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234 commits

Author SHA1 Message Date
Zhansaya Bagdauletkyzy 924a11bd16 selftests: vm: add COW time test for KSM pages
Since merged pages are copied every time they need to be modified, the
write access time is different between shared and non-shared pages.  Add
ksm_cow_time() function which evaluates latency of these COW breaks.
First, 4000 pages are allocated and the time, required to modify 1 byte in
every other page, is measured.  After this, the pages are merged into 2000
pairs and in each pair, 1 page is modified (i.e.  they are decoupled) to
detect COW breaks.  The time needed to break COW of merged pages is then
compared with performance of non-shared pages.

The test is run as follows: ./ksm_tests -C
The output:
	Total size:    15 MiB

	Not merged pages:
	Total time:     0.002185489 s
	Average speed:  3202.945 MiB/s

	Merged pages:
	Total time:     0.004386872 s
	Average speed:  1595.670 MiB/s

Link: https://lkml.kernel.org/r/1d03ee0d1b341959d4b61672c6401d498bff5652.1629386192.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Zhansaya Bagdauletkyzy 9e7cb94ca2 selftests: vm: add KSM merging time test
Patch series "add KSM performance tests", v3.

Extend KSM self tests with a performance benchmark.  These tests are not
part of regular regression testing, as they are mainly intended to be used
by developers making changes to the memory management subsystem.

This patch (of 2):

Add ksm_merge_time() function to determine speed and time needed for
merging.  The total spent time is shown in seconds while speed is in
MiB/s.  User must specify the size of duplicated memory area (in MiB)
before running the test.

The test is run as follows: ./ksm_tests -P -s 100
The output:
	Total size:    100 MiB
	Total time:    0.201106786 s
	Average speed:  497.248 MiB/s

Link: https://lkml.kernel.org/r/cover.1629386192.git.zhansayabagdaulet@gmail.com
Link: https://lkml.kernel.org/r/318b946ac80cc9205c89d0962048378f7ce0705b.1629386192.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Zhansaya Bagdauletkyzy 82e717ad35 selftests: vm: add KSM merging across nodes test
Add check_ksm_numa_merge() function to test that pages in different NUMA
nodes are being handled properly.  First, two duplicate pages are
allocated in two separate NUMA nodes using the libnuma library.  Since
there is one unique page in each node, with merge_across_nodes = 0, there
won't be any shared pages.  If merge_across_nodes is set to 1, the pages
will be treated as usual duplicate pages and will be merged.  If NUMA
config is not enabled or the number of NUMA nodes is less than two, then
the test is skipped.  The test is run as follows: ./ksm_tests -N

Link: https://lkml.kernel.org/r/071c17b5b04ebb0dfeba137acc495e5dd9d2a719.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Zhansaya Bagdauletkyzy 39619982c5 selftests: vm: add KSM zero page merging test
Add check_ksm_zero_page_merge() function to test that empty pages are
being handled properly.  For this, several zero pages are allocated and
merged using madvise.  If use_zero_pages is enabled, the pages must be
shared with the special kernel zero pages; otherwise, they are merged as
usual duplicate pages.  The test is run as follows: ./ksm_tests -Z

Link: https://lkml.kernel.org/r/6d0caab00d4bdccf5e3791cb95cf6dfd5eb85e45.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Zhansaya Bagdauletkyzy a40c80e348 selftests: vm: add KSM unmerge test
Add check_ksm_unmerge() function to verify that KSM is properly unmerging
shared pages.  For this, two duplicate pages are merged first and then
their contents are modified.  Since they are not identical anymore, the
pages must be unmerged and the number of merged pages has to be 0.  The
test is run as follows: ./ksm_tests -U

Link: https://lkml.kernel.org/r/c0f55420440d704d5b094275b4365aa1b2ad46b5.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Zhansaya Bagdauletkyzy 68d6289baa selftests: vm: add KSM merge test
Patch series "add KSM selftests".

Introduce selftests to validate the functionality of KSM.  The tests are
run on private anonymous pages.  Since some KSM tunables are modified,
their starting values are saved and restored after testing.  At the start,
run is set to 2 to ensure that only test pages will be merged (we assume
that no applications make madvise syscalls in the background).  If KSM
config not enabled, all tests will be skipped.

This patch (of 4):

Add check_ksm_merge() function to check the basic merging feature of KSM.
First, some number of identical pages are allocated and the MADV_MERGEABLE
advice is given to merge these pages.  Then, pages_shared and
pages_sharing values are compared with the expected numbers using
assert_ksm_pages_count() function.  The number of pages can be changed
using -p option.

Link: https://lkml.kernel.org/r/cover.1626252248.git.zhansayabagdaulet@gmail.com
Link: https://lkml.kernel.org/r/90287685c13300972ea84de93d1f3f900373f9fe.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:18 -07:00
Nadav Amit 4410cbb5c9 selftests/vm/userfaultfd: wake after copy failure
When userfaultfd copy-ioctl fails since the PTE already exists, an -EEXIST
error is returned and the faulting thread is not woken.  The current
userfaultfd test does not wake the faulting thread in such case.  The
assumption is presumably that another thread set the PTE through copy/wp
ioctl and would wake the faulting thread or that alternatively the fault
handler would realize there is no need to "must_wait" and continue.  This
is not necessarily true.

There is an assumption that the "must_wait" tests in handle_userfault()
are sufficient to provide definitive answer whether the offending PTE is
populated or not.  However, userfaultfd_must_wait() test is lockless.
Consequently, concurrent calls to ptep_modify_prot_start(), for instance,
can clear the PTE and can cause userfaultfd_must_wait() to wrongly assume
it is not populated and a wait is needed.

There are therefore 3 options:
(1) Change the tests to wake on copy failure.
(2) Wake faulting thread unconditionally on zero/copy ioctls before
    returning -EEXIST.
(3) Change the userfaultfd_must_wait() to hold locks.

This patch took the first approach, but the others are valid solutions
with different tradeoffs.

Link: https://lkml.kernel.org/r/20210808020724.1022515-4-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:16 -07:00
Colin Ian King 0c52ec9513 selftests: Fix spelling mistake "cann't" -> "cannot"
There is a spelling mistake in an error message. Fix it.

