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authorLinus Torvalds <torvalds@linux-foundation.org>2024-03-15 03:43:30 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2024-03-15 03:43:30 +0300
commit902861e34c401696ed9ad17a54c8790e7e8e3069 (patch)
tree126324c3ec4101b1e17f002ef029d3ffb296ada7 /mm/hugetlb.c
parent1bbeaf83dd7b5e3628b98bec66ff8fe2646e14aa (diff)
parent270700dd06ca41a4779c19eb46608f076bb7d40e (diff)
downloadlinux-902861e34c401696ed9ad17a54c8790e7e8e3069.tar.xz
Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton: - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames from hotplugged memory rather than only from main memory. Series "implement "memmap on memory" feature on s390". - More folio conversions from Matthew Wilcox in the series "Convert memcontrol charge moving to use folios" "mm: convert mm counter to take a folio" - Chengming Zhou has optimized zswap's rbtree locking, providing significant reductions in system time and modest but measurable reductions in overall runtimes. The series is "mm/zswap: optimize the scalability of zswap rb-tree". - Chengming Zhou has also provided the series "mm/zswap: optimize zswap lru list" which provides measurable runtime benefits in some swap-intensive situations. - And Chengming Zhou further optimizes zswap in the series "mm/zswap: optimize for dynamic zswap_pools". Measured improvements are modest. - zswap cleanups and simplifications from Yosry Ahmed in the series "mm: zswap: simplify zswap_swapoff()". - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has contributed several DAX cleanups as well as adding a sysfs tunable to control the memmap_on_memory setting when the dax device is hotplugged as system memory. - Johannes Weiner has added the large series "mm: zswap: cleanups", which does that. - More DAMON work from SeongJae Park in the series "mm/damon: make DAMON debugfs interface deprecation unignorable" "selftests/damon: add more tests for core functionalities and corner cases" "Docs/mm/damon: misc readability improvements" "mm/damon: let DAMOS feeds and tame/auto-tune itself" - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs extension" Rakie Kim has developed a new mempolicy interleaving policy wherein we allocate memory across nodes in a weighted fashion rather than uniformly. This is beneficial in heterogeneous memory environments appearing with CXL. - Christophe Leroy has contributed some cleanup and consolidation work against the ARM pagetable dumping code in the series "mm: ptdump: Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute". - Luis Chamberlain has added some additional xarray selftesting in the series "test_xarray: advanced API multi-index tests". - Muhammad Usama Anjum has reworked the selftest code to make its human-readable output conform to the TAP ("Test Anything Protocol") format. Amongst other things, this opens up the use of third-party tools to parse and process out selftesting results. - Ryan Roberts has added fork()-time PTE batching of THP ptes in the series "mm/memory: optimize fork() with PTE-mapped THP". Mainly targeted at arm64, this significantly speeds up fork() when the process has a large number of pte-mapped folios. - David Hildenbrand also gets in on the THP pte batching game in his series "mm/memory: optimize unmap/zap with PTE-mapped THP". It implements batching during munmap() and other pte teardown situations. The microbenchmark improvements are nice. - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte mappings"). Kernel build times on arm64 improved nicely. Ryan's series "Address some contpte nits" provides some followup work. - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has fixed an obscure hugetlb race which was causing unnecessary page faults. He has also added a reproducer under the selftest code. - In the series "selftests/mm: Output cleanups for the compaction test", Mark Brown did what the title claims. - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring". - Even more zswap material from Nhat Pham. The series "fix and extend zswap kselftests" does as claimed. - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in our handling of DAX on archiecctures which have virtually aliasing data caches. The arm architecture is the main beneficiary. - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic improvements in worst-case mmap_lock hold times during certain userfaultfd operations. - Some page_owner enhancements and maintenance work from Oscar Salvador in his series "page_owner: print stacks and their outstanding allocations" "page_owner: Fixup and cleanup" - Uladzislau Rezki has contributed some vmalloc scalability improvements in his series "Mitigate a vmap lock contention". It realizes a 12x improvement for a certain microbenchmark. - Some kexec/crash cleanup work from Baoquan He in the series "Split crash out from kexec and clean up related config items". - Some zsmalloc maintenance work from Chengming Zhou in the