From: "Liu, Yujie" <yujie.liu@intel.com>
To: "21cnbao@gmail.com" <21cnbao@gmail.com>, lkp <lkp@intel.com>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
"llvm@lists.linux.dev" <llvm@lists.linux.dev>,
"v-songbaohua@oppo.com" <v-songbaohua@oppo.com>,
"oe-kbuild-all@lists.linux.dev" <oe-kbuild-all@lists.linux.dev>,
"akpm@linux-foundation.org" <akpm@linux-foundation.org>
Subject: Re: [akpm-mm:mm-unstable 364/372] mm/memory.c:4169:3: error: call to undeclared function 'count_mthp_stat'; ISO C99 and later do not support implicit function declarations
Date: Fri, 12 Apr 2024 02:58:36 +0000 [thread overview]
Message-ID: <7093386ea71c1c7c4c8ae68a25818d6582ac8f22.camel@intel.com> (raw)
In-Reply-To: <CAGsJ_4yEa0PJrwQmEEmcjaUAMSWgES7rPjNDh1_WAcnx3pwOwg@mail.gmail.com>
On Thu, 2024-04-11 at 22:07 +1200, Barry Song wrote:
> On Thu, Apr 11, 2024 at 9:50 PM kernel test robot <lkp@intel.com> wrote:
> >
> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-unstable
> > head: de14d5f2a9ff2df737a01575ee95bc5a35f5853d
> > commit: 37a4ecbf36cbc84bb1aff0f9c81e58261f8826d9 [364/372] mm: add per-order mTHP swpin_refault counter
> > config: s390-allnoconfig (https://download.01.org/0day-ci/archive/20240411/202404111716.GLefx4HG-lkp@intel.com/config)
> > compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 8b3b4a92adee40483c27f26c478a384cd69c6f05)
> > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240411/202404111716.GLefx4HG-lkp@intel.com/reproduce)
> >
> > If you fix the issue in a separate patch/commit (i.e. not just a new version of
> > the same patch/commit), kindly add following tags
> > > Reported-by: kernel test robot <lkp@intel.com>
> > > Closes: https://lore.kernel.org/oe-kbuild-all/202404111716.GLefx4HG-lkp@intel.com/
> >
> > All errors (new ones prefixed by >>):
> >
> > > > mm/memory.c:4169:3: error: call to undeclared function 'count_mthp_stat'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
> > 4169 | count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_SWPIN_REFAULT);
> > | ^
> > > > mm/memory.c:4169:39: error: use of undeclared identifier 'MTHP_STAT_ANON_SWPIN_REFAULT'
> > 4169 | count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_SWPIN_REFAULT);
> > | ^
> > 16 warnings and 2 errors generated.
>
> Hi,
> Thanks! SeongJae also reported this issue, and I had a fix here
> https://lore.kernel.org/linux-mm/20240411014636.14023-1-21cnbao@gmail.com/
>
> Can you please test it?
We tested the patch above and confirmed it fixes the build error in
this report.
Tested-by: Yujie Liu <yujie.liu@intel.com>
Thanks
> >
> >
> > vim +/count_mthp_stat +4169 mm/memory.c
> >
> > 3927
> > 3928 /*
> > 3929 * We enter with non-exclusive mmap_lock (to exclude vma changes,
> > 3930 * but allow concurrent faults), and pte mapped but not yet locked.
> > 3931 * We return with pte unmapped and unlocked.
> > 3932 *
> > 3933 * We return with the mmap_lock locked or unlocked in the same cases
> > 3934 * as does filemap_fault().
