mm: convert totalram_pages and totalhigh_pages variables to atomic

totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things. It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[[e-mail]: coding style fixes]
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arun KS <[e-mail]>
Suggested-by: Michal Hocko <[e-mail]>
Suggested-by: Vlastimil Babka <[e-mail]>
Reviewed-by: Konstantin Khlebnikov <[e-mail]>
Reviewed-by: Pavel Tatashin <[e-mail]>
Acked-by: Michal Hocko <[e-mail]>
Acked-by: Vlastimil Babka <[e-mail]>
Cc: David Hildenbrand <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

arch/csky/mm/init.c

···
 		ClearPageReserved(virt_to_page(start));
 		init_page_count(virt_to_page(start));
 		free_page(start);
-		totalram_pages++;
+		totalram_pages_inc();
 	}
 }
 #endif
···
 		ClearPageReserved(virt_to_page(addr));
 		init_page_count(virt_to_page(addr));
 		free_page(addr);
-		totalram_pages++;
+		totalram_pages_inc();
 		addr += PAGE_SIZE;
 	}
 

arch/powerpc/platforms/pseries/cmm.c

···
 
 		pa->page[pa->index++] = addr;
 		loaned_pages++;
-		totalram_pages--;
+		totalram_pages_dec();
 		spin_unlock(&cmm_lock);
 		nr--;
 	}
···
 		free_page(addr);
 		loaned_pages--;
 		nr--;
-		totalram_pages++;
+		totalram_pages_inc();
 	}
 	spin_unlock(&cmm_lock);
 	cmm_dbg("End request with %ld pages unfulfilled\n", nr);
···
 	int rc;
 	struct hvcall_mpp_data mpp_data;
 	signed long active_pages_target, page_loan_request, target;
-	signed long total_pages = totalram_pages + loaned_pages;
+	signed long total_pages = totalram_pages() + loaned_pages;
 	signed long min_mem_pages = (min_mem_mb * 1024 * 1024) / PAGE_SIZE;
 
 	rc = h_get_mpp(&mpp_data);
···
 
 	cmm_dbg("delta = %ld, loaned = %lu, target = %lu, oom = %lu, totalram = %lu\n",
 		page_loan_request, loaned_pages, loaned_pages_target,
-		oom_freed_pages, totalram_pages);
+		oom_freed_pages, totalram_pages());
 }
 
 static struct notifier_block cmm_oom_nb = {
···
 			free_page(pa_curr->page[idx]);
 			freed++;
 			loaned_pages--;
-			totalram_pages++;
+			totalram_pages_inc();
 			pa_curr->page[idx] = pa_last->page[--pa_last->index];
 			if (pa_last->index == 0) {
 				if (pa_curr == pa_last)

arch/s390/mm/init.c

···
 	order = 7;
 
 	/* Limit number of empty zero pages for small memory sizes */
-	while (order > 2 && (totalram_pages >> 10) < (1UL << order))
+	while (order > 2 && (totalram_pages() >> 10) < (1UL << order))
 		order--;
 
 	empty_zero_page = __get_free_pages(GFP_KERNEL | __GFP_ZERO, order);

arch/um/kernel/mem.c

···
 
 	/* this will put all low memory onto the freelists */
 	memblock_free_all();
-	max_low_pfn = totalram_pages;
+	max_low_pfn = totalram_pages();
 	max_pfn = max_low_pfn;
 	mem_init_print_info(NULL);
 	kmalloc_ok = 1;

arch/x86/kernel/cpu/microcode/core.c

···
 			       size_t len, loff_t *ppos)
 {
 	ssize_t ret = -EINVAL;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 
 	if ((len >> PAGE_SHIFT) > nr_pages) {
 		pr_err("too much data (max %ld pages)\n", nr_pages);

drivers/char/agp/backend.c

···
 	long memory, index, result;
 