series "mm/zsmalloc: fix and optimize objects/page migration" "mm/zsmalloc: some cleanup for get/set_zspage_mapping()" - Zi Yan has taught the MM to perform compaction on folios larger than order=0. This a step along the path to implementaton of the merging of large anonymous folios. The series is named "Enable >0 order folio memory compaction". - Christoph Hellwig has done quite a lot of cleanup work in the pagecache writeback code in his series "convert write_cache_pages() to an iterator". - Some modest hugetlb cleanups and speedups in Vishal Moola's series "Handle hugetlb faults under the VMA lock". - Zi Yan has changed the page splitting code so we can split huge pages into sizes other than order-0 to better utilize large folios. The series is named "Split a folio to any lower order folios". - David Hildenbrand has contributed the series "mm: remove total_mapcount()", a cleanup. - Matthew Wilcox has sought to improve the performance of bulk memory freeing in his series "Rearrange batched folio freeing". - Gang Li's series "hugetlb: parallelize hugetlb page init on boot" provides large improvements in bootup times on large machines which are configured to use large numbers of hugetlb pages. - Matthew Wilcox's series "PageFlags cleanups" does that. - Qi Zheng's series "minor fixes and supplement for ptdesc" does that also. S390 is affected. - Cleanups to our pagemap utility functions from Peter Xu in his series "mm/treewide: Replace pXd_large() with pXd_leaf()". - Nico Pache has fixed a few things with our hugepage selftests in his series "selftests/mm: Improve Hugepage Test Handling in MM Selftests". - Also, of course, many singleton patches to many things. Please see the individual changelogs for details. * tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits) mm/zswap: remove the memcpy if acomp is not sleepable crypto: introduce: acomp_is_async to expose if comp drivers might sleep memtest: use {READ,WRITE}_ONCE in memory scanning mm: prohibit the last subpage from reusing the entire large folio mm: recover pud_leaf() definitions in nopmd case selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements selftests/mm: skip uffd hugetlb tests with insufficient hugepages selftests/mm: dont fail testsuite due to a lack of hugepages mm/huge_memory: skip invalid debugfs new_order input for folio split mm/huge_memory: check new folio order when split a folio mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure mm: add an explicit smp_wmb() to UFFDIO_CONTINUE mm: fix list corruption in put_pages_list mm: remove folio from deferred split list before uncharging it filemap: avoid unnecessary major faults in filemap_fault() mm,page_owner: drop unnecessary check mm,page_owner: check for null stack_record before bumping its refcount mm: swap: fix race between free_swap_and_cache() and swapoff() mm/treewide: align up pXd_leaf() retval across archs mm/treewide: drop pXd_large() ...
Diffstat (limited to 'mm/hugetlb.c')
-rw-r--r--mm/hugetlb.c414
1 files changed, 261 insertions, 153 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index ed1581b670d4..23ef240ba48a 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -35,6 +35,7 @@
#include <linux/delayacct.h>
#include <linux/memory.h>
#include <linux/mm_inline.h>
+#include <linux/padata.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
@@ -68,7 +69,7 @@ static bool hugetlb_cma_folio(struct folio *folio, unsigned int order)
#endif
static unsigned long hugetlb_cma_size __initdata;
-__initdata LIST_HEAD(huge_boot_pages);
+__initdata struct list_head huge_boot_pages[MAX_NUMNODES];
/* for command line parsing */
static struct hstate * __initdata parsed_hstate;
@@ -1464,15 +1465,15 @@ static int get_valid_node_allowed(int nid, nodemask_t *nodes_allowed)
* next node from which to allocate, handling wrap at end of node
* mask.
*/
-static int hstate_next_node_to_alloc(struct hstate *h,
+static int hstate_next_node_to_alloc(int *next_node,
nodemask_t *nodes_allowed)
{
int nid;
VM_BUG_ON(!nodes_allowed);
- nid = get_valid_node_allowed(h->next_nid_to_alloc, nodes_allowed);
- h->next_nid_to_alloc = next_node_allowed(nid, nodes_allowed);
+ nid = get_valid_node_allowed(*next_node, nodes_allowed);
+ *next_node = next_node_allowed(nid, nodes_allowed);
return nid;
}
@@ -1495,10 +1496,10 @@ static int hstate_next_node_to_free(struct hstate *h, nodemask_t *nodes_allowed)
return nid;
}
-#define for_each_node_mask_to_alloc(hs, nr_nodes, node, mask) \
+#define for_each_node_mask_to_alloc(next_node, nr_nodes, node, mask) \
for (nr_nodes = nodes_weight(*mask); \
nr_nodes > 0 && \
- ((node = hstate_next_node_to_alloc(hs, mask)) || 1); \
+ ((node = hstate_next_node_to_alloc(next_node, mask)) || 1); \
nr_nodes--)
#define for_each_node_mask_to_free(hs, nr_nodes, node, mask) \
@@ -2163,9 +2164,9 @@ static bool prep_compound_gigantic_folio_for_demote(struct folio *folio,
* transparent huge pages. See the PageTransHuge() documentation for more
* details.
