Patch series "mm: Use hotplug_memory_notifier() instead of
register_hotmemory_notifier()", v4.
Commit f02c696800 ("include/linux/memory.h: implement
register_hotmemory_notifier()") introduced register_hotmemory_notifier()
to avoid a compile problem with gcc-4.4.4:
When CONFIG_MEMORY_HOTPLUG=n, we don't want the memory-hotplug notifier
handlers to be included in the .o files, for space reasons.
The existing hotplug_memory_notifier() tries to handle this but testing
with gcc-4.4.4 shows that it doesn't work - the hotplug functions are
still present in the .o files.
Since commit 76ae847497 ("Documentation: raise minimum supported
version of GCC to 5.1") has already updated the minimum gcc version to
5.1. The previous problem mentioned in f02c696800 does not exist. So
we can now revert to use hotplug_memory_notifier() directly rather than
register_hotmemory_notifier().
In the last patch, we move all hotplug memory notifier priority to same
file for easy sorting.
This patch (of 8):
Commit 76ae847497 ("Documentation: raise minimum supported version of
GCC to 5.1") updated the minimum gcc version to 5.1. So the problem
mentioned in f02c696800 ("include/linux/memory.h: implement
register_hotmemory_notifier()") no longer exist. So we can now switch to
use hotplug_memory_notifier() directly rather than
register_hotmemory_notifier().
Link: https://lkml.kernel.org/r/20220923033347.3935160-1-liushixin2@huawei.com
Link: https://lkml.kernel.org/r/20220923033347.3935160-2-liushixin2@huawei.com
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Waiman Long <longman@redhat.com>
Cc: zefan li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Let's run all existing test cases with all hugetlb sizes we're able to
detect.
Note that some tests cases still fail. This will, for example, be fixed
once vmsplice properly uses FOLL_PIN instead of FOLL_GET for pinning.
With 2 MiB and 1 GiB hugetlb on x86_64, the expected failures are:
# [RUN] vmsplice() + unmap in child ... with hugetlb (2048 kB)
not ok 23 No leak from parent into child
# [RUN] vmsplice() + unmap in child ... with hugetlb (1048576 kB)
not ok 24 No leak from parent into child
# [RUN] vmsplice() before fork(), unmap in parent after fork() ... with hugetlb (2048 kB)
not ok 35 No leak from child into parent
# [RUN] vmsplice() before fork(), unmap in parent after fork() ... with hugetlb (1048576 kB)
not ok 36 No leak from child into parent
# [RUN] vmsplice() + unmap in parent after fork() ... with hugetlb (2048 kB)
not ok 47 No leak from child into parent
# [RUN] vmsplice() + unmap in parent after fork() ... with hugetlb (1048576 kB)
not ok 48 No leak from child into parent
Link: https://lkml.kernel.org/r/20220927110120.106906-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph von Recklinghausen <crecklin@redhat.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "selftests/vm: test COW handling of anonymous memory".
This is my current set of tests for testing COW handling of anonymous
memory, especially when interacting with GUP. I developed these tests
while working on PageAnonExclusive and managed to clean them up just now.
On current upstream Linux, all tests pass except the hugetlb tests that
rely on vmsplice -- these tests should pass as soon as vmsplice properly
uses FOLL_PIN instead of FOLL_GET.
I'm working on additional tests for COW handling in private mappings,
focusing on long-term R/O pinning e.g., of the shared zeropage, pagecache
pages and KSM pages. These tests, however, will go into a different file.
So this is everything I have regarding tests for anonymous memory.
This patch (of 7):
Let's start adding tests for our COW handling of anonymous memory. We'll
focus on basic tests that we can achieve without additional libraries or
gup_test extensions.
We'll add THP and hugetlb tests separately.
[david@redhat.com: s/size_t/ssize_t/ on `cur', `total', `transferred';]
Link: https://lkml.kernel.org/r/51302b9e-dc69-d709-3214-f23868028555@redhat.com
Link: https://lkml.kernel.org/r/20220927110120.106906-1-david@redhat.com
Link: https://lkml.kernel.org/r/20220927110120.106906-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Christoph von Recklinghausen <crecklin@redhat.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Nadav Amit <namit@vmware.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Migrate the kasan_rcu_uaf test to the KUnit framework.
Changes to the implementation of the test:
- Call rcu_barrier() after call_rcu() to make that the RCU callbacks get
triggered before the test is over.
- Cast pointer passed to rcu_dereference_protected as __rcu to get rid of
the Sparse warning.
- Check that KASAN prints a report via KUNIT_EXPECT_KASAN_FAIL.
Initially, this test was intended to check that Generic KASAN prints
auxiliary stack traces for RCU objects. Nevertheless, the test is enabled
for all modes to make that KASAN reports bad accesses in RCU callbacks.
