From: Matthew Wilcox <willy@infradead.org>
To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org
Cc: Matthew Wilcox <willy@infradead.org>, Jan Kara <jack@suse.cz>,
Jeff Layton <jlayton@redhat.com>,
Lukas Czerner <lczerner@redhat.com>,
Ross Zwisler <ross.zwisler@linux.intel.com>,
Christoph Hellwig <hch@lst.de>,
Goldwyn Rodrigues <rgoldwyn@suse.com>,
Nicholas Piggin <npiggin@gmail.com>,
Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>,
linux-nilfs@vger.kernel.org, Jaegeuk Kim <jaegeuk@kernel.org>,
Chao Yu <yuchao0@huawei.com>,
linux-f2fs-devel@lists.sourceforge.net
Subject: [PATCH v14 17/74] xarray: Add xas_for_each_conflict
Date: Sat, 16 Jun 2018 18:59:55 -0700 [thread overview]
Message-ID: <20180617020052.4759-18-willy@infradead.org> (raw)
In-Reply-To: <20180617020052.4759-1-willy@infradead.org>
This iterator iterates over each entry that is stored in the index or
indices specified by the xa_state. This is intended for use for a
conditional store of a multiindex entry, or to allow entries which are
about to be removed from the xarray to be disposed of properly.
Signed-off-by: Matthew Wilcox <willy@infradead.org>
---
include/linux/xarray.h | 17 ++++++++++++
lib/test_xarray.c | 63 ++++++++++++++++++++++++++++++++++++++++++
lib/xarray.c | 61 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 141 insertions(+)
diff --git a/include/linux/xarray.h b/include/linux/xarray.h
index 921d41034d7d..0a9f66266c9a 100644
--- a/include/linux/xarray.h
+++ b/include/linux/xarray.h
@@ -769,6 +769,7 @@ static inline bool xas_retry(struct xa_state *xas, const void *entry)
void *xas_load(struct xa_state *);
void *xas_store(struct xa_state *, void *entry);
void *xas_find(struct xa_state *, unsigned long max);
+void *xas_next_conflict(struct xa_state *);
bool xas_get_tag(const struct xa_state *, xa_tag_t);
void xas_set_tag(const struct xa_state *, xa_tag_t);
@@ -983,6 +984,22 @@ enum {
for (entry = xas_find_tagged(xas, max, tag); entry; \
entry = xas_next_tagged(xas, max, tag))
+/**
+ * xas_for_each_conflict() - Iterate over a range of an XArray.
+ * @xas: XArray operation state.
+ * @entry: Entry retrieved from the array.
+ *
+ * The loop body will be executed for each entry in the XArray that lies
+ * within the range specified by @xas. If the loop completes successfully,
+ * any entries that lie in this range will be replaced by @entry. The caller
+ * may break out of the loop; if they do so, the contents of the XArray will
+ * be unchanged. The operation may fail due to an out of memory condition.
+ * The caller may also call xa_set_err() to exit the loop while setting an
+ * error to record the reason.