*/
-int PageHuge(struct page *page)
+int PageHuge(const struct page *page)
{
- struct folio *folio;
+ const struct folio *folio;
if (!PageCompound(page))
return 0;
@@ -2350,12 +2351,13 @@ static void prep_and_add_allocated_folios(struct hstate *h,
*/
static struct folio *alloc_pool_huge_folio(struct hstate *h,
nodemask_t *nodes_allowed,
- nodemask_t *node_alloc_noretry)
+ nodemask_t *node_alloc_noretry,
+ int *next_node)
{
gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
int nr_nodes, node;
- for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) {
+ for_each_node_mask_to_alloc(next_node, nr_nodes, node, nodes_allowed) {
struct folio *folio;
folio = only_alloc_fresh_hugetlb_folio(h, gfp_mask, node,
@@ -3029,21 +3031,9 @@ static int alloc_and_dissolve_hugetlb_folio(struct hstate *h,
{
gfp_t gfp_mask = htlb_alloc_mask(h) | __GFP_THISNODE;
int nid = folio_nid(old_folio);
- struct folio *new_folio;
+ struct folio *new_folio = NULL;
int ret = 0;
- /*
- * Before dissolving the folio, we need to allocate a new one for the
- * pool to remain stable. Here, we allocate the folio and 'prep' it
- * by doing everything but actually updating counters and adding to
- * the pool. This simplifies and let us do most of the processing
- * under the lock.
- */
- new_folio = alloc_buddy_hugetlb_folio(h, gfp_mask, nid, NULL, NULL);
- if (!new_folio)
- return -ENOMEM;
- __prep_new_hugetlb_folio(h, new_folio);
-
retry:
spin_lock_irq(&hugetlb_lock);
if (!folio_test_hugetlb(old_folio)) {
@@ -3073,6 +3063,16 @@ retry:
cond_resched();
goto retry;
} else {
+ if (!new_folio) {
+ spin_unlock_irq(&hugetlb_lock);
+ new_folio = alloc_buddy_hugetlb_folio(h, gfp_mask, nid,
+ NULL, NULL);
+ if (!new_folio)
+ return -ENOMEM;
+ __prep_new_hugetlb_folio(h, new_folio);
+ goto retry;
+ }
+
/*
* Ok, old_folio is still a genuine free hugepage. Remove it from
* the freelist and decrease the counters. These will be
@@ -3100,9 +3100,11 @@ retry:
free_new:
spin_unlock_irq(&hugetlb_lock);
- /* Folio has a zero ref count, but needs a ref to be freed */
- folio_ref_unfreeze(new_folio, 1);
- update_and_free_hugetlb_folio(h, new_folio, false);
+ if (new_folio) {
+ /* Folio has a zero ref count, but needs a ref to be freed */
+ folio_ref_unfreeze(new_folio, 1);
+ update_and_free_hugetlb_folio(h, new_folio, false);
+ }
return ret;
}
@@ -3299,7 +3301,7 @@ int alloc_bootmem_huge_page(struct hstate *h, int nid)
int __alloc_bootmem_huge_page(struct hstate *h, int nid)
{
struct huge_bootmem_page *m = NULL; /* initialize for clang */
- int nr_nodes, node;
+ int nr_nodes, node = nid;
/* do node specific alloc */
if (nid != NUMA_NO_NODE) {
@@ -3310,7 +3312,7 @@ int __alloc_bootmem_huge_page(struct hstate *h, int nid)
goto found;
}
/* allocate from next node when distributing huge pages */
- for_each_node_mask_to_alloc(h, nr_nodes, node, &node_states[N_MEMORY]) {
+ for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, &node_states[N_MEMORY]) {
m = memblock_alloc_try_nid_raw(
huge_page_size(h), huge_page_size(h),
0, MEMBLOCK_ALLOC_ACCESSIBLE, node);
@@ -3337,7 +3339,7 @@ found:
huge_page_size(h) - PAGE_SIZE);
/* Put them into a private list first because mem_map is not up yet */
INIT_LIST_HEAD(&m->list);
- list_add(&m->list, &huge_boot_pages);
+ list_add(&m->list, &huge_boot_pages[node]);
m->hstate = h;
return 1;
}
@@ -3388,8 +3390,6 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h,
/* Send list for bulk vmemmap optimization processing */
hugetlb_vmemmap_optimize_folios(h, folio_list);
- /* Add all new pool pages to free lists in one lock cycle */
- spin_lock_irqsave(&hugetlb_lock, flags);
list_for_each_entry_safe(folio, tmp_f, folio_list, lru) {
if (!folio_test_hugetlb_vmemmap_optimized(folio)) {
/*
@@ -3402,23 +3402,25 @@ static void __init prep_and_add_bootmem_folios(struct hstate *h,
HUGETLB_VMEMMAP_RESERVE_PAGES,