The presence of auxiliary stack traces for the Generic mode needs to be
inspected manually.
Link: https://lkml.kernel.org/r/897ee08d6cd0ba7e8a4fbfd9d8502823a2f922e6.1664298455.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in
update_used_max. x86 CMPXCHG instruction returns success in ZF flag, so
this change saves a compare after cmpxchg (and related move instruction in
front of cmpxchg).
Also, reorder code a bit to remove additional compare and conditional jump
from the assembly code. Together, hese two changes save 15 bytes from the
function when compiled for x86_64.
No functional change intended.
Link: https://lkml.kernel.org/r/20221018145154.3699-1-ubizjak@gmail.com
Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Initially, find_get_entries() was being passed in the start offset as a
value. That left the calculation of the offset to the callers. This led
to complexity in the callers trying to keep track of the index.
Now find_get_entries() takes in a pointer to the start offset and updates
the value to be directly after the last entry found. If no entry is
found, the offset is not changed. This gets rid of multiple hacky
calculations that kept track of the start offset.
Link: https://lkml.kernel.org/r/20221017161800.2003-3-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "Rework find_get_entries() and find_lock_entries()", v3.
Originally the callers of find_get_entries() and find_lock_entries() were
keeping track of the start index themselves as they traverse the search
range.
This resulted in hacky code such as in shmem_undo_range():
index = folio->index + folio_nr_pages(folio) - 1;
where the - 1 is only present to stay in the right spot after incrementing
index later. This sort of calculation was also being done on every folio
despite not even using index later within that function.
These patches change find_get_entries() and find_lock_entries() to
calculate the new index instead of leaving it to the callers so we can
avoid all these complications.
This patch (of 2):
Initially, find_lock_entries() was being passed in the start offset as a
value. That left the calculation of the offset to the callers. This led
to complexity in the callers trying to keep track of the index.
Now find_lock_entries() takes in a pointer to the start offset and updates
the value to be directly after the last entry found. If no entry is
found, the offset is not changed. This gets rid of multiple hacky
calculations that kept track of the start offset.
Link: https://lkml.kernel.org/r/20221017161800.2003-1-vishal.moola@gmail.com
Link: https://lkml.kernel.org/r/20221017161800.2003-2-vishal.moola@gmail.com
Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "begin converting hugetlb code to folios", v4.
This patch series starts the conversion of the hugetlb code to operate on
struct folios rather than struct pages. This removes the ambiguitiy of
whether functions are operating on head pages, tail pages of compound
pages, or base pages.
This series passes the linux test project hugetlb test cases.
Patch 1 adds hugeltb specific page macros that can operate on folios.
Patch 2 adds the private field of the first tail page to struct page. For
32-bit, _private_1 alinging with page[1].private was confirmed by using
pahole.
Patch 3 introduces hugetlb subpool helper functions which operate on
struct folios. These patches were tested using the hugepage-mmap.c
selftest along with the migratepages command.
Patch 4 converts hugetlb_delete_from_page_cache() to use folios.
Patch 5 adds a folio_hstate() function to get hstate information from a
folio and adds a user of folio_hstate().
Bpftrace was used to track time spent in the free_huge_pages function
during the ltp test cases as it is a caller of the hugetlb subpool
functions. From the histogram, the performance is similar before and
after the patch series.
Time spent in 'free_huge_page'
6.0.0-rc2.master.20220823
@nsecs:
[256, 512) 14770 |@@@@@@@@@@@@@@@@@@@@@@@@@@@
|@@@@@@@@@@@@@@@@@@@@@@@@@ |
[512, 1K) 155 | |
[1K, 2K) 169 | |
[2K, 4K) 50 | |
[4K, 8K) 14 | |
[8K, 16K) 3 | |
[16K, 32K) 3 | |
6.0.0-rc2.master.20220823 + patch series
@nsecs:
[256, 512) 13678 |@@@@@@@@@@@@@@@@@@@@@@@@@@@ |
|@@@@@@@@@@@@@@@@@@@@@@@@@ |
[512, 1K) 142 | |
[1K, 2K) 199 | |
[2K, 4K) 44 | |
[4K, 8K) 13 | |
[8K, 16K) 4 | |
[16K, 32K) 1 | |
This patch (of 5):
Allow the macros which test, set, and clear hugetlb specific page flags to
take a hugetlb folio as an input. The macrros are generated as
folio_{test, set, clear}_hugetlb_{restore_reserve, migratable, temporary,
freed, vmemmap_optimized, raw_hwp_unreliable}.
Link: https://lkml.kernel.org/r/20220922154207.1575343-1-sidhartha.kumar@oracle.com
Link: https://lkml.kernel.org/r/20220922154207.1575343-2-sidhartha.kumar@oracle.com
Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Colin Cross <ccross@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: William Kucharski <william.kucharski@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