 #if PAGE_SHIFT < 20
-	memory = totalram_pages >> (20 - PAGE_SHIFT);
+	memory = totalram_pages() >> (20 - PAGE_SHIFT);
 #else
-	memory = totalram_pages << (PAGE_SHIFT - 20);
+	memory = totalram_pages() << (PAGE_SHIFT - 20);
 #endif
 	index = 1;
 

drivers/gpu/drm/i915/i915_gem.c

···
 	 * If there's no chance of allocating enough pages for the whole
 	 * object, bail early.
 	 */
-	if (page_count > totalram_pages)
+	if (page_count > totalram_pages())
 		return -ENOMEM;
 
 	st = kmalloc(sizeof(*st), GFP_KERNEL);

drivers/gpu/drm/i915/selftests/i915_gem_gtt.c

···
 	 * This should ensure that we do not run into the oomkiller during
 	 * the test and take down the machine wilfully.
 	 */
-	limit = totalram_pages << PAGE_SHIFT;
+	limit = totalram_pages() << PAGE_SHIFT;
 	limit = min(ppgtt->vm.total, limit);
 
 	/* Check we can allocate the entire range */
···
 				     u64 hole_start, u64 hole_end,
 				     unsigned long end_time))
 {
-	const u64 limit = totalram_pages << PAGE_SHIFT;
+	const u64 limit = totalram_pages() << PAGE_SHIFT;
 	struct i915_gem_context *ctx;
 	struct i915_hw_ppgtt *ppgtt;
 	IGT_TIMEOUT(end_time);

drivers/hv/hv_balloon.c

···
 static unsigned long compute_balloon_floor(void)
 {
 	unsigned long min_pages;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 #define MB2PAGES(mb) ((mb) << (20 - PAGE_SHIFT))
 	/* Simple continuous piecewiese linear function:
 	 *  max MiB -> min MiB  gradient

drivers/md/dm-bufio.c

···
 	dm_bufio_allocated_vmalloc = 0;
 	dm_bufio_current_allocated = 0;
 
-	mem = (__u64)mult_frac(totalram_pages - totalhigh_pages,
+	mem = (__u64)mult_frac(totalram_pages() - totalhigh_pages(),
 			       DM_BUFIO_MEMORY_PERCENT, 100) << PAGE_SHIFT;
 
 	if (mem > ULONG_MAX)

drivers/md/dm-crypt.c

···
 
 static void crypt_calculate_pages_per_client(void)
 {
-	unsigned long pages = (totalram_pages - totalhigh_pages) * DM_CRYPT_MEMORY_PERCENT / 100;
+	unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
 
 	if (!dm_crypt_clients_n)
 		return;

drivers/md/dm-integrity.c

···
 	journal_pages = roundup((__u64)ic->journal_sections * ic->journal_section_sectors,
 				PAGE_SIZE >> SECTOR_SHIFT) >> (PAGE_SHIFT - SECTOR_SHIFT);
 	journal_desc_size = journal_pages * sizeof(struct page_list);
-	if (journal_pages >= totalram_pages - totalhigh_pages || journal_desc_size > ULONG_MAX) {
+	if (journal_pages >= totalram_pages() - totalhigh_pages() || journal_desc_size > ULONG_MAX) {
 		*error = "Journal doesn't fit into memory";
 		r = -ENOMEM;
 		goto bad;

drivers/md/dm-stats.c

···
 	a = shared_memory_amount + alloc_size;
 	if (a < shared_memory_amount)
 		return false;
-	if (a >> PAGE_SHIFT > totalram_pages / DM_STATS_MEMORY_FACTOR)
+	if (a >> PAGE_SHIFT > totalram_pages() / DM_STATS_MEMORY_FACTOR)
 		return false;
 #ifdef CONFIG_MMU
 	if (a > (VMALLOC_END - VMALLOC_START) / DM_STATS_VMALLOC_FACTOR)

drivers/media/platform/mtk-vpu/mtk_vpu.c

···
 	/* Set PTCM to 96K and DTCM to 32K */
 	vpu_cfg_writel(vpu, 0x2, VPU_TCM_CFG);
 
