Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull mm updates from Andrew Morton:
 "The usual shower of singleton fixes and minor series all over MM,
  documented (hopefully adequately) in the respective changelogs.
  Notable series include:

   - Lucas Stach has provided some page-mapping cleanup/consolidation/
     maintainability work in the series "mm/treewide: Remove pXd_huge()
     API".

   - In the series "Allow migrate on protnone reference with
     MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
     MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
     one test.

   - In their series "Memory allocation profiling" Kent Overstreet and
     Suren Baghdasaryan have contributed a means of determining (via
     /proc/allocinfo) whereabouts in the kernel memory is being
     allocated: number of calls and amount of memory.

   - Matthew Wilcox has provided the series "Various significant MM
     patches" which does a number of rather unrelated things, but in
     largely similar code sites.

   - In his series "mm: page_alloc: freelist migratetype hygiene"
     Johannes Weiner has fixed the page allocator's handling of
     migratetype requests, with resulting improvements in compaction
     efficiency.

   - In the series "make the hugetlb migration strategy consistent"
     Baolin Wang has fixed a hugetlb migration issue, which should
     improve hugetlb allocation reliability.

   - Liu Shixin has hit an I/O meltdown caused by readahead in a
     memory-tight memcg. Addressed in the series "Fix I/O high when
     memory almost met memcg limit".

   - In the series "mm/filemap: optimize folio adding and splitting"
     Kairui Song has optimized pagecache insertion, yielding ~10%
     performance improvement in one test.

   - Baoquan He has cleaned up and consolidated the early zone
     initialization code in the series "mm/mm_init.c: refactor
     free_area_init_core()".

   - Baoquan has also redone some MM initializatio code in the series
     "mm/init: minor clean up and improvement".

   - MM helper cleanups from Christoph Hellwig in his series "remove
     follow_pfn".

   - More cleanups from Matthew Wilcox in the series "Various
     page->flags cleanups".

   - Vlastimil Babka has contributed maintainability improvements in the
     series "memcg_kmem hooks refactoring".

   - More folio conversions and cleanups in Matthew Wilcox's series:
	"Convert huge_zero_page to huge_zero_folio"
	"khugepaged folio conversions"
	"Remove page_idle and page_young wrappers"
	"Use folio APIs in procfs"
	"Clean up __folio_put()"
	"Some cleanups for memory-failure"
	"Remove page_mapping()"
	"More folio compat code removal"

   - David Hildenbrand chipped in with "fs/proc/task_mmu: convert
     hugetlb functions to work on folis".

   - Code consolidation and cleanup work related to GUP's handling of
     hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".

   - Rick Edgecombe has developed some fixes to stack guard gaps in the
     series "Cover a guard gap corner case".

   - Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
     series "mm/ksm: fix ksm exec support for prctl".

   - Baolin Wang has implemented NUMA balancing for multi-size THPs.
     This is a simple first-cut implementation for now. The series is
     "support multi-size THP numa balancing".

   - Cleanups to vma handling helper functions from Matthew Wilcox in
     the series "Unify vma_address and vma_pgoff_address".

   - Some selftests maintenance work from Dev Jain in the series
     "selftests/mm: mremap_test: Optimizations and style fixes".

   - Improvements to the swapping of multi-size THPs from Ryan Roberts
     in the series "Swap-out mTHP without splitting".

   - Kefeng Wang has significantly optimized the handling of arm64's
     permission page faults in the series
	"arch/mm/fault: accelerate pagefault when badaccess"
	"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"

   - GUP cleanups from David Hildenbrand in "mm/gup: consistently call
     it GUP-fast".

   - hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
     path to use struct vm_fault".

   - selftests build fixes from John Hubbard in the series "Fix
     selftests/mm build without requiring "make headers"".

   - Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
     series "Improved Memory Tier Creation for CPUless NUMA Nodes".
     Fixes the initialization code so that migration between different
     memory types works as intended.

   - David Hildenbrand has improved follow_pte() and fixed an errant
     driver in the series "mm: follow_pte() improvements and acrn
     follow_pte() fixes".

   - David also did some cleanup work on large folio mapcounts in his
     series "mm: mapcount for large folios + page_mapcount() cleanups".

   - Folio conversions in KSM in Alex Shi's series "transfer page to
     folio in KSM".

   - Barry Song has added some sysfs stats for monitoring multi-size
     THP's in the series "mm: add per-order mTHP alloc and swpout
     counters".

   - Some zswap cleanups from Yosry Ahmed in the series "zswap
     same-filled and limit checking cleanups".

   - Matthew Wilcox has been looking at buffer_head code and found the
     documentation to be lacking. The series is "Improve buffer head
     documentation".

   - Multi-size THPs get more work, this time from Lance Yang. His
     series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
     optimizes the freeing of these things.

   - Kemeng Shi has added more userspace-visible writeback
     instrumentation in the series "Improve visibility of writeback".

   - Kemeng Shi then sent some maintenance work on top in the series
     "Fix and cleanups to page-writeback".

   - Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
     the series "Improve anon_vma scalability for anon VMAs". Intel's
     test bot reported an improbable 3x improvement in one test.

   - SeongJae Park adds some DAMON feature work in the series
	"mm/damon: add a DAMOS filter type for page granularity access recheck"
	"selftests/damon: add DAMOS quota goal test"

   - Also some maintenance work in the series
	"mm/damon/paddr: simplify page level access re-check for pageout"
	"mm/damon: misc fixes and improvements"

   - David Hildenbrand has disabled some known-to-fail selftests ni the
     series "selftests: mm: cow: flag vmsplice() hugetlb tests as
     XFAIL".

   - memcg metadata storage optimizations from Shakeel Butt in "memcg:
     reduce memory consumption by memcg stats".

   - DAX fixes and maintenance work from Vishal Verma in the series
     "dax/bus.c: Fixups for dax-bus locking""

* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
  memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
  selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
  mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
  selftests: cgroup: add tests to verify the zswap writeback path
  mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
  mm/damon/core: fix return value from damos_wmark_metric_value
  mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
  selftests: cgroup: remove redundant enabling of memory controller
  Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
  Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
  Docs/mm/damon/design: use a list for supported filters
  Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
  Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
  selftests/damon: classify tests for functionalities and regressions
  selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
  selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
  selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
  mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
  selftests/damon: add a test for DAMOS quota goal
  ...