+ */
+#define xas_for_each_conflict(xas, entry) \
+ while ((entry = xas_next_conflict(xas)))
+
void *__xas_next(struct xa_state *);
void *__xas_prev(struct xa_state *);
diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index e74ade12c663..818cfd8746ba 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -315,6 +315,68 @@ static void check_multi_store(struct xarray *xa)
}
}
+static void __check_store_iter(struct xarray *xa, unsigned long start,
+ unsigned int order, unsigned int present)
+{
+ XA_STATE_ORDER(xas, xa, start, order);
+ void *entry;
+ unsigned int count = 0;
+
+retry:
+ xas_for_each_conflict(&xas, entry) {
+ XA_BUG_ON(xa, !xa_is_value(entry));
+ XA_BUG_ON(xa, entry < xa_mk_value(start));
+ XA_BUG_ON(xa, entry > xa_mk_value(start + (1UL << order) - 1));
+ count++;
+ }
+ xas_store(&xas, xa_mk_value(start));
+ if (xas_nomem(&xas, GFP_KERNEL)) {
+ count = 0;
+ goto retry;
+ }
+ XA_BUG_ON(xa, xas_error(&xas));
+ XA_BUG_ON(xa, count != present);
+ XA_BUG_ON(xa, xa_load(xa, start) != xa_mk_value(start));
+ XA_BUG_ON(xa, xa_load(xa, start + (1UL << order) - 1) !=
+ xa_mk_value(start));
+ xa_erase_value(xa, start);
+}
+
+static void check_store_iter(struct xarray *xa)
+{
+ unsigned int i, j;
+
+ for (i = 0; i < 20; i++) {
+ unsigned int min = 1 << i;
+ unsigned int max = (2 << i) - 1;
+ __check_store_iter(xa, 0, i, 0);
+ XA_BUG_ON(xa, !xa_empty(xa));
+ __check_store_iter(xa, min, i, 0);
+ XA_BUG_ON(xa, !xa_empty(xa));
+
+ xa_store_value(xa, min, GFP_KERNEL);
+ __check_store_iter(xa, min, i, 1);
+ XA_BUG_ON(xa, !xa_empty(xa));
+ xa_store_value(xa, max, GFP_KERNEL);
+ __check_store_iter(xa, min, i, 1);
+ XA_BUG_ON(xa, !xa_empty(xa));
+
+ for (j = 0; j < min; j++)
+ xa_store_value(xa, j, GFP_KERNEL);
+ __check_store_iter(xa, 0, i, min);
+ XA_BUG_ON(xa, !xa_empty(xa));
+ for (j = 0; j < min; j++)
+ xa_store_value(xa, min + j, GFP_KERNEL);
+ __check_store_iter(xa, min, i, min);
+ XA_BUG_ON(xa, !xa_empty(xa));
+ }
+ xa_store_value(xa, 63, GFP_KERNEL);
+ xa_store_value(xa, 65, GFP_KERNEL);
+ __check_store_iter(xa, 64, 2, 1);
+ xa_erase_value(xa, 63);
+ XA_BUG_ON(xa, !xa_empty(xa));
+}
+
static void check_multi_find(struct xarray *xa)
{
unsigned long index;
@@ -506,6 +568,7 @@ static int xarray_checks(void)
check_multi_store(&array);
check_find(&array);
check_move(&array);
+ check_store_iter(&array);
printk("XArray: %u of %u tests passed\n", tests_passed, tests_run);
return (tests_run != tests_passed) ? 0 : -EINVAL;
diff --git a/lib/xarray.c b/lib/xarray.c
index ab1b6786711e..31c5332c8146 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -1086,6 +1086,67 @@ void *xas_find_tagged(struct xa_state *xas, unsigned long max, xa_tag_t tag)
}
EXPORT_SYMBOL_GPL(xas_find_tagged);
+/**
+ * xas_next_conflict() - Step for xas_for_each_conflict().
+ * @xas: XArray operation state.
+ *
+ * This function does the work for xas_for_each_conflict().
+ *
+ * Context: Any context. Expects xa_lock to be held.
+ * Return: The next entry in the range covered by @xas or %NULL.
+ */
+void *xas_next_conflict(struct xa_state *xas)
+{
+ void *curr;
+
+ if (xas_error(xas))
+ return NULL;
+
+ if (!xas->xa_node)
+ return NULL;
+
+ if (xas_top(xas->xa_node)) {
+ curr = xas_start(xas);
+ if (!curr)
+ return NULL;
+ while (xa_is_node(curr)) {
+ struct xa_node *node = xa_to_node(curr);
+ curr = xas_descend(xas, node);
+ }
+ if (curr)
+ return curr;
+ }
+
+ if (xas->xa_node->shift > xas->xa_shift)
+ return NULL;
+
+ for (;;) {
+ if (xas->xa_node->shift == xas->xa_shift) {
+ if ((xas->xa_offset & xas->xa_sibs) == xas->xa_sibs)
+ break;
+ } else if (xas->xa_offset == XA_CHUNK_MASK) {
+ xas->xa_offset = xas->xa_node->offset;
+ xas->xa_node = xas->xa_node->parent;
+ if (!xas->xa_node)
+ break;
+ continue;
+ }
+ curr = xa_entry_locked(xas->xa, xas->xa_node, ++xas->xa_offset);
+ if (xa_is_sibling(curr))
+ continue;
+ while (xa_is_node(curr)) {
+ xas->xa_node = xa_to_node(curr);
+ xas->xa_offset = 0;
+ curr = xa_entry_locked(xas->xa, xas->xa_node, 0);
+ }
+ if (curr)
+ return curr;
+ }
+ xas->xa_offset -= xas->xa_sibs;
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(xas_next_conflict);
+
/**
* xa_init_flags() - Initialise an empty XArray with flags.
