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@ 2020-10-17 23:13 Andrew Morton
  2020-10-17 23:13 ` [patch 01/40] ia64: fix build error with !COREDUMP Andrew Morton
                   ` (39 more replies)
  0 siblings, 40 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: Linus Torvalds; +Cc: mm-commits, linux-mm


40 patches, based on 9d9af1007bc08971953ae915d88dc9bb21344b53.

Subsystems affected by this patch series:

  ia64
  mm/memcg
  mm/migration
  mm/pagemap
  mm/gup
  mm/madvise
  mm/vmalloc
  misc

Subsystem: ia64

    Krzysztof Kozlowski <krzk@kernel.org>:
      ia64: fix build error with !COREDUMP

Subsystem: mm/memcg

    Roman Gushchin <guro@fb.com>:
      mm, memcg: rework remote charging API to support nesting
    Patch series "mm: kmem: kernel memory accounting in an interrupt context":
      mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current()
      mm: kmem: remove redundant checks from get_obj_cgroup_from_current()
      mm: kmem: prepare remote memcg charging infra for interrupt contexts
      mm: kmem: enable kernel memcg accounting from interrupt contexts

Subsystem: mm/migration

    Joonsoo Kim <iamjoonsoo.kim@lge.com>:
      mm/memory-failure: remove a wrapper for alloc_migration_target()
      mm/memory_hotplug: remove a wrapper for alloc_migration_target()

    Miaohe Lin <linmiaohe@huawei.com>:
      mm/migrate: avoid possible unnecessary process right check in kernel_move_pages()

Subsystem: mm/pagemap

    "Liam R. Howlett" <Liam.Howlett@Oracle.com>:
      mm/mmap: add inline vma_next() for readability of mmap code
      mm/mmap: add inline munmap_vma_range() for code readability

Subsystem: mm/gup

    Jann Horn <jannh@google.com>:
      mm/gup_benchmark: take the mmap lock around GUP
      binfmt_elf: take the mmap lock around find_extend_vma()
      mm/gup: assert that the mmap lock is held in __get_user_pages()

    John Hubbard <jhubbard@nvidia.com>:
    Patch series "selftests/vm: gup_test, hmm-tests, assorted improvements", v2:
      mm/gup_benchmark: rename to mm/gup_test
      selftests/vm: use a common gup_test.h
      selftests/vm: rename run_vmtests --> run_vmtests.sh
      selftests/vm: minor cleanup: Makefile and gup_test.c
      selftests/vm: only some gup_test items are really benchmarks
      selftests/vm: gup_test: introduce the dump_pages() sub-test
      selftests/vm: run_vmtests.sh: update and clean up gup_test invocation
      selftests/vm: hmm-tests: remove the libhugetlbfs dependency
      selftests/vm: 10x speedup for hmm-tests

Subsystem: mm/madvise

    Minchan Kim <minchan@kernel.org>:
    Patch series "introduce memory hinting API for external process", v9:
      mm/madvise: pass mm to do_madvise
      pid: move pidfd_get_pid() to pid.c
      mm/madvise: introduce process_madvise() syscall: an external memory hinting API

Subsystem: mm/vmalloc

    "Matthew Wilcox (Oracle)" <willy@infradead.org>:
    Patch series "remove alloc_vm_area", v4:
      mm: update the documentation for vfree

    Christoph Hellwig <hch@lst.de>:
      mm: add a VM_MAP_PUT_PAGES flag for vmap
      mm: add a vmap_pfn function
      mm: allow a NULL fn callback in apply_to_page_range
      zsmalloc: switch from alloc_vm_area to get_vm_area
      drm/i915: use vmap in shmem_pin_map
      drm/i915: stop using kmap in i915_gem_object_map
      drm/i915: use vmap in i915_gem_object_map
      xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv
      x86/xen: open code alloc_vm_area in arch_gnttab_valloc
      mm: remove alloc_vm_area
    Patch series "two small vmalloc cleanups":
      mm: cleanup the gfp_mask handling in __vmalloc_area_node
      mm: remove the filename in the top of file comment in vmalloc.c

Subsystem: misc

    Tian Tao <tiantao6@hisilicon.com>:
      mm: remove duplicate include statement in mmu.c

 Documentation/core-api/pin_user_pages.rst   |    8 
 arch/alpha/kernel/syscalls/syscall.tbl      |    1 
 arch/arm/mm/mmu.c                           |    1 
 arch/arm/tools/syscall.tbl                  |    1 
 arch/arm64/include/asm/unistd.h             |    2 
 arch/arm64/include/asm/unistd32.h           |    2 
 arch/ia64/kernel/Makefile                   |    2 
 arch/ia64/kernel/syscalls/syscall.tbl       |    1 
 arch/m68k/kernel/syscalls/syscall.tbl       |    1 
 arch/microblaze/kernel/syscalls/syscall.tbl |    1 
 arch/mips/kernel/syscalls/syscall_n32.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_n64.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_o32.tbl   |    1 
 arch/parisc/kernel/syscalls/syscall.tbl     |    1 
 arch/powerpc/kernel/syscalls/syscall.tbl    |    1 
 arch/s390/configs/debug_defconfig           |    2 
 arch/s390/configs/defconfig                 |    2 
 arch/s390/kernel/syscalls/syscall.tbl       |    1 
 arch/sh/kernel/syscalls/syscall.tbl         |    1 
 arch/sparc/kernel/syscalls/syscall.tbl      |    1 
 arch/x86/entry/syscalls/syscall_32.tbl      |    1 
 arch/x86/entry/syscalls/syscall_64.tbl      |    1 
 arch/x86/xen/grant-table.c                  |   27 +-
 arch/xtensa/kernel/syscalls/syscall.tbl     |    1 
 drivers/gpu/drm/i915/Kconfig                |    1 
 drivers/gpu/drm/i915/gem/i915_gem_pages.c   |  136 ++++------
 drivers/gpu/drm/i915/gt/shmem_utils.c       |   78 +-----
 drivers/xen/xenbus/xenbus_client.c          |   30 +-
 fs/binfmt_elf.c                             |    3 
 fs/buffer.c                                 |    6 
 fs/io_uring.c                               |    2 
 fs/notify/fanotify/fanotify.c               |    5 
 fs/notify/inotify/inotify_fsnotify.c        |    5 
 include/linux/memcontrol.h                  |   12 
 include/linux/mm.h                          |    2 
 include/linux/pid.h                         |    1 
 include/linux/sched/mm.h                    |   43 +--
 include/linux/syscalls.h                    |    2 
 include/linux/vmalloc.h                     |    7 
 include/uapi/asm-generic/unistd.h           |    4 
 kernel/exit.c                               |   19 -
 kernel/pid.c                                |   19 +
 kernel/sys_ni.c                             |    1 
 mm/Kconfig                                  |   24 +
 mm/Makefile                                 |    2 
 mm/gup.c                                    |    2 
 mm/gup_benchmark.c                          |  225 ------------------
 mm/gup_test.c                               |  295 +++++++++++++++++++++--
 mm/gup_test.h                               |   40 ++-
 mm/madvise.c                                |  125 ++++++++--
 mm/memcontrol.c                             |   83 ++++--
 mm/memory-failure.c                         |   18 -
 mm/memory.c                                 |   16 -
 mm/memory_hotplug.c                         |   46 +--
 mm/migrate.c                                |   71 +++--
 mm/mmap.c                                   |   74 ++++-
 mm/nommu.c                                  |    7 
 mm/percpu.c                                 |    3 
 mm/slab.h                                   |    3 
 mm/vmalloc.c                                |  147 +++++------
 mm/zsmalloc.c                               |   10 
 tools/testing/selftests/vm/.gitignore       |    3 
 tools/testing/selftests/vm/Makefile         |   40 ++-
 tools/testing/selftests/vm/check_config.sh  |   31 ++
 tools/testing/selftests/vm/config           |    2 
 tools/testing/selftests/vm/gup_benchmark.c  |  143 -----------
 tools/testing/selftests/vm/gup_test.c       |  260 ++++++++++++++++++--
 tools/testing/selftests/vm/hmm-tests.c      |   12 
 tools/testing/selftests/vm/run_vmtests      |  334 --------------------------
 tools/testing/selftests/vm/run_vmtests.sh   |  350 +++++++++++++++++++++++++++-
 70 files changed, 1580 insertions(+), 1224 deletions(-)



^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 01/40] ia64: fix build error with !COREDUMP
  2020-10-17 23:13 incoming Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 02/40] mm, memcg: rework remote charging API to support nesting Andrew Morton
                   ` (38 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, fenghua.yu, krzk, linux-mm, lkp, mm-commits, stable,
	tony.luck, torvalds

From: Krzysztof Kozlowski <krzk@kernel.org>
Subject: ia64: fix build error with !COREDUMP

Fix linkage error when CONFIG_BINFMT_ELF is selected but CONFIG_COREDUMP
is not:

    ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_phdrs':
    elfcore.c:(.text+0x172): undefined reference to `dump_emit'
    ia64-linux-ld: arch/ia64/kernel/elfcore.o: in function `elf_core_write_extra_data':
    elfcore.c:(.text+0x2b2): undefined reference to `dump_emit'

Link: https://lkml.kernel.org/r/20200819064146.12529-1-krzk@kernel.org
Fixes: 1fcccbac89f5 ("elf coredump: replace ELF_CORE_EXTRA_* macros by functions")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/ia64/kernel/Makefile |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/ia64/kernel/Makefile~ia64-fix-build-error-with-coredump
+++ a/arch/ia64/kernel/Makefile
@@ -40,7 +40,7 @@ obj-y				+= esi_stub.o	# must be in kern
 endif
 obj-$(CONFIG_INTEL_IOMMU)	+= pci-dma.o
 
-obj-$(CONFIG_BINFMT_ELF)	+= elfcore.o
+obj-$(CONFIG_ELF_CORE)		+= elfcore.o
 
 # fp_emulate() expects f2-f5,f16-f31 to contain the user-level state.
 CFLAGS_traps.o  += -mfixed-range=f2-f5,f16-f31
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 02/40] mm, memcg: rework remote charging API to support nesting
  2020-10-17 23:13 incoming Andrew Morton
  2020-10-17 23:13 ` [patch 01/40] ia64: fix build error with !COREDUMP Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 03/40] mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current() Andrew Morton
                   ` (37 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, dschatzberg, guro, hannes, linux-mm, mm-commits, shakeelb,
	torvalds

From: Roman Gushchin <guro@fb.com>
Subject: mm, memcg: rework remote charging API to support nesting

Currently the remote memcg charging API consists of two functions:
memalloc_use_memcg() and memalloc_unuse_memcg(), which set and clear the
memcg value, which overwrites the memcg of the current task.

  memalloc_use_memcg(target_memcg);
  <...>
  memalloc_unuse_memcg();

It works perfectly for allocations performed from a normal context,
however an attempt to call it from an interrupt context or just nest two
remote charging blocks will lead to an incorrect accounting.  On exit from
the inner block the active memcg will be cleared instead of being
restored.

  memalloc_use_memcg(target_memcg);

  memalloc_use_memcg(target_memcg_2);
    <...>
    memalloc_unuse_memcg();

    Error: allocation here are charged to the memcg of the current
    process instead of target_memcg.

  memalloc_unuse_memcg();

This patch extends the remote charging API by switching to a single
function: struct mem_cgroup *set_active_memcg(struct mem_cgroup *memcg),
which sets the new value and returns the old one.  So a remote charging
block will look like:

  old_memcg = set_active_memcg(target_memcg);
  <...>
  set_active_memcg(old_memcg);

This patch is heavily based on the patch by Johannes Weiner, which can be
found here: https://lkml.org/lkml/2020/5/28/806 .

Link: https://lkml.kernel.org/r/20200821212056.3769116-1-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Dan Schatzberg <dschatzberg@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/buffer.c                          |    6 ++---
 fs/notify/fanotify/fanotify.c        |    5 ++--
 fs/notify/inotify/inotify_fsnotify.c |    5 ++--
 include/linux/sched/mm.h             |   30 ++++++++-----------------
 mm/memcontrol.c                      |    6 ++---
 5 files changed, 22 insertions(+), 30 deletions(-)

--- a/fs/buffer.c~mm-rework-remote-memcg-charging-api-to-support-nesting
+++ a/fs/buffer.c
@@ -842,13 +842,13 @@ struct buffer_head *alloc_page_buffers(s
 	struct buffer_head *bh, *head;
 	gfp_t gfp = GFP_NOFS | __GFP_ACCOUNT;
 	long offset;
-	struct mem_cgroup *memcg;
+	struct mem_cgroup *memcg, *old_memcg;
 
 	if (retry)
 		gfp |= __GFP_NOFAIL;
 
 	memcg = get_mem_cgroup_from_page(page);
-	memalloc_use_memcg(memcg);
+	old_memcg = set_active_memcg(memcg);
 
 	head = NULL;
 	offset = PAGE_SIZE;
@@ -867,7 +867,7 @@ struct buffer_head *alloc_page_buffers(s
 		set_bh_page(bh, page, offset);
 	}
 out:
-	memalloc_unuse_memcg();
+	set_active_memcg(old_memcg);
 	mem_cgroup_put(memcg);
 	return head;
 /*
--- a/fs/notify/fanotify/fanotify.c~mm-rework-remote-memcg-charging-api-to-support-nesting
+++ a/fs/notify/fanotify/fanotify.c
@@ -531,6 +531,7 @@ static struct fanotify_event *fanotify_a
 	struct inode *dirid = fanotify_dfid_inode(mask, data, data_type, dir);
 	const struct path *path = fsnotify_data_path(data, data_type);
 	unsigned int fid_mode = FAN_GROUP_FLAG(group, FANOTIFY_FID_BITS);
+	struct mem_cgroup *old_memcg;
 	struct inode *child = NULL;
 	bool name_event = false;
 
@@ -580,7 +581,7 @@ static struct fanotify_event *fanotify_a
 		gfp |= __GFP_RETRY_MAYFAIL;
 
 	/* Whoever is interested in the event, pays for the allocation. */
-	memalloc_use_memcg(group->memcg);
+	old_memcg = set_active_memcg(group->memcg);
 
 	if (fanotify_is_perm_event(mask)) {
 		event = fanotify_alloc_perm_event(path, gfp);
@@ -608,7 +609,7 @@ static struct fanotify_event *fanotify_a
 		event->pid = get_pid(task_tgid(current));
 
 out:
-	memalloc_unuse_memcg();
+	set_active_memcg(old_memcg);
 	return event;
 }
 
--- a/fs/notify/inotify/inotify_fsnotify.c~mm-rework-remote-memcg-charging-api-to-support-nesting
+++ a/fs/notify/inotify/inotify_fsnotify.c
@@ -66,6 +66,7 @@ static int inotify_one_event(struct fsno
 	int ret;
 	int len = 0;
 	int alloc_len = sizeof(struct inotify_event_info);
+	struct mem_cgroup *old_memcg;
 
 	if ((inode_mark->mask & FS_EXCL_UNLINK) &&
 	    path && d_unlinked(path->dentry))
@@ -87,9 +88,9 @@ static int inotify_one_event(struct fsno
 	 * trigger OOM killer in the target monitoring memcg as it may have
 	 * security repercussion.
 	 */
-	memalloc_use_memcg(group->memcg);
+	old_memcg = set_active_memcg(group->memcg);
 	event = kmalloc(alloc_len, GFP_KERNEL_ACCOUNT | __GFP_RETRY_MAYFAIL);
-	memalloc_unuse_memcg();
+	set_active_memcg(old_memcg);
 
 	if (unlikely(!event)) {
 		/*
--- a/include/linux/sched/mm.h~mm-rework-remote-memcg-charging-api-to-support-nesting
+++ a/include/linux/sched/mm.h
@@ -280,38 +280,28 @@ static inline void memalloc_nocma_restor
 
 #ifdef CONFIG_MEMCG
 /**
- * memalloc_use_memcg - Starts the remote memcg charging scope.
+ * set_active_memcg - Starts the remote memcg charging scope.
  * @memcg: memcg to charge.
  *
  * This function marks the beginning of the remote memcg charging scope. All the
  * __GFP_ACCOUNT allocations till the end of the scope will be charged to the
  * given memcg.
  *
- * NOTE: This function is not nesting safe.
+ * NOTE: This function can nest. Users must save the return value and
+ * reset the previous value after their own charging scope is over.
  */
-static inline void memalloc_use_memcg(struct mem_cgroup *memcg)
+static inline struct mem_cgroup *
+set_active_memcg(struct mem_cgroup *memcg)
 {
-	WARN_ON_ONCE(current->active_memcg);
+	struct mem_cgroup *old = current->active_memcg;
 	current->active_memcg = memcg;
-}
-
-/**
- * memalloc_unuse_memcg - Ends the remote memcg charging scope.
- *
- * This function marks the end of the remote memcg charging scope started by
- * memalloc_use_memcg().
- */
-static inline void memalloc_unuse_memcg(void)
-{
-	current->active_memcg = NULL;
+	return old;
 }
 #else
-static inline void memalloc_use_memcg(struct mem_cgroup *memcg)
-{
-}
-
-static inline void memalloc_unuse_memcg(void)
+static inline struct mem_cgroup *
+set_active_memcg(struct mem_cgroup *memcg)
 {
+	return NULL;
 }
 #endif
 
--- a/mm/memcontrol.c~mm-rework-remote-memcg-charging-api-to-support-nesting
+++ a/mm/memcontrol.c
@@ -5290,12 +5290,12 @@ static struct cgroup_subsys_state * __re
 mem_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
 {
 	struct mem_cgroup *parent = mem_cgroup_from_css(parent_css);
-	struct mem_cgroup *memcg;
+	struct mem_cgroup *memcg, *old_memcg;
 	long error = -ENOMEM;
 
-	memalloc_use_memcg(parent);
+	old_memcg = set_active_memcg(parent);
 	memcg = mem_cgroup_alloc();
-	memalloc_unuse_memcg();
+	set_active_memcg(old_memcg);
 	if (IS_ERR(memcg))
 		return ERR_CAST(memcg);
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 03/40] mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current()
  2020-10-17 23:13 incoming Andrew Morton
  2020-10-17 23:13 ` [patch 01/40] ia64: fix build error with !COREDUMP Andrew Morton
  2020-10-17 23:13 ` [patch 02/40] mm, memcg: rework remote charging API to support nesting Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 04/40] mm: kmem: remove redundant checks from get_obj_cgroup_from_current() Andrew Morton
                   ` (36 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, guro, hannes, linux-mm, mhocko, mm-commits, shakeelb, torvalds

From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current()

Patch series "mm: kmem: kernel memory accounting in an interrupt context".

This patchset implements memcg-based memory accounting of allocations made
from an interrupt context.

Historically, such allocations were passed unaccounted mostly because
charging the memory cgroup of the current process wasn't an option.  Also
performance reasons were likely a reason too.

The remote charging API allows to temporarily overwrite the currently
active memory cgroup, so that all memory allocations are accounted towards
some specified memory cgroup instead of the memory cgroup of the current
process.

This patchset extends the remote charging API so that it can be used from
an interrupt context.  Then it removes the fence that prevented the
accounting of allocations made from an interrupt context.  It also
contains a couple of optimizations/code refactorings.

This patchset doesn't directly enable accounting for any specific
allocations, but prepares the code base for it.  The bpf memory accounting
will likely be the first user of it: a typical example is a bpf program
parsing an incoming network packet, which allocates an entry in hashmap
map to store some information.


This patch (of 4):

Currently memcg_kmem_bypass() is called before obtaining the current
memory/obj cgroup using get_mem/obj_cgroup_from_current().  Moving
memcg_kmem_bypass() into get_mem/obj_cgroup_from_current() reduces the
number of call sites and allows further code simplifications.

Link: http://lkml.kernel.org/r/20200827225843.1270629-1-guro@fb.com
Link: http://lkml.kernel.org/r/20200827225843.1270629-2-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |   13 ++++++++-----
 mm/percpu.c     |    3 +--
 mm/slab.h       |    3 ---
 3 files changed, 9 insertions(+), 10 deletions(-)

--- a/mm/memcontrol.c~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/memcontrol.c
@@ -1066,6 +1066,9 @@ EXPORT_SYMBOL(get_mem_cgroup_from_page);
  */
 static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
 {
+	if (memcg_kmem_bypass())
+		return NULL;
+
 	if (unlikely(current->active_memcg)) {
 		struct mem_cgroup *memcg;
 
@@ -2933,6 +2936,9 @@ __always_inline struct obj_cgroup *get_o
 	struct obj_cgroup *objcg = NULL;
 	struct mem_cgroup *memcg;
 
+	if (memcg_kmem_bypass())
+		return NULL;
+
 	if (unlikely(!current->mm && !current->active_memcg))
 		return NULL;
 
@@ -3059,19 +3065,16 @@ int __memcg_kmem_charge_page(struct page
 	struct mem_cgroup *memcg;
 	int ret = 0;
 
-	if (memcg_kmem_bypass())
-		return 0;
-
 	memcg = get_mem_cgroup_from_current();
-	if (!mem_cgroup_is_root(memcg)) {
+	if (memcg && !mem_cgroup_is_root(memcg)) {
 		ret = __memcg_kmem_charge(memcg, gfp, 1 << order);
 		if (!ret) {
 			page->mem_cgroup = memcg;
 			__SetPageKmemcg(page);
 			return 0;
 		}
+		css_put(&memcg->css);
 	}
-	css_put(&memcg->css);
 	return ret;
 }
 
--- a/mm/percpu.c~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/percpu.c
@@ -1584,8 +1584,7 @@ static enum pcpu_chunk_type pcpu_memcg_p
 {
 	struct obj_cgroup *objcg;
 
-	if (!memcg_kmem_enabled() || !(gfp & __GFP_ACCOUNT) ||
-	    memcg_kmem_bypass())
+	if (!memcg_kmem_enabled() || !(gfp & __GFP_ACCOUNT))
 		return PCPU_CHUNK_ROOT;
 
 	objcg = get_obj_cgroup_from_current();
--- a/mm/slab.h~mm-kmem-move-memcg_kmem_bypass-calls-to-get_mem-obj_cgroup_from_current
+++ a/mm/slab.h
@@ -280,9 +280,6 @@ static inline struct obj_cgroup *memcg_s
 {
 	struct obj_cgroup *objcg;
 
-	if (memcg_kmem_bypass())
-		return NULL;
-
 	objcg = get_obj_cgroup_from_current();
 	if (!objcg)
 		return NULL;
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 04/40] mm: kmem: remove redundant checks from get_obj_cgroup_from_current()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (2 preceding siblings ...)
  2020-10-17 23:13 ` [patch 03/40] mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current() Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 05/40] mm: kmem: prepare remote memcg charging infra for interrupt contexts Andrew Morton
                   ` (35 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, guro, hannes, linux-mm, mhocko, mm-commits, shakeelb, torvalds

From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: remove redundant checks from get_obj_cgroup_from_current()

There are checks for current->mm and current->active_memcg in
get_obj_cgroup_from_current(), but these checks are redundant:
memcg_kmem_bypass() called just above performs same checks.

Link: http://lkml.kernel.org/r/20200827225843.1270629-3-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memcontrol.c |    3 ---
 1 file changed, 3 deletions(-)

--- a/mm/memcontrol.c~mm-kmem-remove-redundant-checks-from-get_obj_cgroup_from_current
+++ a/mm/memcontrol.c
@@ -2939,9 +2939,6 @@ __always_inline struct obj_cgroup *get_o
 	if (memcg_kmem_bypass())
 		return NULL;
 
-	if (unlikely(!current->mm && !current->active_memcg))
-		return NULL;
-
 	rcu_read_lock();
 	if (unlikely(current->active_memcg))
 		memcg = rcu_dereference(current->active_memcg);
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 05/40] mm: kmem: prepare remote memcg charging infra for interrupt contexts
  2020-10-17 23:13 incoming Andrew Morton
                   ` (3 preceding siblings ...)
  2020-10-17 23:13 ` [patch 04/40] mm: kmem: remove redundant checks from get_obj_cgroup_from_current() Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 06/40] mm: kmem: enable kernel memcg accounting from " Andrew Morton
                   ` (34 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, guro, hannes, linux-mm, mhocko, mm-commits, shakeelb, torvalds

From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: prepare remote memcg charging infra for interrupt contexts

Remote memcg charging API uses current->active_memcg to store the
currently active memory cgroup, which overwrites the memory cgroup of the
current process.  It works well for normal contexts, but doesn't work for
interrupt contexts: indeed, if an interrupt occurs during the execution of
a section with an active memcg set, all allocations inside the interrupt
will be charged to the active memcg set (given that we'll enable
accounting for allocations from an interrupt context).  But because the
interrupt might have no relation to the active memcg set outside, it's
obviously wrong from the accounting prospective.

To resolve this problem, let's add a global percpu int_active_memcg
variable, which will be used to store an active memory cgroup which will
be used from interrupt contexts.  set_active_memcg() will transparently
use current->active_memcg or int_active_memcg depending on the context.

To make the read part simple and transparent for the caller, let's
introduce two new functions:
  - struct mem_cgroup *active_memcg(void),
  - struct mem_cgroup *get_active_memcg(void).

They are returning the active memcg if it's set, hiding all implementation
details: where to get it depending on the current context.

Link: http://lkml.kernel.org/r/20200827225843.1270629-4-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/sched/mm.h |   13 ++++++++--
 mm/memcontrol.c          |   48 ++++++++++++++++++++++++++-----------
 2 files changed, 45 insertions(+), 16 deletions(-)

--- a/include/linux/sched/mm.h~mm-kmem-prepare-remote-memcg-charging-infra-for-interrupt-contexts
+++ a/include/linux/sched/mm.h
@@ -279,6 +279,7 @@ static inline void memalloc_nocma_restor
 #endif
 
 #ifdef CONFIG_MEMCG
+DECLARE_PER_CPU(struct mem_cgroup *, int_active_memcg);
 /**
  * set_active_memcg - Starts the remote memcg charging scope.
  * @memcg: memcg to charge.
@@ -293,8 +294,16 @@ static inline void memalloc_nocma_restor
 static inline struct mem_cgroup *
 set_active_memcg(struct mem_cgroup *memcg)
 {
-	struct mem_cgroup *old = current->active_memcg;
-	current->active_memcg = memcg;
+	struct mem_cgroup *old;
+
+	if (in_interrupt()) {
+		old = this_cpu_read(int_active_memcg);
+		this_cpu_write(int_active_memcg, memcg);
+	} else {
+		old = current->active_memcg;
+		current->active_memcg = memcg;
+	}
+
 	return old;
 }
 #else
--- a/mm/memcontrol.c~mm-kmem-prepare-remote-memcg-charging-infra-for-interrupt-contexts
+++ a/mm/memcontrol.c
@@ -73,6 +73,9 @@ EXPORT_SYMBOL(memory_cgrp_subsys);
 
 struct mem_cgroup *root_mem_cgroup __read_mostly;
 
+/* Active memory cgroup to use from an interrupt context */
+DEFINE_PER_CPU(struct mem_cgroup *, int_active_memcg);
+
 /* Socket memory accounting disabled? */
 static bool cgroup_memory_nosocket;
 
@@ -1061,26 +1064,43 @@ struct mem_cgroup *get_mem_cgroup_from_p
 }
 EXPORT_SYMBOL(get_mem_cgroup_from_page);
 
-/**
- * If current->active_memcg is non-NULL, do not fallback to current->mm->memcg.
- */
-static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
+static __always_inline struct mem_cgroup *active_memcg(void)
 {
-	if (memcg_kmem_bypass())
-		return NULL;
+	if (in_interrupt())
+		return this_cpu_read(int_active_memcg);
+	else
+		return current->active_memcg;
+}
 
-	if (unlikely(current->active_memcg)) {
-		struct mem_cgroup *memcg;
+static __always_inline struct mem_cgroup *get_active_memcg(void)
+{
+	struct mem_cgroup *memcg;
 
-		rcu_read_lock();
+	rcu_read_lock();
+	memcg = active_memcg();
+	if (memcg) {
 		/* current->active_memcg must hold a ref. */
-		if (WARN_ON_ONCE(!css_tryget(&current->active_memcg->css)))
+		if (WARN_ON_ONCE(!css_tryget(&memcg->css)))
 			memcg = root_mem_cgroup;
 		else
 			memcg = current->active_memcg;
-		rcu_read_unlock();
-		return memcg;
 	}
+	rcu_read_unlock();
+
+	return memcg;
+}
+
+/**
+ * If active memcg is set, do not fallback to current->mm->memcg.
+ */
+static __always_inline struct mem_cgroup *get_mem_cgroup_from_current(void)
+{
+	if (memcg_kmem_bypass())
+		return NULL;
+
+	if (unlikely(active_memcg()))
+		return get_active_memcg();
+
 	return get_mem_cgroup_from_mm(current->mm);
 }
 
@@ -2940,8 +2960,8 @@ __always_inline struct obj_cgroup *get_o
 		return NULL;
 
 	rcu_read_lock();
-	if (unlikely(current->active_memcg))
-		memcg = rcu_dereference(current->active_memcg);
+	if (unlikely(active_memcg()))
+		memcg = active_memcg();
 	else
 		memcg = mem_cgroup_from_task(current);
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 06/40] mm: kmem: enable kernel memcg accounting from interrupt contexts
  2020-10-17 23:13 incoming Andrew Morton
                   ` (4 preceding siblings ...)
  2020-10-17 23:13 ` [patch 05/40] mm: kmem: prepare remote memcg charging infra for interrupt contexts Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:13 ` [patch 07/40] mm/memory-failure: remove a wrapper for alloc_migration_target() Andrew Morton
                   ` (33 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, guro, hannes, linux-mm, mhocko, mm-commits, shakeelb, torvalds

From: Roman Gushchin <guro@fb.com>
Subject: mm: kmem: enable kernel memcg accounting from interrupt contexts

If a memcg to charge can be determined (using remote charging API), there
are no reasons to exclude allocations made from an interrupt context from
the accounting.