Link: https://lkml.kernel.org/r/20210826121217.12885-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Po-Hsu Lin 6260618e09 selftests/vm: use kselftest skip code for skipped tests
There are several test cases in the vm directory are still using exit 0
when they need to be skipped.  Use the kselftest framework to skip code
instead so it can help us to distinguish the return status.

Criterion to filter out what should be fixed in vm directory:
  grep -r "exit 0" -B1 | grep -i skip

This change might cause some false-positives if people are running these
test scripts directly and only checking their return codes, which will
change from 0 to 4.  However I think the impact should be small as most of
our scripts here are already using this skip code.  And there will be no
such issue if running them with the kselftest framework.

Link: https://lkml.kernel.org/r/20210823073433.37653-1-po-hsu.lin@canonical.com
Signed-off-by: Po-Hsu Lin <po-hsu.lin@canonical.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:13 -07:00
Peter Collingbourne 0db282ba2c selftest: use mmap instead of posix_memalign to allocate memory
This test passes pointers obtained from anon_allocate_area to the
userfaultfd and mremap APIs.  This causes a problem if the system
allocator returns tagged pointers because with the tagged address ABI
the kernel rejects tagged addresses passed to these APIs, which would
end up causing the test to fail.  To make this test compatible with such
system allocators, stop using the system allocator to allocate memory in
anon_allocate_area, and instead just use mmap.

Link: https://lkml.kernel.org/r/20210714195437.118982-3-pcc@google.com
Link: https://linux-review.googlesource.com/id/Icac91064fcd923f77a83e8e133f8631c5b8fc241
Fixes: c47174fc36 ("userfaultfd: selftest")
Co-developed-by: Lokesh Gidra <lokeshgidra@google.com>
Signed-off-by: Lokesh Gidra <lokeshgidra@google.com>
Signed-off-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Alistair Delva <adelva@google.com>
Cc: William McVicker <willmcvicker@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mitch Phillips <mitchp@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: <stable@vger.kernel.org>	[5.4]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-23 17:43:28 -07:00
Aneesh Kumar K.V a9cc9c3456 selftest/mremap_test: avoid crash with static build
With a large mmap map size, we can overlap with the text area and using
MAP_FIXED results in unmapping that area.  Switch to MAP_FIXED_NOREPLACE
and handle the EEXIST error.

Link: https://lkml.kernel.org/r/20210616045239.370802-3-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Kalesh Singh <kaleshsingh@google.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Hugh Dickins <hughd@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:22 -07:00
Aneesh Kumar K.V f27a5c93cd selftest/mremap_test: update the test to handle pagesize other than 4K
Patch series "mrermap fixes", v2.

This patch (of 6):

Instead of hardcoding 4K page size fetch it using sysconf().  For the
performance measurements test still assume 2M and 1G are hugepage sizes.

Link: https://lkml.kernel.org/r/20210616045239.370802-1-aneesh.kumar@linux.ibm.com
Link: https://lkml.kernel.org/r/20210616045239.370802-2-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Reviewed-by: Kalesh Singh <kaleshsingh@google.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:22 -07:00
Mike Rapoport 76fe17ef58 secretmem: test: add basic selftest for memfd_secret(2)
The test verifies that file descriptor created with memfd_secret does not
allow read/write operations, that secret memory mappings respect
RLIMIT_MEMLOCK and that remote accesses with process_vm_read() and
ptrace() to the secret memory fail.

Link: https://lkml.kernel.org/r/20210518072034.31572-8-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christopher Lameter <cl@linux.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Hagen Paul Pfeifer <hagen@jauu.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rick Edgecombe <rick.p.edgecombe@intel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Will Deacon <will@kernel.org>
Cc: kernel test robot <lkp@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-08 11:48:21 -07:00
Dave Hansen d892454b68 selftests/vm/pkeys: exercise x86 XSAVE init state
On x86, there is a set of instructions used to save and restore register
state collectively known as the XSAVE architecture.  There are about a
dozen different features managed with XSAVE.  The protection keys
register, PKRU, is one of those features.

The hardware optimizes XSAVE by tracking when the state has not changed
from its initial (init) state.  In this case, it can avoid the cost of
writing state to memory (it would usually just be a bunch of 0's).

When the pkey register is 0x0 the hardware optionally choose to track the
register as being in the init state (optimize away the writes).  AMD CPUs
do this more aggressively compared to Intel.

On x86, PKRU is rarely in its (very permissive) init state.  Instead, the
value defaults to something very restrictive.  It is not surprising that
bugs have popped up in the rare cases when PKRU reaches its init state.

Add a protection key selftest which gets the protection keys register into
its init state in a way that should work on Intel and AMD.  Then, do a
bunch of pkey register reads to watch for inadvertent changes.

This adds "-mxsave" to CFLAGS for all the x86 vm selftests in order to
allow use of the XSAVE instruction __builtin functions.  This will make
the builtins available on all of the vm selftests, but is expected to be
harmless.

Link: https://lkml.kernel.org/r/20210611164202.1849B712@viggo.jf.intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:06 -07:00
Dave Hansen 6039ca2549 selftests/vm/pkeys: refill shadow register after implicit kernel write
The pkey test code keeps a "shadow" of the pkey register around.  This
ensures that any bugs which might write to the register can be caught more
quickly.

Generally, userspace has a good idea when the kernel is going to write to
the register.  For instance, alloc_pkey() is passed a permission mask.
The caller of alloc_pkey() can update the shadow based on the return value
and the mask.

But, the kernel can also modify the pkey register in a more sneaky way.
For mprotect(PROT_EXEC) mappings, the kernel will allocate a pkey and
write the pkey register to create an execute-only mapping.  The kernel
never tells userspace what key it uses for this.

This can cause the test to fail with messages like:

	protection_keys_64.2: pkey-helpers.h:132: _read_pkey_reg: Assertion `pkey_reg == shadow_pkey_reg' failed.

because the shadow was not updated with the new kernel-set value.

Forcibly update the shadow value immediately after an mprotect().