> > 3935 */
> > 3936 vm_fault_t do_swap_page(struct vm_fault *vmf)
> > 3937 {
> > 3938 struct vm_area_struct *vma = vmf->vma;
> > 3939 struct folio *swapcache, *folio = NULL;
> > 3940 struct page *page;
> > 3941 struct swap_info_struct *si = NULL;
> > 3942 rmap_t rmap_flags = RMAP_NONE;
> > 3943 bool need_clear_cache = false;
> > 3944 bool exclusive = false;
> > 3945 swp_entry_t entry;
> > 3946 pte_t pte;
> > 3947 vm_fault_t ret = 0;
> > 3948 void *shadow = NULL;
> > 3949 int nr_pages = 1;
> > 3950 unsigned long start_address = vmf->address;
> > 3951 pte_t *start_pte = vmf->pte;
> > 3952 bool any_swap_shared = false;
> > 3953
> > 3954 if (!pte_unmap_same(vmf))
> > 3955 goto out;
> > 3956
> > 3957 entry = pte_to_swp_entry(vmf->orig_pte);
> > 3958 if (unlikely(non_swap_entry(entry))) {
> > 3959 if (is_migration_entry(entry)) {
> > 3960 migration_entry_wait(vma->vm_mm, vmf->pmd,
> > 3961 vmf->address);
> > 3962 } else if (is_device_exclusive_entry(entry)) {
> > 3963 vmf->page = pfn_swap_entry_to_page(entry);
> > 3964 ret = remove_device_exclusive_entry(vmf);
> > 3965 } else if (is_device_private_entry(entry)) {
> > 3966 if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
> > 3967 /*
> > 3968 * migrate_to_ram is not yet ready to operate
> > 3969 * under VMA lock.
> > 3970 */
> > 3971 vma_end_read(vma);
> > 3972 ret = VM_FAULT_RETRY;
> > 3973 goto out;
> > 3974 }
> > 3975
> > 3976 vmf->page = pfn_swap_entry_to_page(entry);
> > 3977 vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
> > 3978 vmf->address, &vmf->ptl);
> > 3979 if (unlikely(!vmf->pte ||
> > 3980 !pte_same(ptep_get(vmf->pte),
> > 3981 vmf->orig_pte)))
> > 3982 goto unlock;
> > 3983
> > 3984 /*
> > 3985 * Get a page reference while we know the page can't be
> > 3986 * freed.
> > 3987 */
> > 3988 get_page(vmf->page);
> > 3989 pte_unmap_unlock(vmf->pte, vmf->ptl);
> > 3990 ret = vmf->page->pgmap->ops->migrate_to_ram(vmf);
> > 3991 put_page(vmf->page);
> > 3992 } else if (is_hwpoison_entry(entry)) {
> > 3993 ret = VM_FAULT_HWPOISON;
> > 3994 } else if (is_pte_marker_entry(entry)) {
> > 3995 ret = handle_pte_marker(vmf);
> > 3996 } else {
> > 3997 print_bad_pte(vma, vmf->address, vmf->orig_pte, NULL);
> > 3998 ret = VM_FAULT_SIGBUS;
> > 3999 }
> > 4000 goto out;
> > 4001 }
> > 4002
> > 4003 /* Prevent swapoff from happening to us. */
> > 4004 si = get_swap_device(entry);
> > 4005 if (unlikely(!si))
> > 4006 goto out;
> > 4007
> > 4008 folio = swap_cache_get_folio(entry, vma, vmf->address);
> > 4009 if (folio)
> > 4010 page = folio_file_page(folio, swp_offset(entry));
> > 4011 swapcache = folio;
> > 4012
> > 4013 if (!folio) {
> > 4014 if (data_race(si->flags & SWP_SYNCHRONOUS_IO) &&
> > 4015 __swap_count(entry) == 1) {
> > 4016 /*
> > 4017 * Prevent parallel swapin from proceeding with
> > 4018 * the cache flag. Otherwise, another thread may
> > 4019 * finish swapin first, free the entry, and swapout
> > 4020 * reusing the same entry. It's undetectable as
> > 4021 * pte_same() returns true due to entry reuse.