pages_per_huge_page(h));
}
+ /* Subdivide locks to achieve better parallel performance */
+ spin_lock_irqsave(&hugetlb_lock, flags);
__prep_account_new_huge_page(h, folio_nid(folio));
enqueue_hugetlb_folio(h, folio);
+ spin_unlock_irqrestore(&hugetlb_lock, flags);
}
- spin_unlock_irqrestore(&hugetlb_lock, flags);
}
/*
* Put bootmem huge pages into the standard lists after mem_map is up.
* Note: This only applies to gigantic (order > MAX_PAGE_ORDER) pages.
*/
-static void __init gather_bootmem_prealloc(void)
+static void __init gather_bootmem_prealloc_node(unsigned long nid)
{
LIST_HEAD(folio_list);
struct huge_bootmem_page *m;
struct hstate *h = NULL, *prev_h = NULL;
- list_for_each_entry(m, &huge_boot_pages, list) {
+ list_for_each_entry(m, &huge_boot_pages[nid], list) {
struct page *page = virt_to_page(m);
struct folio *folio = (void *)page;
@@ -3451,6 +3453,31 @@ static void __init gather_bootmem_prealloc(void)
prep_and_add_bootmem_folios(h, &folio_list);
}
+static void __init gather_bootmem_prealloc_parallel(unsigned long start,
+ unsigned long end, void *arg)
+{
+ int nid;
+
+ for (nid = start; nid < end; nid++)
+ gather_bootmem_prealloc_node(nid);
+}
+
+static void __init gather_bootmem_prealloc(void)
+{
+ struct padata_mt_job job = {
+ .thread_fn = gather_bootmem_prealloc_parallel,
+ .fn_arg = NULL,
+ .start = 0,
+ .size = num_node_state(N_MEMORY),
+ .align = 1,
+ .min_chunk = 1,
+ .max_threads = num_node_state(N_MEMORY),
+ .numa_aware = true,
+ };
+
+ padata_do_multithreaded(&job);
+}
+
static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid)
{
unsigned long i;
@@ -3482,6 +3509,108 @@ static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid)
h->max_huge_pages_node[nid] = i;
}
+static bool __init hugetlb_hstate_alloc_pages_specific_nodes(struct hstate *h)
+{
+ int i;
+ bool node_specific_alloc = false;
+
+ for_each_online_node(i) {
+ if (h->max_huge_pages_node[i] > 0) {
+ hugetlb_hstate_alloc_pages_onenode(h, i);
+ node_specific_alloc = true;
+ }
+ }
+
+ return node_specific_alloc;
+}
+
+static void __init hugetlb_hstate_alloc_pages_errcheck(unsigned long allocated, struct hstate *h)
+{
+ if (allocated < h->max_huge_pages) {
+ char buf[32];
+
+ string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
+ pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n",
+ h->max_huge_pages, buf, allocated);
+ h->max_huge_pages = allocated;
+ }
+}
+
+static void __init hugetlb_pages_alloc_boot_node(unsigned long start, unsigned long end, void *arg)
+{
+ struct hstate *h = (struct hstate *)arg;
+ int i, num = end - start;
+ nodemask_t node_alloc_noretry;
+ LIST_HEAD(folio_list);
+ int next_node = first_online_node;
+
+ /* Bit mask controlling how hard we retry per-node allocations.*/
+ nodes_clear(node_alloc_noretry);
+
+ for (i = 0; i < num; ++i) {
+ struct folio *folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY],
+ &node_alloc_noretry, &next_node);
+ if (!folio)
+ break;
+
+ list_move(&folio->lru, &folio_list);
+ cond_resched();
+ }
+
+ prep_and_add_allocated_folios(h, &folio_list);
+}
+
+static unsigned long __init hugetlb_gigantic_pages_alloc_boot(struct hstate *h)
+{
+ unsigned long i;
+
+ for (i = 0; i < h->max_huge_pages; ++i) {
+ if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE))
+ break;
+ cond_resched();
+ }
+
+ return i;
+}
+
+static unsigned long __init hugetlb_pages_alloc_boot(struct hstate *h)
+{
+ struct padata_mt_job job = {
+ .fn_arg = h,
+ .align = 1,
+ .numa_aware = true
+ };
+
+ job.thread_fn = hugetlb_pages_alloc_boot_node;
+ job.start = 0;
+ job.size = h->max_huge_pages;
+
+ /*
+ * job.max_threads is twice the num_node_state(N_MEMORY),
+ *
+ * Tests below indicate that a multiplier of 2 significantly improves
+ * performance, and although larger values also provide improvements,
+ * the gains are marginal.