Such allocations will pass even if the resulting memcg size will exceed
the hard limit, but it will affect the application of the memory pressure
and an inability to put the workload under the limit will eventually
trigger the OOM.

To use active_memcg() helper, memcg_kmem_bypass() is moved back to
memcontrol.c.

Link: http://lkml.kernel.org/r/20200827225843.1270629-5-guro@fb.com
Signed-off-by: Roman Gushchin <guro@fb.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/memcontrol.h |   12 ------------
 mm/memcontrol.c            |   13 +++++++++++++
 2 files changed, 13 insertions(+), 12 deletions(-)

--- a/include/linux/memcontrol.h~mm-kmem-enable-kernel-memcg-accounting-from-interrupt-contexts
+++ a/include/linux/memcontrol.h
@@ -1531,18 +1531,6 @@ static inline bool memcg_kmem_enabled(vo
 	return static_branch_likely(&memcg_kmem_enabled_key);
 }
 
-static inline bool memcg_kmem_bypass(void)
-{
-	if (in_interrupt())
-		return true;
-
-	/* Allow remote memcg charging in kthread contexts. */
-	if ((!current->mm || (current->flags & PF_KTHREAD)) &&
-	     !current->active_memcg)
-		return true;
-	return false;
-}
-
 static inline int memcg_kmem_charge_page(struct page *page, gfp_t gfp,
 					 int order)
 {
--- a/mm/memcontrol.c~mm-kmem-enable-kernel-memcg-accounting-from-interrupt-contexts
+++ a/mm/memcontrol.c
@@ -1090,6 +1090,19 @@ static __always_inline struct mem_cgroup
 	return memcg;
 }
 
+static __always_inline bool memcg_kmem_bypass(void)
+{
+	/* Allow remote memcg charging from any context. */
+	if (unlikely(active_memcg()))
+		return false;
+
+	/* Memcg to charge can't be determined. */
+	if (in_interrupt() || !current->mm || (current->flags & PF_KTHREAD))
+		return true;
+
+	return false;
+}
+
 /**
  * If active memcg is set, do not fallback to current->mm->memcg.
  */
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 07/40] mm/memory-failure: remove a wrapper for alloc_migration_target()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (5 preceding siblings ...)
  2020-10-17 23:13 ` [patch 06/40] mm: kmem: enable kernel memcg accounting from " Andrew Morton
@ 2020-10-17 23:13 ` Andrew Morton
  2020-10-17 23:14 ` [patch 08/40] mm/memory_hotplug: " Andrew Morton
                   ` (32 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:13 UTC (permalink / raw)
  To: akpm, guro, hch, iamjoonsoo.kim, linux-mm, mhocko, mike.kravetz,
	mm-commits, n-horiguchi, torvalds, vbabka

From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: mm/memory-failure: remove a wrapper for alloc_migration_target()

There is a well-defined standard migration target callback.  Use it
directly.

Link: http://lkml.kernel.org/r/1594622517-20681-9-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory-failure.c |   18 ++++++------------
 1 file changed, 6 insertions(+), 12 deletions(-)

--- a/mm/memory-failure.c~mm-memory-failure-remove-a-wrapper-for-alloc_migration_target
+++ a/mm/memory-failure.c
@@ -1673,16 +1673,6 @@ int unpoison_memory(unsigned long pfn)
 }
 EXPORT_SYMBOL(unpoison_memory);
 
-static struct page *new_page(struct page *p, unsigned long private)
-{
-	struct migration_target_control mtc = {
-		.nid = page_to_nid(p),
-		.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
-	};
-
-	return alloc_migration_target(p, (unsigned long)&mtc);
-}
-
 /*
  * Safely get reference count of an arbitrary page.
  * Returns 0 for a free page, -EIO for a zero refcount page
@@ -1797,6 +1787,10 @@ static int __soft_offline_page(struct pa
 	char const *msg_page[] = {"page", "hugepage"};
 	bool huge = PageHuge(page);
 	LIST_HEAD(pagelist);
+	struct migration_target_control mtc = {
+		.nid = NUMA_NO_NODE,
+		.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
+	};
 
 	/*
 	 * Check PageHWPoison again inside page lock because PageHWPoison
@@ -1833,8 +1827,8 @@ static int __soft_offline_page(struct pa
 	}
 
 	if (isolate_page(hpage, &pagelist)) {
-		ret = migrate_pages(&pagelist, new_page, NULL, MPOL_MF_MOVE_ALL,
-					MIGRATE_SYNC, MR_MEMORY_FAILURE);
+		ret = migrate_pages(&pagelist, alloc_migration_target, NULL,
+			(unsigned long)&mtc, MIGRATE_SYNC, MR_MEMORY_FAILURE);
 		if (!ret) {
 			bool release = !huge;
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 08/40] mm/memory_hotplug: remove a wrapper for alloc_migration_target()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (6 preceding siblings ...)
  2020-10-17 23:13 ` [patch 07/40] mm/memory-failure: remove a wrapper for alloc_migration_target() Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 09/40] mm/migrate: avoid possible unnecessary process right check in kernel_move_pages() Andrew Morton
                   ` (31 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, guro, hch, iamjoonsoo.kim, linux-mm, mhocko, mike.kravetz,
	mm-commits, n-horiguchi, torvalds, vbabka

From: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Subject: mm/memory_hotplug: remove a wrapper for alloc_migration_target()

To calculate the correct node to migrate the page for hotplug, we need to
check node id of the page.  Wrapper for alloc_migration_target() exists
for this purpose.

However, Vlastimil informs that all migration source pages come from a
single node.  In this case, we don't need to check the node id for each
page and we don't need to re-set the target nodemask for each page by
using the wrapper.  Set up the migration_target_control once and use it
for all pages.

Link: http://lkml.kernel.org/r/1594622517-20681-10-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory_hotplug.c |   46 ++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 24 deletions(-)

--- a/mm/memory_hotplug.c~mm-memory_hotplug-remove-a-wrapper-for-alloc_migration_target
+++ a/mm/memory_hotplug.c
@@ -1290,27 +1290,6 @@ found:
 	return 0;
 }
 
-static struct page *new_node_page(struct page *page, unsigned long private)
-{
-	nodemask_t nmask = node_states[N_MEMORY];
-	struct migration_target_control mtc = {
-		.nid = page_to_nid(page),
-		.nmask = &nmask,
-		.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
-	};
-
-	/*
-	 * try to allocate from a different node but reuse this node if there
-	 * are no other online nodes to be used (e.g. we are offlining a part
-	 * of the only existing node)
-	 */
-	node_clear(mtc.nid, nmask);
-	if (nodes_empty(nmask))
-		node_set(mtc.nid, nmask);
-
-	return alloc_migration_target(page, (unsigned long)&mtc);
-}
-
 static int
 do_migrate_range(unsigned long start_pfn, unsigned long end_pfn)
 {
@@ -1370,9 +1349,28 @@ do_migrate_range(unsigned long start_pfn
 		put_page(page);
 	}
 	if (!list_empty(&source)) {
-		/* Allocate a new page from the nearest neighbor node */
-		ret = migrate_pages(&source, new_node_page, NULL, 0,
-					MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
+		nodemask_t nmask = node_states[N_MEMORY];
+		struct migration_target_control mtc = {
+			.nmask = &nmask,
+			.gfp_mask = GFP_USER | __GFP_MOVABLE | __GFP_RETRY_MAYFAIL,
+		};
+
+		/*
+		 * We have checked that migration range is on a single zone so
+		 * we can use the nid of the first page to all the others.
+		 */
+		mtc.nid = page_to_nid(list_first_entry(&source, struct page, lru));
+
+		/*
+		 * try to allocate from a different node but reuse this node
+		 * if there are no other online nodes to be used (e.g. we are
+		 * offlining a part of the only existing node)
+		 */
+		node_clear(mtc.nid, nmask);
+		if (nodes_empty(nmask))
+			node_set(mtc.nid, nmask);
+		ret = migrate_pages(&source, alloc_migration_target, NULL,
+			(unsigned long)&mtc, MIGRATE_SYNC, MR_MEMORY_HOTPLUG);
 		if (ret) {
 			list_for_each_entry(page, &source, lru) {
 				pr_warn("migrating pfn %lx failed ret:%d ",
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 09/40] mm/migrate: avoid possible unnecessary process right check in kernel_move_pages()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (7 preceding siblings ...)
  2020-10-17 23:14 ` [patch 08/40] mm/memory_hotplug: " Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code Andrew Morton
                   ` (30 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, cl, linmiaohe, linux-mm, louhongxiang, mm-commits, torvalds, willy

From: Miaohe Lin <linmiaohe@huawei.com>
Subject: mm/migrate: avoid possible unnecessary process right check in kernel_move_pages()

There is no need to check if this process has the right to modify the
specified process when they are same.  And we could also skip the security
hook call if a process is modifying its own pages.  Add helper function to
handle these.

Link: https://lkml.kernel.org/r/20200819083331.19012-1-linmiaohe@huawei.com
Signed-off-by: Hongxiang Lou <louhongxiang@huawei.com>
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Suggested-by: Matthew Wilcox <willy@infradead.org>
Cc: Christopher Lameter <cl@linux.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/migrate.c |   71 +++++++++++++++++++++++++++++--------------------
 1 file changed, 43 insertions(+), 28 deletions(-)

--- a/mm/migrate.c~mm-migrate-avoid-possible-unnecessary-process-right-check-in-kernel_move_pages
+++ a/mm/migrate.c
@@ -1864,33 +1864,27 @@ static int do_pages_stat(struct mm_struc
 	return nr_pages ? -EFAULT : 0;
 }
 
-/*
- * Move a list of pages in the address space of the currently executing
- * process.
- */
-static int kernel_move_pages(pid_t pid, unsigned long nr_pages,
-			     const void __user * __user *pages,
-			     const int __user *nodes,
-			     int __user *status, int flags)
+static struct mm_struct *find_mm_struct(pid_t pid, nodemask_t *mem_nodes)
 {
 	struct task_struct *task;
 	struct mm_struct *mm;
-	int err;
-	nodemask_t task_nodes;
-
-	/* Check flags */
-	if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL))
-		return -EINVAL;
 
-	if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
-		return -EPERM;
+	/*
+	 * There is no need to check if current process has the right to modify
+	 * the specified process when they are same.
+	 */
+	if (!pid) {
+		mmget(current->mm);
+		*mem_nodes = cpuset_mems_allowed(current);
+		return current->mm;
+	}
 
 	/* Find the mm_struct */
 	rcu_read_lock();
-	task = pid ? find_task_by_vpid(pid) : current;
+	task = find_task_by_vpid(pid);
 	if (!task) {
 		rcu_read_unlock();
-		return -ESRCH;
+		return ERR_PTR(-ESRCH);
 	}
 	get_task_struct(task);
 
@@ -1900,22 +1894,47 @@ static int kernel_move_pages(pid_t pid,
 	 */
 	if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) {
 		rcu_read_unlock();
-		err = -EPERM;
+		mm = ERR_PTR(-EPERM);
 		goto out;
 	}
 	rcu_read_unlock();
 
- 	err = security_task_movememory(task);
- 	if (err)
+	mm = ERR_PTR(security_task_movememory(task));
+	if (IS_ERR(mm))
 		goto out;
-
-	task_nodes = cpuset_mems_allowed(task);
+	*mem_nodes = cpuset_mems_allowed(task);
 	mm = get_task_mm(task);
+out:
 	put_task_struct(task);
-
 	if (!mm)
+		mm = ERR_PTR(-EINVAL);
+	return mm;
+}
+
+/*
+ * Move a list of pages in the address space of the currently executing
+ * process.
+ */
+static int kernel_move_pages(pid_t pid, unsigned long nr_pages,
+			     const void __user * __user *pages,
+			     const int __user *nodes,
+			     int __user *status, int flags)
+{
+	struct mm_struct *mm;
+	int err;
+	nodemask_t task_nodes;
+
+	/* Check flags */
+	if (flags & ~(MPOL_MF_MOVE|MPOL_MF_MOVE_ALL))
 		return -EINVAL;
 
+	if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE))
+		return -EPERM;
+
+	mm = find_mm_struct(pid, &task_nodes);
+	if (IS_ERR(mm))
+		return PTR_ERR(mm);
+
 	if (nodes)
 		err = do_pages_move(mm, task_nodes, nr_pages, pages,
 				    nodes, status, flags);
@@ -1924,10 +1943,6 @@ static int kernel_move_pages(pid_t pid,
 
 	mmput(mm);
 	return err;
-
-out:
-	put_task_struct(task);
-	return err;
 }
 
 SYSCALL_DEFINE6(move_pages, pid_t, pid, unsigned long, nr_pages,
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code
  2020-10-17 23:13 incoming Andrew Morton
                   ` (8 preceding siblings ...)
  2020-10-17 23:14 ` [patch 09/40] mm/migrate: avoid possible unnecessary process right check in kernel_move_pages() Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 11/40] mm/mmap: add inline munmap_vma_range() for code readability Andrew Morton
                   ` (29 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, Liam.Howlett, linux-mm, mm-commits, torvalds

From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
Subject: mm/mmap: add inline vma_next() for readability of mmap code

There are three places that the next vma is required which uses the same
block of code.  Replace the block with a function and add comments on what
happens in the case where NULL is encountered.

Link: http://lkml.kernel.org/r/20200818154707.2515169-1-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |   26 ++++++++++++++++++++------
 1 file changed, 20 insertions(+), 6 deletions(-)

--- a/mm/mmap.c~mm-mmap-add-inline-vma_next-for-readability-of-mmap-code
+++ a/mm/mmap.c
@@ -558,6 +558,23 @@ static int find_vma_links(struct mm_stru
 	return 0;
 }
 
+/*
+ * vma_next() - Get the next VMA.
+ * @mm: The mm_struct.
+ * @vma: The current vma.
+ *
+ * If @vma is NULL, return the first vma in the mm.
+ *
+ * Returns: The next VMA after @vma.
+ */
+static inline struct vm_area_struct *vma_next(struct mm_struct *mm,
+					 struct vm_area_struct *vma)
+{
+	if (!vma)
+		return mm->mmap;
+
+	return vma->vm_next;
+}
 static unsigned long count_vma_pages_range(struct mm_struct *mm,
 		unsigned long addr, unsigned long end)
 {
@@ -1128,10 +1145,7 @@ struct vm_area_struct *vma_merge(struct
 	if (vm_flags & VM_SPECIAL)
 		return NULL;
 
-	if (prev)
-		next = prev->vm_next;
-	else
-		next = mm->mmap;
+	next = vma_next(mm, prev);
 	area = next;
 	if (area && area->vm_end == end)		/* cases 6, 7, 8 */
 		next = next->vm_next;
@@ -2632,7 +2646,7 @@ static void unmap_region(struct mm_struc
 		struct vm_area_struct *vma, struct vm_area_struct *prev,
 		unsigned long start, unsigned long end)
 {
-	struct vm_area_struct *next = prev ? prev->vm_next : mm->mmap;
+	struct vm_area_struct *next = vma_next(mm, prev);
 	struct mmu_gather tlb;
 
 	lru_add_drain();
@@ -2831,7 +2845,7 @@ int __do_munmap(struct mm_struct *mm, un
 		if (error)
 			return error;
 	}
-	vma = prev ? prev->vm_next : mm->mmap;
+	vma = vma_next(mm, prev);
 
 	if (unlikely(uf)) {
 		/*
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 11/40] mm/mmap: add inline munmap_vma_range() for code readability
  2020-10-17 23:13 incoming Andrew Morton
                   ` (9 preceding siblings ...)
  2020-10-17 23:14 ` [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 12/40] mm/gup_benchmark: take the mmap lock around GUP Andrew Morton
                   ` (28 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, Liam.Howlett, linux-mm, mm-commits, torvalds

From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
Subject: mm/mmap: add inline munmap_vma_range() for code readability

There are two locations that have a block of code for munmapping a vma
range.  Change those two locations to use a function and add meaningful
comments about what happens to the arguments, which was unclear in the
previous code.

Link: http://lkml.kernel.org/r/20200818154707.2515169-2-Liam.Howlett@Oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/mmap.c |   48 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 33 insertions(+), 15 deletions(-)

--- a/mm/mmap.c~mm-mmap-add-inline-munmap_vma_range-for-code-readability
+++ a/mm/mmap.c
@@ -575,6 +575,33 @@ static inline struct vm_area_struct *vma
 
 	return vma->vm_next;
 }
+
+/*
+ * munmap_vma_range() - munmap VMAs that overlap a range.
+ * @mm: The mm struct
+ * @start: The start of the range.
+ * @len: The length of the range.
+ * @pprev: pointer to the pointer that will be set to previous vm_area_struct
+ * @rb_link: the rb_node
+ * @rb_parent: the parent rb_node
+ *
+ * Find all the vm_area_struct that overlap from @start to
+ * @end and munmap them.  Set @pprev to the previous vm_area_struct.
+ *
+ * Returns: -ENOMEM on munmap failure or 0 on success.
+ */
+static inline int
+munmap_vma_range(struct mm_struct *mm, unsigned long start, unsigned long len,
+		 struct vm_area_struct **pprev, struct rb_node ***link,
+		 struct rb_node **parent, struct list_head *uf)
+{
+
+	while (find_vma_links(mm, start, start + len, pprev, link, parent))
+		if (do_munmap(mm, start, len, uf))
+			return -ENOMEM;
+
+	return 0;
+}
 static unsigned long count_vma_pages_range(struct mm_struct *mm,
 		unsigned long addr, unsigned long end)
 {
@@ -1721,13 +1748,9 @@ unsigned long mmap_region(struct file *f
 			return -ENOMEM;
 	}
 
-	/* Clear old maps */
-	while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
-			      &rb_parent)) {
-		if (do_munmap(mm, addr, len, uf))
-			return -ENOMEM;
-	}
-
+	/* Clear old maps, set up prev, rb_link, rb_parent, and uf */
+	if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf))
+		return -ENOMEM;
 	/*
 	 * Private writable mapping: check memory availability
 	 */
@@ -3063,14 +3086,9 @@ static int do_brk_flags(unsigned long ad
 	if (error)
 		return error;
 
-	/*
-	 * Clear old maps.  this also does some error checking for us
-	 */
-	while (find_vma_links(mm, addr, addr + len, &prev, &rb_link,
-			      &rb_parent)) {
-		if (do_munmap(mm, addr, len, uf))
-			return -ENOMEM;
-	}
+	/* Clear old maps, set up prev, rb_link, rb_parent, and uf */
+	if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf))
+		return -ENOMEM;
 
 	/* Check against address space limits *after* clearing old maps... */
 	if (!may_expand_vm(mm, flags, len >> PAGE_SHIFT))
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 12/40] mm/gup_benchmark: take the mmap lock around GUP
  2020-10-17 23:13 incoming Andrew Morton
                   ` (10 preceding siblings ...)
  2020-10-17 23:14 ` [patch 11/40] mm/mmap: add inline munmap_vma_range() for code readability Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 13/40] binfmt_elf: take the mmap lock around find_extend_vma() Andrew Morton
                   ` (27 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, ebiederm, jannh, jgg, jhubbard, linux-mm, mchehab,
	mm-commits, sakari.ailus, torvalds, walken

From: Jann Horn <jannh@google.com>
Subject: mm/gup_benchmark: take the mmap lock around GUP

To be safe against concurrent changes to the VMA tree, we must take the
mmap lock around GUP operations (excluding the GUP-fast family of
operations, which will take the mmap lock by themselves if necessary).

This code is only for testing, and it's only reachable by root through
debugfs, so this doesn't really have any impact; however, if we want to
add lockdep asserts into the GUP path, we need to have clean locking here.

Link: https://lkml.kernel.org/r/CAG48ez3SG6ngZLtasxJ6LABpOnqCz5-QHqb0B4k44TQ8F9n6+w@mail.gmail.com
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: Michel Lespinasse <walken@google.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/gup_benchmark.c |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

--- a/mm/gup_benchmark.c~mm-gup_benchmark-take-the-mmap-lock-around-gup
+++ a/mm/gup_benchmark.c
@@ -72,6 +72,8 @@ static int __gup_benchmark_ioctl(unsigne
 	int nr;
 	struct page **pages;
 	int ret = 0;
+	bool needs_mmap_lock =
+		cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK;
 
 	if (gup->size > ULONG_MAX)
 		return -EINVAL;
@@ -81,6 +83,11 @@ static int __gup_benchmark_ioctl(unsigne
 	if (!pages)
 		return -ENOMEM;
 
+	if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) {
+		ret = -EINTR;
+		goto free_pages;
+	}
+
 	i = 0;
 	nr = gup->nr_pages_per_call;
 	start_time = ktime_get();
@@ -120,9 +127,8 @@ static int __gup_benchmark_ioctl(unsigne
 					    pages + i, NULL);
 			break;
 		default:
-			kvfree(pages);
 			ret = -EINVAL;
-			goto out;
+			goto unlock;
 		}
 
 		if (nr <= 0)
@@ -150,8 +156,11 @@ static int __gup_benchmark_ioctl(unsigne
 	end_time = ktime_get();
 	gup->put_delta_usec = ktime_us_delta(end_time, start_time);
 
+unlock:
+	if (needs_mmap_lock)
+		mmap_read_unlock(current->mm);
+free_pages:
 	kvfree(pages);
-out:
 	return ret;
 }
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 13/40] binfmt_elf: take the mmap lock around find_extend_vma()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (11 preceding siblings ...)
  2020-10-17 23:14 ` [patch 12/40] mm/gup_benchmark: take the mmap lock around GUP Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages() Andrew Morton
                   ` (26 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, ebiederm, jannh, jgg, jhubbard, linux-mm, mchehab,
	mm-commits, sakari.ailus, torvalds, walken

From: Jann Horn <jannh@google.com>
Subject: binfmt_elf: take the mmap lock around find_extend_vma()

create_elf_tables() runs after setup_new_exec(), so other tasks can
already access our new mm and do things like process_madvise() on it.  (At
the time I'm writing this commit, process_madvise() is not in mainline
yet, but has been in akpm's tree for some time.)

While I believe that there are currently no APIs that would actually allow
another process to mess up our VMA tree (process_madvise() is limited to
MADV_COLD and MADV_PAGEOUT, and uring and userfaultfd cannot reach an mm
under which no syscalls have been executed yet), this seems like an
accident waiting to happen.

Let's make sure that we always take the mmap lock around GUP paths as long
as another process might be able to see the mm.

(Yes, this diff looks suspicious because we drop the lock before doing
anything with `vma`, but that's because we actually don't do anything with
it apart from the NULL check.)

Link: https://lkml.kernel.org/r/CAG48ez1-PBCdv3y8pn-Ty-b+FmBSLwDuVKFSt8h7wARLy0dF-Q@mail.gmail.com
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Michel Lespinasse <walken@google.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/binfmt_elf.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/fs/binfmt_elf.c~binfmt_elf-take-the-mmap-lock-around-find_extend_vma
+++ a/fs/binfmt_elf.c
@@ -310,7 +310,10 @@ create_elf_tables(struct linux_binprm *b
 	 * Grow the stack manually; some architectures have a limit on how
 	 * far ahead a user-space access may be in order to grow the stack.
 	 */
+	if (mmap_read_lock_killable(mm))
+		return -EINTR;
 	vma = find_extend_vma(mm, bprm->p);
+	mmap_read_unlock(mm);
 	if (!vma)
 		return -EFAULT;
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages()
  2020-10-17 23:13 incoming Andrew Morton
                   ` (12 preceding siblings ...)
  2020-10-17 23:14 ` [patch 13/40] binfmt_elf: take the mmap lock around find_extend_vma() Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-18  1:28   ` Jann Horn
  2020-10-17 23:14 ` [patch 15/40] mm/gup_benchmark: rename to mm/gup_test Andrew Morton
                   ` (25 subsequent siblings)
  39 siblings, 1 reply; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, ebiederm, jannh, jgg, jhubbard, linux-mm, mchehab,
	mm-commits, sakari.ailus, torvalds, walken

From: Jann Horn <jannh@google.com>
Subject: mm/gup: assert that the mmap lock is held in __get_user_pages()

After having cleaned up all GUP callers (except for the atomisp staging
driver, which currently gets mmap locking completely wrong [1]) to always
ensure that they hold the mmap lock when calling into GUP (unless the mm
is not yet globally visible), add an assertion to make sure it stays that
way going forward.

[1] https://lore.kernel.org/lkml/CAG48ez3tZAb9JVhw4T5e-i=h2_DUZxfNRTDsagSRCVazNXx5qA@mail.gmail.com/

Link: https://lkml.kernel.org/r/CAG48ez1GM==OnHpS=ghqZNJPn02FCDUEHc7GQmGRMXUD_aKudg@mail.gmail.com
Signed-off-by: Jann Horn <jannh@google.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Acked-by: Michel Lespinasse <walken@google.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/gup.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/mm/gup.c~mm-gup-assert-that-the-mmap-lock-is-held-in-__get_user_pages
+++ a/mm/gup.c
@@ -1027,6 +1027,8 @@ static long __get_user_pages(struct mm_s
 	struct vm_area_struct *vma = NULL;
 	struct follow_page_context ctx = { NULL };
 
+	mmap_assert_locked(mm);
+
 	if (!nr_pages)
 		return 0;
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 15/40] mm/gup_benchmark: rename to mm/gup_test
  2020-10-17 23:13 incoming Andrew Morton
                   ` (13 preceding siblings ...)
  2020-10-17 23:14 ` [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages() Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 16/40] selftests/vm: use a common gup_test.h Andrew Morton
                   ` (24 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: mm/gup_benchmark: rename to mm/gup_test

Patch series "selftests/vm: gup_test, hmm-tests, assorted improvements", v2.

This series provides two main things, and a number of smaller supporting
goodies.  The two main points are:

1) Add a new sub-test to gup_test, which in turn is a renamed version
   of gup_benchmark.  This sub-test allows nicer testing of dump_pages(),
   at least on user-space pages.

   For quite a while, I was doing a quick hack to gup_test.c whenever I
   wanted to try out changes to dump_page().  Then Matthew Wilcox asked me
   what I meant when I said "I used my dump_page() unit test", and I
   realized that it might be nice to check in a polished up version of
   that.

   Details about how it works and how to use it are in the commit
   description for patch #6.

2) Fixes a limitation of hmm-tests: these tests are incredibly useful,
   but only if people actually build and run them.  And it turns out that
   libhugetlbfs is a little too effective at throwing a wrench in the
   works, there.  So I've added a little configuration check that removes
   just two of the 21 hmm-tests, if libhugetlbfs is not available.

   Further details in the commit description of patch #8.

Other smaller things that this series does:

a) Remove code duplication by creating gup_test.h.

b) Clear up the sub-test organization, and their invocation within
   run_vmtests.sh.

c) Other minor assorted improvements.


This patch (of 8):

Rename nearly every "gup_benchmark" reference and file name to "gup_test".
The one exception is for the actual gup benchmark test itself.

The current code already does a *little* bit more than benchmarking, and
definitely covers more than get_user_pages_fast().  More importantly,
however, subsequent patches are about to add some functionality that is
non-benchmark related.

Closely related changes:

* Kconfig: in addition to renaming the options from GUP_BENCHMARK to
  GUP_TEST, update the help text to reflect that it's no longer a
  benchmark-only test.