> > 4022 */
> > 4023 if (swapcache_prepare(entry)) {
> > 4024 /* Relax a bit to prevent rapid repeated page faults */
> > 4025 schedule_timeout_uninterruptible(1);
> > 4026 goto out;
> > 4027 }
> > 4028 need_clear_cache = true;
> > 4029
> > 4030 /* skip swapcache */
> > 4031 folio = vma_alloc_folio(GFP_HIGHUSER_MOVABLE, 0,
> > 4032 vma, vmf->address, false);
> > 4033 page = &folio->page;
> > 4034 if (folio) {
> > 4035 __folio_set_locked(folio);
> > 4036 __folio_set_swapbacked(folio);
> > 4037
> > 4038 if (mem_cgroup_swapin_charge_folio(folio,
> > 4039 vma->vm_mm, GFP_KERNEL,
> > 4040 entry)) {
> > 4041 ret = VM_FAULT_OOM;
> > 4042 goto out_page;
> > 4043 }
> > 4044 mem_cgroup_swapin_uncharge_swap(entry);
> > 4045
> > 4046 shadow = get_shadow_from_swap_cache(entry);
> > 4047 if (shadow)
> > 4048 workingset_refault(folio, shadow);
> > 4049
> > 4050 folio_add_lru(folio);
> > 4051
> > 4052 /* To provide entry to swap_read_folio() */
> > 4053 folio->swap = entry;
> > 4054 swap_read_folio(folio, true, NULL);
> > 4055 folio->private = NULL;
> > 4056 }
> > 4057 } else {
> > 4058 page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE,
> > 4059 vmf);
> > 4060 if (page)
> > 4061 folio = page_folio(page);
> > 4062 swapcache = folio;
> > 4063 }
> > 4064
> > 4065 if (!folio) {
> > 4066 /*
> > 4067 * Back out if somebody else faulted in this pte
> > 4068 * while we released the pte lock.
> > 4069 */
> > 4070 vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd,
> > 4071 vmf->address, &vmf->ptl);
> > 4072 if (likely(vmf->pte &&
> > 4073 pte_same(ptep_get(vmf->pte), vmf->orig_pte)))
> > 4074 ret = VM_FAULT_OOM;
> > 4075 goto unlock;
> > 4076 }
> > 4077
> > 4078 /* Had to read the page from swap area: Major fault */
> > 4079 ret = VM_FAULT_MAJOR;
> > 4080 count_vm_event(PGMAJFAULT);
> > 4081 count_memcg_event_mm(vma->vm_mm, PGMAJFAULT);
> > 4082 } else if (PageHWPoison(page)) {
> > 4083 /*
> > 4084 * hwpoisoned dirty swapcache pages are kept for killing
> > 4085 * owner processes (which may be unknown at hwpoison time)
> > 4086 */
> > 4087 ret = VM_FAULT_HWPOISON;
> > 4088 goto out_release;
> > 4089 }
> > 4090
> > 4091 ret |= folio_lock_or_retry(folio, vmf);
> > 4092 if (ret & VM_FAULT_RETRY)
> > 4093 goto out_release;
> > 4094
> > 4095 if (swapcache) {
> > 4096 /*
> > 4097 * Make sure folio_free_swap() or swapoff did not release the
> > 4098 * swapcache from under us. The page pin, and pte_same test
> > 4099 * below, are not enough to exclude that. Even if it is still
> > 4100 * swapcache, we need to check that the page's swap has not
> > 4101 * changed.
> > 4102 */
> > 4103 if (unlikely(!folio_test_swapcache(folio) ||
> > 4104 page_swap_entry(page).val != entry.val))
> > 4105 goto out_page;
> > 4106
> > 4107 /*
> > 4108 * KSM sometimes has to copy on read faults, for example, if
> > 4109 * page->index of !PageKSM() pages would be nonlinear inside the
> > 4110 * anon VMA -- PageKSM() is lost on actual swapout.