+ *
+ * Therefore, choosing 2 as the multiplier strikes a good balance between
+ * enhancing parallel processing capabilities and maintaining efficient
+ * resource management.
+ *
+ * +------------+-------+-------+-------+-------+-------+
+ * | multiplier | 1 | 2 | 3 | 4 | 5 |
+ * +------------+-------+-------+-------+-------+-------+
+ * | 256G 2node | 358ms | 215ms | 157ms | 134ms | 126ms |
+ * | 2T 4node | 979ms | 679ms | 543ms | 489ms | 481ms |
+ * | 50G 2node | 71ms | 44ms | 37ms | 30ms | 31ms |
+ * +------------+-------+-------+-------+-------+-------+
+ */
+ job.max_threads = num_node_state(N_MEMORY) * 2;
+ job.min_chunk = h->max_huge_pages / num_node_state(N_MEMORY) / 2;
+ padata_do_multithreaded(&job);
+
+ return h->nr_huge_pages;
+}
+
/*
* NOTE: this routine is called in different contexts for gigantic and
* non-gigantic pages.
@@ -3495,11 +3624,8 @@ static void __init hugetlb_hstate_alloc_pages_onenode(struct hstate *h, int nid)
*/
static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
{
- unsigned long i;
- struct folio *folio;
- LIST_HEAD(folio_list);
- nodemask_t *node_alloc_noretry;
- bool node_specific_alloc = false;
+ unsigned long allocated;
+ static bool initialized __initdata;
/* skip gigantic hugepages allocation if hugetlb_cma enabled */
if (hstate_is_gigantic(h) && hugetlb_cma_size) {
@@ -3507,66 +3633,26 @@ static void __init hugetlb_hstate_alloc_pages(struct hstate *h)
return;
}
- /* do node specific alloc */
- for_each_online_node(i) {
- if (h->max_huge_pages_node[i] > 0) {
- hugetlb_hstate_alloc_pages_onenode(h, i);
- node_specific_alloc = true;
- }
+ /* hugetlb_hstate_alloc_pages will be called many times, initialize huge_boot_pages once */
+ if (!initialized) {
+ int i = 0;
+
+ for (i = 0; i < MAX_NUMNODES; i++)
+ INIT_LIST_HEAD(&huge_boot_pages[i]);
+ initialized = true;
}
- if (node_specific_alloc)
+ /* do node specific alloc */
+ if (hugetlb_hstate_alloc_pages_specific_nodes(h))
return;
/* below will do all node balanced alloc */
- if (!hstate_is_gigantic(h)) {
- /*
- * Bit mask controlling how hard we retry per-node allocations.
- * Ignore errors as lower level routines can deal with
- * node_alloc_noretry == NULL. If this kmalloc fails at boot
- * time, we are likely in bigger trouble.
- */
- node_alloc_noretry = kmalloc(sizeof(*node_alloc_noretry),
- GFP_KERNEL);
- } else {
- /* allocations done at boot time */
- node_alloc_noretry = NULL;
- }
-
- /* bit mask controlling how hard we retry per-node allocations */
- if (node_alloc_noretry)
- nodes_clear(*node_alloc_noretry);
-
- for (i = 0; i < h->max_huge_pages; ++i) {
- if (hstate_is_gigantic(h)) {
- /*
- * gigantic pages not added to list as they are not
- * added to pools now.