Link: https://lkml.kernel.org/r/20210611164200.EF76AB73@viggo.jf.intel.com
Fixes: 6af17cf89e ("x86/pkeys/selftests: Add PROT_EXEC test")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:06 -07:00
Dave Hansen bf68294a2e selftests/vm/pkeys: handle negative sys_pkey_alloc() return code
The alloc_pkey() sefltest function wraps the sys_pkey_alloc() system call.
On success, it updates its "shadow" register value because
sys_pkey_alloc() updates the real register.

But, the success check is wrong.  pkey_alloc() considers any non-zero
return code to indicate success where the pkey register will be modified.
This fails to take negative return codes into account.

Consider only a positive return value as a successful call.

Link: https://lkml.kernel.org/r/20210611164157.87AB4246@viggo.jf.intel.com
Fixes: 5f23f6d082 ("x86/pkeys: Add self-tests")
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:06 -07:00
Dave Hansen f36ef40762 selftests/vm/pkeys: fix alloc_random_pkey() to make it really, really random
Patch series "selftests/vm/pkeys: Bug fixes and a new test".

There has been a lot of activity on the x86 front around the XSAVE
architecture which is used to context-switch processor state (among other
things).  In addition, AMD has recently joined the protection keys club by
adding processor support for PKU.

The AMD implementation helped uncover a kernel bug around the PKRU "init
state", which actually applied to Intel's implementation but was just
harder to hit.  This series adds a test which is expected to help find
this class of bug both on AMD and Intel.  All the work around pkeys on x86
also uncovered a few bugs in the selftest.

This patch (of 4):

The "random" pkey allocation code currently does the good old:

	srand((unsigned int)time(NULL));

*But*, it unfortunately does this on every random pkey allocation.

There may be thousands of these a second.  time() has a one second
resolution.  So, each time alloc_random_pkey() is called, the PRNG is
*RESET* to time().  This is nasty.  Normally, if you do:

	srand(<ANYTHING>);
	foo = rand();
	bar = rand();

You'll be quite guaranteed that 'foo' and 'bar' are different.  But, if
you do:

	srand(1);
	foo = rand();
	srand(1);
	bar = rand();

You are quite guaranteed that 'foo' and 'bar' are the *SAME*.  The recent
"fix" effectively forced the test case to use the same "random" pkey for
the whole test, unless the test run crossed a second boundary.

Only run srand() once at program startup.

This explains some very odd and persistent test failures I've been seeing.

Link: https://lkml.kernel.org/r/20210611164153.91B76FB8@viggo.jf.intel.com
Link: https://lkml.kernel.org/r/20210611164155.192D00FF@viggo.jf.intel.com
Fixes: 6e373263ce ("selftests/vm/pkeys: fix alloc_random_pkey() to make it really random")
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: "Desnes A. Nunes do Rosario" <desnesn@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Suchanek <msuchanek@suse.de>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:06 -07:00
Alistair Popple b659baea75 mm: selftests for exclusive device memory
Adds some selftests for exclusive device memory.

Link: https://lkml.kernel.org/r/20210616105937.23201-9-apopple@nvidia.com
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-01 11:06:03 -07:00
David Hildenbrand e5bfac53e3 selftests/vm: add test for MADV_POPULATE_(READ|WRITE)
Let's add a simple test for MADV_POPULATE_READ and MADV_POPULATE_WRITE,
verifying some error handling, that population works, and that softdirty
tracking works as expected.  For now, limit the test to private anonymous
memory.

Link: https://lkml.kernel.org/r/20210419135443.12822-6-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:31 -07:00
David Hildenbrand 2abdd8b8a2 selftests/vm: add protection_keys_32 / protection_keys_64 to gitignore
We missed adding two binaries to gitignore.

Link: https://lkml.kernel.org/r/20210419135443.12822-5-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Peter Xu <peterx@redhat.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chris Zankel <chris@zankel.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Jann Horn <jannh@google.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Rolf Eike Beer <eike-kernel@sf-tec.de>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:31 -07:00
Axel Rasmussen 4a8f021ba0 userfaultfd/selftests: exercise minor fault handling shmem support
Enable test_uffdio_minor for test_type == TEST_SHMEM, and modify the test
slightly to pass in / check for the right feature flags.

Link: https://lkml.kernel.org/r/20210503180737.2487560-11-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:28 -07:00
Axel Rasmussen 8ba6e86408 userfaultfd/selftests: reinitialize test context in each test
Currently, the context (fds, mmap-ed areas, etc.) are global.  Each test
mutates this state in some way, in some cases really "clobbering it"
(e.g., the events test mremap-ing area_dst over the top of area_src, or
the minor faults tests overwriting the count_verify values in the test
areas).  We run the tests in a particular order, each test is careful to
make the right assumptions about its starting state, etc.

But, this is fragile.  It's better for a test's success or failure to not
depend on what some other prior test case did to the global state.

To that end, clear and reinitialize the test context at the start of each
test case, so whatever prior test cases did doesn't affect future tests.

This is particularly relevant to this series because the events test's
mremap of area_dst screws up assumptions the minor fault test was relying
on.  This wasn't a problem for hugetlb, as we don't mremap in that case.

[peterx@redhat.com: fix conflict between this patch and the uffd pagemap series]
  Link: https://lkml.kernel.org/r/YKQqKrl+/cQ1utrb@t490s

Link: https://lkml.kernel.org/r/20210503180737.2487560-10-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:28 -07:00
Axel Rasmussen 5bb23edb18 userfaultfd/selftests: create alias mappings in the shmem test
Previously, we just allocated two shm areas: area_src and area_dst.  With
this commit, change this so we also allocate area_src_alias, and
area_dst_alias.

area_*_alias and area_* (respectively) point to the same underlying
physical pages, but are different VMAs.  In a future commit in this
series, we'll leverage this setup to exercise minor fault handling support
for shmem, just like we do in the hugetlb_shared test.

Link: https://lkml.kernel.org/r/20210503180737.2487560-9-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Axel Rasmussen fa2c2b5818 userfaultfd/selftests: use memfd_create for shmem test type
This is a preparatory commit.  In the future, we want to be able to setup
alias mappings for area_src and area_dst in the shmem test, like we do in
the hugetlb_shared test.  With a VMA obtained via mmap(MAP_ANONYMOUS |
MAP_SHARED), it isn't clear how to do this.