-	vpu->enable_4GB = !!(totalram_pages > (SZ_2G >> PAGE_SHIFT));
+	vpu->enable_4GB = !!(totalram_pages() > (SZ_2G >> PAGE_SHIFT));
 	dev_info(dev, "4GB mode %u\n", vpu->enable_4GB);
 
 	if (vpu->enable_4GB) {

drivers/misc/vmw_balloon.c

···
 	unsigned long status;
 	unsigned long limit;
 
-	limit = totalram_pages;
+	limit = totalram_pages();
 
 	/* Ensure limit fits in 32-bits */
 	if (limit != (u32)limit)

drivers/parisc/ccio-dma.c

···
 	** Hot-Plug/Removal of PCI cards. (aka PCI OLARD).
 	*/
 
-	iova_space_size = (u32) (totalram_pages / count_parisc_driver(&ccio_driver));
+	iova_space_size = (u32) (totalram_pages() / count_parisc_driver(&ccio_driver));
 
 	/* limit IOVA space size to 1MB-1GB */
 
···
 
 	DBG_INIT("%s() hpa 0x%p mem %luMB IOV %dMB (%d bits)\n",
 			__func__, ioc->ioc_regs,
-			(unsigned long) totalram_pages >> (20 - PAGE_SHIFT),
+			(unsigned long) totalram_pages() >> (20 - PAGE_SHIFT),
 			iova_space_size>>20,
 			iov_order + PAGE_SHIFT);
 

drivers/parisc/sba_iommu.c

···
 	** for DMA hints - ergo only 30 bits max.
 	*/
 
-	iova_space_size = (u32) (totalram_pages/global_ioc_cnt);
+	iova_space_size = (u32) (totalram_pages()/global_ioc_cnt);
 
 	/* limit IOVA space size to 1MB-1GB */
 	if (iova_space_size < (1 << (20 - PAGE_SHIFT))) {
···
 	DBG_INIT("%s() hpa 0x%lx mem %ldMB IOV %dMB (%d bits)\n",
 			__func__,
 			ioc->ioc_hpa,
-			(unsigned long) totalram_pages >> (20 - PAGE_SHIFT),
+			(unsigned long) totalram_pages() >> (20 - PAGE_SHIFT),
 			iova_space_size>>20,
 			iov_order + PAGE_SHIFT);
 

drivers/staging/android/ion/ion_system_heap.c

···
 	unsigned long size_remaining = PAGE_ALIGN(size);
 	unsigned int max_order = orders[0];
 
-	if (size / PAGE_SIZE > totalram_pages / 2)
+	if (size / PAGE_SIZE > totalram_pages() / 2)
 		return -ENOMEM;
 
 	INIT_LIST_HEAD(&pages);

drivers/xen/xen-selfballoon.c

···
 	bool reset_timer = false;
 
 	if (xen_selfballooning_enabled) {
-		cur_pages = totalram_pages;
+		cur_pages = totalram_pages();
 		tgt_pages = cur_pages; /* default is no change */
 		goal_pages = vm_memory_committed() +
 				totalreserve_pages +
···
 		if (tgt_pages < floor_pages)
 			tgt_pages = floor_pages;
 		balloon_set_new_target(tgt_pages +
-			balloon_stats.current_pages - totalram_pages);
+			balloon_stats.current_pages - totalram_pages());
 		reset_timer = true;
 	}
 #ifdef CONFIG_FRONTSWAP
···
 	 * much more reliably and response faster in some cases.
 	 */
 	if (!selfballoon_reserved_mb) {
-		reserve_pages = totalram_pages / 10;
+		reserve_pages = totalram_pages() / 10;
 		selfballoon_reserved_mb = PAGES2MB(reserve_pages);
 	}
 	schedule_delayed_work(&selfballoon_worker, selfballoon_interval * HZ);

fs/ceph/super.h

···
 	 * This allows larger machines to have larger/more transfers.
 	 * Limit the default to 256M
 	 */
-	congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+	congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10);
 	if (congestion_kb > 256*1024)
 		congestion_kb = 256*1024;
 