- */
- if (!alloc_bootmem_huge_page(h, NUMA_NO_NODE))
- break;
- } else {
- folio = alloc_pool_huge_folio(h, &node_states[N_MEMORY],
- node_alloc_noretry);
- if (!folio)
- break;
- list_add(&folio->lru, &folio_list);
- }
- cond_resched();
- }
-
- /* list will be empty if hstate_is_gigantic */
- prep_and_add_allocated_folios(h, &folio_list);
-
- if (i < h->max_huge_pages) {
- char buf[32];
+ if (hstate_is_gigantic(h))
+ allocated = hugetlb_gigantic_pages_alloc_boot(h);
+ else
+ allocated = hugetlb_pages_alloc_boot(h);
- string_get_size(huge_page_size(h), 1, STRING_UNITS_2, buf, 32);
- pr_warn("HugeTLB: allocating %lu of page size %s failed. Only allocated %lu hugepages.\n",
- h->max_huge_pages, buf, i);
- h->max_huge_pages = i;
- }
- kfree(node_alloc_noretry);
+ hugetlb_hstate_alloc_pages_errcheck(allocated, h);
}
static void __init hugetlb_init_hstates(void)
@@ -3668,7 +3754,7 @@ static int adjust_pool_surplus(struct hstate *h, nodemask_t *nodes_allowed,
VM_BUG_ON(delta != -1 && delta != 1);
if (delta < 0) {
- for_each_node_mask_to_alloc(h, nr_nodes, node, nodes_allowed) {
+ for_each_node_mask_to_alloc(&h->next_nid_to_alloc, nr_nodes, node, nodes_allowed) {
if (h->surplus_huge_pages_node[node])
goto found;
}
@@ -3783,7 +3869,8 @@ static int set_max_huge_pages(struct hstate *h, unsigned long count, int nid,
cond_resched();
folio = alloc_pool_huge_folio(h, nodes_allowed,
- node_alloc_noretry);
+ node_alloc_noretry,
+ &h->next_nid_to_alloc);
if (!folio) {
prep_and_add_allocated_folios(h, &page_list);
spin_lock_irq(&hugetlb_lock);
@@ -5585,6 +5672,7 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
struct page *page;
struct hstate *h = hstate_vma(vma);
unsigned long sz = huge_page_size(h);
+ bool adjust_reservation = false;
unsigned long last_addr_mask;
bool force_flush = false;
@@ -5677,7 +5765,31 @@ void __unmap_hugepage_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
hugetlb_count_sub(pages_per_huge_page(h), mm);
hugetlb_remove_rmap(page_folio(page));
+ /*
+ * Restore the reservation for anonymous page, otherwise the
+ * backing page could be stolen by someone.
+ * If there we are freeing a surplus, do not set the restore
+ * reservation bit.
+ */
+ if (!h->surplus_huge_pages && __vma_private_lock(vma) &&
+ folio_test_anon(page_folio(page))) {
+ folio_set_hugetlb_restore_reserve(page_folio(page));
+ /* Reservation to be adjusted after the spin lock */
+ adjust_reservation = true;
+ }
+
spin_unlock(ptl);
+
+ /*
+ * Adjust the reservation for the region that will have the
+ * reserve restored. Keep in mind that vma_needs_reservation() changes
+ * resv->adds_in_progress if it succeeds. If this is not done,
+ * do_exit() will not see it, and will keep the reservation
+ * forever.
+ */
+ if (adjust_reservation && vma_needs_reservation(h, vma, address))
+ vma_add_reservation(h, vma, address);
+
tlb_remove_page_size(tlb, page, huge_page_size(h));
/*
* Bail out after unmapping reference page if supplied
@@ -5826,7 +5938,8 @@ static void unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma,
*/
static vm_fault_t hugetlb_wp(struct mm_struct *mm, struct vm_area_struct *vma,
unsigned long address, pte_t *ptep, unsigned int flags,
- struct folio *pagecache_folio, spinlock_t *ptl)
+ struct folio *pagecache_folio, spinlock_t *ptl,
+ struct vm_fault *vmf)
{
const bool unshare = flags & FAULT_FLAG_UNSHARE;
pte_t pte = huge_ptep_get(ptep);
@@ -5960,10 +6073,9 @@ retry_avoidcopy:
* When the original hugepage is shared one, it does not have
* anon_vma prepared.