So, mmap() with an fd, so we can create alias mappings.  Use memfd_create
instead of actually passing in a tmpfs path like hugetlb does, since it's
more convenient / simpler to run, and works just as well.

Future commits will:

1. Setup the alias mappings.
2. Extend our tests to actually take advantage of this, to test new
   userfaultfd behavior being introduced in this series.

Also, a small fix in the area we're changing: when the hugetlb setup fails
in main(), pass in the right argv[] so we actually print out the hugetlb
file path.

Link: https://lkml.kernel.org/r/20210503180737.2487560-8-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu eb3b2e0039 userfaultfd/selftests: add pagemap uffd-wp test
Add one anonymous specific test to start using pagemap.  With pagemap
support, we can directly read the uffd-wp bit from pgtable without
triggering any fault, so it's easier to do sanity checks in unit tests.

Meanwhile this test also leverages the newly introduced MADV_PAGEOUT
madvise function to test swap ptes with uffd-wp bit set, and across
fork()s.

Link: https://lkml.kernel.org/r/20210428225030.9708-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu 42e584eede userfaultfd/selftests: unify error handling
Introduce err()/_err() and replace all the different ways to fail the
program, mostly "fprintf" and "perror" with tons of exit() calls.  Always
stop the test program at any failure.

Link: https://lkml.kernel.org/r/20210412232753.1012412-6-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu de3ca8e4a5 userfaultfd/selftests: only dump counts if mode enabled
WP and MINOR modes are conditionally enabled on specific memory types.
This patch avoids dumping tons of zeros for those cases when the modes are
not supported at all.

Link: https://lkml.kernel.org/r/20210412232753.1012412-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu 4e08e18a78 userfaultfd/selftests: dropping VERIFY check in locking_thread
It tries to check against all zeros and looped for quite a few times.
However after that we'll verify the same page with count_verify, while
count_verify can never be zero.  So it means if it's a zero page we'll
detect it anyways with below code.

There's yet another place we conditionally check the fault flag - just do
it unconditionally.

Link: https://lkml.kernel.org/r/20210412232753.1012412-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu ba4f8c355e userfaultfd/selftests: remove the time() check on delayed uffd
There seems to have no guarantee that time() will return the same for the
two calls even if there's no delay, e.g.  when a fault is accidentally
crossing the changing of a second.  Meanwhile, this message is also not
helping that much since delay could happen with a lot of reasons, e.g.,
schedule latency of resolving thread.  It may not mean an issue with uffd.

Neither do I saw this error triggered either in the past runs.  Even if it
triggers, it'll be drown in all the rest of test logs.  Remove it.

Link: https://lkml.kernel.org/r/20210412232753.1012412-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Peter Xu d2c6c06fff userfaultfd/selftests: use user mode only
Patch series "userfaultfd/selftests: A few cleanups", v2.

I wanted to cleanup userfaultfd.c fault handling for a long time.  If it's
not cleaned, when the new code grows the file it'll also grow the size
that needs to be cleaned...  This is my attempt to cleanup the userfaultfd
selftest on fault handling, to use an err() macro instead of either
fprintf() or perror() then another exit() call.

The huge cleanup is done in the last patch.  The first 4 patches are some
other standalone cleanups for the same file, so I put them together.

This patch (of 5):

Userfaultfd selftest does not need to handle kernel initiated fault.  Set
user mode so it can be run even if unprivileged_userfaultfd=0 (which is
the default).

Link: https://lkml.kernel.org/r/20210412232753.1012412-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Brian Geffon <bgeffon@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:27 -07:00
Nanyong Sun 22f3c95186 khugepaged: selftests: remove debug_cow
The debug_cow attribute had been removed since commit 4958e4d86e ("mm:
thp: remove debug_cow switch"), so remove it in selftest code too,
otherwise the khugepaged test will fail.

Link: https://lkml.kernel.org/r/20210430051117.400189-1-sunnanyong@huawei.com
Fixes: 4958e4d86e ("mm: thp: remove debug_cow switch")
Signed-off-by: Nanyong Sun <sunnanyong@huawei.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-30 20:47:26 -07:00
Peter Xu f39bd85345 mm/gup_benchmark: support threading
Patch series "mm/gup: Fix pin page write cache bouncing on has_pinned", v2.

This series contains 3 patches, the 1st one enables threading for
gup_benchmark in the kselftest.  The latter two patches are collected from
Andrea's local branch which can fix write cache bouncing issue with
pinning fast-gup.

To be explicit on the latter two patches:

  - the 2nd patch fixes the perf degrade when introducing has_pinned, then

  - the last patch tries to remove the has_pinned with a bit in mm->flags

For patch 3: originally I think we had a plan to reuse has_pinned into a
counter very soon, however that's not happening at least until today, so
maybe it proves that we can remove it until we really want such a counter
for whatever reason.  As the commit message stated, it saves 4 bytes for
each mm without observable regressions.

Regarding testing: we can reference to the commit message of patch 2 for
some detailed testing with will-is-scale.  Meanwhile I did patch 1 just
because then we can even easily verify the patchset using the existing
kselftest facilities or even regress test it in the future with the repo
if we want.

Below numbers are extra verification tests that I did besides commit
message of patch 2 using the new gup_benchmark and 256 cpus.  Below test
is done on 40 cpus host with Intel(R) Xeon(R) CPU E5-2630 v4 @ 2.20GHz,
and I can get similar result (of course the write cache bouncing get
severe with even more cores).