fs/file_table.c

···
 void __init files_maxfiles_init(void)
 {
 	unsigned long n;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 	unsigned long memreserve = (nr_pages - nr_free_pages()) * 3/2;
 
 	memreserve = min(memreserve, nr_pages - 1);

fs/fuse/inode.c

···
 static void sanitize_global_limit(unsigned *limit)
 {
 	if (*limit == 0)
-		*limit = ((totalram_pages << PAGE_SHIFT) >> 13) /
+		*limit = ((totalram_pages() << PAGE_SHIFT) >> 13) /
 			 sizeof(struct fuse_req);
 
 	if (*limit >= 1 << 16)

fs/nfs/write.c

···
 	 * This allows larger machines to have larger/more transfers.
 	 * Limit the default to 256M
 	 */
-	nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+	nfs_congestion_kb = (16*int_sqrt(totalram_pages())) << (PAGE_SHIFT-10);
 	if (nfs_congestion_kb > 256*1024)
 		nfs_congestion_kb = 256*1024;
 

fs/nfsd/nfscache.c

···
 nfsd_cache_size_limit(void)
 {
 	unsigned int limit;
-	unsigned long low_pages = totalram_pages - totalhigh_pages;
+	unsigned long low_pages = totalram_pages() - totalhigh_pages();
 
 	limit = (16 * int_sqrt(low_pages)) << (PAGE_SHIFT-10);
 	return min_t(unsigned int, limit, 256*1024);

fs/ntfs/malloc.h

···
 		return kmalloc(PAGE_SIZE, gfp_mask & ~__GFP_HIGHMEM);
 		/* return (void *)__get_free_page(gfp_mask); */
 	}
-	if (likely((size >> PAGE_SHIFT) < totalram_pages))
+	if (likely((size >> PAGE_SHIFT) < totalram_pages()))
 		return __vmalloc(size, gfp_mask, PAGE_KERNEL);
 	return NULL;
 }

fs/proc/base.c

···
 static int proc_oom_score(struct seq_file *m, struct pid_namespace *ns,
 			  struct pid *pid, struct task_struct *task)
 {
-	unsigned long totalpages = totalram_pages + total_swap_pages;
+	unsigned long totalpages = totalram_pages() + total_swap_pages;
 	unsigned long points = 0;
 
 	points = oom_badness(task, NULL, NULL, totalpages) *

include/linux/highmem.h

···
 
 /* declarations for linux/mm/highmem.c */
 unsigned int nr_free_highpages(void);
-extern unsigned long totalhigh_pages;
+extern atomic_long_t _totalhigh_pages;
+static inline unsigned long totalhigh_pages(void)
+{
+	return (unsigned long)atomic_long_read(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_inc(void)
+{
+	atomic_long_inc(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_dec(void)
+{
+	atomic_long_dec(&_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_add(long count)
+{
+	atomic_long_add(count, &_totalhigh_pages);
+}
+
+static inline void totalhigh_pages_set(long val)
+{
+	atomic_long_set(&_totalhigh_pages, val);
+}
 
 void kmap_flush_unused(void);
 
···
 	return virt_to_page(addr);
 }
 
-#define totalhigh_pages 0UL
+static inline unsigned long totalhigh_pages(void) { return 0UL; }
 
 #ifndef ARCH_HAS_KMAP
 static inline void *kmap(struct page *page)

include/linux/mm.h

···
 static inline void set_max_mapnr(unsigned long limit) { }
 #endif
 
-extern unsigned long totalram_pages;
+extern atomic_long_t _totalram_pages;
+static inline unsigned long totalram_pages(void)
+{
+	return (unsigned long)atomic_long_read(&_totalram_pages);
+}
+
+static inline void totalram_pages_inc(void)
+{
+	atomic_long_inc(&_totalram_pages);
+}
+
+static inline void totalram_pages_dec(void)
+{
+	atomic_long_dec(&_totalram_pages);
+}
+
+static inline void totalram_pages_add(long count)
+{
+	atomic_long_add(count, &_totalram_pages);
+}
+
+static inline void totalram_pages_set(long val)
+{
+	atomic_long_set(&_totalram_pages, val);
+}
+
 extern void * high_memory;
 extern int page_cluster;
 

include/linux/swap.h

···
 } while (0)
 