> > 4111 */
> > 4112 folio = ksm_might_need_to_copy(folio, vma, vmf->address);
> > 4113 if (unlikely(!folio)) {
> > 4114 ret = VM_FAULT_OOM;
> > 4115 folio = swapcache;
> > 4116 goto out_page;
> > 4117 } else if (unlikely(folio == ERR_PTR(-EHWPOISON))) {
> > 4118 ret = VM_FAULT_HWPOISON;
> > 4119 folio = swapcache;
> > 4120 goto out_page;
> > 4121 }
> > 4122 if (folio != swapcache)
> > 4123 page = folio_page(folio, 0);
> > 4124
> > 4125 /*
> > 4126 * If we want to map a page that's in the swapcache writable, we
> > 4127 * have to detect via the refcount if we're really the exclusive
> > 4128 * owner. Try removing the extra reference from the local LRU
> > 4129 * caches if required.
> > 4130 */
> > 4131 if ((vmf->flags & FAULT_FLAG_WRITE) && folio == swapcache &&
> > 4132 !folio_test_ksm(folio) && !folio_test_lru(folio))
> > 4133 lru_add_drain();
> > 4134 }
> > 4135
> > 4136 folio_throttle_swaprate(folio, GFP_KERNEL);
> > 4137
> > 4138 /*
> > 4139 * Back out if somebody else already faulted in this pte.
> > 4140 */
> > 4141 vmf->pte = pte_offset_map_lock(vma->vm_mm, vmf->pmd, vmf->address,
> > 4142 &vmf->ptl);
> > 4143
> > 4144 /* We hit large folios in swapcache */
> > 4145 if (start_pte && folio_test_large(folio) && folio_test_swapcache(folio)) {
> > 4146 int nr = folio_nr_pages(folio);
> > 4147 int idx = folio_page_idx(folio, page);
> > 4148 unsigned long folio_start = vmf->address - idx * PAGE_SIZE;
> > 4149 unsigned long folio_end = folio_start + nr * PAGE_SIZE;
> > 4150 pte_t *folio_ptep;
> > 4151 pte_t folio_pte;
> > 4152
> > 4153 if (unlikely(folio_start < max(vmf->address & PMD_MASK, vma->vm_start)))
> > 4154 goto check_pte;
> > 4155 if (unlikely(folio_end > pmd_addr_end(vmf->address, vma->vm_end)))
> > 4156 goto check_pte;
> > 4157
> > 4158 folio_ptep = vmf->pte - idx;
> > 4159 folio_pte = ptep_get(folio_ptep);
> > 4160 if (!is_swap_pte(folio_pte) || non_swap_entry(pte_to_swp_entry(folio_pte)) ||
> > 4161 swap_pte_batch(folio_ptep, nr, folio_pte, &any_swap_shared) != nr)
> > 4162 goto check_pte;
> > 4163
> > 4164 start_address = folio_start;
> > 4165 start_pte = folio_ptep;
> > 4166 nr_pages = nr;
> > 4167 entry = folio->swap;
> > 4168 page = &folio->page;
> > > 4169 count_mthp_stat(folio_order(folio), MTHP_STAT_ANON_SWPIN_REFAULT);
> > 4170 }
> > 4171
> > 4172 check_pte:
> > 4173 if (unlikely(!vmf->pte || !pte_same(ptep_get(vmf->pte), vmf->orig_pte)))
> > 4174 goto out_nomap;
> > 4175
> > 4176 if (unlikely(!folio_test_uptodate(folio))) {
> > 4177 ret = VM_FAULT_SIGBUS;
> > 4178 goto out_nomap;
> > 4179 }
> > 4180
> > 4181 /*
> > 4182 * PG_anon_exclusive reuses PG_mappedtodisk for anon pages. A swap pte
> > 4183 * must never point at an anonymous page in the swapcache that is
> > 4184 * PG_anon_exclusive. Sanity check that this holds and especially, that
> > 4185 * no filesystem set PG_mappedtodisk on a page in the swapcache. Sanity
> > 4186 * check after taking the PT lock and making sure that nobody
> > 4187 * concurrently faulted in this page and set PG_anon_exclusive.