After patch 1 applied (only test patch, so using old kernel):

  $ sudo chrt -f 1 ./gup_test -a  -m 512 -j 40
  PIN_FAST_BENCHMARK: Time: get:459632 put:5990 us
  PIN_FAST_BENCHMARK: Time: get:461967 put:5840 us
  PIN_FAST_BENCHMARK: Time: get:464521 put:6140 us
  PIN_FAST_BENCHMARK: Time: get:465176 put:7100 us
  PIN_FAST_BENCHMARK: Time: get:465960 put:6733 us
  PIN_FAST_BENCHMARK: Time: get:465324 put:6781 us
  PIN_FAST_BENCHMARK: Time: get:466018 put:7130 us
  PIN_FAST_BENCHMARK: Time: get:466362 put:7118 us
  PIN_FAST_BENCHMARK: Time: get:465118 put:6975 us
  PIN_FAST_BENCHMARK: Time: get:466422 put:6602 us
  PIN_FAST_BENCHMARK: Time: get:465791 put:6818 us
  PIN_FAST_BENCHMARK: Time: get:467091 put:6298 us
  PIN_FAST_BENCHMARK: Time: get:467694 put:5432 us
  PIN_FAST_BENCHMARK: Time: get:469575 put:5581 us
  PIN_FAST_BENCHMARK: Time: get:468124 put:6055 us
  PIN_FAST_BENCHMARK: Time: get:468877 put:6720 us
  PIN_FAST_BENCHMARK: Time: get:467212 put:4961 us
  PIN_FAST_BENCHMARK: Time: get:467834 put:6697 us
  PIN_FAST_BENCHMARK: Time: get:470778 put:6398 us
  PIN_FAST_BENCHMARK: Time: get:469788 put:6310 us
  PIN_FAST_BENCHMARK: Time: get:488277 put:7113 us
  PIN_FAST_BENCHMARK: Time: get:486613 put:7085 us
  PIN_FAST_BENCHMARK: Time: get:486940 put:7202 us
  PIN_FAST_BENCHMARK: Time: get:488728 put:7101 us
  PIN_FAST_BENCHMARK: Time: get:487570 put:7327 us
  PIN_FAST_BENCHMARK: Time: get:489260 put:7027 us
  PIN_FAST_BENCHMARK: Time: get:488846 put:6866 us
  PIN_FAST_BENCHMARK: Time: get:488521 put:6745 us
  PIN_FAST_BENCHMARK: Time: get:489950 put:6459 us
  PIN_FAST_BENCHMARK: Time: get:489777 put:6617 us
  PIN_FAST_BENCHMARK: Time: get:488224 put:6591 us
  PIN_FAST_BENCHMARK: Time: get:488644 put:6477 us
  PIN_FAST_BENCHMARK: Time: get:488754 put:6711 us
  PIN_FAST_BENCHMARK: Time: get:488875 put:6743 us
  PIN_FAST_BENCHMARK: Time: get:489290 put:6657 us
  PIN_FAST_BENCHMARK: Time: get:490264 put:6684 us
  PIN_FAST_BENCHMARK: Time: get:489631 put:6737 us
  PIN_FAST_BENCHMARK: Time: get:488434 put:6655 us
  PIN_FAST_BENCHMARK: Time: get:492213 put:6297 us
  PIN_FAST_BENCHMARK: Time: get:491124 put:6173 us

After the whole series applied (new fixed kernel):

  $ sudo chrt -f 1 ./gup_test -a  -m 512 -j 40
  PIN_FAST_BENCHMARK: Time: get:82038 put:7041 us
  PIN_FAST_BENCHMARK: Time: get:82144 put:6817 us
  PIN_FAST_BENCHMARK: Time: get:83417 put:6674 us
  PIN_FAST_BENCHMARK: Time: get:82540 put:6594 us
  PIN_FAST_BENCHMARK: Time: get:83214 put:6681 us
  PIN_FAST_BENCHMARK: Time: get:83444 put:6889 us
  PIN_FAST_BENCHMARK: Time: get:83194 put:7499 us
  PIN_FAST_BENCHMARK: Time: get:84876 put:7369 us
  PIN_FAST_BENCHMARK: Time: get:86092 put:10289 us
  PIN_FAST_BENCHMARK: Time: get:86153 put:10415 us
  PIN_FAST_BENCHMARK: Time: get:85026 put:7751 us
  PIN_FAST_BENCHMARK: Time: get:85458 put:7944 us
  PIN_FAST_BENCHMARK: Time: get:85735 put:8154 us
  PIN_FAST_BENCHMARK: Time: get:85851 put:8299 us
  PIN_FAST_BENCHMARK: Time: get:86323 put:9617 us
  PIN_FAST_BENCHMARK: Time: get:86288 put:10496 us
  PIN_FAST_BENCHMARK: Time: get:87697 put:9346 us
  PIN_FAST_BENCHMARK: Time: get:87980 put:8382 us
  PIN_FAST_BENCHMARK: Time: get:88719 put:8400 us
  PIN_FAST_BENCHMARK: Time: get:87616 put:8588 us
  PIN_FAST_BENCHMARK: Time: get:86730 put:9563 us
  PIN_FAST_BENCHMARK: Time: get:88167 put:8673 us
  PIN_FAST_BENCHMARK: Time: get:86844 put:9777 us
  PIN_FAST_BENCHMARK: Time: get:88068 put:11774 us
  PIN_FAST_BENCHMARK: Time: get:86170 put:15676 us
  PIN_FAST_BENCHMARK: Time: get:87967 put:12827 us
  PIN_FAST_BENCHMARK: Time: get:95773 put:7652 us
  PIN_FAST_BENCHMARK: Time: get:87734 put:13650 us
  PIN_FAST_BENCHMARK: Time: get:89833 put:14237 us
  PIN_FAST_BENCHMARK: Time: get:96186 put:8029 us
  PIN_FAST_BENCHMARK: Time: get:95532 put:8886 us
  PIN_FAST_BENCHMARK: Time: get:95351 put:5826 us
  PIN_FAST_BENCHMARK: Time: get:96401 put:8407 us
  PIN_FAST_BENCHMARK: Time: get:96473 put:8287 us
  PIN_FAST_BENCHMARK: Time: get:97177 put:8430 us
  PIN_FAST_BENCHMARK: Time: get:98120 put:5263 us
  PIN_FAST_BENCHMARK: Time: get:96271 put:7757 us
  PIN_FAST_BENCHMARK: Time: get:99628 put:10467 us
  PIN_FAST_BENCHMARK: Time: get:99344 put:10045 us
  PIN_FAST_BENCHMARK: Time: get:94212 put:15485 us

Summary:

  Old kernel: 477729.97 (+-3.79%)
  New kernel:  89144.65 (+-11.76%)

This patch (of 3):

Add a new parameter "-j N" to support concurrent gup test.