 /* linux/mm/page_alloc.c */
-extern unsigned long totalram_pages;
 extern unsigned long totalreserve_pages;
 extern unsigned long nr_free_buffer_pages(void);
 extern unsigned long nr_free_pagecache_pages(void);

kernel/fork.c

···
 static void set_max_threads(unsigned int max_threads_suggested)
 {
 	u64 threads;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 
 	/*
 	 * The number of threads shall be limited such that the thread

kernel/kexec_core.c

···
 	int i;
 	unsigned long nr_segments = image->nr_segments;
 	unsigned long total_pages = 0;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 
 	/*
 	 * Verify we have good destination addresses.  The caller is

kernel/power/snapshot.c

···
 
 void __init hibernate_image_size_init(void)
 {
-	image_size = ((totalram_pages * 2) / 5) * PAGE_SIZE;
+	image_size = ((totalram_pages() * 2) / 5) * PAGE_SIZE;
 }
 
 /*

mm/highmem.c

···
 }
 #endif
 
-unsigned long totalhigh_pages __read_mostly;
-EXPORT_SYMBOL(totalhigh_pages);
-
+atomic_long_t _totalhigh_pages __read_mostly;
+EXPORT_SYMBOL(_totalhigh_pages);
 
 EXPORT_PER_CPU_SYMBOL(__kmap_atomic_idx);
 

mm/huge_memory.c

···
 	 * where the extra memory used could hurt more than TLB overhead
 	 * is likely to save.  The admin can still enable it through /sys.
 	 */
-	if (totalram_pages < (512 << (20 - PAGE_SHIFT))) {
+	if (totalram_pages() < (512 << (20 - PAGE_SHIFT))) {
 		transparent_hugepage_flags = 0;
 		return 0;
 	}

mm/kasan/quarantine.c

···
 	 * Update quarantine size in case of hotplug. Allocate a fraction of
 	 * the installed memory to quarantine minus per-cpu queue limits.
 	 */
-	total_size = (READ_ONCE(totalram_pages) << PAGE_SHIFT) /
+	total_size = (totalram_pages() << PAGE_SHIFT) /
 		QUARANTINE_FRACTION;
 	percpu_quarantines = QUARANTINE_PERCPU_SIZE * num_online_cpus();
 	new_quarantine_size = (total_size < percpu_quarantines) ?

mm/memblock.c

···
 
 	for (; cursor < end; cursor++) {
 		memblock_free_pages(pfn_to_page(cursor), cursor, 0);
-		totalram_pages++;
+		totalram_pages_inc();
 	}
 }
 
···
 	reset_all_zones_managed_pages();
 
 	pages = free_low_memory_core_early();
-	totalram_pages += pages;
+	totalram_pages_add(pages);
 
 	return pages;
 }

mm/mm_init.c

···
 	s32 batch = max_t(s32, nr*2, 32);
 
 	/* batch size set to 0.4% of (total memory/#cpus), or max int32 */
-	memsized_batch = min_t(u64, (totalram_pages/nr)/256, 0x7fffffff);
+	memsized_batch = min_t(u64, (totalram_pages()/nr)/256, 0x7fffffff);
 
 	vm_committed_as_batch = max_t(s32, memsized_batch, batch);
 }

mm/oom_kill.c

···
 	}
 
 	/* Default to all available memory */
-	oc->totalpages = totalram_pages + total_swap_pages;
+	oc->totalpages = totalram_pages() + total_swap_pages;
 
 	if (!IS_ENABLED(CONFIG_NUMA))
 		return CONSTRAINT_NONE;

mm/page_alloc.c

···
 
 #include <linux/stddef.h>
 #include <linux/mm.h>
+#include <linux/highmem.h>
 #include <linux/swap.h>
 #include <linux/interrupt.h>
 #include <linux/pagemap.h>
···
 /* Protect totalram_pages and zone->managed_pages */
 static DEFINE_SPINLOCK(managed_page_count_lock);
 