> > 4188 */
> > 4189 BUG_ON(!folio_test_anon(folio) && folio_test_mappedtodisk(folio));
> > 4190 BUG_ON(folio_test_anon(folio) && PageAnonExclusive(page));
> > 4191
> > 4192 /*
> > 4193 * Check under PT lock (to protect against concurrent fork() sharing
> > 4194 * the swap entry concurrently) for certainly exclusive pages.
> > 4195 */
> > 4196 if (!folio_test_ksm(folio)) {
> > 4197 exclusive = pte_swp_exclusive(vmf->orig_pte);
> > 4198 if (folio != swapcache) {
> > 4199 /*
> > 4200 * We have a fresh page that is not exposed to the
> > 4201 * swapcache -> certainly exclusive.
> > 4202 */
> > 4203 exclusive = true;
> > 4204 } else if (exclusive && folio_test_writeback(folio) &&
> > 4205 data_race(si->flags & SWP_STABLE_WRITES)) {
> > 4206 /*
> > 4207 * This is tricky: not all swap backends support
> > 4208 * concurrent page modifications while under writeback.
> > 4209 *
> > 4210 * So if we stumble over such a page in the swapcache
> > 4211 * we must not set the page exclusive, otherwise we can
> > 4212 * map it writable without further checks and modify it
> > 4213 * while still under writeback.
> > 4214 *
> > 4215 * For these problematic swap backends, simply drop the
> > 4216 * exclusive marker: this is perfectly fine as we start
> > 4217 * writeback only if we fully unmapped the page and
> > 4218 * there are no unexpected references on the page after
> > 4219 * unmapping succeeded. After fully unmapped, no
> > 4220 * further GUP references (FOLL_GET and FOLL_PIN) can
> > 4221 * appear, so dropping the exclusive marker and mapping
> > 4222 * it only R/O is fine.
> > 4223 */
> > 4224 exclusive = false;
> > 4225 }
> > 4226
> > 4227 /* Reuse the whole large folio iff all entries are exclusive */
> > 4228 if (nr_pages > 1 && any_swap_shared)
> > 4229 exclusive = false;
> > 4230 }
> > 4231
> > 4232 /*
> > 4233 * Some architectures may have to restore extra metadata to the page
> > 4234 * when reading from swap. This metadata may be indexed by swap entry
> > 4235 * so this must be called before swap_free().
> > 4236 */
> > 4237 arch_swap_restore(folio_swap(entry, folio), folio);
> > 4238
> > 4239 /*
> > 4240 * Remove the swap entry and conditionally try to free up the swapcache.
> > 4241 * We're already holding a reference on the page but haven't mapped it
> > 4242 * yet.
> > 4243 */
> > 4244 swap_free_nr(entry, nr_pages);
> > 4245 if (should_try_to_free_swap(folio, vma, vmf->flags))
> > 4246 folio_free_swap(folio);
> > 4247
> > 4248 folio_ref_add(folio, nr_pages - 1);
> > 4249 add_mm_counter(vma->vm_mm, MM_ANONPAGES, nr_pages);
> > 4250 add_mm_counter(vma->vm_mm, MM_SWAPENTS, -nr_pages);
> > 4251
> > 4252 pte = mk_pte(page, vma->vm_page_prot);
> > 4253
> > 4254 /*
> > 4255 * Same logic as in do_wp_page(); however, optimize for pages that are
> > 4256 * certainly not shared either because we just allocated them without
> > 4257 * exposing them to the swapcache or because the swap entry indicates
> > 4258 * exclusivity.