Link: https://lkml.kernel.org/r/20200929212747.251804-1-jhubbard@nvidia.com
Link: https://lkml.kernel.org/r/20200929212747.251804-2-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
CC: Jonathan Corbet <corbet@lwn.net>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 Documentation/core-api/pin_user_pages.rst  |    6 
 arch/s390/configs/debug_defconfig          |    2 
 arch/s390/configs/defconfig                |    2 
 mm/Kconfig                                 |   15 -
 mm/Makefile                                |    2 
 mm/gup_benchmark.c                         |  210 -------------------
 mm/gup_test.c                              |  210 +++++++++++++++++++
 tools/testing/selftests/vm/.gitignore      |    2 
 tools/testing/selftests/vm/Makefile        |    2 
 tools/testing/selftests/vm/config          |    2 
 tools/testing/selftests/vm/gup_benchmark.c |  143 ------------
 tools/testing/selftests/vm/gup_test.c      |  143 ++++++++++++
 tools/testing/selftests/vm/run_vmtests     |    8 
 13 files changed, 376 insertions(+), 371 deletions(-)

--- a/arch/s390/configs/debug_defconfig~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/arch/s390/configs/debug_defconfig
@@ -100,7 +100,7 @@ CONFIG_ZSMALLOC_STAT=y
 CONFIG_DEFERRED_STRUCT_PAGE_INIT=y
 CONFIG_IDLE_PAGE_TRACKING=y
 CONFIG_PERCPU_STATS=y
-CONFIG_GUP_BENCHMARK=y
+CONFIG_GUP_TEST=y
 CONFIG_NET=y
 CONFIG_PACKET=y
 CONFIG_PACKET_DIAG=m
--- a/arch/s390/configs/defconfig~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/arch/s390/configs/defconfig
@@ -94,7 +94,7 @@ CONFIG_ZSMALLOC_STAT=y
 CONFIG_DEFERRED_STRUCT_PAGE_INIT=y
 CONFIG_IDLE_PAGE_TRACKING=y
 CONFIG_PERCPU_STATS=y
-CONFIG_GUP_BENCHMARK=y
+CONFIG_GUP_TEST=y
 CONFIG_NET=y
 CONFIG_PACKET=y
 CONFIG_PACKET_DIAG=m
--- a/Documentation/core-api/pin_user_pages.rst~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/Documentation/core-api/pin_user_pages.rst
@@ -221,12 +221,12 @@ Unit testing
 ============
 This file::
 
- tools/testing/selftests/vm/gup_benchmark.c
+ tools/testing/selftests/vm/gup_test.c
 
 has the following new calls to exercise the new pin*() wrapper functions:
 
-* PIN_FAST_BENCHMARK (./gup_benchmark -a)
-* PIN_BENCHMARK (./gup_benchmark -b)
+* PIN_FAST_BENCHMARK (./gup_test -a)
+* PIN_BENCHMARK (./gup_test -b)
 
 You can monitor how many total dma-pinned pages have been acquired and released
 since the system was booted, via two new /proc/vmstat entries: ::
--- a/mm/gup_benchmark.c
+++ /dev/null
@@ -1,210 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/uaccess.h>
-#include <linux/ktime.h>
-#include <linux/debugfs.h>
-
-#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_benchmark)
-#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_benchmark)
-#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_benchmark)
-#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_benchmark)
-#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_benchmark)
-
-struct gup_benchmark {
-	__u64 get_delta_usec;
-	__u64 put_delta_usec;
-	__u64 addr;
-	__u64 size;
-	__u32 nr_pages_per_call;
-	__u32 flags;
-	__u64 expansion[10];	/* For future use */
-};
-
-static void put_back_pages(unsigned int cmd, struct page **pages,
-			   unsigned long nr_pages)
-{
-	unsigned long i;
-
-	switch (cmd) {
-	case GUP_FAST_BENCHMARK:
-	case GUP_BENCHMARK:
-		for (i = 0; i < nr_pages; i++)
-			put_page(pages[i]);
-		break;
-
-	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
-	case PIN_LONGTERM_BENCHMARK:
-		unpin_user_pages(pages, nr_pages);
-		break;
-	}
-}
-
-static void verify_dma_pinned(unsigned int cmd, struct page **pages,
-			      unsigned long nr_pages)
-{
-	unsigned long i;
-	struct page *page;
-
-	switch (cmd) {
-	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
-	case PIN_LONGTERM_BENCHMARK:
-		for (i = 0; i < nr_pages; i++) {
-			page = pages[i];
-			if (WARN(!page_maybe_dma_pinned(page),
-				 "pages[%lu] is NOT dma-pinned\n", i)) {
-
-				dump_page(page, "gup_benchmark failure");
-				break;
-			}
-		}
-		break;
-	}
-}
-
-static int __gup_benchmark_ioctl(unsigned int cmd,
-		struct gup_benchmark *gup)
-{
-	ktime_t start_time, end_time;
-	unsigned long i, nr_pages, addr, next;
-	int nr;
-	struct page **pages;
-	int ret = 0;
-	bool needs_mmap_lock =
-		cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK;
-
-	if (gup->size > ULONG_MAX)
-		return -EINVAL;
-
-	nr_pages = gup->size / PAGE_SIZE;
-	pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL);
-	if (!pages)
-		return -ENOMEM;
-
-	if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) {
-		ret = -EINTR;
-		goto free_pages;
-	}
-
-	i = 0;
-	nr = gup->nr_pages_per_call;
-	start_time = ktime_get();
-	for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) {
-		if (nr != gup->nr_pages_per_call)
-			break;
-
-		next = addr + nr * PAGE_SIZE;
-		if (next > gup->addr + gup->size) {
-			next = gup->addr + gup->size;
-			nr = (next - addr) / PAGE_SIZE;
-		}
-
-		/* Filter out most gup flags: only allow a tiny subset here: */
-		gup->flags &= FOLL_WRITE;
-
-		switch (cmd) {
-		case GUP_FAST_BENCHMARK:
-			nr = get_user_pages_fast(addr, nr, gup->flags,
-						 pages + i);
-			break;
-		case GUP_BENCHMARK:
-			nr = get_user_pages(addr, nr, gup->flags, pages + i,
-					    NULL);
-			break;
-		case PIN_FAST_BENCHMARK:
-			nr = pin_user_pages_fast(addr, nr, gup->flags,
-						 pages + i);
-			break;
-		case PIN_BENCHMARK:
-			nr = pin_user_pages(addr, nr, gup->flags, pages + i,
-					    NULL);
-			break;
-		case PIN_LONGTERM_BENCHMARK:
-			nr = pin_user_pages(addr, nr,
-					    gup->flags | FOLL_LONGTERM,
-					    pages + i, NULL);
-			break;
-		default:
-			ret = -EINVAL;
-			goto unlock;
-		}
-
-		if (nr <= 0)
-			break;
-		i += nr;
-	}
-	end_time = ktime_get();
-
-	/* Shifting the meaning of nr_pages: now it is actual number pinned: */
-	nr_pages = i;
-
-	gup->get_delta_usec = ktime_us_delta(end_time, start_time);
-	gup->size = addr - gup->addr;
-
-	/*
-	 * Take an un-benchmark-timed moment to verify DMA pinned
-	 * state: print a warning if any non-dma-pinned pages are found:
-	 */
-	verify_dma_pinned(cmd, pages, nr_pages);
-
-	start_time = ktime_get();
-
-	put_back_pages(cmd, pages, nr_pages);
-
-	end_time = ktime_get();
-	gup->put_delta_usec = ktime_us_delta(end_time, start_time);
-
-unlock:
-	if (needs_mmap_lock)
-		mmap_read_unlock(current->mm);
-free_pages:
-	kvfree(pages);
-	return ret;
-}
-
-static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd,
-		unsigned long arg)
-{
-	struct gup_benchmark gup;
-	int ret;
-
-	switch (cmd) {
-	case GUP_FAST_BENCHMARK:
-	case GUP_BENCHMARK:
-	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
-	case PIN_LONGTERM_BENCHMARK:
-		break;
-	default:
-		return -EINVAL;
-	}
-
-	if (copy_from_user(&gup, (void __user *)arg, sizeof(gup)))
-		return -EFAULT;
-
-	ret = __gup_benchmark_ioctl(cmd, &gup);
-	if (ret)
-		return ret;
-
-	if (copy_to_user((void __user *)arg, &gup, sizeof(gup)))
-		return -EFAULT;
-
-	return 0;
-}
-
-static const struct file_operations gup_benchmark_fops = {
-	.open = nonseekable_open,
-	.unlocked_ioctl = gup_benchmark_ioctl,
-};
-
-static int gup_benchmark_init(void)
-{
-	debugfs_create_file_unsafe("gup_benchmark", 0600, NULL, NULL,
-				   &gup_benchmark_fops);
-
-	return 0;
-}
-
-late_initcall(gup_benchmark_init);
--- /dev/null
+++ a/mm/gup_test.c
@@ -0,0 +1,210 @@
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/ktime.h>
+#include <linux/debugfs.h>
+
+#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_test)
+#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_test)
+#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_test)
+#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_test)
+#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_test)
+
+struct gup_test {
+	__u64 get_delta_usec;
+	__u64 put_delta_usec;
+	__u64 addr;
+	__u64 size;
+	__u32 nr_pages_per_call;
+	__u32 flags;
+	__u64 expansion[10];	/* For future use */
+};
+
+static void put_back_pages(unsigned int cmd, struct page **pages,
+			   unsigned long nr_pages)
+{
+	unsigned long i;
+
+	switch (cmd) {
+	case GUP_FAST_BENCHMARK:
+	case GUP_BENCHMARK:
+		for (i = 0; i < nr_pages; i++)
+			put_page(pages[i]);
+		break;
+
+	case PIN_FAST_BENCHMARK:
+	case PIN_BENCHMARK:
+	case PIN_LONGTERM_BENCHMARK:
+		unpin_user_pages(pages, nr_pages);
+		break;
+	}
+}
+
+static void verify_dma_pinned(unsigned int cmd, struct page **pages,
+			      unsigned long nr_pages)
+{
+	unsigned long i;
+	struct page *page;
+
+	switch (cmd) {
+	case PIN_FAST_BENCHMARK:
+	case PIN_BENCHMARK:
+	case PIN_LONGTERM_BENCHMARK:
+		for (i = 0; i < nr_pages; i++) {
+			page = pages[i];
+			if (WARN(!page_maybe_dma_pinned(page),
+				 "pages[%lu] is NOT dma-pinned\n", i)) {
+
+				dump_page(page, "gup_test failure");
+				break;
+			}
+		}
+		break;
+	}
+}
+
+static int __gup_test_ioctl(unsigned int cmd,
+		struct gup_test *gup)
+{
+	ktime_t start_time, end_time;
+	unsigned long i, nr_pages, addr, next;
+	int nr;
+	struct page **pages;
+	int ret = 0;
+	bool needs_mmap_lock =
+		cmd != GUP_FAST_BENCHMARK && cmd != PIN_FAST_BENCHMARK;
+
+	if (gup->size > ULONG_MAX)
+		return -EINVAL;
+
+	nr_pages = gup->size / PAGE_SIZE;
+	pages = kvcalloc(nr_pages, sizeof(void *), GFP_KERNEL);
+	if (!pages)
+		return -ENOMEM;
+
+	if (needs_mmap_lock && mmap_read_lock_killable(current->mm)) {
+		ret = -EINTR;
+		goto free_pages;
+	}
+
+	i = 0;
+	nr = gup->nr_pages_per_call;
+	start_time = ktime_get();
+	for (addr = gup->addr; addr < gup->addr + gup->size; addr = next) {
+		if (nr != gup->nr_pages_per_call)
+			break;
+
+		next = addr + nr * PAGE_SIZE;
+		if (next > gup->addr + gup->size) {
+			next = gup->addr + gup->size;
+			nr = (next - addr) / PAGE_SIZE;
+		}
+
+		/* Filter out most gup flags: only allow a tiny subset here: */
+		gup->flags &= FOLL_WRITE;
+
+		switch (cmd) {
+		case GUP_FAST_BENCHMARK:
+			nr = get_user_pages_fast(addr, nr, gup->flags,
+						 pages + i);
+			break;
+		case GUP_BENCHMARK:
+			nr = get_user_pages(addr, nr, gup->flags, pages + i,
+					    NULL);
+			break;
+		case PIN_FAST_BENCHMARK:
+			nr = pin_user_pages_fast(addr, nr, gup->flags,
+						 pages + i);
+			break;
+		case PIN_BENCHMARK:
+			nr = pin_user_pages(addr, nr, gup->flags, pages + i,
+					    NULL);
+			break;
+		case PIN_LONGTERM_BENCHMARK:
+			nr = pin_user_pages(addr, nr,
+					    gup->flags | FOLL_LONGTERM,
+					    pages + i, NULL);
+			break;
+		default:
+			ret = -EINVAL;
+			goto unlock;
+		}
+
+		if (nr <= 0)
+			break;
+		i += nr;
+	}
+	end_time = ktime_get();
+
+	/* Shifting the meaning of nr_pages: now it is actual number pinned: */
+	nr_pages = i;
+
+	gup->get_delta_usec = ktime_us_delta(end_time, start_time);
+	gup->size = addr - gup->addr;
+
+	/*
+	 * Take an un-benchmark-timed moment to verify DMA pinned
+	 * state: print a warning if any non-dma-pinned pages are found:
+	 */
+	verify_dma_pinned(cmd, pages, nr_pages);
+
+	start_time = ktime_get();
+
+	put_back_pages(cmd, pages, nr_pages);
+
+	end_time = ktime_get();
+	gup->put_delta_usec = ktime_us_delta(end_time, start_time);
+
+unlock:
+	if (needs_mmap_lock)
+		mmap_read_unlock(current->mm);
+free_pages:
+	kvfree(pages);
+	return ret;
+}
+
+static long gup_test_ioctl(struct file *filep, unsigned int cmd,
+		unsigned long arg)
+{
+	struct gup_test gup;
+	int ret;
+
+	switch (cmd) {
+	case GUP_FAST_BENCHMARK:
+	case GUP_BENCHMARK:
+	case PIN_FAST_BENCHMARK:
+	case PIN_BENCHMARK:
+	case PIN_LONGTERM_BENCHMARK:
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (copy_from_user(&gup, (void __user *)arg, sizeof(gup)))
+		return -EFAULT;
+
+	ret = __gup_test_ioctl(cmd, &gup);
+	if (ret)
+		return ret;
+
+	if (copy_to_user((void __user *)arg, &gup, sizeof(gup)))
+		return -EFAULT;
+
+	return 0;
+}
+
+static const struct file_operations gup_test_fops = {
+	.open = nonseekable_open,
+	.unlocked_ioctl = gup_test_ioctl,
+};
+
+static int gup_test_init(void)
+{
+	debugfs_create_file_unsafe("gup_test", 0600, NULL, NULL,
+				   &gup_test_fops);
+
+	return 0;
+}
+
+late_initcall(gup_test_init);
--- a/mm/Kconfig~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/mm/Kconfig
@@ -831,13 +831,18 @@ config PERCPU_STATS
 	  information includes global and per chunk statistics, which can
 	  be used to help understand percpu memory usage.
 
-config GUP_BENCHMARK
-	bool "Enable infrastructure for get_user_pages() and related calls benchmarking"
+config GUP_TEST
+	bool "Enable infrastructure for get_user_pages()-related unit tests"
 	help
-	  Provides /sys/kernel/debug/gup_benchmark that helps with testing
-	  performance of get_user_pages() and related calls.
+	  Provides /sys/kernel/debug/gup_test, which in turn provides a way
+	  to make ioctl calls that can launch kernel-based unit tests for
+	  the get_user_pages*() and pin_user_pages*() family of API calls.
 
-	  See tools/testing/selftests/vm/gup_benchmark.c
+	  These tests include benchmark testing of the _fast variants of
+	  get_user_pages*() and pin_user_pages*(), as well as smoke tests of
+	  the non-_fast variants.
+
+	  See tools/testing/selftests/vm/gup_test.c
 
 config GUP_GET_PTE_LOW_HIGH
 	bool
--- a/mm/Makefile~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/mm/Makefile
@@ -90,7 +90,7 @@ obj-$(CONFIG_PAGE_COUNTER) += page_count
 obj-$(CONFIG_MEMCG) += memcontrol.o vmpressure.o
 obj-$(CONFIG_MEMCG_SWAP) += swap_cgroup.o
 obj-$(CONFIG_CGROUP_HUGETLB) += hugetlb_cgroup.o
-obj-$(CONFIG_GUP_BENCHMARK) += gup_benchmark.o
+obj-$(CONFIG_GUP_TEST) += gup_test.o
 obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
 obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o
 obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o
--- a/tools/testing/selftests/vm/config~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/tools/testing/selftests/vm/config
@@ -3,4 +3,4 @@ CONFIG_USERFAULTFD=y
 CONFIG_TEST_VMALLOC=m
 CONFIG_DEVICE_PRIVATE=y
 CONFIG_TEST_HMM=m
-CONFIG_GUP_BENCHMARK=y
+CONFIG_GUP_TEST=y
--- a/tools/testing/selftests/vm/.gitignore~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/tools/testing/selftests/vm/.gitignore
@@ -15,7 +15,7 @@ userfaultfd
 mlock-intersect-test
 mlock-random-test
 virtual_address_range
-gup_benchmark
+gup_test
 va_128TBswitch
 map_fixed_noreplace
 write_to_hugetlbfs
--- a/tools/testing/selftests/vm/gup_benchmark.c
+++ /dev/null
@@ -1,143 +0,0 @@
-#include <fcntl.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-
-#include <sys/ioctl.h>
-#include <sys/mman.h>
-#include <sys/prctl.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-
-#include <linux/types.h>
-
-#define MB (1UL << 20)
-#define PAGE_SIZE sysconf(_SC_PAGESIZE)
-
-#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_benchmark)
-#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_benchmark)
-
-/* Similar to above, but use FOLL_PIN instead of FOLL_GET. */
-#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_benchmark)
-#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_benchmark)
-#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_benchmark)
-
-/* Just the flags we need, copied from mm.h: */
-#define FOLL_WRITE	0x01	/* check pte is writable */
-
-struct gup_benchmark {
-	__u64 get_delta_usec;
-	__u64 put_delta_usec;
-	__u64 addr;
-	__u64 size;
-	__u32 nr_pages_per_call;
-	__u32 flags;
-	__u64 expansion[10];	/* For future use */
-};
-
-int main(int argc, char **argv)
-{
-	struct gup_benchmark gup;
-	unsigned long size = 128 * MB;
-	int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
-	int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
-	char *file = "/dev/zero";
-	char *p;
-
-	while ((opt = getopt(argc, argv, "m:r:n:f:abtTLUuwSH")) != -1) {
-		switch (opt) {
-		case 'a':
-			cmd = PIN_FAST_BENCHMARK;
-			break;
-		case 'b':
-			cmd = PIN_BENCHMARK;
-			break;
-		case 'L':
-			cmd = PIN_LONGTERM_BENCHMARK;
-			break;
-		case 'm':
-			size = atoi(optarg) * MB;
-			break;
-		case 'r':
-			repeats = atoi(optarg);
-			break;
-		case 'n':
-			nr_pages = atoi(optarg);
-			break;
-		case 't':
-			thp = 1;
-			break;
-		case 'T':
-			thp = 0;
-			break;
-		case 'U':
-			cmd = GUP_BENCHMARK;
-			break;
-		case 'u':
-			cmd = GUP_FAST_BENCHMARK;
-			break;
-		case 'w':
-			write = 1;
-			break;
-		case 'f':
-			file = optarg;
-			break;
-		case 'S':
-			flags &= ~MAP_PRIVATE;
-			flags |= MAP_SHARED;
-			break;
-		case 'H':
-			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
-			break;
-		default:
-			return -1;
-		}
-	}
-
-	filed = open(file, O_RDWR|O_CREAT);
-	if (filed < 0) {
-		perror("open");
-		exit(filed);
-	}
-
-	gup.nr_pages_per_call = nr_pages;
-	if (write)
-		gup.flags |= FOLL_WRITE;
-
-	fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
-	if (fd == -1) {
-		perror("open");
-		exit(1);
-	}
-
-	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
-	if (p == MAP_FAILED) {
-		perror("mmap");
-		exit(1);
-	}
-	gup.addr = (unsigned long)p;
-
-	if (thp == 1)
-		madvise(p, size, MADV_HUGEPAGE);
-	else if (thp == 0)
-		madvise(p, size, MADV_NOHUGEPAGE);
-
-	for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
-		p[0] = 0;
-
-	for (i = 0; i < repeats; i++) {
-		gup.size = size;
-		if (ioctl(fd, cmd, &gup)) {
-			perror("ioctl");
-			exit(1);
-		}
-
-		printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
-			gup.put_delta_usec);
-		if (gup.size != size)
-			printf(", truncated (size: %lld)", gup.size);
-		printf("\n");
-	}
-
-	return 0;
-}
--- /dev/null
+++ a/tools/testing/selftests/vm/gup_test.c
@@ -0,0 +1,143 @@
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/prctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#include <linux/types.h>
+
+#define MB (1UL << 20)
+#define PAGE_SIZE sysconf(_SC_PAGESIZE)
+
+#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_benchmark)
+#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_benchmark)
+
+/* Similar to above, but use FOLL_PIN instead of FOLL_GET. */
+#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_benchmark)
+#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_benchmark)
+#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_benchmark)
+
+/* Just the flags we need, copied from mm.h: */
+#define FOLL_WRITE	0x01	/* check pte is writable */
+
+struct gup_benchmark {
+	__u64 get_delta_usec;
+	__u64 put_delta_usec;
+	__u64 addr;
+	__u64 size;
+	__u32 nr_pages_per_call;
+	__u32 flags;
+	__u64 expansion[10];	/* For future use */
+};
+
+int main(int argc, char **argv)
+{
+	struct gup_benchmark gup;
+	unsigned long size = 128 * MB;
+	int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
+	int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
+	char *file = "/dev/zero";
+	char *p;
+
+	while ((opt = getopt(argc, argv, "m:r:n:f:abtTLUuwSH")) != -1) {
+		switch (opt) {
+		case 'a':
+			cmd = PIN_FAST_BENCHMARK;
+			break;
+		case 'b':
+			cmd = PIN_BENCHMARK;
+			break;
+		case 'L':
+			cmd = PIN_LONGTERM_BENCHMARK;
+			break;
+		case 'm':
+			size = atoi(optarg) * MB;
+			break;
+		case 'r':
+			repeats = atoi(optarg);
+			break;
+		case 'n':
+			nr_pages = atoi(optarg);
+			break;
+		case 't':
+			thp = 1;
+			break;
+		case 'T':
+			thp = 0;
+			break;
+		case 'U':
+			cmd = GUP_BENCHMARK;
+			break;
+		case 'u':
+			cmd = GUP_FAST_BENCHMARK;
+			break;
+		case 'w':
+			write = 1;
+			break;
+		case 'f':
+			file = optarg;
+			break;
+		case 'S':
+			flags &= ~MAP_PRIVATE;
+			flags |= MAP_SHARED;
+			break;
+		case 'H':
+			flags |= (MAP_HUGETLB | MAP_ANONYMOUS);
+			break;
+		default:
+			return -1;
+		}
+	}
+
+	filed = open(file, O_RDWR|O_CREAT);
+	if (filed < 0) {
+		perror("open");
+		exit(filed);
+	}
+
+	gup.nr_pages_per_call = nr_pages;
+	if (write)
+		gup.flags |= FOLL_WRITE;
+
+	fd = open("/sys/kernel/debug/gup_benchmark", O_RDWR);
+	if (fd == -1) {
+		perror("open");
+		exit(1);
+	}
+
+	p = mmap(NULL, size, PROT_READ | PROT_WRITE, flags, filed, 0);
+	if (p == MAP_FAILED) {
+		perror("mmap");
+		exit(1);
+	}
+	gup.addr = (unsigned long)p;
+
+	if (thp == 1)
+		madvise(p, size, MADV_HUGEPAGE);
+	else if (thp == 0)
+		madvise(p, size, MADV_NOHUGEPAGE);
+
+	for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
+		p[0] = 0;
+
+	for (i = 0; i < repeats; i++) {
+		gup.size = size;
+		if (ioctl(fd, cmd, &gup)) {
+			perror("ioctl");
+			exit(1);
+		}
+
+		printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
+			gup.put_delta_usec);
+		if (gup.size != size)
+			printf(", truncated (size: %lld)", gup.size);
+		printf("\n");
+	}
+
+	return 0;
+}
--- a/tools/testing/selftests/vm/Makefile~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/tools/testing/selftests/vm/Makefile
@@ -23,7 +23,7 @@ MAKEFLAGS += --no-builtin-rules
 CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)
 LDLIBS = -lrt
 TEST_GEN_FILES = compaction_test
-TEST_GEN_FILES += gup_benchmark
+TEST_GEN_FILES += gup_test
 TEST_GEN_FILES += hmm-tests
 TEST_GEN_FILES += hugepage-mmap
 TEST_GEN_FILES += hugepage-shm
--- a/tools/testing/selftests/vm/run_vmtests~mm-gup_benchmark-rename-to-mm-gup_test
+++ a/tools/testing/selftests/vm/run_vmtests
@@ -124,9 +124,9 @@ else
 fi
 
 echo "--------------------------------------------"
-echo "running 'gup_benchmark -U' (normal/slow gup)"
+echo "running 'gup_test -U' (normal/slow gup)"
 echo "--------------------------------------------"
-./gup_benchmark -U
+./gup_test -U
 if [ $? -ne 0 ]; then
 	echo "[FAIL]"
 	exitcode=1
@@ -135,9 +135,9 @@ else
 fi
 
 echo "------------------------------------------"
-echo "running gup_benchmark -b (pin_user_pages)"
+echo "running gup_test -b (pin_user_pages)"
 echo "------------------------------------------"
-./gup_benchmark -b
+./gup_test -b
 if [ $? -ne 0 ]; then
 	echo "[FAIL]"
 	exitcode=1
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-17 23:13 incoming Andrew Morton
                   ` (14 preceding siblings ...)
  2020-10-17 23:14 ` [patch 15/40] mm/gup_benchmark: rename to mm/gup_test Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-18 16:18   ` Linus Torvalds
  2020-10-17 23:14 ` [patch 17/40] selftests/vm: rename run_vmtests --> run_vmtests.sh Andrew Morton
                   ` (23 subsequent siblings)
  39 siblings, 1 reply; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: use a common gup_test.h

Avoid the need to copy-paste the gup_test ioctl commands and the struct
gup_test definition, between the kernel and the user space application, by
providing a new header file for these.  This allows easier and safer
adding of new ioctl calls, as well as reducing the overall line count.

Details: The header file has to be able to compile independently, because
of the arguably unfortunate way that the Makefile is written: the Makefile
tries to build all of its prerequisites, when really it should be only
building the .c files, and leaving the other prerequisites (LOCAL_HDRS) as
pure dependencies.

That Makefile limitation is probably not worth fixing, but it explains why
one of the includes had to be moved into the new header file.

Also: simplify the ioctl struct (struct gup_test), by deleting the unused
__expansion[10] field.  This sort of thing is what you might see in a
stable ABI, but this low-level, kernel-developer-oriented selftests/vm
system is very much not subject to ABI stability.  So "expansion" and
"reserved" fields are unnecessary here.

Link: https://lkml.kernel.org/r/20200929212747.251804-3-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/gup_test.c                         |   17 +----------------
 mm/gup_test.h                         |   22 ++++++++++++++++++++++
 tools/testing/selftests/vm/Makefile   |    2 ++
 tools/testing/selftests/vm/gup_test.c |   22 +---------------------
 4 files changed, 26 insertions(+), 37 deletions(-)

--- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
+++ a/mm/gup_test.c
@@ -4,22 +4,7 @@
 #include <linux/uaccess.h>
 #include <linux/ktime.h>
 #include <linux/debugfs.h>
-
-#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_test)
-#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_test)
-#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_test)
-#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_test)
-#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_test)
-
-struct gup_test {
-	__u64 get_delta_usec;
-	__u64 put_delta_usec;
-	__u64 addr;
-	__u64 size;
-	__u32 nr_pages_per_call;
-	__u32 flags;
-	__u64 expansion[10];	/* For future use */
-};
+#include "../../../../mm/gup_test.h"
 
 static void put_back_pages(unsigned int cmd, struct page **pages,
 			   unsigned long nr_pages)
--- /dev/null
+++ a/mm/gup_test.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __GUP_TEST_H
+#define __GUP_TEST_H
+
+#include <linux/types.h>
+
+#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_test)
+#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_test)
+#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_test)
+#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_test)
+#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_test)
+
+struct gup_test {
+	__u64 get_delta_usec;
+	__u64 put_delta_usec;
+	__u64 addr;
+	__u64 size;
+	__u32 nr_pages_per_call;
+	__u32 flags;
+};
+
+#endif	/* __GUP_TEST_H */
--- a/tools/testing/selftests/vm/gup_test.c~selftests-vm-use-a-common-gup_testh
+++ a/tools/testing/selftests/vm/gup_test.c
@@ -2,39 +2,19 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
-
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <sys/prctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
-
-#include <linux/types.h>
+#include "../../../../mm/gup_test.h"
 
 #define MB (1UL << 20)
 #define PAGE_SIZE sysconf(_SC_PAGESIZE)
 
-#define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_benchmark)
-#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_benchmark)
-
-/* Similar to above, but use FOLL_PIN instead of FOLL_GET. */
-#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_benchmark)
-#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_benchmark)
-#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_benchmark)
-
 /* Just the flags we need, copied from mm.h: */
 #define FOLL_WRITE	0x01	/* check pte is writable */
 
-struct gup_benchmark {
-	__u64 get_delta_usec;
-	__u64 put_delta_usec;
-	__u64 addr;
-	__u64 size;
-	__u32 nr_pages_per_call;
-	__u32 flags;
-	__u64 expansion[10];	/* For future use */
-};
-
 int main(int argc, char **argv)
 {
 	struct gup_benchmark gup;
--- a/tools/testing/selftests/vm/Makefile~selftests-vm-use-a-common-gup_testh
+++ a/tools/testing/selftests/vm/Makefile
@@ -130,3 +130,5 @@ endif
 $(OUTPUT)/userfaultfd: LDLIBS += -lpthread
 
 $(OUTPUT)/mlock-random-test: LDLIBS += -lcap
+
+$(OUTPUT)/gup_test: ../../../../mm/gup_test.h
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 17/40] selftests/vm: rename run_vmtests --> run_vmtests.sh
  2020-10-17 23:13 incoming Andrew Morton
                   ` (15 preceding siblings ...)
  2020-10-17 23:14 ` [patch 16/40] selftests/vm: use a common gup_test.h Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 18/40] selftests/vm: minor cleanup: Makefile and gup_test.c Andrew Morton
                   ` (22 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: rename run_vmtests --> run_vmtests.sh

Rename to *.sh, in order to match the conventions of all of the other
items in selftest/vm.

The only reason not to use a .sh suffix a shell script like this, might be
to make it look more like a normal program, but that's not an issue here.