Link: https://lkml.kernel.org/r/20210507150553.208763-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20210507150553.208763-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Kirill Shutemov <kirill@shutemov.name>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:48 -07:00
Pavel Tatashin e44605a8b1 selftests/vm: gup_test: test faulting in kernel, and verify pinnable pages
When pages are pinned they can be faulted in userland and migrated, and
they can be faulted right in kernel without migration.

In either case, the pinned pages must end-up being pinnable (not
movable).

Add a new test to gup_test, to help verify that the gup/pup
(get_user_pages() / pin_user_pages()) behavior with respect to pinnable
and movable pages is reasonable and correct.  Specifically, provide a
way to:

1) Verify that only "pinnable" pages are pinned.  This is checked
   automatically for you.

2) Verify that gup/pup performance is reasonable.  This requires
   comparing benchmarks between doing gup/pup on pages that have been
   pre-faulted in from user space, vs.  doing gup/pup on pages that are
   not faulted in until gup/pup time (via FOLL_TOUCH).  This decision is
   controlled with the new -z command line option.

Link: https://lkml.kernel.org/r/20210215161349.246722-15-pasha.tatashin@soleen.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tyler Hicks <tyhicks@linux.microsoft.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>
2021-05-05 11:27:26 -07:00
Pavel Tatashin 79dbf135e2 selftests/vm: gup_test: fix test flag
In gup_test both gup_flags and test_flags use the same flags field.
This is broken.

Farther, in the actual gup_test.c all the passed gup_flags are erased
and unconditionally replaced with FOLL_WRITE.

Which means that test_flags are ignored, and code like this always
performs pin dump test:

155  			if (gup->flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN)
156  				nr = pin_user_pages(addr, nr, gup->flags,
157  						    pages + i, NULL);
158  			else
159  				nr = get_user_pages(addr, nr, gup->flags,
160  						    pages + i, NULL);
161  			break;

Add a new test_flags field, to allow raw gup_flags to work.  Add a new
subcommand for DUMP_USER_PAGES_TEST to specify that pin test should be
performed.

Remove unconditional overwriting of gup_flags via FOLL_WRITE.  But,
preserve the previous behaviour where FOLL_WRITE was the default flag,
and add a new option "-W" to unset FOLL_WRITE.

Rename flags with gup_flags.

With the fix, dump works like this:

  root@virtme:/# gup_test  -c
  ---- page #0, starting from user virt addr: 0x7f8acb9e4000
  page:00000000d3d2ee27 refcount:2 mapcount:1 mapping:0000000000000000
  index:0x0 pfn:0x100bcf
  anon flags: 0x300000000080016(referenced|uptodate|lru|swapbacked)
  raw: 0300000000080016 ffffd0e204021608 ffffd0e208df2e88 ffff8ea04243ec61
  raw: 0000000000000000 0000000000000000 0000000200000000 0000000000000000
  page dumped because: gup_test: dump_pages() test
  DUMP_USER_PAGES_TEST: done

  root@virtme:/# gup_test  -c -p
  ---- page #0, starting from user virt addr: 0x7fd19701b000
  page:00000000baed3c7d refcount:1025 mapcount:1 mapping:0000000000000000
  index:0x0 pfn:0x108008
  anon flags: 0x300000000080014(uptodate|lru|swapbacked)
  raw: 0300000000080014 ffffd0e204200188 ffffd0e205e09088 ffff8ea04243ee71
  raw: 0000000000000000 0000000000000000 0000040100000000 0000000000000000
  page dumped because: gup_test: dump_pages() test
  DUMP_USER_PAGES_TEST: done

Refcount shows the difference between pin vs no-pin case.
Also change type of nr from int to long, as it counts number of pages.

Link: https://lkml.kernel.org/r/20210215161349.246722-14-pasha.tatashin@soleen.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Tyler Hicks <tyhicks@linux.microsoft.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>
2021-05-05 11:27:26 -07:00
Axel Rasmussen f0fa943309 userfaultfd/selftests: add test exercising minor fault handling
Fix a dormant bug in userfaultfd_events_test(), where we did `return
faulting_process(0)` instead of `exit(faulting_process(0))`.  This
caused the forked process to keep running, trying to execute any further
test cases after the events test in parallel with the "real" process.

Add a simple test case which exercises minor faults.  In short, it does
the following:

1. "Sets up" an area (area_dst) and a second shared mapping to the same
   underlying pages (area_dst_alias).

2. Register one of these areas with userfaultfd, in minor fault mode.

3. Start a second thread to handle any minor faults.

4. Populate the underlying pages with the non-UFFD-registered side of
   the mapping. Basically, memset() each page with some arbitrary
   contents.

5. Then, using the UFFD-registered mapping, read all of the page
   contents, asserting that the contents match expectations (we expect
   the minor fault handling thread can modify the page contents before
   resolving the fault).

The minor fault handling thread, upon receiving an event, flips all the
bits (~) in that page, just to prove that it can modify it in some
arbitrary way.  Then it issues a UFFDIO_CONTINUE ioctl, to setup the
mapping and resolve the fault.  The reading thread should wake up and
see this modification.

Currently the minor fault test is only enabled in hugetlb_shared mode,
as this is the only configuration the kernel feature supports.

Link: https://lkml.kernel.org/r/20210301222728.176417-7-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Cc: Adam Ruprecht <ruprecht@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Cannon Matthews <cannonmatthews@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: "Michal Koutn" <mkoutny@suse.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shawn Anastasio <shawn@anastas.io>
Cc: Steven Price <steven.price@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05 11:27:23 -07:00
Zi Yan fbe37501b2 mm: huge_memory: debugfs for file-backed THP split
Further extend <debugfs>/split_huge_pages to accept
"<path>,<pgoff_start>,<pgoff_end>" for file-backed THP split tests since
tmpfs may have file backed by THP that mapped nowhere.

Update selftest program to test file-backed THP split too.