> > 4259 */
> > 4260 if (!folio_test_ksm(folio) &&
> > 4261 (exclusive || (folio_ref_count(folio) == nr_pages &&
> > 4262 folio_nr_pages(folio) == nr_pages))) {
> > 4263 if (vmf->flags & FAULT_FLAG_WRITE) {
> > 4264 pte = maybe_mkwrite(pte_mkdirty(pte), vma);
> > 4265 vmf->flags &= ~FAULT_FLAG_WRITE;
> > 4266 }
> > 4267 rmap_flags |= RMAP_EXCLUSIVE;
> > 4268 }
> > 4269 flush_icache_pages(vma, page, nr_pages);
> > 4270 if (pte_swp_soft_dirty(vmf->orig_pte))
> > 4271 pte = pte_mksoft_dirty(pte);
> > 4272 if (pte_swp_uffd_wp(vmf->orig_pte))
> > 4273 pte = pte_mkuffd_wp(pte);
> > 4274
> > 4275 /* ksm created a completely new copy */
> > 4276 if (unlikely(folio != swapcache && swapcache)) {
> > 4277 folio_add_new_anon_rmap(folio, vma, start_address);
> > 4278 folio_add_lru_vma(folio, vma);
> > 4279 } else {
> > 4280 folio_add_anon_rmap_ptes(folio, page, nr_pages, vma, start_address,
> > 4281 rmap_flags);
> > 4282 }
> > 4283
> > 4284 VM_BUG_ON(!folio_test_anon(folio) ||
> > 4285 (pte_write(pte) && !PageAnonExclusive(page)));
> > 4286 set_ptes(vma->vm_mm, start_address, start_pte, pte, nr_pages);
> > 4287 vmf->orig_pte = ptep_get(vmf->pte);
> > 4288 arch_do_swap_page(vma->vm_mm, vma, start_address, pte, pte);
> > 4289
> > 4290 folio_unlock(folio);
> > 4291 if (folio != swapcache && swapcache) {
> > 4292 /*
> > 4293 * Hold the lock to avoid the swap entry to be reused
> > 4294 * until we take the PT lock for the pte_same() check
> > 4295 * (to avoid false positives from pte_same). For
> > 4296 * further safety release the lock after the swap_free
> > 4297 * so that the swap count won't change under a
> > 4298 * parallel locked swapcache.
> > 4299 */
> > 4300 folio_unlock(swapcache);
> > 4301 folio_put(swapcache);
> > 4302 }
> > 4303
> > 4304 if (vmf->flags & FAULT_FLAG_WRITE) {
> > 4305 ret |= do_wp_page(vmf);
> > 4306 if (ret & VM_FAULT_ERROR)
> > 4307 ret &= VM_FAULT_ERROR;
> > 4308 goto out;
> > 4309 }
> > 4310
> > 4311 /* No need to invalidate - it was non-present before */
> > 4312 update_mmu_cache_range(vmf, vma, start_address, start_pte, nr_pages);
> > 4313 unlock:
> > 4314 if (vmf->pte)
> > 4315 pte_unmap_unlock(vmf->pte, vmf->ptl);
> > 4316 out:
> > 4317 /* Clear the swap cache pin for direct swapin after PTL unlock */
> > 4318 if (need_clear_cache)
> > 4319 swapcache_clear(si, entry);
> > 4320 if (si)
> > 4321 put_swap_device(si);
> > 4322 return ret;
> > 4323 out_nomap:
> > 4324 if (vmf->pte)
> > 4325 pte_unmap_unlock(vmf->pte, vmf->ptl);
> > 4326 out_page:
> > 4327 folio_unlock(folio);
> > 4328 out_release:
> > 4329 folio_put(folio);
> > 4330 if (folio != swapcache && swapcache) {
> > 4331 folio_unlock(swapcache);
> > 4332 folio_put(swapcache);
> > 4333 }
> > 4334 if (need_clear_cache)
> > 4335 swapcache_clear(si, entry);
> > 4336 if (si)
> > 4337 put_swap_device(si);
> > 4338 return ret;
> > 4339 }
> > 4340
> >
> > --
> > 0-DAY CI Kernel Test Service
> > https://github.com/intel/lkp-tests/wiki
> >
>
prev parent reply other threads:[~2024-04-12 2:58 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-04-11 9:47 kernel test robot
2024-04-11 10:07 ` Barry Song
2024-04-12 2:58 ` Liu, Yujie [this message]
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