Link: https://lkml.kernel.org/r/20200929212747.251804-4-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/vm/Makefile       |    2 
 tools/testing/selftests/vm/run_vmtests    |  326 --------------------
 tools/testing/selftests/vm/run_vmtests.sh |  326 ++++++++++++++++++++
 3 files changed, 327 insertions(+), 327 deletions(-)

--- a/tools/testing/selftests/vm/Makefile~selftests-vm-rename-run_vmtests-run_vmtestssh
+++ a/tools/testing/selftests/vm/Makefile
@@ -69,7 +69,7 @@ TEST_GEN_FILES += virtual_address_range
 TEST_GEN_FILES += write_to_hugetlbfs
 endif
 
-TEST_PROGS := run_vmtests
+TEST_PROGS := run_vmtests.sh
 
 TEST_FILES := test_vmalloc.sh
 
--- a/tools/testing/selftests/vm/run_vmtests
+++ /dev/null
@@ -1,326 +0,0 @@
-#!/bin/bash
-# SPDX-License-Identifier: GPL-2.0
-#please run as root
-
-# Kselftest framework requirement - SKIP code is 4.
-ksft_skip=4
-
-mnt=./huge
-exitcode=0
-
-#get huge pagesize and freepages from /proc/meminfo
-while read name size unit; do
-	if [ "$name" = "HugePages_Free:" ]; then
-		freepgs=$size
-	fi
-	if [ "$name" = "Hugepagesize:" ]; then
-		hpgsize_KB=$size
-	fi
-done < /proc/meminfo
-
-# Simple hugetlbfs tests have a hardcoded minimum requirement of
-# huge pages totaling 256MB (262144KB) in size.  The userfaultfd
-# hugetlb test requires a minimum of 2 * nr_cpus huge pages.  Take
-# both of these requirements into account and attempt to increase
-# number of huge pages available.
-nr_cpus=$(nproc)
-hpgsize_MB=$((hpgsize_KB / 1024))
-half_ufd_size_MB=$((((nr_cpus * hpgsize_MB + 127) / 128) * 128))
-needmem_KB=$((half_ufd_size_MB * 2 * 1024))
-
-#set proper nr_hugepages
-if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then
-	nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
-	needpgs=$((needmem_KB / hpgsize_KB))
-	tries=2
-	while [ $tries -gt 0 ] && [ $freepgs -lt $needpgs ]; do
-		lackpgs=$(( $needpgs - $freepgs ))
-		echo 3 > /proc/sys/vm/drop_caches
-		echo $(( $lackpgs + $nr_hugepgs )) > /proc/sys/vm/nr_hugepages
-		if [ $? -ne 0 ]; then
-			echo "Please run this test as root"
-			exit $ksft_skip
-		fi
-		while read name size unit; do
-			if [ "$name" = "HugePages_Free:" ]; then
-				freepgs=$size
-			fi
-		done < /proc/meminfo
-		tries=$((tries - 1))
-	done
-	if [ $freepgs -lt $needpgs ]; then
-		printf "Not enough huge pages available (%d < %d)\n" \
-		       $freepgs $needpgs
-		exit 1
-	fi
-else
-	echo "no hugetlbfs support in kernel?"
-	exit 1
-fi
-
-#filter 64bit architectures
-ARCH64STR="arm64 ia64 mips64 parisc64 ppc64 ppc64le riscv64 s390x sh64 sparc64 x86_64"
-if [ -z $ARCH ]; then
-  ARCH=`uname -m 2>/dev/null | sed -e 's/aarch64.*/arm64/'`
-fi
-VADDR64=0
-echo "$ARCH64STR" | grep $ARCH && VADDR64=1
-
-mkdir $mnt
-mount -t hugetlbfs none $mnt
-
-echo "---------------------"
-echo "running hugepage-mmap"
-echo "---------------------"
-./hugepage-mmap
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-shmmax=`cat /proc/sys/kernel/shmmax`
-shmall=`cat /proc/sys/kernel/shmall`
-echo 268435456 > /proc/sys/kernel/shmmax
-echo 4194304 > /proc/sys/kernel/shmall
-echo "--------------------"
-echo "running hugepage-shm"
-echo "--------------------"
-./hugepage-shm
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-echo $shmmax > /proc/sys/kernel/shmmax
-echo $shmall > /proc/sys/kernel/shmall
-
-echo "-------------------"
-echo "running map_hugetlb"
-echo "-------------------"
-./map_hugetlb
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "NOTE: The above hugetlb tests provide minimal coverage.  Use"
-echo "      https://github.com/libhugetlbfs/libhugetlbfs.git for"
-echo "      hugetlb regression testing."
-
-echo "---------------------------"
-echo "running map_fixed_noreplace"
-echo "---------------------------"
-./map_fixed_noreplace
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "--------------------------------------------"
-echo "running 'gup_test -U' (normal/slow gup)"
-echo "--------------------------------------------"
-./gup_test -U
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "------------------------------------------"
-echo "running gup_test -b (pin_user_pages)"
-echo "------------------------------------------"
-./gup_test -b
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "-------------------"
-echo "running userfaultfd"
-echo "-------------------"
-./userfaultfd anon 128 32
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "---------------------------"
-echo "running userfaultfd_hugetlb"
-echo "---------------------------"
-# Test requires source and destination huge pages.  Size of source
-# (half_ufd_size_MB) is passed as argument to test.
-./userfaultfd hugetlb $half_ufd_size_MB 32 $mnt/ufd_test_file
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-rm -f $mnt/ufd_test_file
-
-echo "-------------------------"
-echo "running userfaultfd_shmem"
-echo "-------------------------"
-./userfaultfd shmem 128 32
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-#cleanup
-umount $mnt
-rm -rf $mnt
-echo $nr_hugepgs > /proc/sys/vm/nr_hugepages
-
-echo "-----------------------"
-echo "running compaction_test"
-echo "-----------------------"
-./compaction_test
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "----------------------"
-echo "running on-fault-limit"
-echo "----------------------"
-sudo -u nobody ./on-fault-limit
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "--------------------"
-echo "running map_populate"
-echo "--------------------"
-./map_populate
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "-------------------------"
-echo "running mlock-random-test"
-echo "-------------------------"
-./mlock-random-test
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "--------------------"
-echo "running mlock2-tests"
-echo "--------------------"
-./mlock2-tests
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "-----------------"
-echo "running thuge-gen"
-echo "-----------------"
-./thuge-gen
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-if [ $VADDR64 -ne 0 ]; then
-echo "-----------------------------"
-echo "running virtual_address_range"
-echo "-----------------------------"
-./virtual_address_range
-if [ $? -ne 0 ]; then
-	echo "[FAIL]"
-	exitcode=1
-else
-	echo "[PASS]"
-fi
-
-echo "-----------------------------"
-echo "running virtual address 128TB switch test"
-echo "-----------------------------"
-./va_128TBswitch
-if [ $? -ne 0 ]; then
-    echo "[FAIL]"
-    exitcode=1
-else
-    echo "[PASS]"
-fi
-fi # VADDR64
-
-echo "------------------------------------"
-echo "running vmalloc stability smoke test"
-echo "------------------------------------"
-./test_vmalloc.sh smoke
-ret_val=$?
-
-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
-
-echo "------------------------------------"
-echo "running MREMAP_DONTUNMAP smoke test"
-echo "------------------------------------"
-./mremap_dontunmap
-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
-
-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 $exitcode
--- /dev/null
+++ a/tools/testing/selftests/vm/run_vmtests.sh
@@ -0,0 +1,326 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#please run as root
+
+# Kselftest framework requirement - SKIP code is 4.
+ksft_skip=4
+
+mnt=./huge
+exitcode=0
+
+#get huge pagesize and freepages from /proc/meminfo
+while read name size unit; do
+	if [ "$name" = "HugePages_Free:" ]; then
+		freepgs=$size
+	fi
+	if [ "$name" = "Hugepagesize:" ]; then
+		hpgsize_KB=$size
+	fi
+done < /proc/meminfo
+
+# Simple hugetlbfs tests have a hardcoded minimum requirement of
+# huge pages totaling 256MB (262144KB) in size.  The userfaultfd
+# hugetlb test requires a minimum of 2 * nr_cpus huge pages.  Take
+# both of these requirements into account and attempt to increase
+# number of huge pages available.
+nr_cpus=$(nproc)
+hpgsize_MB=$((hpgsize_KB / 1024))
+half_ufd_size_MB=$((((nr_cpus * hpgsize_MB + 127) / 128) * 128))
+needmem_KB=$((half_ufd_size_MB * 2 * 1024))
+
+#set proper nr_hugepages
+if [ -n "$freepgs" ] && [ -n "$hpgsize_KB" ]; then
+	nr_hugepgs=`cat /proc/sys/vm/nr_hugepages`
+	needpgs=$((needmem_KB / hpgsize_KB))
+	tries=2
+	while [ $tries -gt 0 ] && [ $freepgs -lt $needpgs ]; do
+		lackpgs=$(( $needpgs - $freepgs ))
+		echo 3 > /proc/sys/vm/drop_caches
+		echo $(( $lackpgs + $nr_hugepgs )) > /proc/sys/vm/nr_hugepages
+		if [ $? -ne 0 ]; then
+			echo "Please run this test as root"
+			exit $ksft_skip
+		fi
+		while read name size unit; do
+			if [ "$name" = "HugePages_Free:" ]; then
+				freepgs=$size
+			fi
+		done < /proc/meminfo
+		tries=$((tries - 1))
+	done
+	if [ $freepgs -lt $needpgs ]; then
+		printf "Not enough huge pages available (%d < %d)\n" \
+		       $freepgs $needpgs
+		exit 1
+	fi
+else
+	echo "no hugetlbfs support in kernel?"
+	exit 1
+fi
+
+#filter 64bit architectures
+ARCH64STR="arm64 ia64 mips64 parisc64 ppc64 ppc64le riscv64 s390x sh64 sparc64 x86_64"
+if [ -z $ARCH ]; then
+  ARCH=`uname -m 2>/dev/null | sed -e 's/aarch64.*/arm64/'`
+fi
+VADDR64=0
+echo "$ARCH64STR" | grep $ARCH && VADDR64=1
+
+mkdir $mnt
+mount -t hugetlbfs none $mnt
+
+echo "---------------------"
+echo "running hugepage-mmap"
+echo "---------------------"
+./hugepage-mmap
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+shmmax=`cat /proc/sys/kernel/shmmax`
+shmall=`cat /proc/sys/kernel/shmall`
+echo 268435456 > /proc/sys/kernel/shmmax
+echo 4194304 > /proc/sys/kernel/shmall
+echo "--------------------"
+echo "running hugepage-shm"
+echo "--------------------"
+./hugepage-shm
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+echo $shmmax > /proc/sys/kernel/shmmax
+echo $shmall > /proc/sys/kernel/shmall
+
+echo "-------------------"
+echo "running map_hugetlb"
+echo "-------------------"
+./map_hugetlb
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "NOTE: The above hugetlb tests provide minimal coverage.  Use"
+echo "      https://github.com/libhugetlbfs/libhugetlbfs.git for"
+echo "      hugetlb regression testing."
+
+echo "---------------------------"
+echo "running map_fixed_noreplace"
+echo "---------------------------"
+./map_fixed_noreplace
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "--------------------------------------------"
+echo "running 'gup_test -U' (normal/slow gup)"
+echo "--------------------------------------------"
+./gup_test -U
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "------------------------------------------"
+echo "running gup_test -b (pin_user_pages)"
+echo "------------------------------------------"
+./gup_test -b
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "-------------------"
+echo "running userfaultfd"
+echo "-------------------"
+./userfaultfd anon 128 32
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "---------------------------"
+echo "running userfaultfd_hugetlb"
+echo "---------------------------"
+# Test requires source and destination huge pages.  Size of source
+# (half_ufd_size_MB) is passed as argument to test.
+./userfaultfd hugetlb $half_ufd_size_MB 32 $mnt/ufd_test_file
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+rm -f $mnt/ufd_test_file
+
+echo "-------------------------"
+echo "running userfaultfd_shmem"
+echo "-------------------------"
+./userfaultfd shmem 128 32
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+#cleanup
+umount $mnt
+rm -rf $mnt
+echo $nr_hugepgs > /proc/sys/vm/nr_hugepages
+
+echo "-----------------------"
+echo "running compaction_test"
+echo "-----------------------"
+./compaction_test
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "----------------------"
+echo "running on-fault-limit"
+echo "----------------------"
+sudo -u nobody ./on-fault-limit
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "--------------------"
+echo "running map_populate"
+echo "--------------------"
+./map_populate
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "-------------------------"
+echo "running mlock-random-test"
+echo "-------------------------"
+./mlock-random-test
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "--------------------"
+echo "running mlock2-tests"
+echo "--------------------"
+./mlock2-tests
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "-----------------"
+echo "running thuge-gen"
+echo "-----------------"
+./thuge-gen
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+if [ $VADDR64 -ne 0 ]; then
+echo "-----------------------------"
+echo "running virtual_address_range"
+echo "-----------------------------"
+./virtual_address_range
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "-----------------------------"
+echo "running virtual address 128TB switch test"
+echo "-----------------------------"
+./va_128TBswitch
+if [ $? -ne 0 ]; then
+    echo "[FAIL]"
+    exitcode=1
+else
+    echo "[PASS]"
+fi
+fi # VADDR64
+
+echo "------------------------------------"
+echo "running vmalloc stability smoke test"
+echo "------------------------------------"
+./test_vmalloc.sh smoke
+ret_val=$?
+
+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
+
+echo "------------------------------------"
+echo "running MREMAP_DONTUNMAP smoke test"
+echo "------------------------------------"
+./mremap_dontunmap
+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
+
+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
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 18/40] selftests/vm: minor cleanup: Makefile and gup_test.c
  2020-10-17 23:13 incoming Andrew Morton
                   ` (16 preceding siblings ...)
  2020-10-17 23:14 ` [patch 17/40] selftests/vm: rename run_vmtests --> run_vmtests.sh Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 19/40] selftests/vm: only some gup_test items are really benchmarks Andrew Morton
                   ` (21 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: minor cleanup: Makefile and gup_test.c

A few cleanups that don't deserve separate patches, but that also should
not clutter up other functional changes:

1. Remove an unnecessary #include <prctl.h>

2. Restore the sorted order of TEST_GEN_FILES.

3. Add -lpthread to the common LDLIBS, as it is harmless and several
   tests use it. This gets rid of one special rule already.

Link: https://lkml.kernel.org/r/20200929212747.251804-5-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/vm/Makefile   |   10 ++++------
 tools/testing/selftests/vm/gup_test.c |    1 -
 2 files changed, 4 insertions(+), 7 deletions(-)

--- a/tools/testing/selftests/vm/gup_test.c~selftests-vm-minor-cleanup-makefile-and-gup_testc
+++ a/tools/testing/selftests/vm/gup_test.c
@@ -4,7 +4,6 @@
 #include <unistd.h>
 #include <sys/ioctl.h>
 #include <sys/mman.h>
-#include <sys/prctl.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include "../../../../mm/gup_test.h"
--- a/tools/testing/selftests/vm/Makefile~selftests-vm-minor-cleanup-makefile-and-gup_testc
+++ a/tools/testing/selftests/vm/Makefile
@@ -21,14 +21,15 @@ MACHINE ?= $(shell echo $(uname_M) | sed
 MAKEFLAGS += --no-builtin-rules
 
 CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)
-LDLIBS = -lrt
+LDLIBS = -lrt -lpthread
 TEST_GEN_FILES = compaction_test
 TEST_GEN_FILES += gup_test
 TEST_GEN_FILES += hmm-tests
 TEST_GEN_FILES += hugepage-mmap
 TEST_GEN_FILES += hugepage-shm
-TEST_GEN_FILES += map_hugetlb
+TEST_GEN_FILES += khugepaged
 TEST_GEN_FILES += map_fixed_noreplace
+TEST_GEN_FILES += map_hugetlb
 TEST_GEN_FILES += map_populate
 TEST_GEN_FILES += mlock-random-test
 TEST_GEN_FILES += mlock2-tests
@@ -37,7 +38,6 @@ TEST_GEN_FILES += on-fault-limit
 TEST_GEN_FILES += thuge-gen
 TEST_GEN_FILES += transhuge-stress
 TEST_GEN_FILES += userfaultfd
-TEST_GEN_FILES += khugepaged
 
 ifeq ($(ARCH),x86_64)
 CAN_BUILD_I386 := $(shell ./../x86/check_cc.sh $(CC) ../x86/trivial_32bit_program.c -m32)
@@ -76,7 +76,7 @@ TEST_FILES := test_vmalloc.sh
 KSFT_KHDR_INSTALL := 1
 include ../lib.mk
 
-$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs -lpthread
+$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs
 
 ifeq ($(ARCH),x86_64)
 BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
@@ -127,8 +127,6 @@ warn_32bit_failure:
 endif
 endif
 
-$(OUTPUT)/userfaultfd: LDLIBS += -lpthread
-
 $(OUTPUT)/mlock-random-test: LDLIBS += -lcap
 
 $(OUTPUT)/gup_test: ../../../../mm/gup_test.h
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 19/40] selftests/vm: only some gup_test items are really benchmarks
  2020-10-17 23:13 incoming Andrew Morton
                   ` (17 preceding siblings ...)
  2020-10-17 23:14 ` [patch 18/40] selftests/vm: minor cleanup: Makefile and gup_test.c Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 20/40] selftests/vm: gup_test: introduce the dump_pages() sub-test Andrew Morton
                   ` (20 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: only some gup_test items are really benchmarks

Therefore, some minor cleanup and improvements are in order:

1. Rename the other items appropriately.

2. Stop reporting timing information on the non-benchmark items. It's
   still being recorded and is available, but there's no point in
   cluttering up the report with data that no one reasonably needs to
   check.

3. Don't do iterations, for non-benchmark items.

4. Print out a shorter, more appropriate report for the non-benchmark
   tests.

5. Add the command that was run, to the report. This really helps, as
   there are quite a lot of options now.

Link: https://lkml.kernel.org/r/20200929212747.251804-6-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 Documentation/core-api/pin_user_pages.rst |    2 
 mm/gup_test.c                             |   14 ++---
 mm/gup_test.h                             |    8 +--
 tools/testing/selftests/vm/gup_test.c     |   47 ++++++++++++++++----
 4 files changed, 51 insertions(+), 20 deletions(-)

--- a/Documentation/core-api/pin_user_pages.rst~selftests-vm-only-some-gup_test-items-are-really-benchmarks
+++ a/Documentation/core-api/pin_user_pages.rst
@@ -226,7 +226,7 @@ This file::
 has the following new calls to exercise the new pin*() wrapper functions:
 
 * PIN_FAST_BENCHMARK (./gup_test -a)
-* PIN_BENCHMARK (./gup_test -b)
+* PIN_BASIC_TEST (./gup_test -b)
 
 You can monitor how many total dma-pinned pages have been acquired and released
 since the system was booted, via two new /proc/vmstat entries: ::
--- a/mm/gup_test.c~selftests-vm-only-some-gup_test-items-are-really-benchmarks
+++ a/mm/gup_test.c
@@ -13,13 +13,13 @@ static void put_back_pages(unsigned int
 
 	switch (cmd) {
 	case GUP_FAST_BENCHMARK:
-	case GUP_BENCHMARK:
+	case GUP_BASIC_TEST:
 		for (i = 0; i < nr_pages; i++)
 			put_page(pages[i]);
 		break;
 
 	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
+	case PIN_BASIC_TEST:
 	case PIN_LONGTERM_BENCHMARK:
 		unpin_user_pages(pages, nr_pages);
 		break;
@@ -34,7 +34,7 @@ static void verify_dma_pinned(unsigned i
 
 	switch (cmd) {
 	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
+	case PIN_BASIC_TEST:
 	case PIN_LONGTERM_BENCHMARK:
 		for (i = 0; i < nr_pages; i++) {
 			page = pages[i];
@@ -94,7 +94,7 @@ static int __gup_test_ioctl(unsigned int
 			nr = get_user_pages_fast(addr, nr, gup->flags,
 						 pages + i);
 			break;
-		case GUP_BENCHMARK:
+		case GUP_BASIC_TEST:
 			nr = get_user_pages(addr, nr, gup->flags, pages + i,
 					    NULL);
 			break;
@@ -102,7 +102,7 @@ static int __gup_test_ioctl(unsigned int
 			nr = pin_user_pages_fast(addr, nr, gup->flags,
 						 pages + i);
 			break;
-		case PIN_BENCHMARK:
+		case PIN_BASIC_TEST:
 			nr = pin_user_pages(addr, nr, gup->flags, pages + i,
 					    NULL);
 			break;
@@ -157,10 +157,10 @@ static long gup_test_ioctl(struct file *
 
 	switch (cmd) {
 	case GUP_FAST_BENCHMARK:
-	case GUP_BENCHMARK:
 	case PIN_FAST_BENCHMARK:
-	case PIN_BENCHMARK:
 	case PIN_LONGTERM_BENCHMARK:
+	case GUP_BASIC_TEST:
+	case PIN_BASIC_TEST:
 		break;
 	default:
 		return -EINVAL;
--- a/mm/gup_test.h~selftests-vm-only-some-gup_test-items-are-really-benchmarks
+++ a/mm/gup_test.h
@@ -5,10 +5,10 @@
 #include <linux/types.h>
 
 #define GUP_FAST_BENCHMARK	_IOWR('g', 1, struct gup_test)
-#define GUP_BENCHMARK		_IOWR('g', 2, struct gup_test)
-#define PIN_FAST_BENCHMARK	_IOWR('g', 3, struct gup_test)
-#define PIN_BENCHMARK		_IOWR('g', 4, struct gup_test)
-#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 5, struct gup_test)
+#define PIN_FAST_BENCHMARK	_IOWR('g', 2, struct gup_test)
+#define PIN_LONGTERM_BENCHMARK	_IOWR('g', 3, struct gup_test)
+#define GUP_BASIC_TEST		_IOWR('g', 4, struct gup_test)
+#define PIN_BASIC_TEST		_IOWR('g', 5, struct gup_test)
 
 struct gup_test {
 	__u64 get_delta_usec;
--- a/tools/testing/selftests/vm/gup_test.c~selftests-vm-only-some-gup_test-items-are-really-benchmarks
+++ a/tools/testing/selftests/vm/gup_test.c
@@ -14,12 +14,30 @@
 /* Just the flags we need, copied from mm.h: */
 #define FOLL_WRITE	0x01	/* check pte is writable */
 
+static char *cmd_to_str(unsigned long cmd)
+{
+	switch (cmd) {
+	case GUP_FAST_BENCHMARK:
+		return "GUP_FAST_BENCHMARK";
+	case PIN_FAST_BENCHMARK:
+		return "PIN_FAST_BENCHMARK";
+	case PIN_LONGTERM_BENCHMARK:
+		return "PIN_LONGTERM_BENCHMARK";
+	case GUP_BASIC_TEST:
+		return "GUP_BASIC_TEST";
+	case PIN_BASIC_TEST:
+		return "PIN_BASIC_TEST";
+	}
+	return "Unknown command";
+}
+
 int main(int argc, char **argv)
 {
 	struct gup_benchmark gup;
 	unsigned long size = 128 * MB;
 	int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
-	int cmd = GUP_FAST_BENCHMARK, flags = MAP_PRIVATE;
+	int cmd = GUP_FAST_BENCHMARK;
+	int flags = MAP_PRIVATE;
 	char *file = "/dev/zero";
 	char *p;
 
@@ -29,7 +47,7 @@ int main(int argc, char **argv)
 			cmd = PIN_FAST_BENCHMARK;
 			break;
 		case 'b':
-			cmd = PIN_BENCHMARK;
+			cmd = PIN_BASIC_TEST;
 			break;
 		case 'L':
 			cmd = PIN_LONGTERM_BENCHMARK;
@@ -50,7 +68,7 @@ int main(int argc, char **argv)
 			thp = 0;
 			break;
 		case 'U':
-			cmd = GUP_BENCHMARK;
+			cmd = GUP_BASIC_TEST;
 			break;
 		case 'u':
 			cmd = GUP_FAST_BENCHMARK;
@@ -104,18 +122,31 @@ int main(int argc, char **argv)
 	for (; (unsigned long)p < gup.addr + size; p += PAGE_SIZE)
 		p[0] = 0;
 
-	for (i = 0; i < repeats; i++) {
+	/* Only report timing information on the *_BENCHMARK commands: */
+	if ((cmd == PIN_FAST_BENCHMARK) || (cmd == GUP_FAST_BENCHMARK) ||
+	     (cmd == PIN_LONGTERM_BENCHMARK)) {
+		for (i = 0; i < repeats; i++) {
+			gup.size = size;
+			if (ioctl(fd, cmd, &gup))
+				perror("ioctl"), exit(1);
+
+			printf("%s: Time: get:%lld put:%lld us",
+			       cmd_to_str(cmd), gup.get_delta_usec,
+			       gup.put_delta_usec);
+			if (gup.size != size)
+				printf(", truncated (size: %lld)", gup.size);
+			printf("\n");
+		}
+	} else {
 		gup.size = size;
 		if (ioctl(fd, cmd, &gup)) {
 			perror("ioctl");
 			exit(1);
 		}
 
-		printf("Time: get:%lld put:%lld us", gup.get_delta_usec,
-			gup.put_delta_usec);
+		printf("%s: done\n", cmd_to_str(cmd));
 		if (gup.size != size)
-			printf(", truncated (size: %lld)", gup.size);
-		printf("\n");
+			printf("Truncated (size: %lld)\n", gup.size);
 	}
 
 	return 0;
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 20/40] selftests/vm: gup_test: introduce the dump_pages() sub-test
  2020-10-17 23:13 incoming Andrew Morton
                   ` (18 preceding siblings ...)
  2020-10-17 23:14 ` [patch 19/40] selftests/vm: only some gup_test items are really benchmarks Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 21/40] selftests/vm: run_vmtests.sh: update and clean up gup_test invocation Andrew Morton
                   ` (19 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: gup_test: introduce the dump_pages() sub-test

For quite a while, I was doing a quick hack to gup_test.c (previously,
gup_benchmark.c) whenever I wanted to try out my changes to dump_page(). 
This makes that hack unnecessary, and instead allows anyone to easily get
the same coverage from a user space program.  That saves a lot of time
because you don't have to change the kernel, in order to test different
pages and options.

The new sub-test takes advantage of the existing gup_test infrastructure,
which already provides a simple user space program, some allocated user
space pages, an ioctl call, pinning of those pages (via either
get_user_pages or pin_user_pages) and a corresponding kernel-side test
invocation.  There's not much more required, mainly just a couple of
inputs from the user.

In fact, the new test re-uses the existing command line options in order
to get various helpful combinations (THP or normal, _fast or slow gup, gup
vs.  pup, and more).

New command line options are: which pages to dump, and what type of
"get/pin" to use.

In order to figure out which pages to dump, the logic is:

* If the user doesn't specify anything, the page 0 (the first page in
  the address range that the program sets up for testing) is dumped.

* Or, the user can type up to 8 page indices anywhere on the command
  line.  If you type more than 8, then it uses the first 8 and ignores the
  remaining items.

For example:

    ./gup_test -ct -F 1 0 19 0x1000

Meaning:
    -c:          dump pages sub-test
    -t:          use THP pages
    -F 1:        use pin_user_pages() instead of get_user_pages()
    0 19 0x1000: dump pages 0, 19, and 4096
Link: https://lkml.kernel.org/r/20200929212747.251804-7-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/Kconfig                            |    6 ++
 mm/gup_test.c                         |   54 +++++++++++++++++++++++-
 mm/gup_test.h                         |   10 ++++
 tools/testing/selftests/vm/gup_test.c |   47 +++++++++++++++++++-
 4 files changed, 112 insertions(+), 5 deletions(-)

--- a/mm/gup_test.c~selftests-vm-gup_test-introduce-the-dump_pages-sub-test
+++ a/mm/gup_test.c
@@ -7,7 +7,7 @@
 #include "../../../../mm/gup_test.h"
 
 static void put_back_pages(unsigned int cmd, struct page **pages,
-			   unsigned long nr_pages)
+			   unsigned long nr_pages, unsigned int gup_test_flags)
 {
 	unsigned long i;
 
@@ -23,6 +23,15 @@ static void put_back_pages(unsigned int
 	case PIN_LONGTERM_BENCHMARK:
 		unpin_user_pages(pages, nr_pages);
 		break;
+	case DUMP_USER_PAGES_TEST:
+		if (gup_test_flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN) {
+			unpin_user_pages(pages, nr_pages);
+		} else {
+			for (i = 0; i < nr_pages; i++)
+				put_page(pages[i]);
+
+		}
+		break;
 	}
 }
 
@@ -49,6 +58,37 @@ static void verify_dma_pinned(unsigned i
 	}
 }
 
+static void dump_pages_test(struct gup_test *gup, struct page **pages,
+			    unsigned long nr_pages)
+{
+	unsigned int index_to_dump;
+	unsigned int i;
+
+	/*
+	 * Zero out any user-supplied page index that is out of range. Remember:
+	 * .which_pages[] contains a 1-based set of page indices.
+	 */
+	for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) {
+		if (gup->which_pages[i] > nr_pages) {
+			pr_warn("ZEROING due to out of range: .which_pages[%u]: %u\n",
+				i, gup->which_pages[i]);
+			gup->which_pages[i] = 0;
+		}
+	}
+
+	for (i = 0; i < GUP_TEST_MAX_PAGES_TO_DUMP; i++) {
+		index_to_dump = gup->which_pages[i];
+
+		if (index_to_dump) {
+			index_to_dump--; // Decode from 1-based, to 0-based
+			pr_info("---- page #%u, starting from user virt addr: 0x%llx\n",
+				index_to_dump, gup->addr);
+			dump_page(pages[index_to_dump],
+				  "gup_test: dump_pages() test");
+		}
+	}
+}
+
 static int __gup_test_ioctl(unsigned int cmd,
 		struct gup_test *gup)
 {
@@ -111,6 +151,14 @@ static int __gup_test_ioctl(unsigned int
 					    gup->flags | FOLL_LONGTERM,
 					    pages + i, NULL);
 			break;
+		case DUMP_USER_PAGES_TEST:
+			if (gup->flags & GUP_TEST_FLAG_DUMP_PAGES_USE_PIN)
+				nr = pin_user_pages(addr, nr, gup->flags,
+						    pages + i, NULL);
+			else
+				nr = get_user_pages(addr, nr, gup->flags,
+						    pages + i, NULL);
+			break;
 		default:
 			ret = -EINVAL;
 			goto unlock;
@@ -133,10 +181,11 @@ static int __gup_test_ioctl(unsigned int
 	 * state: print a warning if any non-dma-pinned pages are found:
 	 */
 	verify_dma_pinned(cmd, pages, nr_pages);
+	dump_pages_test(gup, pages, nr_pages);
 
 	start_time = ktime_get();
 
-	put_back_pages(cmd, pages, nr_pages);
+	put_back_pages(cmd, pages, nr_pages, gup->flags);
 
 	end_time = ktime_get();
 	gup->put_delta_usec = ktime_us_delta(end_time, start_time);
@@ -161,6 +210,7 @@ static long gup_test_ioctl(struct file *
 	case PIN_LONGTERM_BENCHMARK:
 	case GUP_BASIC_TEST:
 	case PIN_BASIC_TEST:
+	case DUMP_USER_PAGES_TEST:
 		break;
 	default:
 		return -EINVAL;
--- a/mm/gup_test.h~selftests-vm-gup_test-introduce-the-dump_pages-sub-test
+++ a/mm/gup_test.h
@@ -9,6 +9,11 @@
 #define PIN_LONGTERM_BENCHMARK	_IOWR('g', 3, struct gup_test)
 #define GUP_BASIC_TEST		_IOWR('g', 4, struct gup_test)
 #define PIN_BASIC_TEST		_IOWR('g', 5, struct gup_test)
+#define DUMP_USER_PAGES_TEST	_IOWR('g', 6, struct gup_test)
+
+#define GUP_TEST_MAX_PAGES_TO_DUMP		8
+
+#define GUP_TEST_FLAG_DUMP_PAGES_USE_PIN	0x1
 
 struct gup_test {
 	__u64 get_delta_usec;
@@ -17,6 +22,11 @@ struct gup_test {
 	__u64 size;
 	__u32 nr_pages_per_call;
 	__u32 flags;
+	/*
+	 * Each non-zero entry is the number of the page (1-based: first page is
+	 * page 1, so that zero entries mean "do nothing") from the .addr base.
+	 */
+	__u32 which_pages[GUP_TEST_MAX_PAGES_TO_DUMP];
 };
 
 #endif	/* __GUP_TEST_H */
--- a/mm/Kconfig~selftests-vm-gup_test-introduce-the-dump_pages-sub-test
+++ a/mm/Kconfig
@@ -842,6 +842,12 @@ config GUP_TEST
 	  get_user_pages*() and pin_user_pages*(), as well as smoke tests of
 	  the non-_fast variants.
 