-unsigned long totalram_pages __read_mostly;
+atomic_long_t _totalram_pages __read_mostly;
+EXPORT_SYMBOL(_totalram_pages);
 unsigned long totalreserve_pages __read_mostly;
 unsigned long totalcma_pages __read_mostly;
 
···
 
 void si_meminfo(struct sysinfo *val)
 {
-	val->totalram = totalram_pages;
+	val->totalram = totalram_pages();
 	val->sharedram = global_node_page_state(NR_SHMEM);
 	val->freeram = global_zone_page_state(NR_FREE_PAGES);
 	val->bufferram = nr_blockdev_pages();
-	val->totalhigh = totalhigh_pages;
+	val->totalhigh = totalhigh_pages();
 	val->freehigh = nr_free_highpages();
 	val->mem_unit = PAGE_SIZE;
 }
···
 {
 	spin_lock(&managed_page_count_lock);
 	atomic_long_add(count, &page_zone(page)->managed_pages);
-	totalram_pages += count;
+	totalram_pages_add(count);
 #ifdef CONFIG_HIGHMEM
 	if (PageHighMem(page))
-		totalhigh_pages += count;
+		totalhigh_pages_add(count);
 #endif
 	spin_unlock(&managed_page_count_lock);
 }
···
 void free_highmem_page(struct page *page)
 {
 	__free_reserved_page(page);
-	totalram_pages++;
+	totalram_pages_inc();
 	atomic_long_inc(&page_zone(page)->managed_pages);
-	totalhigh_pages++;
+	totalhigh_pages_inc();
 }
 #endif
 
···
 		physpages << (PAGE_SHIFT - 10),
 		codesize >> 10, datasize >> 10, rosize >> 10,
 		(init_data_size + init_code_size) >> 10, bss_size >> 10,
-		(physpages - totalram_pages - totalcma_pages) << (PAGE_SHIFT - 10),
+		(physpages - totalram_pages() - totalcma_pages) << (PAGE_SHIFT - 10),
 		totalcma_pages << (PAGE_SHIFT - 10),
 #ifdef	CONFIG_HIGHMEM
-		totalhigh_pages << (PAGE_SHIFT - 10),
+		totalhigh_pages() << (PAGE_SHIFT - 10),
 #endif
 		str ? ", " : "", str ? str : "");
 }

mm/shmem.c

···
 #ifdef CONFIG_TMPFS
 static unsigned long shmem_default_max_blocks(void)
 {
-	return totalram_pages / 2;
+	return totalram_pages() / 2;
 }
 
 static unsigned long shmem_default_max_inodes(void)
 {
-	unsigned long nr_pages = totalram_pages;
-	return min(nr_pages - totalhigh_pages, nr_pages / 2);
+	unsigned long nr_pages = totalram_pages();
+
+	return min(nr_pages - totalhigh_pages(), nr_pages / 2);
 }
 #endif
 
···
 			size = memparse(value,&rest);
 			if (*rest == '%') {
 				size <<= PAGE_SHIFT;
-				size *= totalram_pages;
+				size *= totalram_pages();
 				do_div(size, 100);
 				rest++;
 			}

mm/slab.c

···
 	 * page orders on machines with more than 32MB of memory if
 	 * not overridden on the command line.
 	 */
-	if (!slab_max_order_set && totalram_pages > (32 << 20) >> PAGE_SHIFT)
+	if (!slab_max_order_set && totalram_pages() > (32 << 20) >> PAGE_SHIFT)
 		slab_max_order = SLAB_MAX_ORDER_HI;
 
 	/* Bootstrap is tricky, because several objects are allocated

mm/swap.c

···
  */
 void __init swap_setup(void)
 {
-	unsigned long megs = totalram_pages >> (20 - PAGE_SHIFT);
+	unsigned long megs = totalram_pages() >> (20 - PAGE_SHIFT);
 