Link: https://lkml.kernel.org/r/20210331235309.332292-2-zi.yan@sent.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Suggested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mika Penttila <mika.penttila@nextfour.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05 11:27:21 -07:00
Zi Yan fa6c02315f mm: huge_memory: a new debugfs interface for splitting THP tests
We did not have a direct user interface of splitting the compound page
backing a THP and there is no need unless we want to expose the THP
implementation details to users.  Make <debugfs>/split_huge_pages accept a
new command to do that.

By writing "<pid>,<vaddr_start>,<vaddr_end>" to
<debugfs>/split_huge_pages, THPs within the given virtual address range
from the process with the given pid are split. It is used to test
split_huge_page function. In addition, a selftest program is added to
tools/testing/selftests/vm to utilize the interface by splitting
PMD THPs and PTE-mapped THPs.

This does not change the old behavior, i.e., writing 1 to the interface
to split all THPs in the system.

Link: https://lkml.kernel.org/r/20210331235309.332292-1-zi.yan@sent.com
Signed-off-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mika Penttila <mika.penttila@nextfour.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05 11:27:21 -07:00
Uladzislau Rezki (Sony) 7bc4ca3ea9 vm/test_vmalloc.sh: adapt for updated driver interface
A 'single_cpu_test' parameter is odd and it does not exist anymore.
Instead there was introduced a 'nr_threads' one.  If it is not set it
behaves as the former parameter.

That is why update a "stress mode" according to this change specifying
number of workers which are equal to number of CPUs.  Also update an
output of help message based on a new interface.

Link: https://lkml.kernel.org/r/20210402202237.20334-3-urezki@gmail.com
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Matthew Wilcox <willy@infradead.org>
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>
2021-04-30 11:20:40 -07:00
Brian Geffon 8593100444 selftests: add a MREMAP_DONTUNMAP selftest for shmem
This test extends the current mremap tests to validate that the
MREMAP_DONTUNMAP operation can be performed on shmem mappings.

Link: https://lkml.kernel.org/r/20210323182520.2712101-3-bgeffon@google.com
Signed-off-by: Brian Geffon <bgeffon@google.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: "Michael S . Tsirkin" <mst@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: "Kirill A . Shutemov" <kirill@shutemov.name>
Cc: Dmitry Safonov <dima@arista.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Alejandro Colomar <alx.manpages@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:39 -07:00
Rong Chen 19ec368cbc selftests/vm: fix out-of-tree build
When building out-of-tree, attempting to make target from $(OUTPUT) directory:

  make[1]: *** No rule to make target '$(OUTPUT)/protection_keys.c', needed by '$(OUTPUT)/protection_keys_32'.

Link: https://lkml.kernel.org/r/20210315094700.522753-1-rong.a.chen@intel.com
Signed-off-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-03-25 09:22:55 -07:00
Rong Chen d52db80084 selftests/vm: rename file run_vmtests to run_vmtests.sh
Commit c2aa8afc36 has renamed run_vmtests in Makefile, but the file
still uses the old name.

The kernel test robot reported the following issue:

  # selftests: vm: run_vmtests.sh
  # Warning: file run_vmtests.sh is missing!
  not ok 1 selftests: vm: run_vmtests.sh

Link: https://lkml.kernel.org/r/20210205085507.1479894-1-rong.a.chen@intel.com
Fixes: c2aa8afc36 (selftests/vm: rename run_vmtests --> run_vmtests.sh)
Signed-off-by: Rong Chen <rong.a.chen@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-02-09 17:26:44 -08:00
Harish 7cf22a1c88 selftests/vm: fix building protection keys test
Commit d8cbe8bfa7 ("tools/testing/selftests/vm: fix build error") tried
to include a ARCH check for powerpc, however ARCH is not defined in the
Makefile before including lib.mk.  This makes test building to skip on
both x86 and powerpc.

Fix the arch check by replacing it using machine type as it is already
defined and used in the test.

Link: https://lkml.kernel.org/r/20201215100402.257376-1-harish@linux.ibm.com
Fixes: d8cbe8bfa7 ("tools/testing/selftests/vm: fix build error")
Signed-off-by: Harish <harish@linux.ibm.com>
Reviewed-by: Sandipan Das <sandipan@linux.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-29 15:36:49 -08:00
Linus Torvalds 7194850efa linux-kselftest-next-5.11-rc1
This kselftest update for Linux 5.11-rc1 consists of:
 
 - Much needed gpio test Makefile cleanup to various problems with
   test dependencies and build errors from Michael Ellerman
 
 - Enabling vDSO test on non x86 platforms from Vincenzo Frascino
 
 - Fix intel_pstate to replace deprecated ftime() usages with
   clock_gettime() from Tommi Rantala
 
 - cgroup test build fix on older releases from Sachin Sant
 
 - A couple of spelling mistake fixes
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Merge tag 'linux-kselftest-next-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull Kselftest updates from Shuah Khan:

 - Much needed gpio test Makefile cleanup to various problems with test
   dependencies and build errors from Michael Ellerman

 - Enabling vDSO test on non x86 platforms from Vincenzo Frascino

 - Fix intel_pstate to replace deprecated ftime() usages with
   clock_gettime() from Tommi Rantala

 - cgroup test build fix on older releases from Sachin Sant

 - A couple of spelling mistake fixes

* tag 'linux-kselftest-next-5.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests/cgroup: Fix build on older distros
  selftests/run_kselftest.sh: fix dry-run typo
  tool: selftests: fix spelling typo of 'writting'
  selftests/memfd: Fix implicit declaration warnings
  selftests: intel_pstate: ftime() is deprecated
  selftests/gpio: Add to CLEAN rule rather than overriding
  selftests/gpio: Fix build when source tree is read only
  selftests/gpio: Move include of lib.mk up
  selftests/gpio: Use TEST_GEN_PROGS_EXTENDED
  kselftest: Extend vdso correctness test to clock_gettime64
  kselftest: Move test_vdso to the vDSO test suite
  kselftest: Extend vDSO selftest to clock_getres
  kselftest: Extend vDSO selftest
  kselftest: Enable vDSO test on non x86 platforms
2020-12-16 00:17:58 -08:00
Peter Xu d9f411bacf userfaultfd/selftests: hint the test runner on required privilege
Now userfaultfd test program requires either root or ptrace privilege due
to the signal/event tests.  When UFFDIO_API failed, hint the test runner
about this fact verbosely.