+	  There is also a sub-test that allows running dump_page() on any
+	  of up to eight pages (selected by command line args) within the
+	  range of user-space addresses. These pages are either pinned via
+	  pin_user_pages*(), or pinned via get_user_pages*(), as specified
+	  by other command line arguments.
+
 	  See tools/testing/selftests/vm/gup_test.c
 
 config GUP_GET_PTE_LOW_HIGH
--- a/tools/testing/selftests/vm/gup_test.c~selftests-vm-gup_test-introduce-the-dump_pages-sub-test
+++ a/tools/testing/selftests/vm/gup_test.c
@@ -27,21 +27,23 @@ static char *cmd_to_str(unsigned long cm
 		return "GUP_BASIC_TEST";
 	case PIN_BASIC_TEST:
 		return "PIN_BASIC_TEST";
+	case DUMP_USER_PAGES_TEST:
+		return "DUMP_USER_PAGES_TEST";
 	}
 	return "Unknown command";
 }
 
 int main(int argc, char **argv)
 {
-	struct gup_benchmark gup;
+	struct gup_test gup = { 0 };
 	unsigned long size = 128 * MB;
 	int i, fd, filed, opt, nr_pages = 1, thp = -1, repeats = 1, write = 0;
-	int cmd = GUP_FAST_BENCHMARK;
+	unsigned long cmd = GUP_FAST_BENCHMARK;
 	int flags = MAP_PRIVATE;
 	char *file = "/dev/zero";
 	char *p;
 
-	while ((opt = getopt(argc, argv, "m:r:n:f:abtTLUuwSH")) != -1) {
+	while ((opt = getopt(argc, argv, "m:r:n:F:f:abctTLUuwSH")) != -1) {
 		switch (opt) {
 		case 'a':
 			cmd = PIN_FAST_BENCHMARK;
@@ -52,6 +54,21 @@ int main(int argc, char **argv)
 		case 'L':
 			cmd = PIN_LONGTERM_BENCHMARK;
 			break;
+		case 'c':
+			cmd = DUMP_USER_PAGES_TEST;
+			/*
+			 * Dump page 0 (index 1). May be overridden later, by
+			 * user's non-option arguments.
+			 *
+			 * .which_pages is zero-based, so that zero can mean "do
+			 * nothing".
+			 */
+			gup.which_pages[0] = 1;
+			break;
+		case 'F':
+			/* strtol, so you can pass flags in hex form */
+			gup.flags = strtol(optarg, 0, 0);
+			break;
 		case 'm':
 			size = atoi(optarg) * MB;
 			break;
@@ -91,6 +108,30 @@ int main(int argc, char **argv)
 		}
 	}
 
+	if (optind < argc) {
+		int extra_arg_count = 0;
+		/*
+		 * For example:
+		 *
+		 *   ./gup_test -c 0 1 0x1001
+		 *
+		 * ...to dump pages 0, 1, and 4097
+		 */
+
+		while ((optind < argc) &&
+		       (extra_arg_count < GUP_TEST_MAX_PAGES_TO_DUMP)) {
+			/*
+			 * Do the 1-based indexing here, so that the user can
+			 * use normal 0-based indexing on the command line.
+			 */
+			long page_index = strtol(argv[optind], 0, 0) + 1;
+
+			gup.which_pages[extra_arg_count] = page_index;
+			extra_arg_count++;
+			optind++;
+		}
+	}
+
 	filed = open(file, O_RDWR|O_CREAT);
 	if (filed < 0) {
 		perror("open");
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 21/40] selftests/vm: run_vmtests.sh: update and clean up gup_test invocation
  2020-10-17 23:13 incoming Andrew Morton
                   ` (19 preceding siblings ...)
  2020-10-17 23:14 ` [patch 20/40] selftests/vm: gup_test: introduce the dump_pages() sub-test Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 22/40] selftests/vm: hmm-tests: remove the libhugetlbfs dependency Andrew Morton
                   ` (18 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: run_vmtests.sh: update and clean up gup_test invocation

Run benchmarks on the _fast variants of gup and pup, as originally
intended.

Run the new gup_test sub-test: dump pages.  In addition to exercising the
dump_page() call, it also demonstrates the various options you can use to
specify which pages to dump, and how.

Link: https://lkml.kernel.org/r/20200929212747.251804-8-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/vm/run_vmtests.sh |   24 +++++++++++++++-----
 1 file changed, 18 insertions(+), 6 deletions(-)

--- a/tools/testing/selftests/vm/run_vmtests.sh~selftests-vm-run_vmtestsh-update-and-clean-up-gup_test-invocation
+++ a/tools/testing/selftests/vm/run_vmtests.sh
@@ -124,9 +124,9 @@ else
 fi
 
 echo "--------------------------------------------"
-echo "running 'gup_test -U' (normal/slow gup)"
+echo "running 'gup_test -u' (fast gup benchmark)"
 echo "--------------------------------------------"
-./gup_test -U
+./gup_test -u
 if [ $? -ne 0 ]; then
 	echo "[FAIL]"
 	exitcode=1
@@ -134,10 +134,22 @@ else
 	echo "[PASS]"
 fi
 
-echo "------------------------------------------"
-echo "running gup_test -b (pin_user_pages)"
-echo "------------------------------------------"
-./gup_test -b
+echo "---------------------------------------------------"
+echo "running gup_test -a (pin_user_pages_fast benchmark)"
+echo "---------------------------------------------------"
+./gup_test -a
+if [ $? -ne 0 ]; then
+	echo "[FAIL]"
+	exitcode=1
+else
+	echo "[PASS]"
+fi
+
+echo "--------------------------------------------------------------"
+echo "running gup_test -ct -F 0x1 0 19 0x1000"
+echo "   Dumps pages 0, 19, and 4096, using pin_user_pages (-F 0x1)"
+echo "--------------------------------------------------------------"
+./gup_test -ct -F 0x1 0 19 0x1000
 if [ $? -ne 0 ]; then
 	echo "[FAIL]"
 	exitcode=1
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 22/40] selftests/vm: hmm-tests: remove the libhugetlbfs dependency
  2020-10-17 23:13 incoming Andrew Morton
                   ` (20 preceding siblings ...)
  2020-10-17 23:14 ` [patch 21/40] selftests/vm: run_vmtests.sh: update and clean up gup_test invocation Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 23/40] selftests/vm: 10x speedup for hmm-tests Andrew Morton
                   ` (17 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, corbet, jglisse, jhubbard, linux-mm, mm-commits, rcampbell,
	shuah, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: 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).

[jhubbard@nvidia.com: fix an improper dependency upon executable script permissions]
  Link: https://lkml.kernel.org/r/20201003002142.32671-2-jhubbard@nvidia.com
Link: https://lkml.kernel.org/r/20200929212747.251804-9-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>
---

 tools/testing/selftests/vm/.gitignore      |    1 
 tools/testing/selftests/vm/Makefile        |   24 +++++++++++++-
 tools/testing/selftests/vm/check_config.sh |   31 +++++++++++++++++++
 tools/testing/selftests/vm/hmm-tests.c     |   10 +++++-
 4 files changed, 63 insertions(+), 3 deletions(-)

--- /dev/null
+++ a/tools/testing/selftests/vm/check_config.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+#
+# Probe for libraries and create header files to record the results. Both C
+# header files and Makefile include fragments are created.
+
+OUTPUT_H_FILE=local_config.h
+OUTPUT_MKFILE=local_config.mk
+
+# libhugetlbfs
+tmpname=$(mktemp)
+tmpfile_c=${tmpname}.c
+tmpfile_o=${tmpname}.o
+
+echo "#include <sys/types.h>"        > $tmpfile_c
+echo "#include <hugetlbfs.h>"       >> $tmpfile_c
+echo "int func(void) { return 0; }" >> $tmpfile_c
+
+CC=${1:?"Usage: $0 <compiler> # example compiler: gcc"}
+$CC -c $tmpfile_c -o $tmpfile_o >/dev/null 2>&1
+
+if [ -f $tmpfile_o ]; then
+    echo "#define LOCAL_CONFIG_HAVE_LIBHUGETLBFS 1" > $OUTPUT_H_FILE
+    echo "HMM_EXTRA_LIBS = -lhugetlbfs"             > $OUTPUT_MKFILE
+else
+    echo "// No libhugetlbfs support found"      > $OUTPUT_H_FILE
+    echo "# No libhugetlbfs support found, so:"  > $OUTPUT_MKFILE
+    echo "HMM_EXTRA_LIBS = "                    >> $OUTPUT_MKFILE
+fi
+
+rm ${tmpname}.*
--- a/tools/testing/selftests/vm/.gitignore~selftests-vm-hmm-tests-remove-the-libhugetlbfs-dependency
+++ a/tools/testing/selftests/vm/.gitignore
@@ -20,3 +20,4 @@ va_128TBswitch
 map_fixed_noreplace
 write_to_hugetlbfs
 hmm-tests
+local_config.*
--- a/tools/testing/selftests/vm/hmm-tests.c~selftests-vm-hmm-tests-remove-the-libhugetlbfs-dependency
+++ a/tools/testing/selftests/vm/hmm-tests.c
@@ -21,12 +21,16 @@
 #include <strings.h>
 #include <time.h>
 #include <pthread.h>
-#include <hugetlbfs.h>
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/mman.h>
 #include <sys/ioctl.h>
 
+#include "./local_config.h"
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
+#include <hugetlbfs.h>
+#endif
+
 /*
  * This is a private UAPI to the kernel test module so it isn't exported
  * in the usual include/uapi/... directory.
@@ -662,6 +666,7 @@ TEST_F(hmm, anon_write_huge)
 	hmm_buffer_free(buffer);
 }
 
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
 /*
  * Write huge TLBFS page.
  */
@@ -720,6 +725,7 @@ TEST_F(hmm, anon_write_hugetlbfs)
 	buffer->ptr = NULL;
 	hmm_buffer_free(buffer);
 }
+#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
 
 /*
  * Read mmap'ed file memory.
@@ -1336,6 +1342,7 @@ TEST_F(hmm2, snapshot)
 	hmm_buffer_free(buffer);
 }
 
+#ifdef LOCAL_CONFIG_HAVE_LIBHUGETLBFS
 /*
  * Test the hmm_range_fault() HMM_PFN_PMD flag for large pages that
  * should be mapped by a large page table entry.
@@ -1411,6 +1418,7 @@ TEST_F(hmm, compound)
 	buffer->ptr = NULL;
 	hmm_buffer_free(buffer);
 }
+#endif /* LOCAL_CONFIG_HAVE_LIBHUGETLBFS */
 
 /*
  * Test two devices reading the same memory (double mapped).
--- a/tools/testing/selftests/vm/Makefile~selftests-vm-hmm-tests-remove-the-libhugetlbfs-dependency
+++ a/tools/testing/selftests/vm/Makefile
@@ -1,5 +1,8 @@
 # SPDX-License-Identifier: GPL-2.0
 # Makefile for vm selftests
+
+include local_config.mk
+
 uname_M := $(shell uname -m 2>/dev/null || echo not)
 MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/')
 
@@ -76,8 +79,6 @@ TEST_FILES := test_vmalloc.sh
 KSFT_KHDR_INSTALL := 1
 include ../lib.mk
 
-$(OUTPUT)/hmm-tests: LDLIBS += -lhugetlbfs
-
 ifeq ($(ARCH),x86_64)
 BINARIES_32 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_32))
 BINARIES_64 := $(patsubst %,$(OUTPUT)/%,$(BINARIES_64))
@@ -130,3 +131,22 @@ endif
 $(OUTPUT)/mlock-random-test: LDLIBS += -lcap
 
 $(OUTPUT)/gup_test: ../../../../mm/gup_test.h
+
+$(OUTPUT)/hmm-tests: local_config.h
+
+# HMM_EXTRA_LIBS may get set in local_config.mk, or it may be left empty.
+$(OUTPUT)/hmm-tests: LDLIBS += $(HMM_EXTRA_LIBS)
+
+local_config.mk local_config.h: check_config.sh
+	/bin/sh ./check_config.sh $(CC)
+
+EXTRA_CLEAN += local_config.mk local_config.h
+
+ifeq ($(HMM_EXTRA_LIBS),)
+all: warn_missing_hugelibs
+
+warn_missing_hugelibs:
+	@echo ; \
+	echo "Warning: missing libhugetlbfs support. Some HMM tests will be skipped." ; \
+	echo
+endif
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 23/40] selftests/vm: 10x speedup for hmm-tests
  2020-10-17 23:13 incoming Andrew Morton
                   ` (21 preceding siblings ...)
  2020-10-17 23:14 ` [patch 22/40] selftests/vm: hmm-tests: remove the libhugetlbfs dependency Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 24/40] mm/madvise: pass mm to do_madvise Andrew Morton
                   ` (16 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, jhubbard, linux-mm, mm-commits, rcampbell, shuah,
	sj38.park, torvalds

From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/vm: 10x speedup for hmm-tests

This patch reduces the running time for hmm-tests from about 10+ seconds,
to just under 1.0 second, for an approximately 10x speedup.  That brings
it in line with most of the other tests in selftests/vm, which mostly run
in < 1 sec.

This is done with a one-line change that simply reduces the number of
iterations of several tests, from 256, to 10.  Thanks to Ralph Campbell
for suggesting changing NTIMES as a way to get the speedup.

Link: https://lkml.kernel.org/r/20201003011721.44238-1-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Suggested-by: Ralph Campbell <rcampbell@nvidia.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/vm/hmm-tests.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/tools/testing/selftests/vm/hmm-tests.c~selftests-vm-10x-speedup-for-hmm-tests
+++ a/tools/testing/selftests/vm/hmm-tests.c
@@ -49,7 +49,7 @@ struct hmm_buffer {
 #define TWOMEG		(1 << 21)
 #define HMM_BUFFER_SIZE (1024 << 12)
 #define HMM_PATH_MAX    64
-#define NTIMES		256
+#define NTIMES		10
 
 #define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1)))
 
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 24/40] mm/madvise: pass mm to do_madvise
  2020-10-17 23:13 incoming Andrew Morton
                   ` (22 preceding siblings ...)
  2020-10-17 23:14 ` [patch 23/40] selftests/vm: 10x speedup for hmm-tests Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 25/40] pid: move pidfd_get_pid() to pid.c Andrew Morton
                   ` (15 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, alexander.h.duyck, axboe, bgeffon, christian.brauner,
	christian, dancol, fw, hannes, jannh, joaodias, joel, ktkhai,
	linux-man, linux-mm, mhocko, minchan, mm-commits, oleksandr,
	rientjes, shakeelb, sj38.park, sjpark, sonnyrao, sspatil, surenb,
	timmurray, torvalds, vbabka

From: Minchan Kim <minchan@kernel.org>
Subject: mm/madvise: pass mm to do_madvise

Patch series "introduce memory hinting API for external process", v9.

Now, we have MADV_PAGEOUT and MADV_COLD as madvise hinting API.  With
that, application could give hints to kernel what memory range are
preferred to be reclaimed.  However, in some platform(e.g., Android), the
information required to make the hinting decision is not known to the app.
Instead, it is known to a centralized userspace daemon(e.g.,
ActivityManagerService), and that daemon must be able to initiate reclaim
on its own without any app involvement.

To solve the concern, this patch introduces new syscall -
process_madvise(2).  Bascially, it's same with madvise(2) syscall but it
has some differences.

1. It needs pidfd of target process to provide the hint

2. It supports only MADV_{COLD|PAGEOUT|MERGEABLE|UNMEREABLE} at this
   moment.  Other hints in madvise will be opened when there are explicit
   requests from community to prevent unexpected bugs we couldn't support.

3. Only privileged processes can do something for other process's
   address space.

For more detail of the new API, please see "mm: introduce external memory
hinting API" description in this patchset.

This patch (of 3):

In upcoming patches, do_madvise will be called from external process
context so we shouldn't asssume "current" is always hinted process's
task_struct.

Furthermore, we must not access mm_struct via task->mm, but obtain it via
access_mm() once (in the following patch) and only use that pointer [1],
so pass it to do_madvise() as well.  Note the vma->vm_mm pointers are
safe, so we can use them further down the call stack.

And let's pass current->mm as arguments of do_madvise so it shouldn't
change existing behavior but prepare next patch to make review easy.

[vbabka@suse.cz: changelog tweak]
[minchan@kernel.org: use current->mm for io_uring]
  Link: http://lkml.kernel.org/r/20200423145215.72666-1-minchan@kernel.org
[akpm@linux-foundation.org: fix it for upstream changes]
[akpm@linux-foundation.org: whoops]
[rdunlap@infradead.org: add missing includes]
Link: https://lkml.kernel.org/r/20200901000633.1920247-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200622192900.22757-1-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200302193630.68771-2-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200622192900.22757-2-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-2-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jann Horn <jannh@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: John Dias <joaodias@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: Christian Brauner <christian@brauner.io>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/io_uring.c      |    2 +-
 include/linux/mm.h |    2 +-
 mm/madvise.c       |   32 ++++++++++++++++++--------------
 3 files changed, 20 insertions(+), 16 deletions(-)

--- a/fs/io_uring.c~mm-madvise-pass-mm-to-do_madvise
+++ a/fs/io_uring.c
@@ -3989,7 +3989,7 @@ static int io_madvise(struct io_kiocb *r
 	if (force_nonblock)
 		return -EAGAIN;
 
-	ret = do_madvise(ma->addr, ma->len, ma->advice);
+	ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
 	if (ret < 0)
 		req_set_fail_links(req);
 	io_req_complete(req, ret);
--- a/include/linux/mm.h~mm-madvise-pass-mm-to-do_madvise
+++ a/include/linux/mm.h
@@ -2579,7 +2579,7 @@ extern int __do_munmap(struct mm_struct
 		       struct list_head *uf, bool downgrade);
 extern int do_munmap(struct mm_struct *, unsigned long, size_t,
 		     struct list_head *uf);
-extern int do_madvise(unsigned long start, size_t len_in, int behavior);
+extern int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior);
 
 #ifdef CONFIG_MMU
 extern int __mm_populate(unsigned long addr, unsigned long len,
--- a/mm/madvise.c~mm-madvise-pass-mm-to-do_madvise
+++ a/mm/madvise.c
@@ -258,6 +258,7 @@ static long madvise_willneed(struct vm_a
 			     struct vm_area_struct **prev,
 			     unsigned long start, unsigned long end)
 {
+	struct mm_struct *mm = vma->vm_mm;
 	struct file *file = vma->vm_file;
 	loff_t offset;
 
@@ -294,10 +295,10 @@ static long madvise_willneed(struct vm_a
 	get_file(file);
 	offset = (loff_t)(start - vma->vm_start)
 			+ ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
-	mmap_read_unlock(current->mm);
+	mmap_read_unlock(mm);
 	vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED);
 	fput(file);
-	mmap_read_lock(current->mm);
+	mmap_read_lock(mm);
 	return 0;
 }
 
@@ -766,6 +767,8 @@ static long madvise_dontneed_free(struct
 				  unsigned long start, unsigned long end,
 				  int behavior)
 {
+	struct mm_struct *mm = vma->vm_mm;
+
 	*prev = vma;
 	if (!can_madv_lru_vma(vma))
 		return -EINVAL;
@@ -773,8 +776,8 @@ static long madvise_dontneed_free(struct
 	if (!userfaultfd_remove(vma, start, end)) {
 		*prev = NULL; /* mmap_lock has been dropped, prev is stale */
 
-		mmap_read_lock(current->mm);
-		vma = find_vma(current->mm, start);
+		mmap_read_lock(mm);
+		vma = find_vma(mm, start);
 		if (!vma)
 			return -ENOMEM;
 		if (start < vma->vm_start) {
@@ -828,6 +831,7 @@ static long madvise_remove(struct vm_are
 	loff_t offset;
 	int error;
 	struct file *f;
+	struct mm_struct *mm = vma->vm_mm;
 
 	*prev = NULL;	/* tell sys_madvise we drop mmap_lock */
 
@@ -855,13 +859,13 @@ static long madvise_remove(struct vm_are
 	get_file(f);
 	if (userfaultfd_remove(vma, start, end)) {
 		/* mmap_lock was not released by userfaultfd_remove() */
-		mmap_read_unlock(current->mm);
+		mmap_read_unlock(mm);
 	}
 	error = vfs_fallocate(f,
 				FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE,
 				offset, end - start);
 	fput(f);
-	mmap_read_lock(current->mm);
+	mmap_read_lock(mm);
 	return error;
 }
 
@@ -1045,7 +1049,7 @@ madvise_behavior_valid(int behavior)
  *  -EBADF  - map exists, but area maps something that isn't a file.
  *  -EAGAIN - a kernel resource was temporarily unavailable.
  */
-int do_madvise(unsigned long start, size_t len_in, int behavior)
+int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, int behavior)
 {
 	unsigned long end, tmp;
 	struct vm_area_struct *vma, *prev;
@@ -1083,10 +1087,10 @@ int do_madvise(unsigned long start, size
 
 	write = madvise_need_mmap_write(behavior);
 	if (write) {
-		if (mmap_write_lock_killable(current->mm))
+		if (mmap_write_lock_killable(mm))
 			return -EINTR;
 	} else {
-		mmap_read_lock(current->mm);
+		mmap_read_lock(mm);
 	}
 
 	/*
@@ -1094,7 +1098,7 @@ int do_madvise(unsigned long start, size
 	 * ranges, just ignore them, but return -ENOMEM at the end.
 	 * - different from the way of handling in mlock etc.
 	 */
-	vma = find_vma_prev(current->mm, start, &prev);
+	vma = find_vma_prev(mm, start, &prev);
 	if (vma && start > vma->vm_start)
 		prev = vma;
 
@@ -1131,19 +1135,19 @@ int do_madvise(unsigned long start, size
 		if (prev)
 			vma = prev->vm_next;
 		else	/* madvise_remove dropped mmap_lock */
-			vma = find_vma(current->mm, start);
+			vma = find_vma(mm, start);
 	}
 out:
 	blk_finish_plug(&plug);
 	if (write)
-		mmap_write_unlock(current->mm);
+		mmap_write_unlock(mm);
 	else
-		mmap_read_unlock(current->mm);
+		mmap_read_unlock(mm);
 
 	return error;
 }
 
 SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
 {
-	return do_madvise(start, len_in, behavior);
+	return do_madvise(current->mm, start, len_in, behavior);
 }
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 25/40] pid: move pidfd_get_pid() to pid.c
  2020-10-17 23:13 incoming Andrew Morton
                   ` (23 preceding siblings ...)
  2020-10-17 23:14 ` [patch 24/40] mm/madvise: pass mm to do_madvise Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:14 ` [patch 26/40] mm/madvise: introduce process_madvise() syscall: an external memory hinting API Andrew Morton
                   ` (14 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, alexander.h.duyck, axboe, bgeffon, christian.brauner,
	dancol, fw, hannes, jannh, joaodias, joel, ktkhai, linux-man,
	linux-mm, mhocko, minchan, mm-commits, oleksandr, rientjes,
	shakeelb, sj38.park, sjpark, sonnyrao, sspatil, surenb,
	timmurray, torvalds, vbabka

From: Minchan Kim <minchan@kernel.org>
Subject: pid: move pidfd_get_pid() to pid.c

process_madvise syscall needs pidfd_get_pid function to translate pidfd to
pid so this patch move the function to kernel/pid.c.

Link: http://lkml.kernel.org/r/20200302193630.68771-5-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200622192900.22757-3-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-3-minchan@kernel.org
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Suggested-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Reviewed-by: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jann Horn <jannh@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Daniel Colascione <dancol@google.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Dias <joaodias@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/pid.h |    1 +
 kernel/exit.c       |   19 -------------------
 kernel/pid.c        |   19 +++++++++++++++++++
 3 files changed, 20 insertions(+), 19 deletions(-)

--- a/include/linux/pid.h~pid-move-pidfd_get_pid-to-pidc
+++ a/include/linux/pid.h
@@ -77,6 +77,7 @@ extern const struct file_operations pidf
 struct file;
 
 extern struct pid *pidfd_pid(const struct file *file);
+struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags);
 
 static inline struct pid *get_pid(struct pid *pid)
 {
--- a/kernel/exit.c~pid-move-pidfd_get_pid-to-pidc
+++ a/kernel/exit.c
@@ -1474,25 +1474,6 @@ end:
 	return retval;
 }
 
-static struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags)
-{
-	struct fd f;
-	struct pid *pid;
-
-	f = fdget(fd);
-	if (!f.file)
-		return ERR_PTR(-EBADF);
-
-	pid = pidfd_pid(f.file);
-	if (!IS_ERR(pid)) {
-		get_pid(pid);
-		*flags = f.file->f_flags;
-	}
-
-	fdput(f);
-	return pid;
-}
-
 static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop,
 			  int options, struct rusage *ru)
 {
--- a/kernel/pid.c~pid-move-pidfd_get_pid-to-pidc
+++ a/kernel/pid.c
@@ -520,6 +520,25 @@ struct pid *find_ge_pid(int nr, struct p
 	return idr_get_next(&ns->idr, &nr);
 }
 
+struct pid *pidfd_get_pid(unsigned int fd, unsigned int *flags)
+{
+	struct fd f;
+	struct pid *pid;
+
+	f = fdget(fd);
+	if (!f.file)
+		return ERR_PTR(-EBADF);
+
+	pid = pidfd_pid(f.file);
+	if (!IS_ERR(pid)) {
+		get_pid(pid);
+		*flags = f.file->f_flags;
+	}
+
+	fdput(f);
+	return pid;
+}
+
 /**
  * pidfd_create() - Create a new pid file descriptor.
  *
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 26/40] mm/madvise: introduce process_madvise() syscall: an external memory hinting API
  2020-10-17 23:13 incoming Andrew Morton
                   ` (24 preceding siblings ...)
  2020-10-17 23:14 ` [patch 25/40] pid: move pidfd_get_pid() to pid.c Andrew Morton
@ 2020-10-17 23:14 ` Andrew Morton
  2020-10-17 23:15 ` [patch 27/40] mm: update the documentation for vfree Andrew Morton
                   ` (13 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:14 UTC (permalink / raw)
  To: akpm, alexander.h.duyck, axboe, bgeffon, christian.brauner,
	christian, dancol, fw, hannes, jannh, joaodias, joel, ktkhai,
	linux-man, linux-mm, mhocko, minchan, mm-commits, oleksandr,
	rientjes, sfr, shakeelb, sj38.park, sjpark, sonnyrao, sspatil,
	surenb, timmurray, torvalds, vbabka, yuehaibing

From: Minchan Kim <minchan@kernel.org>
Subject: mm/madvise: introduce process_madvise() syscall: an external memory hinting API

There is usecase that System Management Software(SMS) want to give a
memory hint like MADV_[COLD|PAGEEOUT] to other processes and in the
case of Android, it is the ActivityManagerService.

The information required to make the reclaim decision is not known to the
app.  Instead, it is known to the centralized userspace
daemon(ActivityManagerService), and that daemon must be able to initiate
reclaim on its own without any app involvement.

