- 02 Sep, 2024 33 commits
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David Hildenbrand authored
Patch series "mm: split PTE/PMD PT table Kconfig cleanups+clarifications". This series is a follow up to the fixes: "[PATCH v1 0/2] mm/hugetlb: fix hugetlb vs. core-mm PT locking" When working on the fixes, I wondered why 8xx is fine (-> never uses split PT locks) and how PT locking even works properly with PMD page table sharing (-> always requires split PMD PT locks). Let's improve the split PT lock detection, make hugetlb properly depend on it and make 8xx bail out if it would ever get enabled by accident. As an alternative to patch #3 we could extend the Kconfig SPLIT_PTE_PTLOCKS option from patch #2 -- but enforcing it closer to the code that actually implements it feels a bit nicer for documentation purposes, and there is no need to actually disable it because it should always be disabled (!SMP). Did a bunch of cross-compilations to make sure that split PTE/PMD PT locks are still getting used where we would expect them. [1] https://lkml.kernel.org/r/20240725183955.2268884-1-david@redhat.com This patch (of 3): Let's clean that up a bit and prepare for depending on CONFIG_SPLIT_PMD_PTLOCKS in other Kconfig options. More cleanups would be reasonable (like the arch-specific "depends on" for CONFIG_SPLIT_PTE_PTLOCKS), but we'll leave that for another day. Link: https://lkml.kernel.org/r/20240726150728.3159964-1-david@redhat.com Link: https://lkml.kernel.org/r/20240726150728.3159964-2-david@redhat.comSigned-off-by:
David Hildenbrand <david@redhat.com> Acked-by:
Mike Rapoport (Microsoft) <rppt@kernel.org> Reviewed-by:
Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Reviewed-by:
Qi Zheng <zhengqi.arch@bytedance.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Borislav Petkov <bp@alien8.de> Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Juergen Gross <jgross@suse.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Peter Xu <peterx@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by:
Andrew Morton <akpm@linux-foundation.org>
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Roman Gushchin authored
When a page_counter structure is initialized, there is no need to use an atomic set operation to initialize the usage counter because at this point the structure is not visible to anybody else. ATOMIC_LONG_INIT() is what should be used in such cases. Link: https://lkml.kernel.org/r/20240726203110.1577216-4-roman.gushchin@linux.devSigned-off-by:
Roman Gushchin <roman.gushchin@linux.dev> Acked-by:
Shakeel Butt <shakeel.butt@linux.dev> Acked-by:
Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by:
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Roman Gushchin authored
Put page_counter_calculate_protection() under CONFIG_MEMCG. The protection functionality (min/low limits) is not supported by any other cgroup subsystem, so page_counter_calculate_protection() and related static effective_protection() can be compiled out if CONFIG_MEMCG is not enabled. Link: https://lkml.kernel.org/r/20240726203110.1577216-3-roman.gushchin@linux.devSigned-off-by:
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Roman Gushchin authored
Patch series "mm: memcg: page counters optimizations", v3. This patchset contains 3 independent small optimizations of page counters. This patch (of 3): Memory protection (min/low) requires a constant tracking of protected memory usage. propagate_protected_usage() is called on each page counters update and does a number of operations even in cases when the actual memory protection functionality is not supported (e.g. hugetlb cgroups or memcg swap counters). It's obviously inefficient and leads to a waste of CPU cycles. It can be addressed by calling propagate_protected_usage() only for the counters which do support memory guarantees. As of now it's only memcg->memory - the unified memory memcg counter. Link: https://lkml.kernel.org/r/20240726203110.1577216-2-roman.gushchin@linux.devSigned-off-by:
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Kefeng Wang authored
The comment is useless after commit 57a196a5 ("hugetlb: simplify hugetlb handling in follow_page_mask") since all follow_huge_foo() are killed. Link: https://lkml.kernel.org/r/20240725021643.1358536-1-wangkefeng.wang@huawei.comSigned-off-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Reviewed-by:
Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by:
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Pavel Tikhomirov authored
Add a per-CPU memory leak, which will be reported like: unreferenced object 0x3efa840195f8 (size 64): comm "modprobe", pid 4667, jiffies 4294688677 hex dump (first 32 bytes on cpu 0): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace (crc 0): [<ffffffffa7fa87af>] pcpu_alloc+0x3df/0x840 [<ffffffffc11642d9>] kmemleak_test_init+0x2c9/0x2f0 [kmemleak_test] [<ffffffffa7c02264>] do_one_initcall+0x44/0x300 [<ffffffffa7de9e10>] do_init_module+0x60/0x240 [<ffffffffa7deb946>] init_module_from_file+0x86/0xc0 [<ffffffffa7deba99>] idempotent_init_module+0x109/0x2a0 [<ffffffffa7debd2a>] __x64_sys_finit_module+0x5a/0xb0 [<ffffffffa88f4f3a>] do_syscall_64+0x7a/0x160 [<ffffffffa8a0012b>] entry_SYSCALL_64_after_hwframe+0x76/0x7e Link: https://lkml.kernel.org/r/20240725041223.872472-3-ptikhomirov@virtuozzo.comSigned-off-by:Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Acked-by:
Catalin Marinas <catalin.marinas@arm.com> Cc: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Cc: Chen Jun <chenjun102@huawei.com> Cc: Wei Yongjun <weiyongjun1@huawei.com> Signed-off-by:
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Pavel Tikhomirov authored
Patch series "kmemleak: support for percpu memory leak detect'. This is a rework of this series: https://lore.kernel.org/lkml/20200921020007.35803-1-chenjun102@huawei.com/ Originally I was investigating a percpu leak on our customer nodes and having this functionality was a huge help, which lead to this fix [1]. So probably it's a good idea to have it in mainstream too, especially as after [2] it became much easier to implement (we already have a separate tree for percpu pointers). [1] commit 0af8c09c ("netfilter: x_tables: fix percpu counter block leak on error path when creating new netns") [2] commit 39042079 ("kmemleak: avoid RCU stalls when freeing metadata for per-CPU pointers") This patch (of 2): This basically does: - Add min_percpu_addr and max_percpu_addr to filter out unrelated data similar to min_addr and max_addr; - Set min_count for percpu pointers to 1 to start tracking them; - Calculate checksum of percpu area as xor of crc32 for each cpu; - Split pointer lookup and update refs code into separate helper and use it twice: once as if the pointer is a virtual pointer and once as if it's percpu. [ptikhomirov@virtuozzo.com: v2] Link: https://lkml.kernel.org/r/20240731025526.157529-2-ptikhomirov@virtuozzo.com Link: https://lkml.kernel.org/r/20240725041223.872472-1-ptikhomirov@virtuozzo.com Link: https://lkml.kernel.org/r/20240725041223.872472-2-ptikhomirov@virtuozzo.comSigned-off-by:
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Pasha Tatashin authored
Given that stack_not_used() is not performance critical function uninline it. Link: https://lkml.kernel.org/r/20240730150158.832783-4-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-4-pasha.tatashin@soleen.comSigned-off-by:
Pasha Tatashin <pasha.tatashin@soleen.com> Acked-by:
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Pasha Tatashin authored
As part of the dynamic kernel stack project, we need to know the amount of data that can be saved by reducing the default kernel stack size [1]. Provide a kernel stack usage histogram to aid in optimizing kernel stack sizes and minimizing memory waste in large-scale environments. The histogram divides stack usage into power-of-two buckets and reports the results in /proc/vmstat. This information is especially valuable in environments with millions of machines, where even small optimizations can have a significant impact. The histogram data is presented in /proc/vmstat with entries like "kstack_1k", "kstack_2k", and so on, indicating the number of threads that exited with stack usage falling within each respective bucket. Example outputs: Intel: $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 ARM with 64K page_size: $ grep kstack /proc/vmstat kstack_1k 1 kstack_2k 340 kstack_4k 25212 kstack_8k 1659 kstack_16k 0 