Messages in this thread | | | Subject | Re: [PATCH] mm, soft-offline: convert parameter to pfn | From | David Hildenbrand <> | Date | Wed, 16 Oct 2019 10:57:57 +0200 |
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On 16.10.19 10:54, Naoya Horiguchi wrote: > On Wed, Oct 16, 2019 at 10:34:52AM +0200, David Hildenbrand wrote: >> On 16.10.19 10:27, Naoya Horiguchi wrote: >>> On Wed, Oct 16, 2019 at 09:56:19AM +0200, David Hildenbrand wrote: >>>> On 16.10.19 09:09, Naoya Horiguchi wrote: >>>>> Hi, >>>>> >>>>> I wrote a simple cleanup for parameter of soft_offline_page(), >>>>> based on thread https://lkml.org/lkml/2019/10/11/57. >>>>> >>>>> I know that we need more cleanup on hwpoison-inject, but I think >>>>> that will be mentioned in re-write patchset Oscar is preparing now. >>>>> So let me shared only this part as a separate one now. >>> ... >>>> >>>> I think you should rebase that patch on linux-next (where the >>>> pfn_to_online_page() check is in place). I assume you'll want to move the >>>> pfn_to_online_page() check into soft_offline_page() then as well? >>> >>> I rebased to next-20191016. And yes, we will move pfn_to_online_page() >>> into soft offline code. It seems that we can also move pfn_valid(), >>> but is simply moving like below good enough for you? >> >> At least I can't am the patch to current next/master (due to >> pfn_to_online_page()).
Could also be that my "git am" skills failed as the mail was not a proper patch itself :)
>> >>> >>> @@ -1877,11 +1877,17 @@ static int soft_offline_free_page(struct page *page) >>> * This is not a 100% solution for all memory, but tries to be >>> * ``good enough'' for the majority of memory. >>> */ >>> -int soft_offline_page(struct page *page, int flags) >>> +int soft_offline_page(unsigned long pfn, int flags) >>> { >>> int ret; >>> - unsigned long pfn = page_to_pfn(page); >>> + struct page *page; >>> + if (!pfn_valid(pfn)) >>> + return -ENXIO; >>> + /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ >>> + if (!pfn_to_online_page(pfn)) >>> + return -EIO; >>> + page = pfn_to_page(pfn); >>> if (is_zone_device_page(page)) { >>> pr_debug_ratelimited("soft_offline: %#lx page is device page\n", >>> pfn); >>> -- >>> >>> Or we might have an option to do as memory_failure() does like below: >> >> In contrast to soft offlining, memory failure can deal with devmem. So I >> think the above makes sense. > > OK, so here's the revised one. > > Thanks, > Naoya Horiguchi > --- > From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > Date: Wed, 16 Oct 2019 17:00:33 +0900 > Subject: [PATCH] mm, soft-offline: convert parameter to pfn > > Currently soft_offline_page() receives struct page, and its sibling > memory_failure() receives pfn. This discrepancy looks weird and makes > precheck on pfn validity tricky. So let's align them. > > Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> > --- > drivers/base/memory.c | 7 +------ > include/linux/mm.h | 2 +- > mm/madvise.c | 2 +- > mm/memory-failure.c | 14 ++++++++++---- > 4 files changed, 13 insertions(+), 12 deletions(-) > > diff --git a/drivers/base/memory.c b/drivers/base/memory.c > index 55907c27075b..a757d9ed88a7 100644 > --- a/drivers/base/memory.c > +++ b/drivers/base/memory.c > @@ -538,12 +538,7 @@ static ssize_t soft_offline_page_store(struct device *dev, > if (kstrtoull(buf, 0, &pfn) < 0) > return -EINVAL; > pfn >>= PAGE_SHIFT; > - if (!pfn_valid(pfn)) > - return -ENXIO; > - /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ > - if (!pfn_to_online_page(pfn)) > - return -EIO; > - ret = soft_offline_page(pfn_to_page(pfn), 0); > + ret = soft_offline_page(pfn, 0); > return ret == 0 ? count : ret; > } > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 44d058723db9..fd360d208346 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -2794,7 +2794,7 @@ extern int sysctl_memory_failure_early_kill; > extern int sysctl_memory_failure_recovery; > extern void shake_page(struct page *p, int access); > extern atomic_long_t num_poisoned_pages __read_mostly; > -extern int soft_offline_page(struct page *page, int flags); > +extern int soft_offline_page(unsigned long pfn, int flags); > > > /* > diff --git a/mm/madvise.c b/mm/madvise.c > index 2be9f3fdb05e..99dd06fecfa9 100644 > --- a/mm/madvise.c > +++ b/mm/madvise.c > @@ -887,7 +887,7 @@ static int madvise_inject_error(int behavior, > pr_info("Soft offlining pfn %#lx at process virtual address %#lx\n", > pfn, start); > > - ret = soft_offline_page(page, MF_COUNT_INCREASED); > + ret = soft_offline_page(pfn, MF_COUNT_INCREASED); > if (ret) > return ret; > continue; > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > index 05c8c6df25e6..bdf408d7f65c 100644 > --- a/mm/memory-failure.c > +++ b/mm/memory-failure.c > @@ -1476,7 +1476,7 @@ static void memory_failure_work_func(struct work_struct *work) > if (!gotten) > break; > if (entry.flags & MF_SOFT_OFFLINE) > - soft_offline_page(pfn_to_page(entry.pfn), entry.flags); > + soft_offline_page(entry.pfn, entry.flags); > else > memory_failure(entry.pfn, entry.flags); > } > @@ -1857,7 +1857,7 @@ static int soft_offline_free_page(struct page *page) > > /** > * soft_offline_page - Soft offline a page. > - * @page: page to offline > + * @pfn: pfn to soft-offline > * @flags: flags. Same as memory_failure(). > * > * Returns 0 on success, otherwise negated errno. > @@ -1877,11 +1877,17 @@ static int soft_offline_free_page(struct page *page) > * This is not a 100% solution for all memory, but tries to be > * ``good enough'' for the majority of memory. > */ > -int soft_offline_page(struct page *page, int flags) > +int soft_offline_page(unsigned long pfn, int flags) > { > int ret; > - unsigned long pfn = page_to_pfn(page); > + struct page *page; > > + if (!pfn_valid(pfn)) > + return -ENXIO; > + /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ > + page = pfn_to_online_page(pfn); > + if (!page) > + return -EIO; > if (is_zone_device_page(page)) {
-> this is now no longer possible! So you can drop the whole if (is_zone_device....) case
> pr_debug_ratelimited("soft_offline: %#lx page is device page\n", > pfn); >
Apart from that, looks good to me.
--
Thanks,
David / dhildenb
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