two allocations from one another. The top guard of the lower allocation is the bottom guard guard of the higher allocation etc. Therefore VM_NO_GUARD is dangerous; it breaks the basic premise of isolating separate allocations. There are only two in-tree users of this flag, neither of which use it through the exported interface. Ensure it stays this way. Link: https://lkml.kernel.org/r/YUMfdA36fuyZ+/xt@hirez.programming.kicks-ass.netSigned-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Will Deacon <will@kernel.org> Acked-by: Kees Cook <keescook@chromium.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Uladzislau Rezki <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Vasily Averin authored
Commit f255935b ("mm: cleanup the gfp_mask handling in __vmalloc_area_node") added __GFP_NOWARN to gfp_mask unconditionally however it disabled all output inside warn_alloc() call. This patch saves original gfp_mask and provides it to all warn_alloc() calls. Link: https://lkml.kernel.org/r/f4f3187b-9684-e426-565d-827c2a9bbb0e@virtuozzo.com Fixes: f255935b ("mm: cleanup the gfp_mask handling in __vmalloc_area_node") Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Gang Li authored
By using DECLARE_EVENT_CLASS and TRACE_EVENT_FN, we can save a lot of space from duplicate code. Link: https://lkml.kernel.org/r/20211009071243.70286-1-ligang.bdlg@bytedance.comSigned-off-by: Gang Li <ligang.bdlg@bytedance.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Gang Li authored
Ftrace core will add newline automatically on printing, so using it in TP_printkcreates a blank line. Link: https://lkml.kernel.org/r/20211009071105.69544-1-ligang.bdlg@bytedance.comSigned-off-by: Gang Li <ligang.bdlg@bytedance.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Lucas De Marchi authored
The fallback was introduced in commit 80c33624 ("io-mapping: Fixup for different names of writecombine") to fix the build on microblaze. 5 years later, it seems all archs now provide a pgprot_writecombine(), so just remove the other possible fallbacks. For microblaze, pgprot_writecombine() is available since commit 97ccedd7 ("microblaze: Provide pgprot_device/writecombine macros for nommu"). This is build-tested on microblaze with a hack to always build mm/io-mapping.o and without DIYing on an x86-only macro (_PAGE_CACHE_MASK) Link: https://lkml.kernel.org/r/20211020204838.1142908-1-lucas.demarchi@intel.comSigned-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Cc: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Dmitry Safonov authored
All this vm_unacct_memory(charged) dance seems to complicate the life without a good reason. Furthermore, it seems not always done right on error-pathes in mremap_to(). And worse than that: this `charged' difference is sometimes double-accounted for growing MREMAP_DONTUNMAP mremap()s in move_vma(): if (security_vm_enough_memory_mm(mm, new_len >> PAGE_SHIFT)) Let's not do this. Account memory in mremap() fast-path for growing VMAs or in move_vma() for actually moving things. The same simpler way as it's done by vm_stat_account(), but with a difference to call security_vm_enough_memory_mm() before copying/adjusting VMA. Originally noticed by Chen Wandun: https://lkml.kernel.org/r/20210717101942.120607-1-chenwandun@huawei.com Link: https://lkml.kernel.org/r/20210721131320.522061-1-dima@arista.com Fixes: e346b381 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()") Signed-off-by: Dmitry Safonov <dima@arista.com> Acked-by: Brian Geffon <bgeffon@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Andy Lutomirski <luto@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chen Wandun <chenwandun@huawei.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Dave Jiang <dave.jiang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vishal Verma <vishal.l.verma@intel.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Wei Yongjun <weiyongjun1@huawei.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Liu Song authored
After adjustment, the repeated assignment of "prev" is avoided, and the readability of the code is improved. Link: https://lkml.kernel.org/r/20211012152444.4127-1-fishland@aliyun.comReviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Liu Song <liu.song11@zte.com.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Lukas Bulwahn authored
Commit 3947be19 ("[PATCH] memory hotplug: sysfs and add/remove functions") defines CONFIG_MEM_BLOCK_SIZE, but this has never been utilized anywhere. It is a good practice to keep the CONFIG_* defines exclusively for the Kbuild system. So, drop this unused definition. This issue was noticed due to running ./scripts/checkkconfigsymbols.py. Link: https://lkml.kernel.org/r/20211006120354.7468-1-lukas.bulwahn@gmail.comSigned-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Tiberiu A Georgescu authored