kstack_32k 0 kstack_64k 0 Note: once the dynamic kernel stack is implemented it will depend on the implementation the usability of this feature: On hardware that supports faults on kernel stacks, we will have other metrics that show the total number of pages allocated for stacks. On hardware where faults are not supported, we will most likely have some optimization where only some threads are extended, and for those, these metrics will still be very useful. [1] https://lwn.net/Articles/974367 Link: https://lkml.kernel.org/r/20240730150158.832783-3-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-3-pasha.tatashin@soleen.comSigned-off-by:
Kent Overstreet <kent.overstreet@linux.dev> Acked-by:
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Shakeel Butt authored
Patch series "Kernel stack usage histogram", v6. Provide histogram of stack sizes for the exited threads: Example outputs: Intel: $ grep kstack /proc/vmstat kstack_1k 3 kstack_2k 188 kstack_4k 11391 kstack_8k 243 kstack_16k 0 ARM with 64K page_size: $ grep kstack /proc/vmstat kstack_1k 1 kstack_2k 340 kstack_4k 25212 kstack_8k 1659 kstack_16k 0 kstack_32k 0 kstack_64k 0 This patch (of 3): At the moment the valid index for the indirection tables for memcg stats and events is < S8_MAX. These indirection tables are used in performance critical codepaths. With the latest addition to the vm_events, the NR_VM_EVENT_ITEMS has gone over S8_MAX. One way to resolve is to increase the entry size of the indirection table from int8_t to int16_t but this will increase the potential number of cachelines needed to access the indirection table. This patch took a different approach and make the valid index < U8_MAX. In this way the size of the indirection tables will remain same and we only need to invalid index check from less than 0 to equal to U8_MAX. In this approach we have also removed a subtraction from the performance critical codepaths. [pasha.tatashin@soleen.com: v6] Link: https://lkml.kernel.org/r/20240730150158.832783-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-1-pasha.tatashin@soleen.com Link: https://lkml.kernel.org/r/20240724203322.2765486-2-pasha.tatashin@soleen.comSigned-off-by:
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Zhiguo Jiang authored
The releasing process of the non-shared anonymous folio mapped solely by an exiting process may go through two flows: 1) the anonymous folio is firstly is swaped-out into swapspace and transformed into a swp_entry in shrink_folio_list; 2) then the swp_entry is released in the process exiting flow. This will result in the high cpu load of releasing a non-shared anonymous folio mapped solely by an exiting process. When the low system memory and the exiting process exist at the same time, it will be likely to happen, because the non-shared anonymous folio mapped solely by an exiting process may be reclaimed by shrink_folio_list. This patch is that shrink skips the non-shared anonymous folio solely mapped by an exting process and this folio is only released directly in the process exiting flow, which will save swap-out time and alleviate the load of the process exiting. Barry provided some effectiveness testing in [1]. "I observed that this patch effectively skipped 6114 folios (either 4KB or 64KB mTHP), potentially reducing the swap-out by up to 92MB (97,300,480 bytes) during the process exit. The working set size is 256MB." Link: https://lkml.kernel.org/r/20240710083641.546-1-justinjiang@vivo.com Link: https://lore.kernel.org/linux-mm/20240710033212.36497-1-21cnbao@gmail.com/ [1] Signed-off-by:
Zhiguo Jiang <justinjiang@vivo.com> Acked-by:
Barry Song <baohua@kernel.org> Cc: David Hildenbrand <david@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Signed-off-by:
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Yu Zhao authored
Remove boilerplate by using a macro to choose the corresponding lock and handler for each folio_batch in cpu_fbatches. [yuzhao@google.com: handle zero-length local_lock_t] Link: https://lkml.kernel.org/r/Zq_0X04WsqgUnz30@google.com [yuzhao@google.com: fix "BUG: using smp_processor_id() in preemptible"] Link: https://lkml.kernel.org/r/ZqNHHMiHn-9vy_II@google.com Link: https://lkml.kernel.org/r/20240711021317.596178-6-yuzhao@google.comSigned-off-by:
Yu Zhao <yuzhao@google.com> Tested-by:
Hugh Dickins <hughd@google.com> Cc: Barry Song <21cnbao@gmail.com> Signed-off-by:
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Yu Zhao authored
Remove remaining _fn suffix from cpu_fbatches handlers, which are already self-explanatory. Link: https://lkml.kernel.org/r/20240711021317.596178-5-yuzhao@google.comSigned-off-by:
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Yu Zhao authored
Fold lru_rotate into cpu_fbatches, and rename the folio_batch and the lock protecting it to lru_move_tail and lock_irq respectively so that all the boilerplate can be removed at the end of this series. Also remove data_race() around folio_batch_count(), which is out of place: all folio_batch_count() calls on remote cpu_fbatches are subject to data_race(), and therefore data_race() should be inside folio_batch_count(). Link: https://lkml.kernel.org/r/20240711021317.596178-4-yuzhao@google.comSigned-off-by:
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Yu Zhao authored
Rename cpu_fbatches->activate to cpu_fbatches->lru_activate, and its handler folio_activate_fn() to lru_activate() so that all the boilerplate can be removed at the end of this series. Link: https://lkml.kernel.org/r/20240711021317.596178-3-yuzhao@google.comSigned-off-by:
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Yu Zhao authored
Patch series "mm/swap: remove boilerplate". This patch (of 5): Use folio_activate() as an example: Before this series ------------------ if (!folio_test_active(folio) && !folio_test_unevictable(folio)) { struct folio_batch *fbatch; folio_get(folio); if (!folio_test_clear_lru(folio)) { folio_put(folio); return; } local_lock(&cpu_fbatches.lock); fbatch = this_cpu_ptr(&cpu_fbatches.activate); folio_batch_add_and_move(fbatch, folio, folio_activate_fn); local_unlock(&cpu_fbatches.lock); } } After this series ----------------- void folio_activate(struct folio *folio) { if (folio_test_active(folio) || folio_test_unevictable(folio)) return; folio_batch_add_and_move(folio, lru_activate, true); } And this is applied to all 6 folio_batch handlers in mm/swap.c. bloat-o-meter ------------- add/remove: 12/13 grow/shrink: 3/2 up/down: 4653/-4721 (-68) ... Total: Before=28083019, After=28082951, chg -0.00% This patch (of 5): Reduce indentation level by returning directly when there is no cleanup needed, i.e., if (condition) { | if (condition) { do_this(); | do_this(); return; | return; } else { | } do_that(); | } | do_that(); and if (condition) { | if (!condition) do_this(); | return; do_that(); | } | do_this(); return; | do_that(); Presumably the old style became repetitive as the result of copy and paste. Link: https://lkml.kernel.org/r/20240711021317.596178-1-yuzhao@google.com Link: https://lkml.kernel.org/r/20240711021317.596178-2-yuzhao@google.comSigned-off-by: -
Zi Yan authored
memory tiering can be enabled/disabled at runtime and sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING is used to check it. In migrate_misplaced_folio(), the check is missing when PGPROMOTE_SUCCESS is incremented. Add the missing check. Link: https://lkml.kernel.org/r/20240724130115.793641-4-ziy@nvidia.com Fixes: 33024536 ("memory tiering: hot page selection with hint page fault latency") Reported-by:
Zi Yan <ziy@nvidia.com> Acked-by:
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Zi Yan authored
If memory tiering mode is on and a folio is not in the top tier memory, folio's cpupid field is repurposed to store page access time. Instead of an open coded check, use a function to encapsulate the check. Link: https://lkml.kernel.org/r/20240724130115.793641-3-ziy@nvidia.comSigned-off-by:
"Huang, Ying" <ying.huang@intel.com> Acked-by:
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Zi Yan authored
Patch series "Various memory tiering fixes", v3. This patch (of 3): last_cpupid is only available when memory tiering is off or the folio is in toptier node. Complete the check to read last_cpupid when it is available. Before the fix, the default last_cpupid will be used even if memory tiering mode is turned off at runtime instead of the actual value. This can prevent task_numa_fault() from getting right numa fault stats, but should not cause any crash. User might see performance changes after the fix. Link: https://lkml.kernel.org/r/20240724130115.793641-1-ziy@nvidia.com Link: https://lkml.kernel.org/r/20240724130115.793641-2-ziy@nvidia.com Fixes: 33024536 ("memory tiering: hot page selection with hint page fault latency") Signed-off-by:
Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by:
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Barry Song authored
Extend a usage parameter so that cluster_swap_free_nr() can be reused by both swapcache_clear() and swap_free(). __swap_entry_free() is quite similar but more tricky as it requires the return value of __swap_entry_free_locked() which cluster_swap_free_nr() doesn't support. Link: https://lkml.kernel.org/r/20240724020056.65838-1-21cnbao@gmail.comSigned-off-by:
Barry Song <v-songbaohua@oppo.com> Reviewed-by:
Ryan Roberts <ryan.roberts@arm.com> Acked-by:
Chris Li <chrisl@kernel.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kairui Song <kasong@tencent.com> Cc: David Hildenbrand <david@redhat.com> Cc: Chuanhua Han <hanchuanhua@oppo.com> Signed-off-by:
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Muchun Song authored
There is no user of mem_cgroup_from_obj(), remove it. Link: https://lkml.kernel.org/r/20240718091821.44740-1-songmuchun@bytedance.comSigned-off-by:
Muchun Song <songmuchun@bytedance.com> Acked-by:
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Josef Bacik authored
Now that we're not passing around a pointer to the flags, there's no reason to have an extra variable for the gup_flags, simply pass the gup_flags directly everywhere. Link: https://lkml.kernel.org/r/1e79b84bd30287cc9847f2aeb002374e6e60a10f.1721337845.git.josef@toxicpanda.comSigned-off-by:
Josef Bacik <josef@toxicpanda.com> Acked-by:
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Josef Bacik authored
Patch series "mm: some small page fault cleanups". I was recently wreaking havoc in the page fault code and I noticed some things that could be cleaned up. We no longer modify the gup flags in faultin_page, so we can clean up how we pass the flags in and remove the extra variable in __get_user_pages. This patch (of 2): We're passing a pointer to the foll_flags for faultin_page, however we never modify the flags in this call. Change this to just take the flags value instead. Link: https://lkml.kernel.org/r/2df51a54c06bdf93e1cb09a19a9ef1df6557b59e.1721337845.git.josef@toxicpanda.comSigned-off-by:
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Peng Hao authored
When KASAN is enabled and built with clang: mm/damon/lru_sort.c:199:12: error: stack frame size (2328) exceeds limit (2048) in 'damon_lru_sort_apply_parameters' [-Werror,-Wframe-larger-than] static int damon_lru_sort_apply_parameters(void) ^ 1 error generated. This is because damon_lru_sort_quota contains a large array, and assigning this variable to a local variable causes a large amount of stack space to be occupied. So adjust local variable to dynamic allocation. Link: https://lkml.kernel.org/r/20240723035513.20153-1-flyingpeng@tencent.comSigned-off-by:Peng Hao <flyingpeng@tencent.com> Reviewed-by:
SeongJae Park <sj@kernel.org> Signed-off-by:
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Yu Zhao authored
hugetlb_vmemmap_optimize_folio() and hugetlb_vmemmap_restore_folio() are wrappers meant to be called regardless of whether HVO is enabled. Therefore, they should not call synchronize_rcu(). Otherwise, it regresses use cases not enabling HVO. So move synchronize_rcu() to __hugetlb_vmemmap_optimize_folio() and __hugetlb_vmemmap_restore_folio(), and call it once for each batch of folios when HVO is enabled. Link: https://lkml.kernel.org/r/20240719042503.2752316-1-yuzhao@google.com Fixes: bd225530 ("mm/hugetlb_vmemmap: fix race with speculative PFN walkers") Signed-off-by:
kernel test robot <oliver.sang@intel.com> Closes: https://lore.kernel.org/oe-lkp/202407091001.1250ad4a-oliver.sang@intel.comReported-by:
Janosch Frank <frankja@linux.ibm.com> Tested-by:
Marc Hartmayer <mhartmay@linux.ibm.com> Acked-by:
Muchun Song <muchun.song@linux.dev> Signed-off-by:
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Carlos Maiolino authored