 	/* Use a smaller cluster for small-memory machines */
 	if (megs < 16)

mm/util.c

···
 	if (sysctl_overcommit_kbytes)
 		allowed = sysctl_overcommit_kbytes >> (PAGE_SHIFT - 10);
 	else
-		allowed = ((totalram_pages - hugetlb_total_pages())
+		allowed = ((totalram_pages() - hugetlb_total_pages())
 			   * sysctl_overcommit_ratio / 100);
 	allowed += total_swap_pages;
 

mm/vmalloc.c

···
 
 	might_sleep();
 
-	if (count > totalram_pages)
+	if (count > totalram_pages())
 		return NULL;
 
 	size = (unsigned long)count << PAGE_SHIFT;
···
 	unsigned long real_size = size;
 
 	size = PAGE_ALIGN(size);
-	if (!size || (size >> PAGE_SHIFT) > totalram_pages)
+	if (!size || (size >> PAGE_SHIFT) > totalram_pages())
 		goto fail;
 
 	area = __get_vm_area_node(size, align, VM_ALLOC | VM_UNINITIALIZED |

mm/workingset.c

···
 	 * double the initial memory by using totalram_pages as-is.
 	 */
 	timestamp_bits = BITS_PER_LONG - EVICTION_SHIFT;
-	max_order = fls_long(totalram_pages - 1);
+	max_order = fls_long(totalram_pages() - 1);
 	if (max_order > timestamp_bits)
 		bucket_order = max_order - timestamp_bits;
 	pr_info("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",

mm/zswap.c

···
 
 static bool zswap_is_full(void)
 {
-	return totalram_pages * zswap_max_pool_percent / 100 <
-		DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
+	return totalram_pages() * zswap_max_pool_percent / 100 <
+			DIV_ROUND_UP(zswap_pool_total_size, PAGE_SIZE);
 }
 
 static void zswap_update_total_size(void)

net/dccp/proto.c

···
 static int __init dccp_init(void)
 {
 	unsigned long goal;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 	int ehash_order, bhash_order, i;
 	int rc;
 

net/decnet/dn_route.c

···
 	dn_route_timer.expires = jiffies + decnet_dst_gc_interval * HZ;
 	add_timer(&dn_route_timer);
 
-	goal = totalram_pages >> (26 - PAGE_SHIFT);
+	goal = totalram_pages() >> (26 - PAGE_SHIFT);
 
 	for(order = 0; (1UL << order) < goal; order++)
 		/* NOTHING */;

net/ipv4/tcp_metrics.c

···
 
 	slots = tcpmhash_entries;
 	if (!slots) {
-		if (totalram_pages >= 128 * 1024)
+		if (totalram_pages() >= 128 * 1024)
 			slots = 16 * 1024;
 		else
 			slots = 8 * 1024;

net/netfilter/nf_conntrack_core.c

···
 
 int nf_conntrack_init_start(void)
 {
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 	int max_factor = 8;
 	int ret = -ENOMEM;
 	int i;

net/netfilter/xt_hashlimit.c

···
 	struct xt_hashlimit_htable *hinfo;
 	const struct seq_operations *ops;
 	unsigned int size, i;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 	int ret;
 
 	if (cfg->size) {

net/sctp/protocol.c

···
 	int status = -EINVAL;
 	unsigned long goal;
 	unsigned long limit;
-	unsigned long nr_pages = totalram_pages;
+	unsigned long nr_pages = totalram_pages();
 	int max_share;
 	int order;
 	int num_entries;

security/integrity/ima/ima_kexec.c

···
 		kexec_segment_size = ALIGN(ima_get_binary_runtime_size() +
 					   PAGE_SIZE / 2, PAGE_SIZE);
 	if ((kexec_segment_size == ULONG_MAX) ||
-	    ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages / 2)) {
+	    ((kexec_segment_size >> PAGE_SHIFT) > totalram_pages() / 2)) {
 		pr_err("Binary measurement list too large.\n");
 		return;
 	}