To solve the issue, this patch introduces a new syscall
process_madvise(2).  It uses pidfd of an external process to give the
hint.  It also supports vector address range because Android app has
thousands of vmas due to zygote so it's totally waste of CPU and power if
we should call the syscall one by one for each vma.(With testing 2000-vma
syscall vs 1-vector syscall, it showed 15% performance improvement.  I
think it would be bigger in real practice because the testing ran very
cache friendly environment).

Another potential use case for the vector range is to amortize the cost
ofTLB shootdowns for multiple ranges when using MADV_DONTNEED; this could
benefit users like TCP receive zerocopy and malloc implementations.  In
future, we could find more usecases for other advises so let's make it
happens as API since we introduce a new syscall at this moment.  With
that, existing madvise(2) user could replace it with process_madvise(2)
with their own pid if they want to have batch address ranges support
feature.

ince it could affect other process's address range, only privileged
process(PTRACE_MODE_ATTACH_FSCREDS) or something else(e.g., being the same
UID) gives it the right to ptrace the process could use it successfully. 
The flag argument is reserved for future use if we need to extend the API.

I think supporting all hints madvise has/will supported/support to
process_madvise is rather risky.  Because we are not sure all hints make
sense from external process and implementation for the hint may rely on
the caller being in the current context so it could be error-prone.  Thus,
I just limited hints as MADV_[COLD|PAGEOUT] in this patch.

If someone want to add other hints, we could hear the usecase and review
it for each hint.  It's safer for maintenance rather than introducing a
buggy syscall but hard to fix it later.

So finally, the API is as follows,

      ssize_t process_madvise(int pidfd, const struct iovec *iovec,
                unsigned long vlen, int advice, unsigned int flags);

    DESCRIPTION
      The process_madvise() system call is used to give advice or directions
      to the kernel about the address ranges from external process as well as
      local process. It provides the advice to address ranges of process
      described by iovec and vlen. The goal of such advice is to improve
      system or application performance.

      The pidfd selects the process referred to by the PID file descriptor
      specified in pidfd. (See pidofd_open(2) for further information)

      The pointer iovec points to an array of iovec structures, defined in
      <sys/uio.h> as:

        struct iovec {
            void *iov_base;         /* starting address */
            size_t iov_len;         /* number of bytes to be advised */
        };

      The iovec describes address ranges beginning at address(iov_base)
      and with size length of bytes(iov_len).

      The vlen represents the number of elements in iovec.

      The advice is indicated in the advice argument, which is one of the
      following at this moment if the target process specified by pidfd is
      external.

        MADV_COLD
        MADV_PAGEOUT

      Permission to provide a hint to external process is governed by a
      ptrace access mode PTRACE_MODE_ATTACH_FSCREDS check; see ptrace(2).

      The process_madvise supports every advice madvise(2) has if target
      process is in same thread group with calling process so user could
      use process_madvise(2) to extend existing madvise(2) to support
      vector address ranges.

    RETURN VALUE
      On success, process_madvise() returns the number of bytes advised.
      This return value may be less than the total number of requested
      bytes, if an error occurred. The caller should check return value
      to determine whether a partial advice occurred.

FAQ:

Q.1 - Why does any external entity have better knowledge?

Quote from Sandeep

"For Android, every application (including the special SystemServer)
are forked from Zygote.  The reason of course is to share as many
libraries and classes between the two as possible to benefit from the
preloading during boot.

After applications start, (almost) all of the APIs end up calling into
this SystemServer process over IPC (binder) and back to the
application.

In a fully running system, the SystemServer monitors every single
process periodically to calculate their PSS / RSS and also decides
which process is "important" to the user for interactivity.

So, because of how these processes start _and_ the fact that the
SystemServer is looping to monitor each process, it does tend to *know*
which address range of the application is not used / useful.

Besides, we can never rely on applications to clean things up
themselves.  We've had the "hey app1, the system is low on memory,
please trim your memory usage down" notifications for a long time[1].
They rely on applications honoring the broadcasts and very few do.

So, if we want to avoid the inevitable killing of the application and
restarting it, some way to be able to tell the OS about unimportant
memory in these applications will be useful.

- ssp

Q.2 - How to guarantee the race(i.e., object validation) between when
giving a hint from an external process and get the hint from the target
process?

process_madvise operates on the target process's address space as it
exists at the instant that process_madvise is called.  If the space
target process can run between the time the process_madvise process
inspects the target process address space and the time that
process_madvise is actually called, process_madvise may operate on
memory regions that the calling process does not expect.  It's the
responsibility of the process calling process_madvise to close this
race condition.  For example, the calling process can suspend the
target process with ptrace, SIGSTOP, or the freezer cgroup so that it
doesn't have an opportunity to change its own address space before
process_madvise is called.  Another option is to operate on memory
regions that the caller knows a priori will be unchanged in the target
process.  Yet another option is to accept the race for certain
process_madvise calls after reasoning that mistargeting will do no
harm.  The suggested API itself does not provide synchronization.  It
also apply other APIs like move_pages, process_vm_write.

The race isn't really a problem though.  Why is it so wrong to require
that callers do their own synchronization in some manner?  Nobody
objects to write(2) merely because it's possible for two processes to
open the same file and clobber each other's writes --- instead, we tell
people to use flock or something.  Think about mmap.  It never
guarantees newly allocated address space is still valid when the user
tries to access it because other threads could unmap the memory right
before.  That's where we need synchronization by using other API or
design from userside.  It shouldn't be part of API itself.  If someone
needs more fine-grained synchronization rather than process level,
there were two ideas suggested - cookie[2] and anon-fd[3].  Both are
applicable via using last reserved argument of the API but I don't
think it's necessary right now since we have already ways to prevent
the race so don't want to add additional complexity with more
fine-grained optimization model.

To make the API extend, it reserved an unsigned long as last argument
so we could support it in future if someone really needs it.

Q.3 - Why doesn't ptrace work?

Injecting an madvise in the target process using ptrace would not work
for us because such injected madvise would have to be executed by the
target process, which means that process would have to be runnable and
that creates the risk of the abovementioned race and hinting a wrong
VMA.  Furthermore, we want to act the hint in caller's context, not the
callee's, because the callee is usually limited in cpuset/cgroups or
even freezed state so they can't act by themselves quick enough, which
causes more thrashing/kill.  It doesn't work if the target process are
ptraced(e.g., strace, debugger, minidump) because a process can have at
most one ptracer.

[1] https://developer.android.com/topic/performance/memory"

[2] process_getinfo for getting the cookie which is updated whenever
    vma of process address layout are changed - Daniel Colascione -
    https://lore.kernel.org/lkml/20190520035254.57579-1-minchan@kernel.org/T/#m7694416fd179b2066a2c62b5b139b14e3894e224

[3] anonymous fd which is used for the object(i.e., address range)
    validation - Michal Hocko -
    https://lore.kernel.org/lkml/20200120112722.GY18451@dhcp22.suse.cz/

[minchan@kernel.org: fix process_madvise build break for arm64]
  Link: http://lkml.kernel.org/r/20200303145756.GA219683@google.com
[minchan@kernel.org: fix build error for mips of process_madvise]
  Link: http://lkml.kernel.org/r/20200508052517.GA197378@google.com
[akpm@linux-foundation.org: fix patch ordering issue]
[akpm@linux-foundation.org: fix arm64 whoops]
[minchan@kernel.org: make process_madvise() vlen arg have type size_t, per Florian]
[akpm@linux-foundation.org: fix i386 build]
[sfr@canb.auug.org.au: fix syscall numbering]
  Link: https://lkml.kernel.org/r/20200905142639.49fc3f1a@canb.auug.org.au
[sfr@canb.auug.org.au: madvise.c needs compat.h]
  Link: https://lkml.kernel.org/r/20200908204547.285646b4@canb.auug.org.au
[minchan@kernel.org: fix mips build]
  Link: https://lkml.kernel.org/r/20200909173655.GC2435453@google.com
[yuehaibing@huawei.com: remove duplicate header which is included twice]
  Link: https://lkml.kernel.org/r/20200915121550.30584-1-yuehaibing@huawei.com
[minchan@kernel.org: do not use helper functions for process_madvise]
  Link: https://lkml.kernel.org/r/20200921175539.GB387368@google.com
[akpm@linux-foundation.org: pidfd_get_pid() gained an argument]
[sfr@canb.auug.org.au: fix up for "iov_iter: transparently handle compat iovecs in import_iovec"]
  Link: https://lkml.kernel.org/r/20200928212542.468e1fef@canb.auug.org.au
Link: http://lkml.kernel.org/r/20200302193630.68771-3-minchan@kernel.org
Link: http://lkml.kernel.org/r/20200508183320.GA125527@google.com
Link: http://lkml.kernel.org/r/20200622192900.22757-4-minchan@kernel.org
Link: https://lkml.kernel.org/r/20200901000633.1920247-4-minchan@kernel.org
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Alexander Duyck <alexander.h.duyck@linux.intel.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Christian Brauner <christian@brauner.io>
Cc: Daniel Colascione <dancol@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Dias <joaodias@google.com>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: SeongJae Park <sj38.park@gmail.com>
Cc: SeongJae Park <sjpark@amazon.de>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Sonny Rao <sonnyrao@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Cc: <linux-man@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/alpha/kernel/syscalls/syscall.tbl      |    1 
 arch/arm/tools/syscall.tbl                  |    1 
 arch/arm64/include/asm/unistd.h             |    2 
 arch/arm64/include/asm/unistd32.h           |    2 
 arch/ia64/kernel/syscalls/syscall.tbl       |    1 
 arch/m68k/kernel/syscalls/syscall.tbl       |    1 
 arch/microblaze/kernel/syscalls/syscall.tbl |    1 
 arch/mips/kernel/syscalls/syscall_n32.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_n64.tbl   |    1 
 arch/mips/kernel/syscalls/syscall_o32.tbl   |    1 
 arch/parisc/kernel/syscalls/syscall.tbl     |    1 
 arch/powerpc/kernel/syscalls/syscall.tbl    |    1 
 arch/s390/kernel/syscalls/syscall.tbl       |    1 
 arch/sh/kernel/syscalls/syscall.tbl         |    1 
 arch/sparc/kernel/syscalls/syscall.tbl      |    1 
 arch/x86/entry/syscalls/syscall_32.tbl      |    1 
 arch/x86/entry/syscalls/syscall_64.tbl      |    1 
 arch/xtensa/kernel/syscalls/syscall.tbl     |    1 
 include/linux/syscalls.h                    |    2 
 include/uapi/asm-generic/unistd.h           |    4 
 kernel/sys_ni.c                             |    1 
 mm/madvise.c                                |   93 +++++++++++++++++-
 22 files changed, 117 insertions(+), 3 deletions(-)

--- a/arch/alpha/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/alpha/kernel/syscalls/syscall.tbl
@@ -479,3 +479,4 @@
 547	common	openat2				sys_openat2
 548	common	pidfd_getfd			sys_pidfd_getfd
 549	common	faccessat2			sys_faccessat2
+550	common	process_madvise			sys_process_madvise
--- a/arch/arm64/include/asm/unistd32.h~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/arm64/include/asm/unistd32.h
@@ -887,6 +887,8 @@ __SYSCALL(__NR_openat2, sys_openat2)
 __SYSCALL(__NR_pidfd_getfd, sys_pidfd_getfd)
 #define __NR_faccessat2 439
 __SYSCALL(__NR_faccessat2, sys_faccessat2)
+#define __NR_process_madvise 440
+__SYSCALL(__NR_process_madvise, sys_process_madvise)
 
 /*
  * Please add new compat syscalls above this comment and update
--- a/arch/arm64/include/asm/unistd.h~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/arm64/include/asm/unistd.h
@@ -38,7 +38,7 @@
 #define __ARM_NR_compat_set_tls		(__ARM_NR_COMPAT_BASE + 5)
 #define __ARM_NR_COMPAT_END		(__ARM_NR_COMPAT_BASE + 0x800)
 
-#define __NR_compat_syscalls		440
+#define __NR_compat_syscalls		441
 #endif
 
 #define __ARCH_WANT_SYS_CLONE
--- a/arch/arm/tools/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/arm/tools/syscall.tbl
@@ -453,3 +453,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/ia64/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/ia64/kernel/syscalls/syscall.tbl
@@ -360,3 +360,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/m68k/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/m68k/kernel/syscalls/syscall.tbl
@@ -439,3 +439,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/microblaze/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/microblaze/kernel/syscalls/syscall.tbl
@@ -445,3 +445,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/mips/kernel/syscalls/syscall_n32.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/mips/kernel/syscalls/syscall_n32.tbl
@@ -378,3 +378,4 @@
 437	n32	openat2				sys_openat2
 438	n32	pidfd_getfd			sys_pidfd_getfd
 439	n32	faccessat2			sys_faccessat2
+440	n32	process_madvise			sys_process_madvise
--- a/arch/mips/kernel/syscalls/syscall_n64.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/mips/kernel/syscalls/syscall_n64.tbl
@@ -354,3 +354,4 @@
 437	n64	openat2				sys_openat2
 438	n64	pidfd_getfd			sys_pidfd_getfd
 439	n64	faccessat2			sys_faccessat2
+440	n64	process_madvise			sys_process_madvise
--- a/arch/mips/kernel/syscalls/syscall_o32.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/mips/kernel/syscalls/syscall_o32.tbl
@@ -427,3 +427,4 @@
 437	o32	openat2				sys_openat2
 438	o32	pidfd_getfd			sys_pidfd_getfd
 439	o32	faccessat2			sys_faccessat2
+440	o32	process_madvise			sys_process_madvise
--- a/arch/parisc/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/parisc/kernel/syscalls/syscall.tbl
@@ -437,3 +437,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/powerpc/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/powerpc/kernel/syscalls/syscall.tbl
@@ -529,3 +529,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/s390/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/s390/kernel/syscalls/syscall.tbl
@@ -442,3 +442,4 @@
 437  common	openat2			sys_openat2			sys_openat2
 438  common	pidfd_getfd		sys_pidfd_getfd			sys_pidfd_getfd
 439  common	faccessat2		sys_faccessat2			sys_faccessat2
+440  common	process_madvise		sys_process_madvise		sys_process_madvise
--- a/arch/sh/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/sh/kernel/syscalls/syscall.tbl
@@ -442,3 +442,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/sparc/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/sparc/kernel/syscalls/syscall.tbl
@@ -485,3 +485,4 @@
 437	common	openat2			sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/arch/x86/entry/syscalls/syscall_32.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/x86/entry/syscalls/syscall_32.tbl
@@ -444,3 +444,4 @@
 437	i386	openat2			sys_openat2
 438	i386	pidfd_getfd		sys_pidfd_getfd
 439	i386	faccessat2		sys_faccessat2
+440	i386	process_madvise		sys_process_madvise
--- a/arch/x86/entry/syscalls/syscall_64.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/x86/entry/syscalls/syscall_64.tbl
@@ -361,6 +361,7 @@
 437	common	openat2			sys_openat2
 438	common	pidfd_getfd		sys_pidfd_getfd
 439	common	faccessat2		sys_faccessat2
+440	common	process_madvise		sys_process_madvise
 
 #
 # x32-specific system call numbers start at 512 to avoid cache impact
--- a/arch/xtensa/kernel/syscalls/syscall.tbl~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/arch/xtensa/kernel/syscalls/syscall.tbl
@@ -410,3 +410,4 @@
 437	common	openat2				sys_openat2
 438	common	pidfd_getfd			sys_pidfd_getfd
 439	common	faccessat2			sys_faccessat2
+440	common	process_madvise			sys_process_madvise
--- a/include/linux/syscalls.h~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/include/linux/syscalls.h
@@ -879,6 +879,8 @@ asmlinkage long sys_munlockall(void);
 asmlinkage long sys_mincore(unsigned long start, size_t len,
 				unsigned char __user * vec);
 asmlinkage long sys_madvise(unsigned long start, size_t len, int behavior);
+asmlinkage long sys_process_madvise(int pidfd, const struct iovec __user *vec,
+			size_t vlen, int behavior, unsigned int flags);
 asmlinkage long sys_remap_file_pages(unsigned long start, unsigned long size,
 			unsigned long prot, unsigned long pgoff,
 			unsigned long flags);
--- a/include/uapi/asm-generic/unistd.h~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/include/uapi/asm-generic/unistd.h
@@ -857,9 +857,11 @@ __SYSCALL(__NR_openat2, sys_openat2)
 __SYSCALL(__NR_pidfd_getfd, sys_pidfd_getfd)
 #define __NR_faccessat2 439
 __SYSCALL(__NR_faccessat2, sys_faccessat2)
+#define __NR_process_madvise 440
+__SYSCALL(__NR_process_madvise, sys_process_madvise)
 
 #undef __NR_syscalls
-#define __NR_syscalls 440
+#define __NR_syscalls 441
 
 /*
  * 32 bit systems traditionally used different
--- a/kernel/sys_ni.c~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/kernel/sys_ni.c
@@ -280,6 +280,7 @@ COND_SYSCALL(mlockall);
 COND_SYSCALL(munlockall);
 COND_SYSCALL(mincore);
 COND_SYSCALL(madvise);
+COND_SYSCALL(process_madvise);
 COND_SYSCALL(remap_file_pages);
 COND_SYSCALL(mbind);
 COND_SYSCALL_COMPAT(mbind);
--- a/mm/madvise.c~mm-madvise-introduce-process_madvise-syscall-an-external-memory-hinting-api
+++ a/mm/madvise.c
@@ -17,6 +17,8 @@
 #include <linux/falloc.h>
 #include <linux/fadvise.h>
 #include <linux/sched.h>
+#include <linux/sched/mm.h>
+#include <linux/uio.h>
 #include <linux/ksm.h>
 #include <linux/fs.h>
 #include <linux/file.h>
@@ -27,7 +29,6 @@
 #include <linux/swapops.h>
 #include <linux/shmem_fs.h>
 #include <linux/mmu_notifier.h>
-#include <linux/sched/mm.h>
 
 #include <asm/tlb.h>
 
@@ -988,6 +989,18 @@ madvise_behavior_valid(int behavior)
 	}
 }
 
+static bool
+process_madvise_behavior_valid(int behavior)
+{
+	switch (behavior) {
+	case MADV_COLD:
+	case MADV_PAGEOUT:
+		return true;
+	default:
+		return false;
+	}
+}
+
 /*
  * The madvise(2) system call.
  *
@@ -1035,6 +1048,11 @@ madvise_behavior_valid(int behavior)
  *  MADV_DONTDUMP - the application wants to prevent pages in the given range
  *		from being included in its core dump.
  *  MADV_DODUMP - cancel MADV_DONTDUMP: no longer exclude from core dump.
+ *  MADV_COLD - the application is not expected to use this memory soon,
+ *		deactivate pages in this range so that they can be reclaimed
+ *		easily if memory pressure hanppens.
+ *  MADV_PAGEOUT - the application is not expected to use this memory soon,
+ *		page out the pages in this range immediately.
  *
  * return values:
  *  zero    - success
@@ -1151,3 +1169,76 @@ SYSCALL_DEFINE3(madvise, unsigned long,
 {
 	return do_madvise(current->mm, start, len_in, behavior);
 }
+
+SYSCALL_DEFINE5(process_madvise, int, pidfd, const struct iovec __user *, vec,
+		size_t, vlen, int, behavior, unsigned int, flags)
+{
+	ssize_t ret;
+	struct iovec iovstack[UIO_FASTIOV], iovec;
+	struct iovec *iov = iovstack;
+	struct iov_iter iter;
+	struct pid *pid;
+	struct task_struct *task;
+	struct mm_struct *mm;
+	size_t total_len;
+	unsigned int f_flags;
+
+	if (flags != 0) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	ret = import_iovec(READ, vec, vlen, ARRAY_SIZE(iovstack), &iov, &iter);
+	if (ret < 0)
+		goto out;
+
+	pid = pidfd_get_pid(pidfd, &f_flags);
+	if (IS_ERR(pid)) {
+		ret = PTR_ERR(pid);
+		goto free_iov;
+	}
+
+	task = get_pid_task(pid, PIDTYPE_PID);
+	if (!task) {
+		ret = -ESRCH;
+		goto put_pid;
+	}
+
+	if (task->mm != current->mm &&
+			!process_madvise_behavior_valid(behavior)) {
+		ret = -EINVAL;
+		goto release_task;
+	}
+
+	mm = mm_access(task, PTRACE_MODE_ATTACH_FSCREDS);
+	if (IS_ERR_OR_NULL(mm)) {
+		ret = IS_ERR(mm) ? PTR_ERR(mm) : -ESRCH;
+		goto release_task;
+	}
+
+	total_len = iov_iter_count(&iter);
+
+	while (iov_iter_count(&iter)) {
+		iovec = iov_iter_iovec(&iter);
+		ret = do_madvise(mm, (unsigned long)iovec.iov_base,
+					iovec.iov_len, behavior);
+		if (ret < 0)
+			break;
+		iov_iter_advance(&iter, iovec.iov_len);
+	}
+
+	if (ret == 0)
+		ret = total_len - iov_iter_count(&iter);
+
+	mmput(mm);
+	return ret;
+
+release_task:
+	put_task_struct(task);
+put_pid:
+	put_pid(pid);
+free_iov:
+	kfree(iov);
+out:
+	return ret;
+}
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 27/40] mm: update the documentation for vfree
  2020-10-17 23:13 incoming Andrew Morton
                   ` (25 preceding siblings ...)
  2020-10-17 23:14 ` [patch 26/40] mm/madvise: introduce process_madvise() syscall: an external memory hinting API Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 28/40] mm: add a VM_MAP_PUT_PAGES flag for vmap Andrew Morton
                   ` (12 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: mm: update the documentation for vfree

Patch series "remove alloc_vm_area", v4.

This series removes alloc_vm_area, which was left over from the big
vmalloc interface rework.  It is a rather arkane interface, basicaly the
equivalent of get_vm_area + actually faulting in all PTEs in the allocated
area.  It was originally addeds for Xen (which isn't modular to start
with), and then grew users in zsmalloc and i915 which seems to mostly
qualify as abuses of the interface, especially for i915 as a random driver
should not set up PTE bits directly.


This patch (of 11):

 * Document that you can call vfree() on an address returned from vmap()
 * Remove the note about the minimum size -- the minimum size of a vmalloc
   allocation is one page
 * Add a Context: section
 * Fix capitalisation
 * Reword the prohibition on calling from NMI context to avoid a double
   negative

Link: https://lkml.kernel.org/r/20201002122204.1534411-1-hch@lst.de
Link: https://lkml.kernel.org/r/20201002122204.1534411-2-hch@lst.de
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |   21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

--- a/mm/vmalloc.c~mm-update-the-documentation-for-vfree
+++ a/mm/vmalloc.c
@@ -2321,20 +2321,21 @@ static void __vfree(const void *addr)
 }
 
 /**
- * vfree - release memory allocated by vmalloc()
- * @addr:  memory base address
+ * vfree - Release memory allocated by vmalloc()
+ * @addr:  Memory base address
  *
- * Free the virtually continuous memory area starting at @addr, as
- * obtained from vmalloc(), vmalloc_32() or __vmalloc(). If @addr is
- * NULL, no operation is performed.
+ * Free the virtually continuous memory area starting at @addr, as obtained
+ * from one of the vmalloc() family of APIs.  This will usually also free the
+ * physical memory underlying the virtual allocation, but that memory is
+ * reference counted, so it will not be freed until the last user goes away.
  *
- * Must not be called in NMI context (strictly speaking, only if we don't
- * have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
- * conventions for vfree() arch-depenedent would be a really bad idea)
+ * If @addr is NULL, no operation is performed.
  *
+ * Context:
  * May sleep if called *not* from interrupt context.
- *
- * NOTE: assumes that the object at @addr has a size >= sizeof(llist_node)
+ * Must not be called in NMI context (strictly speaking, it could be
+ * if we have CONFIG_ARCH_HAVE_NMI_SAFE_CMPXCHG, but making the calling
+ * conventions for vfree() arch-depenedent would be a really bad idea).
  */
 void vfree(const void *addr)
 {
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 28/40] mm: add a VM_MAP_PUT_PAGES flag for vmap
  2020-10-17 23:13 incoming Andrew Morton
                   ` (26 preceding siblings ...)
  2020-10-17 23:15 ` [patch 27/40] mm: update the documentation for vfree Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 29/40] mm: add a vmap_pfn function Andrew Morton
                   ` (11 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: mm: add a VM_MAP_PUT_PAGES flag for vmap

Add a flag so that vmap takes ownership of the passed in page array.  When
vfree is called on such an allocation it will put one reference on each
page, and free the page array itself.

Link: https://lkml.kernel.org/r/20201002122204.1534411-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/vmalloc.h |    1 +
 mm/vmalloc.c            |    9 +++++++--
 2 files changed, 8 insertions(+), 2 deletions(-)

--- a/include/linux/vmalloc.h~mm-add-a-vm_map_put_pages-flag-for-vmap
+++ a/include/linux/vmalloc.h
@@ -24,6 +24,7 @@ struct notifier_block;		/* in notifier.h
 #define VM_UNINITIALIZED	0x00000020	/* vm_struct is not fully initialized */
 #define VM_NO_GUARD		0x00000040      /* don't add guard page */
 #define VM_KASAN		0x00000080      /* has allocated kasan shadow memory */
+#define VM_MAP_PUT_PAGES	0x00000100	/* put pages and free array in vfree */
 
 /*
  * VM_KASAN is used slighly differently depending on CONFIG_KASAN_VMALLOC.
--- a/mm/vmalloc.c~mm-add-a-vm_map_put_pages-flag-for-vmap
+++ a/mm/vmalloc.c
@@ -2377,8 +2377,11 @@ EXPORT_SYMBOL(vunmap);
  * @flags: vm_area->flags
  * @prot: page protection for the mapping
  *
- * Maps @count pages from @pages into contiguous kernel virtual
- * space.
+ * Maps @count pages from @pages into contiguous kernel virtual space.
+ * If @flags contains %VM_MAP_PUT_PAGES the ownership of the pages array itself
+ * (which must be kmalloc or vmalloc memory) and one reference per pages in it
+ * are transferred from the caller to vmap(), and will be freed / dropped when
+ * vfree() is called on the return value.
  *
  * Return: the address of the area or %NULL on failure
  */
@@ -2404,6 +2407,8 @@ void *vmap(struct page **pages, unsigned
 		return NULL;
 	}
 
+	if (flags & VM_MAP_PUT_PAGES)
+		area->pages = pages;
 	return area->addr;
 }
 EXPORT_SYMBOL(vmap);
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 29/40] mm: add a vmap_pfn function
  2020-10-17 23:13 incoming Andrew Morton
                   ` (27 preceding siblings ...)
  2020-10-17 23:15 ` [patch 28/40] mm: add a VM_MAP_PUT_PAGES flag for vmap Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 30/40] mm: allow a NULL fn callback in apply_to_page_range Andrew Morton
                   ` (10 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: mm: add a vmap_pfn function

Add a proper helper to remap PFNs into kernel virtual space so that
drivers don't have to abuse alloc_vm_area and open coded PTE manipulation
for it.

Link: https://lkml.kernel.org/r/20201002122204.1534411-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/vmalloc.h |    1 
 mm/Kconfig              |    3 ++
 mm/vmalloc.c            |   45 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 49 insertions(+)

--- a/include/linux/vmalloc.h~mm-add-a-vmap_pfn-function
+++ a/include/linux/vmalloc.h
@@ -122,6 +122,7 @@ extern void vfree_atomic(const void *add
 
 extern void *vmap(struct page **pages, unsigned int count,
 			unsigned long flags, pgprot_t prot);
+void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot);
 extern void vunmap(const void *addr);
 
 extern int remap_vmalloc_range_partial(struct vm_area_struct *vma,
--- a/mm/Kconfig~mm-add-a-vmap_pfn-function
+++ a/mm/Kconfig
@@ -816,6 +816,9 @@ config DEVICE_PRIVATE
 	  memory; i.e., memory that is only accessible from the device (or
 	  group of devices). You likely also want to select HMM_MIRROR.
 
+config VMAP_PFN
+	bool
+
 config FRAME_VECTOR
 	bool
 
--- a/mm/vmalloc.c~mm-add-a-vmap_pfn-function
+++ a/mm/vmalloc.c
@@ -2413,6 +2413,51 @@ void *vmap(struct page **pages, unsigned
 }
 EXPORT_SYMBOL(vmap);
 
+#ifdef CONFIG_VMAP_PFN
+struct vmap_pfn_data {
+	unsigned long	*pfns;
+	pgprot_t	prot;
+	unsigned int	idx;
+};
+
+static int vmap_pfn_apply(pte_t *pte, unsigned long addr, void *private)
+{
+	struct vmap_pfn_data *data = private;
+
+	if (WARN_ON_ONCE(pfn_valid(data->pfns[data->idx])))
+		return -EINVAL;
+	*pte = pte_mkspecial(pfn_pte(data->pfns[data->idx++], data->prot));
+	return 0;
+}
+
+/**
+ * vmap_pfn - map an array of PFNs into virtually contiguous space
+ * @pfns: array of PFNs
+ * @count: number of pages to map
+ * @prot: page protection for the mapping
+ *
+ * Maps @count PFNs from @pfns into contiguous kernel virtual space and returns
+ * the start address of the mapping.
+ */
+void *vmap_pfn(unsigned long *pfns, unsigned int count, pgprot_t prot)
+{
+	struct vmap_pfn_data data = { .pfns = pfns, .prot = pgprot_nx(prot) };
+	struct vm_struct *area;
+
+	area = get_vm_area_caller(count * PAGE_SIZE, VM_IOREMAP,
+			__builtin_return_address(0));
+	if (!area)
+		return NULL;
+	if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
+			count * PAGE_SIZE, vmap_pfn_apply, &data)) {
+		free_vm_area(area);
+		return NULL;
+	}
+	return area->addr;
+}
+EXPORT_SYMBOL_GPL(vmap_pfn);
+#endif /* CONFIG_VMAP_PFN */
+
 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 				 pgprot_t prot, int node)
 {
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 30/40] mm: allow a NULL fn callback in apply_to_page_range
  2020-10-17 23:13 incoming Andrew Morton
                   ` (28 preceding siblings ...)
  2020-10-17 23:15 ` [patch 29/40] mm: add a vmap_pfn function Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 31/40] zsmalloc: switch from alloc_vm_area to get_vm_area Andrew Morton
                   ` (9 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, mm-commits, ngupta,
	peterz, rodrigo.vivi, sstabellini, torvalds, tvrtko.ursulin,
	urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: mm: allow a NULL fn callback in apply_to_page_range

Besides calling the callback on each page, apply_to_page_range also has
the effect of pre-faulting all PTEs for the range.  To support callers
that only need the pre-faulting, make the callback optional.