Initially I added shmem-quota to obj-y, move it to the correct place and remove the unneeded full file #ifdef Link: https://lkml.kernel.org/r/20240717063737.910840-1-cem@kernel.orgSigned-off-by:
Carlos Maiolino <cmaiolino@redhat.com> Suggested-by:
Aristeu Rozanski <aris@redhat.com> Reviewed-by:
Jan Kara <jack@suse.cz> Cc: Christian Brauner <brauner@kernel.org> Cc: Hugh Dickins <hughd@google.com> Signed-off-by:
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Valdis Kletnieks authored
Fix typo in Kconfig help Link: https://lkml.kernel.org/r/78656.1720853990@turing-police Fixes: e93d4166 ("mm: memcg: put cgroup v1-specific code under a config option") Signed-off-by:
Valdis Kletnieks <valdis.kletnieks@vt.edu> Acked-by:
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Baolin Wang authored
Move shmem_huge_global_enabled() into shmem_allowable_huge_orders(), so that shmem_allowable_huge_orders() can also help to find the allowable huge orders for tmpfs. Moreover the shmem_huge_global_enabled() can become static. While we are at it, passing the vma instead of mm for shmem_huge_global_enabled() makes code cleaner. No functional changes. Link: https://lkml.kernel.org/r/8e825146bb29ee1a1c7bd64d2968ff3e19be7815.1721626645.git.baolin.wang@linux.alibaba.comSigned-off-by:
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Baolin Wang authored
shmem_is_huge() is now used to check if the top-level huge page is enabled, thus rename it to reflect its usage. Link: https://lkml.kernel.org/r/da53296e0ab6359aa083561d9dc01e4223d60fbe.1721626645.git.baolin.wang@linux.alibaba.comSigned-off-by:
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Baolin Wang authored
Patch series "Some cleanups for shmem", v3. This series does some cleanups to reuse code, rename functions and simplify logic to make code more clear. No functional changes are expected. This patch (of 3): Move the suitable huge orders validation into shmem_suitable_orders() for tmpfs, which can reuse some code to simplify the logic. In addition, we don't have special handling for the error code -E2BIG when checking for conflicts with PMD sized THP in the pagecache for tmpfs, instead, it will just fallback to order-0 allocations like this patch does, so this simplification will not add functional changes. Link: https://lkml.kernel.org/r/cover.1721626645.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/965985dd6d322929d78a0beee0dafa1c2a1b81e2.1721626645.git.baolin.wang@linux.alibaba.comSigned-off-by:
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Danilo Krummrich authored
Besides the obvious (and desired) difference between krealloc() and kvrealloc(), there is some inconsistency in their function signatures and behavior: - krealloc() frees the memory when the requested size is zero, whereas kvrealloc() simply returns a pointer to the existing allocation. - krealloc() behaves like kmalloc() if a NULL pointer is passed, whereas kvrealloc() does not accept a NULL pointer at all and, if passed, would fault instead. - krealloc() is self-contained, whereas kvrealloc() relies on the caller to provide the size of the previous allocation. Inconsistent behavior throughout allocation APIs is error prone, hence make kvrealloc() behave like krealloc(), which seems superior in all mentioned aspects. Besides that, implementing kvrealloc() by making use of krealloc() and vrealloc() provides oppertunities to grow (and shrink) allocations more efficiently. For instance, vrealloc() can be optimized to allocate and map additional pages to grow the allocation or unmap and free unused pages to shrink the allocation. [dakr@kernel.org: document concurrency restrictions] Link: https://lkml.kernel.org/r/20240725125442.4957-1-dakr@kernel.org [dakr@kernel.org: disable KASAN when switching to vmalloc] Link: https://lkml.kernel.org/r/20240730185049.6244-2-dakr@kernel.org [dakr@kernel.org: properly document __GFP_ZERO behavior] Link: https://lkml.kernel.org/r/20240730185049.6244-5-dakr@kernel.org Link: https://lkml.kernel.org/r/20240722163111.4766-3-dakr@kernel.orgSigned-off-by:
Danilo Krummrich <dakr@kernel.org> Acked-by:
Michal Hocko <mhocko@suse.com> Acked-by:
Vlastimil Babka <vbabka@suse.cz> Cc: Chandan Babu R <chandan.babu@oracle.com> Cc: Christian König <christian.koenig@amd.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <kees@kernel.org> Cc: Marc Zyngier <maz@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Oliver Upton <oliver.upton@linux.dev> Cc: Pekka Enberg <penberg@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Uladzislau Rezki <urezki@gmail.com> Cc: Wedson Almeida Filho <wedsonaf@gmail.com> Signed-off-by:
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Danilo Krummrich authored
Patch series "Align kvrealloc() with krealloc()", v2. Besides the obvious (and desired) difference between krealloc() and kvrealloc(), there is some inconsistency in their function signatures and behavior: - krealloc() frees the memory when the requested size is zero, whereas kvrealloc() simply returns a pointer to the existing allocation. - krealloc() behaves like kmalloc() if a NULL pointer is passed, whereas kvrealloc() does not accept a NULL pointer at all and, if passed, would fault instead. - krealloc() is self-contained, whereas kvrealloc() relies on the caller to provide the size of the previous allocation. Inconsistent behavior throughout allocation APIs is error prone, hence make kvrealloc() behave like krealloc(), which seems superior in all mentioned aspects. In order to be able to get rid of kvrealloc()'s oldsize parameter, introduce vrealloc() and make use of it in kvrealloc(). Making use of vrealloc() in kvrealloc() also provides oppertunities to grow (and shrink) allocations more efficiently. For instance, vrealloc() can be optimized to allocate and map additional pages to grow the allocation or unmap and free unused pages to shrink the allocation. Besides the above, those functions are required by Rust's allocator abstractons [1] (rework based on this series in [2]). With `Vec` or `KVec` respectively, potentially growing (and shrinking) data structures are rather common. [1] https://lore.kernel.org/lkml/20240704170738.3621-1-dakr@redhat.com/ [2] https://git.kernel.org/pub/scm/linux/kernel/git/dakr/linux.git/log/?h=rust/mm This patch (of 2): Implement vrealloc() analogous to krealloc(). Currently, krealloc() requires the caller to pass the size of the previous memory allocation, which, instead, should be self-contained. We attempt to fix this in a subsequent patch which, in order to do so, requires vrealloc(). Besides that, we need realloc() functions for kernel allocators in Rust too. With `Vec` or `KVec` respectively, potentially growing (and shrinking) data structures are rather common. [dakr@kernel.org: fix missing nommu implementation] Link: https://lkml.kernel.org/r/20240725141227.13954-1-dakr@kernel.org [dakr@kernel.org: document concurrency restrictions] Link: https://lkml.kernel.org/r/20240725125442.4957-1-dakr@kernel.org [dakr@kernel.org: consider spare memory for __GFP_ZERO] Link: https://lkml.kernel.org/r/20240730185049.6244-3-dakr@kernel.org [dakr@kernel.org: properly document __GFP_ZERO behavior] Link: https://lkml.kernel.org/r/20240730185049.6244-4-dakr@kernel.org Link: https://lkml.kernel.org/r/20240722163111.4766-1-dakr@kernel.org Link: https://lkml.kernel.org/r/20240722163111.4766-2-dakr@kernel.orgSigned-off-by:
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Matthew Cassell authored
/proc/vmstat currently shows the number of node_reclaim() failures when vm.zone_reclaim_mode is set appropriately. It would be convenient to have the number of successes right next to zone_reclaim_failed (similar to compaction and migration). While just a trivially addition to the vmstat file. It was helpful during benchmarking to not have to probe node_reclaim() to observe the success/failure ratio. Link: https://lkml.kernel.org/r/20240722171316.7517-1-mcassell411@gmail.comSigned-off-by:
Matthew Cassell <mcassell411@gmail.com> Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Li Zhijian <lizhijian@fujitsu.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by:
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- 01 Sep, 2024 3 commits
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Linus Torvalds authored
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git://git.samba.org/sfrench/cifs-2.6Linus Torvalds authored
