From 34ff636f322c6d5e4f0a52338fa63a7dff09a495 Mon Sep 17 00:00:00 2001 From: Joel Fernandes Date: Sat, 18 Jul 2026 13:15:36 -0400 Subject: scftorture: Count single_rpc offline failures in statistics output scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes Signed-off-by: Paul E. McKenney --- fs/proc/page.c | 299 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 299 insertions(+) create mode 100644 fs/proc/page.c (limited to 'fs/proc/page.c') diff --git a/fs/proc/page.c b/fs/proc/page.c new file mode 100644 index 000000000..7d9387143 --- /dev/null +++ b/fs/proc/page.c @@ -0,0 +1,299 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "internal.h" + +#define KPMSIZE sizeof(u64) +#define KPMMASK (KPMSIZE - 1) + +enum kpage_operation { + KPAGE_FLAGS, + KPAGE_COUNT, + KPAGE_CGROUP, +}; + +static inline unsigned long get_max_dump_pfn(void) +{ +#ifdef CONFIG_SPARSEMEM + /* + * The memmap of early sections is completely populated and marked + * online even if max_pfn does not fall on a section boundary - + * pfn_to_online_page() will succeed on all pages. Allow inspecting + * these memmaps. + */ + return round_up(max_pfn, PAGES_PER_SECTION); +#else + return max_pfn; +#endif +} + +static u64 get_kpage_count(const struct page *page) +{ + struct page_snapshot ps; + u64 ret; + + snapshot_page(&ps, page); + + if (IS_ENABLED(CONFIG_PAGE_MAPCOUNT)) + ret = folio_precise_page_mapcount(&ps.folio_snapshot, + &ps.page_snapshot); + else + ret = folio_average_page_mapcount(&ps.folio_snapshot); + + return ret; +} + +static ssize_t kpage_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos, + enum kpage_operation op) +{ + const unsigned long max_dump_pfn = get_max_dump_pfn(); + u64 __user *out = (u64 __user *)buf; + struct page *page; + unsigned long src = *ppos; + unsigned long pfn; + ssize_t ret = 0; + u64 info; + + pfn = src / KPMSIZE; + if (src & KPMMASK || count & KPMMASK) + return -EINVAL; + if (src >= max_dump_pfn * KPMSIZE) + return 0; + count = min_t(unsigned long, count, (max_dump_pfn * KPMSIZE) - src); + + while (count > 0) { + /* + * TODO: ZONE_DEVICE support requires to identify + * memmaps that were actually initialized. + */ + page = pfn_to_online_page(pfn); + + if (page) { + switch (op) { + case KPAGE_FLAGS: + info = stable_page_flags(page); + break; + case KPAGE_COUNT: + info = get_kpage_count(page); + break; + case KPAGE_CGROUP: + info = page_cgroup_ino(page); + break; + default: + info = 0; + break; + } + } else + info = 0; + + if (put_user(info, out)) { + ret = -EFAULT; + break; + } + + pfn++; + out++; + count -= KPMSIZE; + + cond_resched(); + } + + *ppos += (char __user *)out - buf; + if (!ret) + ret = (char __user *)out - buf; + return ret; +} + +/* /proc/kpagecount - an array exposing page mapcounts + * + * Each entry is a u64 representing the corresponding + * physical page mapcount. + */ +static ssize_t kpagecount_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + return kpage_read(file, buf, count, ppos, KPAGE_COUNT); +} + +static const struct proc_ops kpagecount_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_lseek = mem_lseek, + .proc_read = kpagecount_read, +}; + + +static inline u64 kpf_copy_bit(u64 kflags, int ubit, int kbit) +{ + return ((kflags >> kbit) & 1) << ubit; +} + +u64 stable_page_flags(const struct page *page) +{ + const struct folio *folio; + struct page_snapshot ps; + unsigned long k; + unsigned long mapping; + bool is_anon; + u64 u = 0; + + /* + * pseudo flag: KPF_NOPAGE + * it differentiates a memory hole from a page with no flags + */ + if (!page) + return 1 << KPF_NOPAGE; + + snapshot_page(&ps, page); + folio = &ps.folio_snapshot; + + k = folio->flags.f; + mapping = (unsigned long)folio->mapping; + is_anon = mapping & FOLIO_MAPPING_ANON; + + /* + * pseudo flags for the well known (anonymous) memory mapped pages + */ + if (folio_mapped(folio)) + u |= 1 << KPF_MMAP; + if (is_anon) { + u |= 1 << KPF_ANON; + if ((mapping & FOLIO_MAPPING_FLAGS) == FOLIO_MAPPING_KSM) + u |= 1 << KPF_KSM; + } + + /* + * compound pages: export both head/tail info + * they together define a compound page's start/end pos and order + */ + if (ps.idx == 0) + u |= kpf_copy_bit(k, KPF_COMPOUND_HEAD, PG_head); + else + u |= 1 << KPF_COMPOUND_TAIL; + if (folio_test_hugetlb(folio)) + u |= 1 << KPF_HUGE; + else if (folio_test_large(folio) && + folio_test_large_rmappable(folio)) { + /* Note: we indicate any THPs here, not just PMD-sized ones */ + u |= 1 << KPF_THP; + } else if (is_huge_zero_pfn(ps.pfn)) { + u |= 1 << KPF_ZERO_PAGE; + u |= 1 << KPF_THP; + } else if (is_zero_pfn(ps.pfn)) { + u |= 1 << KPF_ZERO_PAGE; + } + + if (ps.flags & PAGE_SNAPSHOT_PG_BUDDY) + u |= 1 << KPF_BUDDY; + + if (folio_test_offline(folio)) + u |= 1 << KPF_OFFLINE; + if (folio_test_pgtable(folio)) + u |= 1 << KPF_PGTABLE; + if (folio_test_slab(folio)) + u |= 1 << KPF_SLAB; + +#if defined(CONFIG_PAGE_IDLE_FLAG) && defined(CONFIG_64BIT) + u |= kpf_copy_bit(k, KPF_IDLE, PG_idle); +#else + if (ps.flags & PAGE_SNAPSHOT_PG_IDLE) + u |= 1 << KPF_IDLE; +#endif + + u |= kpf_copy_bit(k, KPF_LOCKED, PG_locked); + u |= kpf_copy_bit(k, KPF_DIRTY, PG_dirty); + u |= kpf_copy_bit(k, KPF_UPTODATE, PG_uptodate); + u |= kpf_copy_bit(k, KPF_WRITEBACK, PG_writeback); + + u |= kpf_copy_bit(k, KPF_LRU, PG_lru); + u |= kpf_copy_bit(k, KPF_REFERENCED, PG_referenced); + u |= kpf_copy_bit(k, KPF_ACTIVE, PG_active); + u |= kpf_copy_bit(k, KPF_RECLAIM, PG_reclaim); + +#define SWAPCACHE ((1 << PG_swapbacked) | (1 << PG_swapcache)) + if ((k & SWAPCACHE) == SWAPCACHE) + u |= 1 << KPF_SWAPCACHE; + u |= kpf_copy_bit(k, KPF_SWAPBACKED, PG_swapbacked); + + u |= kpf_copy_bit(k, KPF_UNEVICTABLE, PG_unevictable); + u |= kpf_copy_bit(k, KPF_MLOCKED, PG_mlocked); + +#ifdef CONFIG_MEMORY_FAILURE + if (u & (1 << KPF_HUGE)) + u |= kpf_copy_bit(k, KPF_HWPOISON, PG_hwpoison); + else + u |= kpf_copy_bit(ps.page_snapshot.flags.f, KPF_HWPOISON, PG_hwpoison); +#endif + + u |= kpf_copy_bit(k, KPF_RESERVED, PG_reserved); + u |= kpf_copy_bit(k, KPF_OWNER_2, PG_owner_2); + u |= kpf_copy_bit(k, KPF_PRIVATE, PG_private); + u |= kpf_copy_bit(k, KPF_PRIVATE_2, PG_private_2); + u |= kpf_copy_bit(k, KPF_OWNER_PRIVATE, PG_owner_priv_1); + u |= kpf_copy_bit(k, KPF_ARCH, PG_arch_1); +#ifdef CONFIG_ARCH_USES_PG_ARCH_2 + u |= kpf_copy_bit(k, KPF_ARCH_2, PG_arch_2); +#endif +#ifdef CONFIG_ARCH_USES_PG_ARCH_3 + u |= kpf_copy_bit(k, KPF_ARCH_3, PG_arch_3); +#endif + + return u; +} +EXPORT_SYMBOL_GPL(stable_page_flags); + +/* /proc/kpageflags - an array exposing page flags + * + * Each entry is a u64 representing the corresponding + * physical page flags. + */ +static ssize_t kpageflags_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + return kpage_read(file, buf, count, ppos, KPAGE_FLAGS); +} + +static const struct proc_ops kpageflags_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_lseek = mem_lseek, + .proc_read = kpageflags_read, +}; + +#ifdef CONFIG_MEMCG +static ssize_t kpagecgroup_read(struct file *file, char __user *buf, + size_t count, loff_t *ppos) +{ + return kpage_read(file, buf, count, ppos, KPAGE_CGROUP); +} +static const struct proc_ops kpagecgroup_proc_ops = { + .proc_flags = PROC_ENTRY_PERMANENT, + .proc_lseek = mem_lseek, + .proc_read = kpagecgroup_read, +}; +#endif /* CONFIG_MEMCG */ + +static int __init proc_page_init(void) +{ + proc_create("kpagecount", S_IRUSR, NULL, &kpagecount_proc_ops); + proc_create("kpageflags", S_IRUSR, NULL, &kpageflags_proc_ops); +#ifdef CONFIG_MEMCG + proc_create("kpagecgroup", S_IRUSR, NULL, &kpagecgroup_proc_ops); +#endif + return 0; +} +fs_initcall(proc_page_init); -- cgit v1.3.1