Based on a patch from Minchan Kim <minchan@kernel.org>.

Link: https://lkml.kernel.org/r/20201002122204.1534411-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/memory.c |   16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

--- a/mm/memory.c~mm-allow-a-null-fn-callback-in-apply_to_page_range
+++ a/mm/memory.c
@@ -2391,13 +2391,15 @@ static int apply_to_pte_range(struct mm_
 
 	arch_enter_lazy_mmu_mode();
 
-	do {
-		if (create || !pte_none(*pte)) {
-			err = fn(pte++, addr, data);
-			if (err)
-				break;
-		}
-	} while (addr += PAGE_SIZE, addr != end);
+	if (fn) {
+		do {
+			if (create || !pte_none(*pte)) {
+				err = fn(pte++, addr, data);
+				if (err)
+					break;
+			}
+		} while (addr += PAGE_SIZE, addr != end);
+	}
 	*mask |= PGTBL_PTE_MODIFIED;
 
 	arch_leave_lazy_mmu_mode();
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 31/40] zsmalloc: switch from alloc_vm_area to get_vm_area
  2020-10-17 23:13 incoming Andrew Morton
                   ` (29 preceding siblings ...)
  2020-10-17 23:15 ` [patch 30/40] mm: allow a NULL fn callback in apply_to_page_range Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 32/40] drm/i915: use vmap in shmem_pin_map Andrew Morton
                   ` (8 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: zsmalloc: switch from alloc_vm_area to get_vm_area

Just manually pre-fault the PTEs using apply_to_page_range.

Link: https://lkml.kernel.org/r/20201002122204.1534411-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Co-developed-by: Minchan Kim <minchan@kernel.org>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/zsmalloc.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/mm/zsmalloc.c~zsmalloc-switch-from-alloc_vm_area-to-get_vm_area
+++ a/mm/zsmalloc.c
@@ -1122,10 +1122,16 @@ static inline int __zs_cpu_up(struct map
 	 */
 	if (area->vm)
 		return 0;
-	area->vm = alloc_vm_area(PAGE_SIZE * 2, NULL);
+	area->vm = get_vm_area(PAGE_SIZE * 2, 0);
 	if (!area->vm)
 		return -ENOMEM;
-	return 0;
+
+	/*
+	 * Populate ptes in advance to avoid pte allocation with GFP_KERNEL
+	 * in non-preemtible context of zs_map_object.
+	 */
+	return apply_to_page_range(&init_mm, (unsigned long)area->vm->addr,
+			PAGE_SIZE * 2, NULL, NULL);
 }
 
 static inline void __zs_cpu_down(struct mapping_area *area)
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 32/40] drm/i915: use vmap in shmem_pin_map
  2020-10-17 23:13 incoming Andrew Morton
                   ` (30 preceding siblings ...)
  2020-10-17 23:15 ` [patch 31/40] zsmalloc: switch from alloc_vm_area to get_vm_area Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 33/40] drm/i915: stop using kmap in i915_gem_object_map Andrew Morton
                   ` (7 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: drm/i915: use vmap in shmem_pin_map

shmem_pin_map somewhat awkwardly reimplements vmap using alloc_vm_area and
manual pte setup.  The only practical difference is that alloc_vm_area
prefeaults the vmalloc area PTEs, which doesn't seem to be required here
(and could be added to vmap using a flag if actually required).  Switch to
use vmap, and use vfree to free both the vmalloc mapping and the page
array, as well as dropping the references to each page.

Link: https://lkml.kernel.org/r/20201002122204.1534411-7-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/gpu/drm/i915/gt/shmem_utils.c |   78 +++++-------------------
 1 file changed, 19 insertions(+), 59 deletions(-)

--- a/drivers/gpu/drm/i915/gt/shmem_utils.c~drm-i915-use-vmap-in-shmem_pin_map
+++ a/drivers/gpu/drm/i915/gt/shmem_utils.c
@@ -49,80 +49,40 @@ struct file *shmem_create_from_object(st
 	return file;
 }
 
-static size_t shmem_npte(struct file *file)
-{
-	return file->f_mapping->host->i_size >> PAGE_SHIFT;
-}
-
-static void __shmem_unpin_map(struct file *file, void *ptr, size_t n_pte)
-{
-	unsigned long pfn;
-
-	vunmap(ptr);
-
-	for (pfn = 0; pfn < n_pte; pfn++) {
-		struct page *page;
-
-		page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
-						   GFP_KERNEL);
-		if (!WARN_ON(IS_ERR(page))) {
-			put_page(page);
-			put_page(page);
-		}
-	}
-}
-
 void *shmem_pin_map(struct file *file)
 {
-	const size_t n_pte = shmem_npte(file);
-	pte_t *stack[32], **ptes, **mem;
-	struct vm_struct *area;
-	unsigned long pfn;
-
-	mem = stack;
-	if (n_pte > ARRAY_SIZE(stack)) {
-		mem = kvmalloc_array(n_pte, sizeof(*mem), GFP_KERNEL);
-		if (!mem)
-			return NULL;
-	}
-
-	area = alloc_vm_area(n_pte << PAGE_SHIFT, mem);
-	if (!area) {
-		if (mem != stack)
-			kvfree(mem);
+	struct page **pages;
+	size_t n_pages, i;
+	void *vaddr;
+
+	n_pages = file->f_mapping->host->i_size >> PAGE_SHIFT;
+	pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL);
+	if (!pages)
 		return NULL;
-	}
 
-	ptes = mem;
-	for (pfn = 0; pfn < n_pte; pfn++) {
-		struct page *page;
-
-		page = shmem_read_mapping_page_gfp(file->f_mapping, pfn,
-						   GFP_KERNEL);
-		if (IS_ERR(page))
+	for (i = 0; i < n_pages; i++) {
+		pages[i] = shmem_read_mapping_page_gfp(file->f_mapping, i,
+						       GFP_KERNEL);
+		if (IS_ERR(pages[i]))
 			goto err_page;
-
-		**ptes++ = mk_pte(page,  PAGE_KERNEL);
 	}
 
-	if (mem != stack)
-		kvfree(mem);
-
+	vaddr = vmap(pages, n_pages, VM_MAP_PUT_PAGES, PAGE_KERNEL);
+	if (!vaddr)
+		goto err_page;
 	mapping_set_unevictable(file->f_mapping);
-	return area->addr;
-
+	return vaddr;
 err_page:
-	if (mem != stack)
-		kvfree(mem);
-
-	__shmem_unpin_map(file, area->addr, pfn);
+	while (--i >= 0)
+		put_page(pages[i]);
+	kvfree(pages);
 	return NULL;
 }
 
 void shmem_unpin_map(struct file *file, void *ptr)
 {
 	mapping_clear_unevictable(file->f_mapping);
-	__shmem_unpin_map(file, ptr, shmem_npte(file));
+	vfree(ptr);
 }
 
 static int __shmem_rw(struct file *file, loff_t off,
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 33/40] drm/i915: stop using kmap in i915_gem_object_map
  2020-10-17 23:13 incoming Andrew Morton
                   ` (31 preceding siblings ...)
  2020-10-17 23:15 ` [patch 32/40] drm/i915: use vmap in shmem_pin_map Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 34/40] drm/i915: use vmap " Andrew Morton
                   ` (6 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: drm/i915: stop using kmap in i915_gem_object_map

kmap for !PageHighmem is just a convoluted way to say page_address, and
kunmap is a no-op in that case.

Link: https://lkml.kernel.org/r/20201002122204.1534411-8-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/gpu/drm/i915/gem/i915_gem_pages.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c~drm-i915-stop-using-kmap-in-i915_gem_object_map
+++ a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -162,8 +162,6 @@ static void unmap_object(struct drm_i915
 {
 	if (is_vmalloc_addr(ptr))
 		vunmap(ptr);
-	else
-		kunmap(kmap_to_page(ptr));
 }
 
 struct sg_table *
@@ -277,11 +275,10 @@ static void *i915_gem_object_map(struct
 		 * forever.
 		 *
 		 * So if the page is beyond the 32b boundary, make an explicit
-		 * vmap. On 64b, this check will be optimised away as we can
-		 * directly kmap any page on the system.
+		 * vmap.
 		 */
 		if (!PageHighMem(page))
-			return kmap(page);
+			return page_address(page);
 	}
 
 	mem = stack;
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 34/40] drm/i915: use vmap in i915_gem_object_map
  2020-10-17 23:13 incoming Andrew Morton
                   ` (32 preceding siblings ...)
  2020-10-17 23:15 ` [patch 33/40] drm/i915: stop using kmap in i915_gem_object_map Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 35/40] xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv Andrew Morton
                   ` (5 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: drm/i915: use vmap in i915_gem_object_map

i915_gem_object_map implements fairly low-level vmap functionality in a
driver.  Split it into two helpers, one for remapping kernel memory which
can use vmap, and one for I/O memory that uses vmap_pfn.

The only practical difference is that alloc_vm_area prefeaults the vmalloc
area PTEs, which doesn't seem to be required here for the kernel memory
case (and could be added to vmap using a flag if actually required).

Link: https://lkml.kernel.org/r/20201002122204.1534411-9-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/gpu/drm/i915/Kconfig              |    1 
 drivers/gpu/drm/i915/gem/i915_gem_pages.c |  129 +++++++++-----------
 2 files changed, 61 insertions(+), 69 deletions(-)

--- a/drivers/gpu/drm/i915/gem/i915_gem_pages.c~drm-i915-use-vmap-in-i915_gem_object_map
+++ a/drivers/gpu/drm/i915/gem/i915_gem_pages.c
@@ -232,34 +232,21 @@ unlock:
 	return err;
 }
 
-static inline pte_t iomap_pte(resource_size_t base,
-			      dma_addr_t offset,
-			      pgprot_t prot)
-{
-	return pte_mkspecial(pfn_pte((base + offset) >> PAGE_SHIFT, prot));
-}
-
 /* The 'mapping' part of i915_gem_object_pin_map() below */
-static void *i915_gem_object_map(struct drm_i915_gem_object *obj,
-				 enum i915_map_type type)
+static void *i915_gem_object_map_page(struct drm_i915_gem_object *obj,
+		enum i915_map_type type)
 {
-	unsigned long n_pte = obj->base.size >> PAGE_SHIFT;
-	struct sg_table *sgt = obj->mm.pages;
-	pte_t *stack[32], **mem;
-	struct vm_struct *area;
+	unsigned long n_pages = obj->base.size >> PAGE_SHIFT, i;
+	struct page *stack[32], **pages = stack, *page;
+	struct sgt_iter iter;
 	pgprot_t pgprot;
+	void *vaddr;
 
-	if (!i915_gem_object_has_struct_page(obj) && type != I915_MAP_WC)
-		return NULL;
-
-	if (GEM_WARN_ON(type == I915_MAP_WC &&
-			!static_cpu_has(X86_FEATURE_PAT)))
-		return NULL;
-
-	/* A single page can always be kmapped */
-	if (n_pte == 1 && type == I915_MAP_WB) {
-		struct page *page = sg_page(sgt->sgl);
-
+	switch (type) {
+	default:
+		MISSING_CASE(type);
+		fallthrough;	/* to use PAGE_KERNEL anyway */
+	case I915_MAP_WB:
 		/*
 		 * On 32b, highmem using a finite set of indirect PTE (i.e.
 		 * vmap) to provide virtual mappings of the high pages.
@@ -277,30 +264,8 @@ static void *i915_gem_object_map(struct
 		 * So if the page is beyond the 32b boundary, make an explicit
 		 * vmap.
 		 */
-		if (!PageHighMem(page))
-			return page_address(page);
-	}
-
-	mem = stack;
-	if (n_pte > ARRAY_SIZE(stack)) {
-		/* Too big for stack -- allocate temporary array instead */
-		mem = kvmalloc_array(n_pte, sizeof(*mem), GFP_KERNEL);
-		if (!mem)
-			return NULL;
-	}
-
-	area = alloc_vm_area(obj->base.size, mem);
-	if (!area) {
-		if (mem != stack)
-			kvfree(mem);
-		return NULL;
-	}
-
-	switch (type) {
-	default:
-		MISSING_CASE(type);
-		fallthrough;	/* to use PAGE_KERNEL anyway */
-	case I915_MAP_WB:
+		if (n_pages == 1 && !PageHighMem(sg_page(obj->mm.pages->sgl)))
+			return page_address(sg_page(obj->mm.pages->sgl));
 		pgprot = PAGE_KERNEL;
 		break;
 	case I915_MAP_WC:
@@ -308,30 +273,50 @@ static void *i915_gem_object_map(struct
 		break;
 	}
 
-	if (i915_gem_object_has_struct_page(obj)) {
-		struct sgt_iter iter;
-		struct page *page;
-		pte_t **ptes = mem;
-
-		for_each_sgt_page(page, iter, sgt)
-			**ptes++ = mk_pte(page, pgprot);
-	} else {
-		resource_size_t iomap;
-		struct sgt_iter iter;
-		pte_t **ptes = mem;
-		dma_addr_t addr;
+	if (n_pages > ARRAY_SIZE(stack)) {
+		/* Too big for stack -- allocate temporary array instead */
+		pages = kvmalloc_array(n_pages, sizeof(*pages), GFP_KERNEL);
+		if (!pages)
+			return NULL;
+	}
 
-		iomap = obj->mm.region->iomap.base;
-		iomap -= obj->mm.region->region.start;
+	i = 0;
+	for_each_sgt_page(page, iter, obj->mm.pages)
+		pages[i++] = page;
+	vaddr = vmap(pages, n_pages, 0, pgprot);
+	if (pages != stack)
+		kvfree(pages);
+	return vaddr;
+}
 
-		for_each_sgt_daddr(addr, iter, sgt)
-			**ptes++ = iomap_pte(iomap, addr, pgprot);
-	}
+static void *i915_gem_object_map_pfn(struct drm_i915_gem_object *obj,
+		enum i915_map_type type)
+{
+	resource_size_t iomap = obj->mm.region->iomap.base -
+		obj->mm.region->region.start;
+	unsigned long n_pfn = obj->base.size >> PAGE_SHIFT;
+	unsigned long stack[32], *pfns = stack, i;
+	struct sgt_iter iter;
+	dma_addr_t addr;
+	void *vaddr;
 
-	if (mem != stack)
-		kvfree(mem);
+	if (type != I915_MAP_WC)
+		return NULL;
+
+	if (n_pfn > ARRAY_SIZE(stack)) {
+		/* Too big for stack -- allocate temporary array instead */
+		pfns = kvmalloc_array(n_pfn, sizeof(*pfns), GFP_KERNEL);
+		if (!pfns)
+			return NULL;
+	}
 
-	return area->addr;
+	i = 0;
+	for_each_sgt_daddr(addr, iter, obj->mm.pages)
+		pfns[i++] = (iomap + addr) >> PAGE_SHIFT;
+	vaddr = vmap_pfn(pfns, n_pfn, pgprot_writecombine(PAGE_KERNEL_IO));
+	if (pfns != stack)
+		kvfree(pfns);
+	return vaddr;
 }
 
 /* get, pin, and map the pages of the object into kernel space */
@@ -383,7 +368,13 @@ void *i915_gem_object_pin_map(struct drm
 	}
 
 	if (!ptr) {
-		ptr = i915_gem_object_map(obj, type);
+		if (GEM_WARN_ON(type == I915_MAP_WC &&
+				!static_cpu_has(X86_FEATURE_PAT)))
+			ptr = NULL;
+		else if (i915_gem_object_has_struct_page(obj))
+			ptr = i915_gem_object_map_page(obj, type);
+		else
+			ptr = i915_gem_object_map_pfn(obj, type);
 		if (!ptr) {
 			err = -ENOMEM;
 			goto err_unpin;
--- a/drivers/gpu/drm/i915/Kconfig~drm-i915-use-vmap-in-i915_gem_object_map
+++ a/drivers/gpu/drm/i915/Kconfig
@@ -25,6 +25,7 @@ config DRM_I915
 	select CRC32
 	select SND_HDA_I915 if SND_HDA_CORE
 	select CEC_CORE if CEC_NOTIFIER
+	select VMAP_PFN
 	help
 	  Choose this option if you have a system that has "Intel Graphics
 	  Media Accelerator" or "HD Graphics" integrated graphics,
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 35/40] xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv
  2020-10-17 23:13 incoming Andrew Morton
                   ` (33 preceding siblings ...)
  2020-10-17 23:15 ` [patch 34/40] drm/i915: use vmap " Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 36/40] x86/xen: open code alloc_vm_area in arch_gnttab_valloc Andrew Morton
                   ` (4 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv

Replacing alloc_vm_area with get_vm_area_caller + apply_page_range allows
to fill put the phys_addr values directly instead of doing another loop
over all addresses.

Link: https://lkml.kernel.org/r/20201002122204.1534411-10-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 drivers/xen/xenbus/xenbus_client.c |   30 ++++++++++++++-------------
 1 file changed, 16 insertions(+), 14 deletions(-)

--- a/drivers/xen/xenbus/xenbus_client.c~xen-xenbus-use-apply_to_page_range-directly-in-xenbus_map_ring_pv
+++ a/drivers/xen/xenbus/xenbus_client.c
@@ -73,16 +73,13 @@ struct map_ring_valloc {
 	struct xenbus_map_node *node;
 
 	/* Why do we need two arrays? See comment of __xenbus_map_ring */
-	union {
-		unsigned long addrs[XENBUS_MAX_RING_GRANTS];
-		pte_t *ptes[XENBUS_MAX_RING_GRANTS];
-	};
+	unsigned long addrs[XENBUS_MAX_RING_GRANTS];
 	phys_addr_t phys_addrs[XENBUS_MAX_RING_GRANTS];
 
 	struct gnttab_map_grant_ref map[XENBUS_MAX_RING_GRANTS];
 	struct gnttab_unmap_grant_ref unmap[XENBUS_MAX_RING_GRANTS];
 
-	unsigned int idx;	/* HVM only. */
+	unsigned int idx;
 };
 
 static DEFINE_SPINLOCK(xenbus_valloc_lock);
@@ -686,6 +683,14 @@ int xenbus_unmap_ring_vfree(struct xenbu
 EXPORT_SYMBOL_GPL(xenbus_unmap_ring_vfree);
 
 #ifdef CONFIG_XEN_PV
+static int map_ring_apply(pte_t *pte, unsigned long addr, void *data)
+{
+	struct map_ring_valloc *info = data;
+
+	info->phys_addrs[info->idx++] = arbitrary_virt_to_machine(pte).maddr;
+	return 0;
+}
+
 static int xenbus_map_ring_pv(struct xenbus_device *dev,
 			      struct map_ring_valloc *info,
 			      grant_ref_t *gnt_refs,
@@ -694,18 +699,15 @@ static int xenbus_map_ring_pv(struct xen
 {
 	struct xenbus_map_node *node = info->node;
 	struct vm_struct *area;
-	int err = GNTST_okay;
-	int i;
-	bool leaked;
+	bool leaked = false;
+	int err = -ENOMEM;
 
-	area = alloc_vm_area(XEN_PAGE_SIZE * nr_grefs, info->ptes);
+	area = get_vm_area(XEN_PAGE_SIZE * nr_grefs, VM_IOREMAP);
 	if (!area)
 		return -ENOMEM;
-
-	for (i = 0; i < nr_grefs; i++)
-		info->phys_addrs[i] =
-			arbitrary_virt_to_machine(info->ptes[i]).maddr;
-
+	if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
+				XEN_PAGE_SIZE * nr_grefs, map_ring_apply, info))
+		goto failed;
 	err = __xenbus_map_ring(dev, gnt_refs, nr_grefs, node->handles,
 				info, GNTMAP_host_map | GNTMAP_contains_pte,
 				&leaked);
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 36/40] x86/xen: open code alloc_vm_area in arch_gnttab_valloc
  2020-10-17 23:13 incoming Andrew Morton
                   ` (34 preceding siblings ...)
  2020-10-17 23:15 ` [patch 35/40] xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 37/40] mm: remove alloc_vm_area Andrew Morton
                   ` (3 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: x86/xen: open code alloc_vm_area in arch_gnttab_valloc

Replace the last call to alloc_vm_area with an open coded version using an
iterator in struct gnttab_vm_area instead of the triple indirection magic
in alloc_vm_area.

Link: https://lkml.kernel.org/r/20201002122204.1534411-11-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/x86/xen/grant-table.c |   27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)

--- a/arch/x86/xen/grant-table.c~x86-xen-open-code-alloc_vm_area-in-arch_gnttab_valloc
+++ a/arch/x86/xen/grant-table.c
@@ -25,6 +25,7 @@
 static struct gnttab_vm_area {
 	struct vm_struct *area;
 	pte_t **ptes;
+	int idx;
 } gnttab_shared_vm_area, gnttab_status_vm_area;
 
 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
@@ -90,19 +91,31 @@ void arch_gnttab_unmap(void *shared, uns
 	}
 }
 
+static int gnttab_apply(pte_t *pte, unsigned long addr, void *data)
+{
+	struct gnttab_vm_area *area = data;
+
+	area->ptes[area->idx++] = pte;
+	return 0;
+}
+
 static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
 {
 	area->ptes = kmalloc_array(nr_frames, sizeof(*area->ptes), GFP_KERNEL);
 	if (area->ptes == NULL)
 		return -ENOMEM;
-
-	area->area = alloc_vm_area(PAGE_SIZE * nr_frames, area->ptes);
-	if (area->area == NULL) {
-		kfree(area->ptes);
-		return -ENOMEM;
-	}
-
+	area->area = get_vm_area(PAGE_SIZE * nr_frames, VM_IOREMAP);
+	if (!area->area)
+		goto out_free_ptes;
+	if (apply_to_page_range(&init_mm, (unsigned long)area->area->addr,
+			PAGE_SIZE * nr_frames, gnttab_apply, area))
+		goto out_free_vm_area;
 	return 0;
+out_free_vm_area:
+	free_vm_area(area->area);
+out_free_ptes:
+	kfree(area->ptes);
+	return -ENOMEM;
 }
 
 static void arch_gnttab_vfree(struct gnttab_vm_area *area)
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 37/40] mm: remove alloc_vm_area
  2020-10-17 23:13 incoming Andrew Morton
                   ` (35 preceding siblings ...)
  2020-10-17 23:15 ` [patch 36/40] x86/xen: open code alloc_vm_area in arch_gnttab_valloc Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 38/40] mm: cleanup the gfp_mask handling in __vmalloc_area_node Andrew Morton
                   ` (2 subsequent siblings)
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, boris.ostrovsky, chris, hch, jani.nikula, jgross,
	joonas.lahtinen, linux-mm, matthew.auld, minchan, mm-commits,
	ngupta, peterz, rodrigo.vivi, sstabellini, torvalds,
	tvrtko.ursulin, urezki, willy

From: Christoph Hellwig <hch@lst.de>
Subject: mm: remove alloc_vm_area

All users are gone now.

Link: https://lkml.kernel.org/r/20201002122204.1534411-12-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Stefano Stabellini <sstabellini@kernel.org>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 include/linux/vmalloc.h |    5 ---
 mm/nommu.c              |    7 -----
 mm/vmalloc.c            |   48 --------------------------------------
 3 files changed, 1 insertion(+), 59 deletions(-)

--- a/include/linux/vmalloc.h~mm-remove-alloc_vm_area
+++ a/include/linux/vmalloc.h
@@ -169,6 +169,7 @@ extern struct vm_struct *__get_vm_area_c
 					unsigned long flags,
 					unsigned long start, unsigned long end,
 					const void *caller);
+void free_vm_area(struct vm_struct *area);
 extern struct vm_struct *remove_vm_area(const void *addr);
 extern struct vm_struct *find_vm_area(const void *addr);
 
@@ -204,10 +205,6 @@ static inline void set_vm_flush_reset_pe
 }
 #endif
 
-/* Allocate/destroy a 'vmalloc' VM area. */
-extern struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes);
-extern void free_vm_area(struct vm_struct *area);
-
 /* for /dev/kmem */
 extern long vread(char *buf, char *addr, unsigned long count);
 extern long vwrite(char *buf, char *addr, unsigned long count);
--- a/mm/nommu.c~mm-remove-alloc_vm_area
+++ a/mm/nommu.c
@@ -354,13 +354,6 @@ void vm_unmap_aliases(void)
 }
 EXPORT_SYMBOL_GPL(vm_unmap_aliases);
 
-struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
-{
-	BUG();
-	return NULL;
-}
-EXPORT_SYMBOL_GPL(alloc_vm_area);
-
 void free_vm_area(struct vm_struct *area)
 {
 	BUG();
--- a/mm/vmalloc.c~mm-remove-alloc_vm_area
+++ a/mm/vmalloc.c
@@ -3083,54 +3083,6 @@ int remap_vmalloc_range(struct vm_area_s
 }
 EXPORT_SYMBOL(remap_vmalloc_range);
 
-static int f(pte_t *pte, unsigned long addr, void *data)
-{
-	pte_t ***p = data;
-
-	if (p) {
-		*(*p) = pte;
-		(*p)++;
-	}
-	return 0;
-}
-
-/**
- * alloc_vm_area - allocate a range of kernel address space
- * @size:	   size of the area
- * @ptes:	   returns the PTEs for the address space
- *
- * Returns:	NULL on failure, vm_struct on success
- *
- * This function reserves a range of kernel address space, and
- * allocates pagetables to map that range.  No actual mappings
- * are created.
- *
- * If @ptes is non-NULL, pointers to the PTEs (in init_mm)
- * allocated for the VM area are returned.
- */
-struct vm_struct *alloc_vm_area(size_t size, pte_t **ptes)
-{
-	struct vm_struct *area;
-
-	area = get_vm_area_caller(size, VM_IOREMAP,
-				__builtin_return_address(0));
-	if (area == NULL)
-		return NULL;
-
-	/*
-	 * This ensures that page tables are constructed for this region
-	 * of kernel virtual address space and mapped into init_mm.
-	 */
-	if (apply_to_page_range(&init_mm, (unsigned long)area->addr,
-				size, f, ptes ? &ptes : NULL)) {
-		free_vm_area(area);
-		return NULL;
-	}
-
-	return area;
-}
-EXPORT_SYMBOL_GPL(alloc_vm_area);
-
 void free_vm_area(struct vm_struct *area)
 {
 	struct vm_struct *ret;
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 38/40] mm: cleanup the gfp_mask handling in __vmalloc_area_node
  2020-10-17 23:13 incoming Andrew Morton
                   ` (36 preceding siblings ...)
  2020-10-17 23:15 ` [patch 37/40] mm: remove alloc_vm_area Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 39/40] mm: remove the filename in the top of file comment in vmalloc.c Andrew Morton
  2020-10-17 23:15 ` [patch 40/40] mm: remove duplicate include statement in mmu.c Andrew Morton
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, hch, linux-mm, mm-commits, torvalds, urezki

From: Christoph Hellwig <hch@lst.de>
Subject: mm: cleanup the gfp_mask handling in __vmalloc_area_node

Patch series "two small vmalloc cleanups".

This patch (of 2):

__vmalloc_area_node currently has four different gfp_t variables to
just express this simple logic:

 - use the passed in mask, plus __GFP_NOWARN and __GFP_HIGHMEM (if
   suitable) for the underlying page allocation
 - use just the reclaim flags from the passed in mask plus __GFP_ZERO
   for allocating the page array

Simplify this down to just use the pre-existing nested_gfp as-is for
the page array allocation, and just the passed in gfp_mask for the
page allocation, after conditionally ORing __GFP_HIGHMEM into it.  This
also makes the allocation warning a little more correct.

Also initialize two variables at the time of declaration while touching
this area.