*/
- if (unlikely(anon_vma_prepare(vma))) {
- ret = VM_FAULT_OOM;
+ ret = vmf_anon_prepare(vmf);
+ if (unlikely(ret))
goto out_release_all;
- }
if (copy_user_large_folio(new_folio, old_folio, address, vma)) {
ret = VM_FAULT_HWPOISON_LARGE;
@@ -6060,39 +6172,21 @@ int hugetlb_add_to_page_cache(struct folio *folio, struct address_space *mapping
return 0;
}
-static inline vm_fault_t hugetlb_handle_userfault(struct vm_area_struct *vma,
+static inline vm_fault_t hugetlb_handle_userfault(struct vm_fault *vmf,
struct address_space *mapping,
- pgoff_t idx,
- unsigned int flags,
- unsigned long haddr,
- unsigned long addr,
unsigned long reason)
{
u32 hash;
- struct vm_fault vmf = {
- .vma = vma,
- .address = haddr,
- .real_address = addr,
- .flags = flags,
-
- /*
- * Hard to debug if it ends up being
- * used by a callee that assumes
- * something about the other
- * uninitialized fields... same as in
- * memory.c
- */
- };
/*
* vma_lock and hugetlb_fault_mutex must be dropped before handling
* userfault. Also mmap_lock could be dropped due to handling
* userfault, any vma operation should be careful from here.
*/
- hugetlb_vma_unlock_read(vma);
- hash = hugetlb_fault_mutex_hash(mapping, idx);
+ hugetlb_vma_unlock_read(vmf->vma);
+ hash = hugetlb_fault_mutex_hash(mapping, vmf->pgoff);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
- return handle_userfault(&vmf, reason);
+ return handle_userfault(vmf, reason);
}
/*
@@ -6116,7 +6210,8 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
struct vm_area_struct *vma,
struct address_space *mapping, pgoff_t idx,
unsigned long address, pte_t *ptep,
- pte_t old_pte, unsigned int flags)
+ pte_t old_pte, unsigned int flags,
+ struct vm_fault *vmf)
{
struct hstate *h = hstate_vma(vma);
vm_fault_t ret = VM_FAULT_SIGBUS;
@@ -6175,8 +6270,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
goto out;
}
- return hugetlb_handle_userfault(vma, mapping, idx, flags,
- haddr, address,
+ return hugetlb_handle_userfault(vmf, mapping,
VM_UFFD_MISSING);
}
@@ -6221,10 +6315,10 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
new_pagecache_folio = true;
} else {
folio_lock(folio);
- if (unlikely(anon_vma_prepare(vma))) {
- ret = VM_FAULT_OOM;
+
+ ret = vmf_anon_prepare(vmf);
+ if (unlikely(ret))
goto backout_unlocked;
- }
anon_rmap = 1;
}
} else {
@@ -6248,8 +6342,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
ret = 0;
goto out;
}
- return hugetlb_handle_userfault(vma, mapping, idx, flags,
- haddr, address,
+ return hugetlb_handle_userfault(vmf, mapping,
VM_UFFD_MINOR);
}
}
@@ -6292,7 +6385,7 @@ static vm_fault_t hugetlb_no_page(struct mm_struct *mm,
hugetlb_count_add(pages_per_huge_page(h), mm);
if ((flags & FAULT_FLAG_WRITE) && !(vma->vm_flags & VM_SHARED)) {
/* Optimization, do the COW without a second fault */
- ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl);
+ ret = hugetlb_wp(mm, vma, address, ptep, flags, folio, ptl, vmf);
}
spin_unlock(ptl);
@@ -6353,19 +6446,25 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
spinlock_t *ptl;
vm_fault_t ret;
u32 hash;
- pgoff_t idx;
struct folio *folio = NULL;
struct folio *pagecache_folio = NULL;
struct hstate *h = hstate_vma(vma);
struct address_space *mapping;
int need_wait_lock = 0;
unsigned long haddr = address & huge_page_mask(h);
+ struct vm_fault vmf = {
+ .vma = vma,
+ .address = haddr,
+ .real_address = address,
+ .flags = flags,
+ .pgoff = vma_hugecache_offset(h, vma, haddr),
+ /* TODO: Track hugetlb faults using vm_fault */
- /* TODO: Handle faults under the VMA lock */
- if (flags & FAULT_FLAG_VMA_LOCK) {
- vma_end_read(vma);
- return VM_FAULT_RETRY;
- }
+ /*
+ * Some fields may not be initialized, be careful as it may
+ * be hard to debug if called functions make assumptions
+ */
+ };
/*
* Serialize hugepage allocation and instantiation, so that we don't
@@ -6373,8 +6472,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* the same page in the page cache.