1 files changed, 283 insertions, 0 deletions

diff --git a/lib/codetag.c b/lib/codetag.c
new file mode 100644
index 000000000000..5ace625f2328
--- /dev/null
+++ b/lib/codetag.c
@@ -0,0 +1,283 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/codetag.h>
+#include <linux/idr.h>
+#include <linux/kallsyms.h>
+#include <linux/module.h>
+#include <linux/seq_buf.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+
+struct codetag_type {
+	struct list_head link;
+	unsigned int count;
+	struct idr mod_idr;
+	struct rw_semaphore mod_lock; /* protects mod_idr */
+	struct codetag_type_desc desc;
+};
+
+struct codetag_range {
+	struct codetag *start;
+	struct codetag *stop;
+};
+
+struct codetag_module {
+	struct module *mod;
+	struct codetag_range range;
+};
+
+static DEFINE_MUTEX(codetag_lock);
+static LIST_HEAD(codetag_types);
+
+void codetag_lock_module_list(struct codetag_type *cttype, bool lock)
+{
+	if (lock)
+		down_read(&cttype->mod_lock);
+	else
+		up_read(&cttype->mod_lock);
+}
+
+bool codetag_trylock_module_list(struct codetag_type *cttype)
+{
+	return down_read_trylock(&cttype->mod_lock) != 0;
+}
+
+struct codetag_iterator codetag_get_ct_iter(struct codetag_type *cttype)
+{
+	struct codetag_iterator iter = {
+		.cttype = cttype,
+		.cmod = NULL,
+		.mod_id = 0,
+		.ct = NULL,
+	};
+
+	return iter;
+}
+
+static inline struct codetag *get_first_module_ct(struct codetag_module *cmod)
+{
+	return cmod->range.start < cmod->range.stop ? cmod->range.start : NULL;
+}
+
+static inline
+struct codetag *get_next_module_ct(struct codetag_iterator *iter)
+{
+	struct codetag *res = (struct codetag *)
+			((char *)iter->ct + iter->cttype->desc.tag_size);
+
+	return res < iter->cmod->range.stop ? res : NULL;
+}
+
+struct codetag *codetag_next_ct(struct codetag_iterator *iter)
+{
+	struct codetag_type *cttype = iter->cttype;
+	struct codetag_module *cmod;
+	struct codetag *ct;
+
+	lockdep_assert_held(&cttype->mod_lock);
+
+	if (unlikely(idr_is_empty(&cttype->mod_idr)))
+		return NULL;
+
+	ct = NULL;
+	while (true) {
+		cmod = idr_find(&cttype->mod_idr, iter->mod_id);
+
+		/* If module was removed move to the next one */
+		if (!cmod)
+			cmod = idr_get_next_ul(&cttype->mod_idr,
+					       &iter->mod_id);
+
+		/* Exit if no more modules */
+		if (!cmod)
+			break;
+
+		if (cmod != iter->cmod) {
+			iter->cmod = cmod;
+			ct = get_first_module_ct(cmod);
+		} else
+			ct = get_next_module_ct(iter);
+
+		if (ct)
+			break;
+
+		iter->mod_id++;
+	}
+
+	iter->ct = ct;
+	return ct;
+}
+
+void codetag_to_text(struct seq_buf *out, struct codetag *ct)
+{
+	if (ct->modname)
+		seq_buf_printf(out, "%s:%u [%s] func:%s",
+			       ct->filename, ct->lineno,
+			       ct->modname, ct->function);
+	else
+		seq_buf_printf(out, "%s:%u func:%s",
+			       ct->filename, ct->lineno, ct->function);
+}
+
+static inline size_t range_size(const struct codetag_type *cttype,
+				const struct codetag_range *range)
+{
+	return ((char *)range->stop - (char *)range->start) /
+			cttype->desc.tag_size;
+}
+
+#ifdef CONFIG_MODULES
+static void *get_symbol(struct module *mod, const char *prefix, const char *name)
+{
+	DECLARE_SEQ_BUF(sb, KSYM_NAME_LEN);
+	const char *buf;
+	void *ret;
+
+	seq_buf_printf(&sb, "%s%s", prefix, name);
+	if (seq_buf_has_overflowed(&sb))
+		return NULL;
+
+	buf = seq_buf_str(&sb);
+	preempt_disable();
+	ret = mod ?
+		(void *)find_kallsyms_symbol_value(mod, buf) :
+		(void *)kallsyms_lookup_name(buf);
+	preempt_enable();
+
+	return ret;
+}
+
+static struct codetag_range get_section_range(struct module *mod,
+					      const char *section)
+{
+	return (struct codetag_range) {
+		get_symbol(mod, "__start_", section),
+		get_symbol(mod, "__stop_", section),
+	};
+}
+
+static int codetag_module_init(struct codetag_type *cttype, struct module *mod)
+{
+	struct codetag_range range;
+	struct codetag_module *cmod;
+	int err;
+
+	range = get_section_range(mod, cttype->desc.section);
+	if (!range.start || !range.stop) {
+		pr_warn("Failed to load code tags of type %s from the module %s\n",
+			cttype->desc.section,
+			mod ? mod->name : "(built-in)");
+		return -EINVAL;
+	}
+
+	/* Ignore empty ranges */
+	if (range.start == range.stop)
+		return 0;
+
+	BUG_ON(range.start > range.stop);
+
+	cmod = kmalloc(sizeof(*cmod), GFP_KERNEL);
+	if (unlikely(!cmod))
+		return -ENOMEM;
+
+	cmod->mod = mod;
+	cmod->range = range;
+
+	down_write(&cttype->mod_lock);
+	err = idr_alloc(&cttype->mod_idr, cmod, 0, 0, GFP_KERNEL);
+	if (err >= 0) {
+		cttype->count += range_size(cttype, &range);
+		if (cttype->desc.module_load)
+			cttype->desc.module_load(cttype, cmod);
+	}
+	up_write(&cttype->mod_lock);
+
+	if (err < 0) {
+		kfree(cmod);
+		return err;
+	}
+
+	return 0;
+}
+
+void codetag_load_module(struct module *mod)
+{
+	struct codetag_type *cttype;
+
+	if (!mod)
+		return;
+
+	mutex_lock(&codetag_lock);
+	list_for_each_entry(cttype, &codetag_types, link)
+		codetag_module_init(cttype, mod);
+	mutex_unlock(&codetag_lock);
+}
+
+bool codetag_unload_module(struct module *mod)
+{
+	struct codetag_type *cttype;
+	bool unload_ok = true;
+
+	if (!mod)
+		return true;
+
+	mutex_lock(&codetag_lock);
+	list_for_each_entry(cttype, &codetag_types, link) {
+		struct codetag_module *found = NULL;
+		struct codetag_module *cmod;
+		unsigned long mod_id, tmp;
+
+		down_write(&cttype->mod_lock);
+		idr_for_each_entry_ul(&cttype->mod_idr, cmod, tmp, mod_id) {
+			if (cmod->mod && cmod->mod == mod) {
+				found = cmod;
+				break;
+			}
+		}
+		if (found) {
+			if (cttype->desc.module_unload)
+				if (!cttype->desc.module_unload(cttype, cmod))
+					unload_ok = false;
+
+			cttype->count -= range_size(cttype, &cmod->range);
+			idr_remove(&cttype->mod_idr, mod_id);
+			kfree(cmod);
+		}
+		up_write(&cttype->mod_lock);
+	}
+	mutex_unlock(&codetag_lock);
+
+	return unload_ok;
+}
+
+#else /* CONFIG_MODULES */
+static int codetag_module_init(struct codetag_type *cttype, struct module *mod) { return 0; }
+#endif /* CONFIG_MODULES */
+
+struct codetag_type *
+codetag_register_type(const struct codetag_type_desc *desc)
+{
+	struct codetag_type *cttype;
+	int err;
+
+	BUG_ON(desc->tag_size <= 0);
+
+	cttype = kzalloc(sizeof(*cttype), GFP_KERNEL);
+	if (unlikely(!cttype))
+		return ERR_PTR(-ENOMEM);
+
+	cttype->desc = *desc;
+	idr_init(&cttype->mod_idr);
+	init_rwsem(&cttype->mod_lock);
+
+	err = codetag_module_init(cttype, NULL);
+	if (unlikely(err)) {
+		kfree(cttype);
+		return ERR_PTR(err);
+	}
+
+	mutex_lock(&codetag_lock);
+	list_add_tail(&cttype->link, &codetag_types);
+	mutex_unlock(&codetag_lock);
+
+	return cttype;
+}