The patch titled Subject: nfs: disable data cache revalidation for swapfiles has been added to the -mm tree. Its filename is nfs-disable-data-cache-revalidation-for-swapfiles.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Mel Gorman <mgorman@xxxxxxx> Subject: nfs: disable data cache revalidation for swapfiles The VM does not like PG_private set on PG_swapcache pages. As suggested by Trond in http://lkml.org/lkml/2006/8/25/348, this patch disables NFS data cache revalidation on swap files. as it does not make sense to have other clients change the file while it is being used as swap. This avoids setting PG_private on swap pages, since there ought to be no further races with invalidate_inode_pages2() to deal with. Since we cannot set PG_private we cannot use page->private which is already used by PG_swapcache pages to store the nfs_page. Thus augment the new nfs_page_find_request logic. Signed-off-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx> Signed-off-by: Mel Gorman <mgorman@xxxxxxx> Acked-by: Rik van Riel <riel@xxxxxxxxxx> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx> Cc: David S. Miller <davem@xxxxxxxxxxxxx> Cc: Eric B Munson <emunson@xxxxxxxxx> Cc: Eric Paris <eparis@xxxxxxxxxx> Cc: James Morris <jmorris@xxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxx> Cc: Mike Christie <michaelc@xxxxxxxxxxx> Cc: Neil Brown <neilb@xxxxxxx> Cc: Sebastian Andrzej Siewior <sebastian@xxxxxxxxxxxxx> Cc: Trond Myklebust <Trond.Myklebust@xxxxxxxxxx> Cc: Xiaotian Feng <dfeng@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- fs/nfs/inode.c | 4 +++ fs/nfs/write.c | 49 +++++++++++++++++++++++++++++++++-------------- 2 files changed, 39 insertions(+), 14 deletions(-) diff -puN fs/nfs/inode.c~nfs-disable-data-cache-revalidation-for-swapfiles fs/nfs/inode.c --- a/fs/nfs/inode.c~nfs-disable-data-cache-revalidation-for-swapfiles +++ a/fs/nfs/inode.c @@ -883,6 +883,10 @@ int nfs_revalidate_mapping(struct inode struct nfs_inode *nfsi = NFS_I(inode); int ret = 0; + /* swapfiles are not supposed to be shared. */ + if (IS_SWAPFILE(inode)) + goto out; + if (nfs_mapping_need_revalidate_inode(inode)) { ret = __nfs_revalidate_inode(NFS_SERVER(inode), inode); if (ret < 0) diff -puN fs/nfs/write.c~nfs-disable-data-cache-revalidation-for-swapfiles fs/nfs/write.c --- a/fs/nfs/write.c~nfs-disable-data-cache-revalidation-for-swapfiles +++ a/fs/nfs/write.c @@ -139,15 +139,28 @@ static void nfs_context_set_write_error( set_bit(NFS_CONTEXT_ERROR_WRITE, &ctx->flags); } -static struct nfs_page *nfs_page_find_request_locked(struct page *page) +static struct nfs_page * +nfs_page_find_request_locked(struct nfs_inode *nfsi, struct page *page) { struct nfs_page *req = NULL; - if (PagePrivate(page)) { + if (PagePrivate(page)) req = (struct nfs_page *)page_private(page); - if (req != NULL) - kref_get(&req->wb_kref); + else if (unlikely(PageSwapCache(page))) { + struct nfs_page *freq, *t; + + /* Linearly search the commit list for the correct req */ + list_for_each_entry_safe(freq, t, &nfsi->commit_info.list, wb_list) { + if (freq->wb_page == page) { + req = freq; + break; + } + } } + + if (req) + kref_get(&req->wb_kref); + return req; } @@ -157,7 +170,7 @@ static struct nfs_page *nfs_page_find_re struct nfs_page *req = NULL; spin_lock(&inode->i_lock); - req = nfs_page_find_request_locked(page); + req = nfs_page_find_request_locked(NFS_I(inode), page); spin_unlock(&inode->i_lock); return req; } @@ -258,7 +271,7 @@ static struct nfs_page *nfs_find_and_loc spin_lock(&inode->i_lock); for (;;) { - req = nfs_page_find_request_locked(page); + req = nfs_page_find_request_locked(NFS_I(inode), page); if (req == NULL) break; if (nfs_lock_request(req)) @@ -413,9 +426,15 @@ static void nfs_inode_add_request(struct spin_lock(&inode->i_lock); if (!nfsi->npages && NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) inode->i_version++; - set_bit(PG_MAPPED, &req->wb_flags); - SetPagePrivate(req->wb_page); - set_page_private(req->wb_page, (unsigned long)req); + /* + * Swap-space should not get truncated. Hence