This patch follows the discussions on previous documentation patch threads [1][2]. It presents the exception case of shared memory management from the pagemap's point of view. It briefly describes what is missing, why it is missing and alternatives to the pagemap for page info retrieval in user space. In short, the kernel does not keep track of PTEs for swapped out shared pages within the processes that references them. Thus, the proc/pid/pagemap tool cannot print the swap destination of the shared memory pages, instead setting the pagemap entry to zero for both non-allocated and swapped out pages. This can create confusion for users who need information on swapped out pages. The reasons why maintaining the PTEs of all swapped out shared pages among all processes while maintaining similar performance is not a trivial task, or a desirable change, have been discussed extensively [1][3][4][5]. There are also arguments for why this arguably missing information should eventually be exposed to the user in either a future pagemap patch, or by an alternative tool. [1]: https://marc.info/?m=162878395426774 [2]: https://lore.kernel.org/lkml/20210920164931.175411-1-tiberiu.georgescu@nutanix.com/ [3]: https://lore.kernel.org/lkml/20210730160826.63785-1-tiberiu.georgescu@nutanix.com/ [4]: https://lore.kernel.org/lkml/20210807032521.7591-1-peterx@redhat.com/ [5]: https://lore.kernel.org/lkml/20210715201651.212134-1-peterx@redhat.com/ Mention the current missing information in the pagemap and alternatives on how to retrieve it, in case someone stumbles upon unexpected behaviour. Link: https://lkml.kernel.org/r/20210923064618.157046-1-tiberiu.georgescu@nutanix.com Link: https://lkml.kernel.org/r/20210923064618.157046-2-tiberiu.georgescu@nutanix.comSigned-off-by: Tiberiu A Georgescu <tiberiu.georgescu@nutanix.com> Reviewed-by: Ivan Teterevkov <ivan.teterevkov@nutanix.com> Reviewed-by: Florian Schmidt <florian.schmidt@nutanix.com> Reviewed-by: Carl Waldspurger <carl.waldspurger@nutanix.com> Reviewed-by: Jonathan Davies <jonathan.davies@nutanix.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Qi Zheng authored
The smp_wmb() which is in the __pte_alloc() is used to ensure all ptes setup is visible before the pte is made visible to other CPUs by being put into page tables. We only need this when the pte is actually populated, so move it to pmd_install(). __pte_alloc_kernel(), __p4d_alloc(), __pud_alloc() and __pmd_alloc() are similar to this case. We can also defer smp_wmb() to the place where the pmd entry is really populated by preallocated pte. There are two kinds of user of preallocated pte, one is filemap & finish_fault(), another is THP. The former does not need another smp_wmb() because the smp_wmb() has been done by pmd_install(). Fortunately, the latter also does not need another smp_wmb() because there is already a smp_wmb() before populating the new pte when the THP uses a preallocated pte to split a huge pmd. Link: https://lkml.kernel.org/r/20210901102722.47686-3-zhengqi.arch@bytedance.comSigned-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Acked-by: David Hildenbrand <david@redhat.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mika Penttila <mika.penttila@nextfour.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Qi Zheng authored
Patch series "Do some code cleanups related to mm", v3. This patch (of 2): Currently we have three times the same few lines repeated in the code. Deduplicate them by newly introduced pmd_install() helper. Link: https://lkml.kernel.org/r/20210901102722.47686-1-zhengqi.arch@bytedance.com Link: https://lkml.kernel.org/r/20210901102722.47686-2-zhengqi.arch@bytedance.comSigned-off-by: Qi Zheng <zhengqi.arch@bytedance.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Vladimir Davydov <vdavydov.dev@gmail.com> Cc: Mika Penttila <mika.penttila@nextfour.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-
Peter Xu authored
Use the helper for the checks. Rename "check_mapping" into "zap_mapping" because "check_mapping" looks like a bool but in fact it stores the mapping itself. When it's set, we check the mapping (it must be non-NULL). When it's cleared we skip the check, which works like the old way. Move the duplicated comments to the helper too. Link: https://lkml.kernel.org/r/20210915181538.11288-1-peterx@redhat.comSigned-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Alistair Popple <apopple@nvidia.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jerome Glisse <jglisse@redhat.com> Cc: "Kirill A . Shutemov" <kirill@shutemov.name> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Rapoport <rppt@linux.vnet.ibm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-