Link: https://lkml.kernel.org/r/20201208024709.7701-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Peter Xu 1e17a24edf userfaultfd/selftests: fix retval check for userfaultfd_open()
userfaultfd_open() returns 1 for errors rather than negatives.  Fix it on
all the callers so when UFFDIO_API failed the test will bail out.

Link: https://lkml.kernel.org/r/20201208024709.7701-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Peter Xu 164c50be28 userfaultfd/selftests: always dump something in modes
Patch series "userfaultfd: selftests: Small fixes".

Some very trivial fixes that I kept locally to userfaultfd selftest
program.

This patch (of 3):

BOUNCE_POLL is a special bit that if cleared it means "READ" instead.
Dump that too otherwise we'll see tests with empty modes.

Link: https://lkml.kernel.org/r/20201208024709.7701-1-peterx@redhat.com
Link: https://lkml.kernel.org/r/20201208024709.7701-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Axel Rasmussen 77f962e7ae userfaultfd: selftests: make __{s,u}64 format specifiers portable
On certain platforms (powerpcle is the one on which I ran into this),
"%Ld" and "%Lu" are unsuitable for printing __s64 and __u64, respectively,
resulting in build warnings.  Cast to {u,}int64_t, and use the PRI{d,u}64
macros defined in inttypes.h to print them.  This ought to be portable to
all platforms.

Splitting this off into a separate macro lets us remove some lines, and
get rid of some (I would argue) stylistically odd cases where we joined
printf() and exit() into a single statement with a ,.

Finally, this also fixes a "missing braces around initializer" warning
when we initialize prms in wp_range().

[axelrasmussen@google.com: v2]
  Link: https://lkml.kernel.org/r/20201203180244.1811601-1-axelrasmussen@google.com

Link: https://lkml.kernel.org/r/20201202211542.1121189-1-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Acked-by: Peter Xu <peterx@redhat.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Joe Perches <joe@perches.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: David Alan Gilbert <dgilbert@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:46 -08:00
Kalesh Singh 7df666253f kselftests: vm: add mremap tests
Patch series "Speed up mremap on large regions", v4.

mremap time can be optimized by moving entries at the PMD/PUD level if the
source and destination addresses are PMD/PUD-aligned and PMD/PUD-sized.
Enable moving at the PMD and PUD levels on arm64 and x86.  Other
architectures where this type of move is supported and known to be safe
can also opt-in to these optimizations by enabling HAVE_MOVE_PMD and
HAVE_MOVE_PUD.

Observed Performance Improvements for remapping a PUD-aligned 1GB-sized
region on x86 and arm64:

    - HAVE_MOVE_PMD is already enabled on x86 : N/A
    - Enabling HAVE_MOVE_PUD on x86   : ~13x speed up

    - Enabling HAVE_MOVE_PMD on arm64 : ~ 8x speed up
    - Enabling HAVE_MOVE_PUD on arm64 : ~19x speed up

          Altogether, HAVE_MOVE_PMD and HAVE_MOVE_PUD
          give a total of ~150x speed up on arm64.

This patch (of 4):

Test mremap on regions of various sizes and alignments and validate data
after remapping.  Also provide total time for remapping the region which
is useful for performance comparison of the mremap optimizations that move
pages at the PMD/PUD levels if HAVE_MOVE_PMD and/or HAVE_MOVE_PUD are
enabled.

Link: https://lkml.kernel.org/r/20201014005320.2233162-1-kaleshsingh@google.com
Link: https://lkml.kernel.org/r/20201014005320.2233162-2-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Hassan Naveed <hnaveed@wavecomp.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Gavin Shan <gshan@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Steven Price <steven.price@arm.com>
Cc: Jia He <justin.he@arm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sandipan Das <sandipan@linux.ibm.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:40 -08:00
John Hubbard a26c4c6299 selftests/vm: 2x speedup for run_vmtests.sh
Each invocation of userfaultfd for "anon" and "shmem" was taking about
6.5 sec to run, contributing to an overall run time of about 22 sec for
run_vmtests.sh.

Reduce the size and bounce input values to the userfaultfd invocation
within run_vmtests.sh, enough to get each invocation down to about 1.0
sec. This should still provide a reasonable smoke test, while staying
within a nominal time budget of around 1 second or so per test. And this
brings the overall running time of run_vmtests.sh down to 11 second.

Link: https://lkml.kernel.org/r/20201026064021.3545418-10-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:38 -08:00
John Hubbard f3a45709d2 selftests/vm: hmm-tests: remove the libhugetlbfs dependency
HMM selftests are incredibly useful, but they are only effective if people
actually build and run them.  All the other tests in selftests/vm can be
built with very standard, always-available libraries: libpthread, librt.
The hmm-tests.c program, on the other hand, requires something that is
(much) less readily available: libhugetlbfs.  And so the build will
typically fail for many developers.

A simple attempt to install libhugetlbfs will also run into complications
on some common distros these days: Fedora and Arch Linux (yes, Arch AUR
has it, but that's fragile, as always with AUR).  The library is not
maintained actively enough at the moment, for distros to deal with it.  I
had to build it from source, for Fedora, and that didn't go too smoothly
either.

It turns out that, out of 21 tests in hmm-tests.c, only 2 actually require
functionality from libhugetlbfs.  Therefore, if libhugetlbfs is missing,
simply ifdef those two tests out and allow the developer to at least have
the other 19 tests, if they don't want to pause to work through the above
issues.  Also issue a warning, so that it's clear that there is an
imperfection in the build.

In order to do that, a tiny shell script (check_config.sh) runs a quick
compile (not link, that's too prone to false failures with library paths),
and basically, if the compiler doesn't find hugetlbfs.h in its standard
locations, then the script concludes that libhugetlbfs is not available.
The output is in two files, one for inclusion in hmm-test.c
(local_config.h), and one for inclusion in the Makefile (local_config.mk).

Link: https://lkml.kernel.org/r/20201026064021.3545418-9-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:38 -08:00