no need to plug the race + * with invalidate/truncate. + */ + if (likely(!PageSwapCache(req->wb_page))) { + set_bit(PG_MAPPED, &req->wb_flags); + SetPagePrivate(req->wb_page); + set_page_private(req->wb_page, (unsigned long)req); + } nfsi->npages++; kref_get(&req->wb_kref); spin_unlock(&inode->i_lock); @@ -432,9 +451,11 @@ static void nfs_inode_remove_request(str BUG_ON (!NFS_WBACK_BUSY(req)); spin_lock(&inode->i_lock); - set_page_private(req->wb_page, 0); - ClearPagePrivate(req->wb_page); - clear_bit(PG_MAPPED, &req->wb_flags); + if (likely(!PageSwapCache(req->wb_page))) { + set_page_private(req->wb_page, 0); + ClearPagePrivate(req->wb_page); + clear_bit(PG_MAPPED, &req->wb_flags); + } nfsi->npages--; spin_unlock(&inode->i_lock); nfs_release_request(req); @@ -730,7 +751,7 @@ static struct nfs_page *nfs_try_to_updat spin_lock(&inode->i_lock); for (;;) { - req = nfs_page_find_request_locked(page); + req = nfs_page_find_request_locked(NFS_I(inode), page); if (req == NULL) goto out_unlock; @@ -1744,7 +1765,7 @@ int nfs_wb_page_cancel(struct inode *ino */ int nfs_wb_page(struct inode *inode, struct page *page) { - loff_t range_start = page_offset(page); + loff_t range_start = page_file_offset(page); loff_t range_end = range_start + (loff_t)(PAGE_CACHE_SIZE - 1); struct writeback_control wbc = { .sync_mode = WB_SYNC_ALL, _ Subject: Subject: nfs: disable data cache revalidation for swapfiles Patches currently in -mm which might be from mgorman@xxxxxxx are origin.patch linux-next.patch memcg-prevent-oom-with-too-many-dirty-pages.patch memcg-prevent-oom-with-too-many-dirty-pages-fix.patch mm-do-not-use-page_count-without-a-page-pin.patch mm-clean-up-__count_immobile_pages.patch mm-hotplug-correctly-setup-fallback-zonelists-when-creating-new-pgdat.patch mm-hotplug-correctly-add-new-zone-to-all-other-nodes-zone-lists.patch mm-hotplug-free-zone-pageset-when-a-zone-becomes-empty.patch mm-hotplug-mark-memory-hotplug-code-in-page_allocc-as-__meminit.patch mm-factor-out-memory-isolate-functions.patch mm-bug-fix-free-page-check-in-zone_watermark_ok.patch memory-hotplug-fix-kswapd-looping-forever-problem.patch memory-hotplug-fix-kswapd-looping-forever-problem-fix.patch mm-slb-add-knowledge-of-pfmemalloc-reserve-pages.patch mm-slub-optimise-the-slub-fast-path-to-avoid-pfmemalloc-checks.patch mm-introduce-__gfp_memalloc-to-allow-access-to-emergency-reserves.patch mm-allow-pf_memalloc-from-softirq-context.patch mm-only-set-page-pfmemalloc-when-alloc_no_watermarks-was-used.patch mm-ignore-mempolicies-when-using-alloc_no_watermark.patch net-introduce-sk_gfp_atomic-to-allow-addition-of-gfp-flags-depending-on-the-individual-socket.patch netvm-allow-the-use-of-__gfp_memalloc-by-specific-sockets.patch netvm-allow-skb-allocation-to-use-pfmemalloc-reserves.patch netvm-propagate-page-pfmemalloc-to-skb.patch netvm-propagate-page-pfmemalloc-from-skb_alloc_page-to-skb.patch netvm-set-pf_memalloc-as-appropriate-during-skb-processing.patch mm-micro-optimise-slab-to-avoid-a-function-call.patch nbd-set-sock_memalloc-for-access-to-pfmemalloc-reserves.patch mm-throttle-direct-reclaimers-if-pf_memalloc-reserves-are-low-and-swap-is-backed-by-network-storage.patch mm-account-for-the-number-of-times-direct-reclaimers-get-throttled.patch netvm-prevent-a-stream-specific-deadlock.patch selinux-tag-avc-cache-alloc-as-non-critical.patch mm-methods-for-teaching-filesystems-about-pg_swapcache-pages.patch mm-add-support-for-a-filesystem-to-activate-swap-files-and-use-direct_io-for-writing-swap-pages.patch mm-swap-implement-generic-handler-for-swap_activate.patch mm-add-get_kernel_page-for-pinning-of-kernel-addresses-for-i-o.patch mm-add-support-for-direct_io-to-highmem-pages.patch nfs-teach-the-nfs-client-how-to-treat-pg_swapcache-pages.patch nfs-disable-data-cache-revalidation-for-swapfiles.patch nfs-enable-swap-on-nfs.patch nfs-prevent-page-allocator-recursions-with-swap-over-nfs.patch swapfile-avoid-dereferencing-bd_disk-during-swap_entry_free-for-network-storage.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html