*/
mapping = vma->vm_file->f_mapping;
- idx = vma_hugecache_offset(h, vma, haddr);
- hash = hugetlb_fault_mutex_hash(mapping, idx);
+ hash = hugetlb_fault_mutex_hash(mapping, vmf.pgoff);
mutex_lock(&hugetlb_fault_mutex_table[hash]);
/*
@@ -6408,8 +6506,8 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
* hugetlb_no_page will drop vma lock and hugetlb fault
* mutex internally, which make us return immediately.
*/
- return hugetlb_no_page(mm, vma, mapping, idx, address, ptep,
- entry, flags);
+ return hugetlb_no_page(mm, vma, mapping, vmf.pgoff, address,
+ ptep, entry, flags, &vmf);
}
ret = 0;
@@ -6455,7 +6553,8 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
/* Just decrements count, does not deallocate */
vma_end_reservation(h, vma, haddr);
- pagecache_folio = filemap_lock_hugetlb_folio(h, mapping, idx);
+ pagecache_folio = filemap_lock_hugetlb_folio(h, mapping,
+ vmf.pgoff);
if (IS_ERR(pagecache_folio))
pagecache_folio = NULL;
}
@@ -6470,13 +6569,6 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
if (userfaultfd_wp(vma) && huge_pte_uffd_wp(huge_ptep_get(ptep)) &&
(flags & FAULT_FLAG_WRITE) && !huge_pte_write(entry)) {
if (!userfaultfd_wp_async(vma)) {
- struct vm_fault vmf = {
- .vma = vma,
- .address = haddr,
- .real_address = address,
- .flags = flags,
- };
-
spin_unlock(ptl);
if (pagecache_folio) {
folio_unlock(pagecache_folio);
@@ -6510,7 +6602,7 @@ vm_fault_t hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
if (flags & (FAULT_FLAG_WRITE|FAULT_FLAG_UNSHARE)) {
if (!huge_pte_write(entry)) {
ret = hugetlb_wp(mm, vma, address, ptep, flags,
- pagecache_folio, ptl);
+ pagecache_folio, ptl, &vmf);
goto out_put_page;
} else if (likely(flags & FAULT_FLAG_WRITE)) {
entry = huge_pte_mkdirty(entry);
@@ -6688,11 +6780,20 @@ int hugetlb_mfill_atomic_pte(pte_t *dst_pte,
}
/*
- * The memory barrier inside __folio_mark_uptodate makes sure that
- * preceding stores to the page contents become visible before
- * the set_pte_at() write.
+ * If we just allocated a new page, we need a memory barrier to ensure
+ * that preceding stores to the page become visible before the
+ * set_pte_at() write. The memory barrier inside __folio_mark_uptodate
+ * is what we need.
+ *
+ * In the case where we have not allocated a new page (is_continue),
+ * the page must already be uptodate. UFFDIO_CONTINUE already includes
+ * an earlier smp_wmb() to ensure that prior stores will be visible
+ * before the set_pte_at() write.
*/
- __folio_mark_uptodate(folio);
+ if (!is_continue)
+ __folio_mark_uptodate(folio);
+ else
+ WARN_ON_ONCE(!folio_test_uptodate(folio));
/* Add shared, newly allocated pages to the page cache. */
if (vm_shared && !is_continue) {
@@ -7695,6 +7796,13 @@ void __init hugetlb_cma_reserve(int order)
bool node_specific_cma_alloc = false;
int nid;
+ /*
+ * HugeTLB CMA reservation is required for gigantic
+ * huge pages which could not be allocated via the
+ * page allocator. Just warn if there is any change
+ * breaking this assumption.
+ */
+ VM_WARN_ON(order <= MAX_PAGE_ORDER);
cma_reserve_called = true;
if (!hugetlb_cma_size)