mm/hmm/test: add self tests for HMM

This series adds basic self tests for HMM and are intended for Jason Gunthorpe's rdma tree since I believe he is planning to make some HMM related changes that this can help test.

Changes v8 -> v9:
Rebased to linux-5.7.0-rc1.
Moved include/uapi/linux/test_hmm.h to lib/test_hmm_uapi.h Added calls to release_mem_region() to free device private addresses Applied Jason's suggested changes for v8.
Added a check for no VMA read access before migrating to device private
memory.

Changes v7 -> v8:
Rebased to Jason's rdma/hmm tree, plus Jason's 6 patch series
"Small hmm_range_fault() cleanups".
Applied a number of changes from Jason's comments.

Changes v6 -> v7:
Rebased to linux-5.6.0-rc6
Reverted back to just using mmu_interval_notifier_insert() and making
this series only introduce HMM self tests.

Changes v5 -> v6:
Rebased to linux-5.5.0-rc6
Refactored mmu interval notifier patches Converted nouveau to use the new mmu interval notifier API

Changes v4 -> v5:
Added mmu interval notifier insert/remove/update callable from the
invalidate() callback
Updated HMM tests to use the new core interval notifier API

Changes v1 -> v4:
https://lore.kernel.org/linux-mm/[email protected]

Ralph Campbell (3):
mm/hmm/test: add selftest driver for HMM
mm/hmm/test: add selftests for HMM
MAINTAINERS: add HMM selftests

 MAINTAINERS                            |    3 +
 lib/Kconfig.debug                      |   13 +
 lib/Makefile                           |    1 +
 lib/test_hmm.c                         | 1175 ++++++++++++++++++++
 lib/test_hmm_uapi.h                    |   59 +
 tools/testing/selftests/vm/.gitignore  |    1 +
 tools/testing/selftests/vm/Makefile    |    3 +
 tools/testing/selftests/vm/config      |    2 +
 tools/testing/selftests/vm/hmm-tests.c | 1359 ++++++++++++++++++++++++
 tools/testing/selftests/vm/run_vmtests |   16 +
 tools/testing/selftests/vm/test_hmm.sh |   97 ++
 11 files changed, 2729 insertions(+)
 create mode 100644 lib/test_hmm.c
 create mode 100644 lib/test_hmm_uapi.h
 create mode 100644 tools/testing/selftests/vm/hmm-tests.c
 create mode 100755 tools/testing/selftests/vm/test_hmm.sh

2.25.2

This driver is for testing device private memory migration and devices which use hmm_range_fault() to access system memory via device page tables.

---
 lib/Kconfig.debug   |   13 +
 lib/Makefile        |    1 +
 lib/test_hmm.c      | 1175 +++++++++++++++++++++++++++++++++++++++++++
 lib/test_hmm_uapi.h |   59 +++
 4 files changed, 1248 insertions(+)
 create mode 100644 lib/test_hmm.c
 create mode 100644 lib/test_hmm_uapi.h

index 50c1f5f08e6f..ac7751e640e9 100644
@@ -2199,6 +2199,19 @@ config TEST_MEMINIT
 
 	  If unsure, say N.
 
+config TEST_HMM
+	tristate "Test HMM (Heterogeneous Memory Management)"
+	depends on TRANSPARENT_HUGEPAGE
+	select DEVICE_PRIVATE
+	select HMM_MIRROR
+	select MMU_NOTIFIER
+	help
+	  This is a pseudo device driver solely for testing HMM.
+	  Say M here if you want to build the HMM test module.
+	  Doing so will allow you to run tools/testing/selftest/vm/hmm-tests.
+
+	  If unsure, say N.
+
 endif # RUNTIME_TESTING_MENU
 
 config MEMTEST

index 685aee60de1d..93d8ad358b44 100644
@@ -92,6 +92,7 @@ obj-$(CONFIG_TEST_STACKINIT) += test_stackinit.o
 obj-$(CONFIG_TEST_BLACKHOLE_DEV) += test_blackhole_dev.o
 obj-$(CONFIG_TEST_MEMINIT) += test_meminit.o
 obj-$(CONFIG_TEST_LOCKUP) += test_lockup.o
+obj-$(CONFIG_TEST_HMM) += test_hmm.o
 
 obj-$(CONFIG_TEST_LIVEPATCH) += livepatch/
 

2.25.2

Add some basic stand alone self tests for HMM.
The test program and shell scripts use the test_hmm.ko driver to exercise HMM functionality in the kernel.