Pull smb client fixes from Steve French: - copy_file_range fix - two read fixes including read past end of file rc fix and read retry crediting fix - falloc zero range fix * tag 'v6.11-rc5-smb-client-fixes' of git://git.samba.org/sfrench/cifs-2.6: cifs: Fix FALLOC_FL_ZERO_RANGE to preflush buffered part of target region cifs: Fix copy offload to flush destination region netfs, cifs: Fix handling of short DIO read cifs: Fix lack of credit renegotiation on read retry
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https://github.com/koverstreet/bcachefsLinus Torvalds authored
Push bcachefs fixes from Kent Overstreet: "The data corruption in the buffered write path is troubling; inode lock should not have been able to cause that... - Fix a rare data corruption in the rebalance path, caught as a nonce inconsistency on encrypted filesystems - Revert lockless buffered write path - Mark more errors as autofix" * tag 'bcachefs-2024-08-21' of https://github.com/koverstreet/bcachefs: bcachefs: Mark more errors as autofix bcachefs: Revert lockless buffered IO path bcachefs: Fix bch2_extents_match() false positive bcachefs: Fix failure to return error in data_update_index_update()
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- 31 Aug, 2024 4 commits
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Kent Overstreet authored
errors that are known to always be safe to fix should be autofix: this should be most errors even at this point, but that will need some thorough review. note that errors are still logged in the superblock, so we'll still know that they happened. Signed-off-by: -
Kent Overstreet authored
We had a report of data corruption on nixos when building installer images. https://github.com/NixOS/nixpkgs/pull/321055#issuecomment-2184131334 It seems that writes are being dropped, but only when issued by QEMU, and possibly only in snapshot mode. It's undetermined if it's write calls are being dropped or dirty folios. Further testing, via minimizing the original patch to just the change that skips the inode lock on non appends/truncates, reveals that it really is just not taking the inode lock that causes the corruption: it has nothing to do with the other logic changes for preserving write atomicity in corner cases. It's also kernel config dependent: it doesn't reproduce with the minimal kernel config that ktest uses, but it does reproduce with nixos's distro config. Bisection the kernel config initially pointer the finger at page migration or compaction, but it appears that was erroneous; we haven't yet determined what kernel config option actually triggers it. Sadly it appears this will have to be reverted since we're getting too close to release and my plate is full, but we'd _really_ like to fully debug it. My suspicion is that this patch is exposing a preexisting bug - the inode lock actually covers very little in IO paths, and we have a different lock (the pagecache add lock) that guards against races with truncate here. Fixes: 7e64c86c ("bcachefs: Buffered write path now can avoid the inode lock") Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-stagingLinus Torvalds authored
Pull misc fixes from Guenter Roeck. These are fixes for regressions that Guenther has been reporting, and the maintainers haven't picked up and sent in. With rc6 fairly imminent, I'm taking them directly from Guenter. * 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: apparmor: fix policy_unpack_test on big endian systems Revert "MIPS: csrc-r4k: Apply verification clocksource flags" microblaze: don't treat zero reserved memory regions as error
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git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linuxLinus Torvalds authored
Pull power sequencing fix from Bartosz Golaszewski: "A follow-up fix for the power sequencing subsystem. It turned out the previous fix for this driver was incomplete and broke the WLAN support on some platforms. This addresses the issue. - set the direction of the wlan-enable GPIO to output after requesting it as-is" * tag 'pwrseq-fixes-for-v6.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux: power: sequencing: qcom-wcn: set the wlan-enable GPIO to output
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