Link: https://lkml.kernel.org/r/20201002124035.1539300-1-hch@lst.de
Link: https://lkml.kernel.org/r/20201002124035.1539300-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |   22 ++++++++++------------
 1 file changed, 10 insertions(+), 12 deletions(-)

--- a/mm/vmalloc.c~mm-cleanup-the-gfp_mask-handling-in-__vmalloc_area_node
+++ a/mm/vmalloc.c
@@ -2461,21 +2461,19 @@ EXPORT_SYMBOL_GPL(vmap_pfn);
 static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask,
 				 pgprot_t prot, int node)
 {
-	struct page **pages;
-	unsigned int nr_pages, array_size, i;
 	const gfp_t nested_gfp = (gfp_mask & GFP_RECLAIM_MASK) | __GFP_ZERO;
-	const gfp_t alloc_mask = gfp_mask | __GFP_NOWARN;
-	const gfp_t highmem_mask = (gfp_mask & (GFP_DMA | GFP_DMA32)) ?
-					0 :
-					__GFP_HIGHMEM;
+	unsigned int nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
+	unsigned int array_size = nr_pages * sizeof(struct page *), i;
+	struct page **pages;
 
-	nr_pages = get_vm_area_size(area) >> PAGE_SHIFT;
-	array_size = (nr_pages * sizeof(struct page *));
+	gfp_mask |= __GFP_NOWARN;
+	if (!(gfp_mask & (GFP_DMA | GFP_DMA32)))
+		gfp_mask |= __GFP_HIGHMEM;
 
 	/* Please note that the recursion is strictly bounded. */
 	if (array_size > PAGE_SIZE) {
-		pages = __vmalloc_node(array_size, 1, nested_gfp|highmem_mask,
-				node, area->caller);
+		pages = __vmalloc_node(array_size, 1, nested_gfp, node,
+					area->caller);
 	} else {
 		pages = kmalloc_node(array_size, nested_gfp, node);
 	}
@@ -2493,9 +2491,9 @@ static void *__vmalloc_area_node(struct
 		struct page *page;
 
 		if (node == NUMA_NO_NODE)
-			page = alloc_page(alloc_mask|highmem_mask);
+			page = alloc_page(gfp_mask);
 		else
-			page = alloc_pages_node(node, alloc_mask|highmem_mask, 0);
+			page = alloc_pages_node(node, gfp_mask, 0);
 
 		if (unlikely(!page)) {
 			/* Successfully allocated i pages, free them in __vfree() */
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 39/40] mm: remove the filename in the top of file comment in vmalloc.c
  2020-10-17 23:13 incoming Andrew Morton
                   ` (37 preceding siblings ...)
  2020-10-17 23:15 ` [patch 38/40] mm: cleanup the gfp_mask handling in __vmalloc_area_node Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  2020-10-17 23:15 ` [patch 40/40] mm: remove duplicate include statement in mmu.c Andrew Morton
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, hch, linux-mm, mm-commits, torvalds, urezki

From: Christoph Hellwig <hch@lst.de>
Subject: mm: remove the filename in the top of file comment in vmalloc.c

No point in having the filename inside the file.

Link: https://lkml.kernel.org/r/20201002124035.1539300-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/vmalloc.c |    2 --
 1 file changed, 2 deletions(-)

--- a/mm/vmalloc.c~mm-remove-the-filename-in-the-top-of-file-comment-in-vmallocc
+++ a/mm/vmalloc.c
@@ -1,7 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- *  linux/mm/vmalloc.c
- *
  *  Copyright (C) 1993  Linus Torvalds
  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
  *  SMP-safe vmalloc/vfree/ioremap, Tigran Aivazian <tigran@veritas.com>, May 2000
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* [patch 40/40] mm: remove duplicate include statement in mmu.c
  2020-10-17 23:13 incoming Andrew Morton
                   ` (38 preceding siblings ...)
  2020-10-17 23:15 ` [patch 39/40] mm: remove the filename in the top of file comment in vmalloc.c Andrew Morton
@ 2020-10-17 23:15 ` Andrew Morton
  39 siblings, 0 replies; 52+ messages in thread
From: Andrew Morton @ 2020-10-17 23:15 UTC (permalink / raw)
  To: akpm, linux-mm, mm-commits, rppt, tiantao6, torvalds

From: Tian Tao <tiantao6@hisilicon.com>
Subject: mm: remove duplicate include statement in mmu.c

asm/sections.h is included more than once, Remove the one that isn't
necessary.

Link: https://lkml.kernel.org/r/1600088607-17327-1-git-send-email-tiantao6@hisilicon.com
Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
Reviewed-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm/mm/mmu.c |    1 -
 1 file changed, 1 deletion(-)

--- a/arch/arm/mm/mmu.c~mm-remove-duplicate-include-statement-in-mmuc
+++ a/arch/arm/mm/mmu.c
@@ -17,7 +17,6 @@
 
 #include <asm/cp15.h>
 #include <asm/cputype.h>
-#include <asm/sections.h>
 #include <asm/cachetype.h>
 #include <asm/fixmap.h>
 #include <asm/sections.h>
_


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages()
  2020-10-17 23:14 ` [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages() Andrew Morton
@ 2020-10-18  1:28   ` Jann Horn
  0 siblings, 0 replies; 52+ messages in thread
From: Jann Horn @ 2020-10-18  1:28 UTC (permalink / raw)
  To: Andrew Morton, Linus Torvalds
  Cc: Eric W. Biederman, Jason Gunthorpe, John Hubbard, Linux-MM,
	Mauro Carvalho Chehab, mm-commits, Sakari Ailus,
	Michel Lespinasse

On Sun, Oct 18, 2020 at 1:14 AM Andrew Morton <akpm@linux-foundation.org> wrote:
> From: Jann Horn <jannh@google.com>
> Subject: mm/gup: assert that the mmap lock is held in __get_user_pages()
>
> After having cleaned up all GUP callers (except for the atomisp staging
> driver, which currently gets mmap locking completely wrong [1]) to always
> ensure that they hold the mmap lock when calling into GUP (unless the mm
> is not yet globally visible), add an assertion to make sure it stays that
> way going forward.

Please hold this patch until the replacement for the previous patch in
the series (original patch
mmap-locking-api-dont-check-locking-if-the-mm-isnt-live-yet, which you
are already holding back, and which is replaced by the series
https://lore.kernel.org/linux-mm/20201016225713.1971256-1-jannh@google.com/
"Broad write-locking of nascent mm in execve") has gone into the mm
tree.

Otherwise I believe that this mmap_assert_lock() will cause new
lockdep warnings in places like copy_strings().

(Going forward, is there something I should do differently if a
similar issue happens again with a series of patches that has already
landed in the mm tree but where, after further discussion, parts
should be replaced?)


> [1] https://lore.kernel.org/lkml/CAG48ez3tZAb9JVhw4T5e-i=h2_DUZxfNRTDsagSRCVazNXx5qA@mail.gmail.com/
>
> Link: https://lkml.kernel.org/r/CAG48ez1GM==OnHpS=ghqZNJPn02FCDUEHc7GQmGRMXUD_aKudg@mail.gmail.com
> Signed-off-by: Jann Horn <jannh@google.com>
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Acked-by: Michel Lespinasse <walken@google.com>
> Cc: "Eric W . Biederman" <ebiederm@xmission.com>
> Cc: John Hubbard <jhubbard@nvidia.com>
> Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
> Cc: Sakari Ailus <sakari.ailus@linux.intel.com>
> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
> ---
>
>  mm/gup.c |    2 ++
>  1 file changed, 2 insertions(+)
>
> --- a/mm/gup.c~mm-gup-assert-that-the-mmap-lock-is-held-in-__get_user_pages
> +++ a/mm/gup.c
> @@ -1027,6 +1027,8 @@ static long __get_user_pages(struct mm_s
>         struct vm_area_struct *vma = NULL;
>         struct follow_page_context ctx = { NULL };
>
> +       mmap_assert_locked(mm);
> +
>         if (!nr_pages)
>                 return 0;
>
> _


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-17 23:14 ` [patch 16/40] selftests/vm: use a common gup_test.h Andrew Morton
@ 2020-10-18 16:18   ` Linus Torvalds
  2020-10-18 16:22     ` Linus Torvalds
  2020-10-18 18:50     ` John Hubbard
  0 siblings, 2 replies; 52+ messages in thread
From: Linus Torvalds @ 2020-10-18 16:18 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Jonathan Corbet, Jerome Glisse, John Hubbard, Linux-MM,
	mm-commits, Ralph Campbell, Shuah Khan

On Sat, Oct 17, 2020 at 4:14 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> --- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
> +++ a/mm/gup_test.c
> @@ -4,22 +4,7 @@
> +#include "../../../../mm/gup_test.h"
> +++ a/mm/gup_test.h

There is no way I'm applying a crazy patch like this.

That can't be right.

And even if it works, it *still* isn't right.

               Linus


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 16:18   ` Linus Torvalds
@ 2020-10-18 16:22     ` Linus Torvalds
  2020-10-18 18:50     ` John Hubbard
  1 sibling, 0 replies; 52+ messages in thread
From: Linus Torvalds @ 2020-10-18 16:22 UTC (permalink / raw)
  To: Andrew Morton
  Cc: Jonathan Corbet, Jerome Glisse, John Hubbard, Linux-MM,
	mm-commits, Ralph Campbell, Shuah Khan

On Sun, Oct 18, 2020 at 9:18 AM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Sat, Oct 17, 2020 at 4:14 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > --- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
> > +++ a/mm/gup_test.c
> > @@ -4,22 +4,7 @@
> > +#include "../../../../mm/gup_test.h"
> > +++ a/mm/gup_test.h
>
> There is no way I'm applying a crazy patch like this.
>
> That can't be right.
>
> And even if it works, it *still* isn't right.

.. and it looks like I'll have to drop all the other gup-test patches
too because this one is broken.

             Linus


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 16:18   ` Linus Torvalds
  2020-10-18 16:22     ` Linus Torvalds
@ 2020-10-18 18:50     ` John Hubbard
  2020-10-18 19:03       ` Matthew Wilcox
  1 sibling, 1 reply; 52+ messages in thread
From: John Hubbard @ 2020-10-18 18:50 UTC (permalink / raw)
  To: Linus Torvalds, Andrew Morton
  Cc: Jonathan Corbet, Jerome Glisse, Linux-MM, mm-commits,
	Ralph Campbell, Shuah Khan, Jason Gary Gunthorpe

On 10/18/20 9:18 AM, Linus Torvalds wrote:
> On Sat, Oct 17, 2020 at 4:14 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>>
>> --- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
>> +++ a/mm/gup_test.c
>> @@ -4,22 +4,7 @@
>> +#include "../../../../mm/gup_test.h"
>> +++ a/mm/gup_test.h
> 
> There is no way I'm applying a crazy patch like this.
> 
> That can't be right.
> 
> And even if it works, it *still* isn't right.
> 
>                 Linus
> 

I feel the same way about the ridiculous ../..'s in the include path. But that
seemed to be the accepted way (I even have an email that I'm trying to find, in
which someone confirmed that...ah here, it is [1], and I'm adding Jason to CC)
for the odd situation of sharing a header file between kernel and user space,
for the kselftest world.

If there's a different acceptable way, I'd be delighted to use that.

[1] https://lore.kernel.org/r/20200929163507.GV9916@ziepe.ca

thanks,
-- 
John Hubbard
NVIDIA


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 18:50     ` John Hubbard
@ 2020-10-18 19:03       ` Matthew Wilcox
  2020-10-18 19:12         ` John Hubbard
  0 siblings, 1 reply; 52+ messages in thread
From: Matthew Wilcox @ 2020-10-18 19:03 UTC (permalink / raw)
  To: John Hubbard
  Cc: Linus Torvalds, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On Sun, Oct 18, 2020 at 11:50:10AM -0700, John Hubbard wrote:
> On 10/18/20 9:18 AM, Linus Torvalds wrote:
> > On Sat, Oct 17, 2020 at 4:14 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> > > 
> > > --- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
> > > +++ a/mm/gup_test.c
> > > @@ -4,22 +4,7 @@
> > > +#include "../../../../mm/gup_test.h"
> > > +++ a/mm/gup_test.h
> > 
> > There is no way I'm applying a crazy patch like this.
> > 
> > That can't be right.
> > 
> > And even if it works, it *still* isn't right.
> > 
> >                 Linus
> > 
> 
> I feel the same way about the ridiculous ../..'s in the include path. But that
> seemed to be the accepted way (I even have an email that I'm trying to find, in
> which someone confirmed that...ah here, it is [1], and I'm adding Jason to CC)
> for the odd situation of sharing a header file between kernel and user space,
> for the kselftest world.
> 
> If there's a different acceptable way, I'd be delighted to use that.

See where it says:

CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)

Does adding an extra -I../../../../mm to that line not do the trick?


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 19:03       ` Matthew Wilcox
@ 2020-10-18 19:12         ` John Hubbard
  2020-10-18 19:33           ` Linus Torvalds
  0 siblings, 1 reply; 52+ messages in thread
From: John Hubbard @ 2020-10-18 19:12 UTC (permalink / raw)
  To: Matthew Wilcox
  Cc: Linus Torvalds, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On 10/18/20 12:03 PM, Matthew Wilcox wrote:
> On Sun, Oct 18, 2020 at 11:50:10AM -0700, John Hubbard wrote:
>> On 10/18/20 9:18 AM, Linus Torvalds wrote:
>>> On Sat, Oct 17, 2020 at 4:14 PM Andrew Morton <akpm@linux-foundation.org> wrote:
>>>>
>>>> --- a/mm/gup_test.c~selftests-vm-use-a-common-gup_testh
>>>> +++ a/mm/gup_test.c
>>>> @@ -4,22 +4,7 @@
>>>> +#include "../../../../mm/gup_test.h"
>>>> +++ a/mm/gup_test.h
>>>
>>> There is no way I'm applying a crazy patch like this.
>>>
>>> That can't be right.
>>>
>>> And even if it works, it *still* isn't right.
>>>
>>>                  Linus
>>>
>>
>> I feel the same way about the ridiculous ../..'s in the include path. But that
>> seemed to be the accepted way (I even have an email that I'm trying to find, in
>> which someone confirmed that...ah here, it is [1], and I'm adding Jason to CC)
>> for the odd situation of sharing a header file between kernel and user space,
>> for the kselftest world.
>>
>> If there's a different acceptable way, I'd be delighted to use that.
> 
> See where it says:
> 
> CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)
> 
> Does adding an extra -I../../../../mm to that line not do the trick?
> 

Yes, that works. Here's a differential patch on top of the series to change it
over:

diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
index a9332a7cf33f..350d37c21671 100644
--- a/tools/testing/selftests/vm/Makefile
+++ b/tools/testing/selftests/vm/Makefile
@@ -23,7 +23,7 @@ MACHINE ?= $(shell echo $(uname_M) | sed -e 's/aarch64.*/arm64/')
  # LDLIBS.
  MAKEFLAGS += --no-builtin-rules

-CFLAGS = -Wall -I ../../../../usr/include $(EXTRA_CFLAGS)
+CFLAGS = -Wall -I ../../../../usr/include -I ../../../../mm $(EXTRA_CFLAGS)
  LDLIBS = -lrt -lpthread
  TEST_GEN_FILES = compaction_test
  TEST_GEN_FILES += gup_test
diff --git a/tools/testing/selftests/vm/gup_test.c b/tools/testing/selftests/vm/gup_test.c
index 1bef28174f3f..a8adda6edb07 100644
--- a/tools/testing/selftests/vm/gup_test.c
+++ b/tools/testing/selftests/vm/gup_test.c
@@ -6,7 +6,7 @@
  #include <sys/mman.h>
  #include <sys/stat.h>
  #include <sys/types.h>
-#include "../../../../mm/gup_test.h"
+#include "gup_test.h"

  #define MB (1UL << 20)
  #define PAGE_SIZE sysconf(_SC_PAGESIZE)



thanks,
-- 
John Hubbard
NVIDIA


^ permalink raw reply related	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 19:12         ` John Hubbard
@ 2020-10-18 19:33           ` Linus Torvalds
  2020-10-18 19:48             ` John Hubbard
  0 siblings, 1 reply; 52+ messages in thread
From: Linus Torvalds @ 2020-10-18 19:33 UTC (permalink / raw)
  To: John Hubbard
  Cc: Matthew Wilcox, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On Sun, Oct 18, 2020 at 12:13 PM John Hubbard <jhubbard@nvidia.com> wrote:
>
> >
> > Does adding an extra -I../../../../mm to that line not do the trick?
> >
>
> Yes, that works. Here's a differential patch on top of the series to change it
> over:

Guys, you're looking at the wrong thing.

Inside the *tools* subdirectory, that "../../.." thing makes sense.
You're in tools/testing/selftests/vm, and those crazy ".." paths are
ok. Ugly, but ok.

But the thing I objected to wasn't that tools directory ugliness.

Let me repeat what I found completely and utterly unacceptable, and
what you don't seem to have noticed, and what your patch didn't fix or
touch:

+++ a/mm/gup_test.c
+#include "../../../../mm/gup_test.h"

Notice what directory it is in? Notice how "../../.." etc is
COMPLETELY UNACCEPTABLE GARBAGE.

                    Linus


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 19:33           ` Linus Torvalds
@ 2020-10-18 19:48             ` John Hubbard
  2020-10-20  4:13               ` John Hubbard
  0 siblings, 1 reply; 52+ messages in thread
From: John Hubbard @ 2020-10-18 19:48 UTC (permalink / raw)
  To: Linus Torvalds
  Cc: Matthew Wilcox, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On 10/18/20 12:33 PM, Linus Torvalds wrote:
> On Sun, Oct 18, 2020 at 12:13 PM John Hubbard <jhubbard@nvidia.com> wrote:
...

> Guys, you're looking at the wrong thing.
> 
> Inside the *tools* subdirectory, that "../../.." thing makes sense.
> You're in tools/testing/selftests/vm, and those crazy ".." paths are
> ok. Ugly, but ok.
> 
> But the thing I objected to wasn't that tools directory ugliness.
> 
> Let me repeat what I found completely and utterly unacceptable, and
> what you don't seem to have noticed, and what your patch didn't fix or
> touch:
> 
> +++ a/mm/gup_test.c
> +#include "../../../../mm/gup_test.h"
> 
> Notice what directory it is in? Notice how "../../.." etc is
> COMPLETELY UNACCEPTABLE GARBAGE.
> 
>                      Linus
> 

aha, yes. yuck. So can we please just fix it up like this? A quick compile
test shows that it does build as expected:

diff --git a/mm/gup_test.c b/mm/gup_test.c
index 32770656cc32..e4c396146e90 100644
--- a/mm/gup_test.c
+++ b/mm/gup_test.c
@@ -4,7 +4,7 @@
  #include <linux/uaccess.h>
  #include <linux/ktime.h>
  #include <linux/debugfs.h>
-#include "../../../../mm/gup_test.h"
+#include "gup_test.h"

  static void put_back_pages(unsigned int cmd, struct page **pages,
  			   unsigned long nr_pages, unsigned int gup_test_flags)



Meanwhile, I'll work on coming up with a rationalization for how I let that
mistake slip past me. I've got a teenager living under the same roof with me
here, so I'm routinely exposed to some truly inspirational ideas for excuses. :)


thanks,
-- 
John Hubbard
NVIDIA


^ permalink raw reply related	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-18 19:48             ` John Hubbard
@ 2020-10-20  4:13               ` John Hubbard
  2020-10-20 16:45                 ` Linus Torvalds
  0 siblings, 1 reply; 52+ messages in thread
From: John Hubbard @ 2020-10-20  4:13 UTC (permalink / raw)
  To: Linus Torvalds
  Cc: Matthew Wilcox, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On 10/18/20 12:48 PM, John Hubbard wrote:
> On 10/18/20 12:33 PM, Linus Torvalds wrote:
>> On Sun, Oct 18, 2020 at 12:13 PM John Hubbard <jhubbard@nvidia.com> wrote:
> ...
> 
>> Guys, you're looking at the wrong thing.
>>
>> Inside the *tools* subdirectory, that "../../.." thing makes sense.
>> You're in tools/testing/selftests/vm, and those crazy ".." paths are
>> ok. Ugly, but ok.
>>
>> But the thing I objected to wasn't that tools directory ugliness.
>>
>> Let me repeat what I found completely and utterly unacceptable, and
>> what you don't seem to have noticed, and what your patch didn't fix or
>> touch:
>>
>> +++ a/mm/gup_test.c
>> +#include "../../../../mm/gup_test.h"
>>
>> Notice what directory it is in? Notice how "../../.." etc is
>> COMPLETELY UNACCEPTABLE GARBAGE.
>>
>>                      Linus
>>
> 
> aha, yes. yuck. So can we please just fix it up like this? A quick compile
> test shows that it does build as expected:
> 
> diff --git a/mm/gup_test.c b/mm/gup_test.c
> index 32770656cc32..e4c396146e90 100644
> --- a/mm/gup_test.c
> +++ b/mm/gup_test.c
> @@ -4,7 +4,7 @@
>   #include <linux/uaccess.h>
>   #include <linux/ktime.h>
>   #include <linux/debugfs.h>
> -#include "../../../../mm/gup_test.h"
> +#include "gup_test.h"
> 
>   static void put_back_pages(unsigned int cmd, struct page **pages,
>                  unsigned long nr_pages, unsigned int gup_test_flags)
> 
> 

Also, if there is anything I can do to unblock this, such as sending a formal
patch, or an updated patch or patchset, please let me know. I realize that
this is a low-priority area, but it would still be nice to get it merged
and behind us.


thanks,
-- 
John Hubbard
NVIDIA


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-20  4:13               ` John Hubbard
@ 2020-10-20 16:45                 ` Linus Torvalds
  2020-10-20 18:45                   ` John Hubbard
  0 siblings, 1 reply; 52+ messages in thread
From: Linus Torvalds @ 2020-10-20 16:45 UTC (permalink / raw)
  To: John Hubbard
  Cc: Matthew Wilcox, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On Mon, Oct 19, 2020 at 9:13 PM John Hubbard <jhubbard@nvidia.com> wrote:
>
> Also, if there is anything I can do to unblock this, such as sending a formal
> patch, or an updated patch or patchset, please let me know. I realize that
> this is a low-priority area, but it would still be nice to get it merged
> and behind us.

So what happens when I notice something like this, I just drop it from
my queue, the policy being "this was clearly not ready to be sent to
Linus".

That doesn't mean that it's blacklisted, but it does mean that I don't
want to see it returned immediately with the superficial thing fixed
that I noticed.

That's partly because I feel that people need to take another look and
see if there was perhaps something else going on (if I found one small
thing, maybe there are others lurking).

But admittedly it's probably mostly because I really don't want to
feel like I'm the wall that people throw spaghetti at to see if it
sticks. By the time it came to me, it was supposed to be ready (unless
I'm actively part of the development of said feature of course - which
still happens occasionally, but on the whole is a vanishingly small
part of the stuff I merge).

So I do expect to see it again later in some patch submission, just
not right now.

                 Linus


^ permalink raw reply	[flat|nested] 52+ messages in thread

* Re: [patch 16/40] selftests/vm: use a common gup_test.h
  2020-10-20 16:45                 ` Linus Torvalds
@ 2020-10-20 18:45                   ` John Hubbard
  0 siblings, 0 replies; 52+ messages in thread
From: John Hubbard @ 2020-10-20 18:45 UTC (permalink / raw)
  To: Linus Torvalds
  Cc: Matthew Wilcox, Andrew Morton, Jonathan Corbet, Jerome Glisse,
	Linux-MM, mm-commits, Ralph Campbell, Shuah Khan,
	Jason Gary Gunthorpe

On 10/20/20 9:45 AM, Linus Torvalds wrote:
> On Mon, Oct 19, 2020 at 9:13 PM John Hubbard <jhubbard@nvidia.com> wrote:
>>
>> Also, if there is anything I can do to unblock this, such as sending a formal
>> patch, or an updated patch or patchset, please let me know. I realize that
>> this is a low-priority area, but it would still be nice to get it merged
>> and behind us.
> 
> So what happens when I notice something like this, I just drop it from
> my queue, the policy being "this was clearly not ready to be sent to
> Linus".
> 
> That doesn't mean that it's blacklisted, but it does mean that I don't
> want to see it returned immediately with the superficial thing fixed
> that I noticed.
> 
> That's partly because I feel that people need to take another look and
> see if there was perhaps something else going on (if I found one small
> thing, maybe there are others lurking).
> 
> But admittedly it's probably mostly because I really don't want to
> feel like I'm the wall that people throw spaghetti at to see if it
> sticks. By the time it came to me, it was supposed to be ready (unless
> I'm actively part of the development of said feature of course - which
> still happens occasionally, but on the whole is a vanishingly small
> part of the stuff I merge).
> 
> So I do expect to see it again later in some patch submission, just
> not right now.
> 
>                   Linus

Makes perfect sense. I was wondering if it was blacklisted or in purgatory
or what, but now I get it. Thanks for explaining that part of the flow.

I'll see if I can pick up some more reviews, during this next cycle.


thanks,
-- 
John Hubbard
NVIDIA


^ permalink raw reply	[flat|nested] 52+ messages in thread

end of thread, other threads:[~2020-10-20 18:45 UTC | newest]

Thread overview: 52+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-10-17 23:13 incoming Andrew Morton
2020-10-17 23:13 ` [patch 01/40] ia64: fix build error with !COREDUMP Andrew Morton
2020-10-17 23:13 ` [patch 02/40] mm, memcg: rework remote charging API to support nesting Andrew Morton
2020-10-17 23:13 ` [patch 03/40] mm: kmem: move memcg_kmem_bypass() calls to get_mem/obj_cgroup_from_current() Andrew Morton
2020-10-17 23:13 ` [patch 04/40] mm: kmem: remove redundant checks from get_obj_cgroup_from_current() Andrew Morton
2020-10-17 23:13 ` [patch 05/40] mm: kmem: prepare remote memcg charging infra for interrupt contexts Andrew Morton
2020-10-17 23:13 ` [patch 06/40] mm: kmem: enable kernel memcg accounting from " Andrew Morton
2020-10-17 23:13 ` [patch 07/40] mm/memory-failure: remove a wrapper for alloc_migration_target() Andrew Morton
2020-10-17 23:14 ` [patch 08/40] mm/memory_hotplug: " Andrew Morton
2020-10-17 23:14 ` [patch 09/40] mm/migrate: avoid possible unnecessary process right check in kernel_move_pages() Andrew Morton
2020-10-17 23:14 ` [patch 10/40] mm/mmap: add inline vma_next() for readability of mmap code Andrew Morton
2020-10-17 23:14 ` [patch 11/40] mm/mmap: add inline munmap_vma_range() for code readability Andrew Morton
2020-10-17 23:14 ` [patch 12/40] mm/gup_benchmark: take the mmap lock around GUP Andrew Morton
2020-10-17 23:14 ` [patch 13/40] binfmt_elf: take the mmap lock around find_extend_vma() Andrew Morton
2020-10-17 23:14 ` [patch 14/40] mm/gup: assert that the mmap lock is held in __get_user_pages() Andrew Morton
2020-10-18  1:28   ` Jann Horn
2020-10-17 23:14 ` [patch 15/40] mm/gup_benchmark: rename to mm/gup_test Andrew Morton
2020-10-17 23:14 ` [patch 16/40] selftests/vm: use a common gup_test.h Andrew Morton
2020-10-18 16:18   ` Linus Torvalds
2020-10-18 16:22     ` Linus Torvalds
2020-10-18 18:50     ` John Hubbard
2020-10-18 19:03       ` Matthew Wilcox
2020-10-18 19:12         ` John Hubbard
2020-10-18 19:33           ` Linus Torvalds
2020-10-18 19:48             ` John Hubbard
2020-10-20  4:13               ` John Hubbard
2020-10-20 16:45                 ` Linus Torvalds
2020-10-20 18:45                   ` John Hubbard
2020-10-17 23:14 ` [patch 17/40] selftests/vm: rename run_vmtests --> run_vmtests.sh Andrew Morton
2020-10-17 23:14 ` [patch 18/40] selftests/vm: minor cleanup: Makefile and gup_test.c Andrew Morton
2020-10-17 23:14 ` [patch 19/40] selftests/vm: only some gup_test items are really benchmarks Andrew Morton
2020-10-17 23:14 ` [patch 20/40] selftests/vm: gup_test: introduce the dump_pages() sub-test Andrew Morton
2020-10-17 23:14 ` [patch 21/40] selftests/vm: run_vmtests.sh: update and clean up gup_test invocation Andrew Morton
2020-10-17 23:14 ` [patch 22/40] selftests/vm: hmm-tests: remove the libhugetlbfs dependency Andrew Morton
2020-10-17 23:14 ` [patch 23/40] selftests/vm: 10x speedup for hmm-tests Andrew Morton
2020-10-17 23:14 ` [patch 24/40] mm/madvise: pass mm to do_madvise Andrew Morton
2020-10-17 23:14 ` [patch 25/40] pid: move pidfd_get_pid() to pid.c Andrew Morton
2020-10-17 23:14 ` [patch 26/40] mm/madvise: introduce process_madvise() syscall: an external memory hinting API Andrew Morton
2020-10-17 23:15 ` [patch 27/40] mm: update the documentation for vfree Andrew Morton
2020-10-17 23:15 ` [patch 28/40] mm: add a VM_MAP_PUT_PAGES flag for vmap Andrew Morton
2020-10-17 23:15 ` [patch 29/40] mm: add a vmap_pfn function Andrew Morton
2020-10-17 23:15 ` [patch 30/40] mm: allow a NULL fn callback in apply_to_page_range Andrew Morton
2020-10-17 23:15 ` [patch 31/40] zsmalloc: switch from alloc_vm_area to get_vm_area Andrew Morton
2020-10-17 23:15 ` [patch 32/40] drm/i915: use vmap in shmem_pin_map Andrew Morton
2020-10-17 23:15 ` [patch 33/40] drm/i915: stop using kmap in i915_gem_object_map Andrew Morton
2020-10-17 23:15 ` [patch 34/40] drm/i915: use vmap " Andrew Morton
2020-10-17 23:15 ` [patch 35/40] xen/xenbus: use apply_to_page_range directly in xenbus_map_ring_pv Andrew Morton
2020-10-17 23:15 ` [patch 36/40] x86/xen: open code alloc_vm_area in arch_gnttab_valloc Andrew Morton
2020-10-17 23:15 ` [patch 37/40] mm: remove alloc_vm_area Andrew Morton
2020-10-17 23:15 ` [patch 38/40] mm: cleanup the gfp_mask handling in __vmalloc_area_node Andrew Morton
2020-10-17 23:15 ` [patch 39/40] mm: remove the filename in the top of file comment in vmalloc.c Andrew Morton
2020-10-17 23:15 ` [patch 40/40] mm: remove duplicate include statement in mmu.c Andrew Morton

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