---
 tools/testing/selftests/vm/.gitignore  |    1 +
 tools/testing/selftests/vm/Makefile    |    3 +
 tools/testing/selftests/vm/config      |    2 +
 tools/testing/selftests/vm/hmm-tests.c | 1359 ++++++++++++++++++++++++
 tools/testing/selftests/vm/run_vmtests |   16 +
 tools/testing/selftests/vm/test_hmm.sh |   97 ++
 6 files changed, 1478 insertions(+)
 create mode 100644 tools/testing/selftests/vm/hmm-tests.c
 create mode 100755 tools/testing/selftests/vm/test_hmm.sh

index 0edb6d900e8d..f25208eca5ff 100644
@@ -16,3 +16,4 @@ gup_benchmark
 va_128TBswitch
 map_fixed_noreplace
 write_to_hugetlbfs
+hmm-tests

index d31db052dff6..4dd6689157bc 100644
@@ -7,6 +7,7 @@ CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)
 LDLIBS = -lrt
 TEST_GEN_FILES = compaction_test
 TEST_GEN_FILES += gup_benchmark
+TEST_GEN_FILES += hmm-tests
 TEST_GEN_FILES += hugepage-mmap
 TEST_GEN_FILES += hugepage-shm
 TEST_GEN_FILES += map_hugetlb

@@ -33,6 +34,8 @@ TEST_FILES := test_vmalloc.sh
 KSFT_KHDR_INSTALL := 1
 include ../lib.mk
 
+$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs -lpthread
+
 $(OUTPUT)/userfaultfd: LDLIBS += -lpthread
 
 $(OUTPUT)/mlock-random-test: LDLIBS += -lcap

index 93b90a9b1eeb..3ba674b64fa9 100644
@@ -1,3 +1,5 @@
 CONFIG_SYSVIPC=y
 CONFIG_USERFAULTFD=y
 CONFIG_TEST_VMALLOC=m
+CONFIG_DEVICE_PRIVATE=y
+CONFIG_TEST_HMM=m

index 665009ebfba4..4f0e272285d9 100755
@@ -307,4 +307,20 @@ else
 	echo "[FAIL]"
 	exitcode=1
 fi
+
+echo "running HMM smoke test"
+echo "------------------------------------"
+./test_hmm.sh smoke
+ret_val=$?
+
+if [ $ret_val -eq 0 ]; then
+	echo "[PASS]"
+elif [ $ret_val -eq $ksft_skip ]; then
+	echo "[SKIP]"
+	exitcode=$ksft_skip
+else
+	echo "[FAIL]"
+	exitcode=1
+fi
+
 exit $exitcode

2.25.2

Add files for HMM selftests.

---
 MAINTAINERS | 3 +++
 1 file changed, 3 insertions(+)

index e64e5db31497..072921b7bae2 100644
@@ -7729,6 +7729,9 @@ S:	Maintained
 F:	Documentation/vm/hmm.rst
 F:	include/linux/hmm*
 F:	mm/hmm*
+F:	include/uapi/linux/test_hmm*
+F:	lib/test_hmm*
+F:	tools/testing/selftests/vm/*hmm*
 
 HOST AP DRIVER
 M:	Jouni Malinen <[email protected]>

2.25.2

checkpatch rule for this, please ;)

Already sent a few days ago to you ;)

https://lore.kernel.org/lkml/[email protected]/

And somehow already in -mm too, at least by the email you sent me:

The patch titled
Subject: checkpatch: additional MAINTAINER section entry ordering checks
has been added to the -mm tree. Its filename is
checkpatch-additional-maintainer-section-entry-ordering-checks.patch

This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/checkpatch-additional-maintainer-section-entry-ordering-checks.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/checkpatch-additional-maintainer-section-entry-ordering-checks.patch

No problem. Will fix in the next posting.
Thanks.

Thank you. I'll fix this in the next posting.