* @xa: XArray.
--
2.17.1
next prev parent reply other threads:[~2018-06-17 1:59 UTC|newest]
Thread overview: 90+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-06-17 1:59 [PATCH v14 00/74] Convert page cache to XArray Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 01/74] Update email address Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 02/74] radix tree test suite: Enable ubsan Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 03/74] dax: Fix use of zero page Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 04/74] xarray: Replace exceptional entries Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 05/74] xarray: Change definition of sibling entries Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 06/74] xarray: Add definition of struct xarray Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 07/74] xarray: Define struct xa_node Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 08/74] xarray: Add documentation Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 09/74] xarray: Add XArray load operation Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 10/74] xarray: Add XArray tags Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 11/74] xarray: Add XArray unconditional store operations Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 12/74] xarray: Add XArray conditional " Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 13/74] xarray: Add XArray iterators Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 14/74] xarray: Extract entries from an XArray Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 15/74] xarray: Destroy " Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 16/74] xarray: Step through " Matthew Wilcox
2018-06-17 1:59 ` Matthew Wilcox [this message]
2018-06-17 1:59 ` [PATCH v14 18/74] xarray: Add xas_create_range Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 19/74] xarray: Add MAINTAINERS entry Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 20/74] page cache: Rearrange address_space Matthew Wilcox
2018-06-17 1:59 ` [PATCH v14 21/74] page cache: Convert hole search to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 22/74] page cache: Add and replace pages using the XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 23/74] page cache: Convert page deletion to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 24/74] page cache: Convert find_get_entry " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 25/74] page cache: Convert find_get_entries " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 26/74] page cache: Convert find_get_pages_range " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 27/74] page cache: Convert find_get_pages_contig " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 28/74] page cache; Convert find_get_pages_range_tag " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 29/74] page cache: Convert find_get_entries_tag " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 30/74] page cache: Convert filemap_map_pages " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 31/74] radix tree test suite: Convert regression1 " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 32/74] page cache: Convert delete_batch " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 33/74] page cache: Remove stray radix comment Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 34/74] page cache: Convert filemap_range_has_page to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 35/74] mm: Convert page-writeback " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 36/74] mm: Convert workingset " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 37/74] mm: Convert truncate " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 38/74] mm: Convert add_to_swap_cache " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 39/74] mm: Convert delete_from_swap_cache " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 40/74] mm: Convert __do_page_cache_readahead " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 41/74] mm: Convert page migration " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 42/74] mm: Convert huge_memory " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 43/74] mm: Convert collapse_shmem " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 44/74] mm: Convert khugepaged_scan_shmem " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 45/74] mm: Convert is_page_cache_freeable " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 46/74] pagevec: Use xa_tag_t Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 47/74] shmem: Convert shmem_radix_tree_replace to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 48/74] shmem: Convert shmem_confirm_swap " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 49/74] shmem: Convert find_swap_entry " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 50/74] shmem: Convert shmem_add_to_page_cache " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 51/74] shmem: Convert shmem_alloc_hugepage " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 52/74] shmem: Convert shmem_free_swap " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 53/74] shmem: Convert shmem_partial_swap_usage " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 54/74] memfd: Convert memfd_wait_for_pins " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 55/74] memfd: Convert memfd_tag_pins " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 56/74] shmem: Comment fixups Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 57/74] btrfs: Convert page cache to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 58/74] fs: Convert buffer " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 59/74] fs: Convert writeback " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 60/74] nilfs2: Convert " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 61/74] f2fs: " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 62/74] dax: Rename some functions Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 63/74] dax: Hash on XArray instead of mapping Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 64/74] dax: Convert dax_insert_pfn_mkwrite to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 65/74] dax: Convert dax_layout_busy_page " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 66/74] dax: Convert __dax_invalidate_entry " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 67/74] dax: Convert dax writeback " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 68/74] dax: Convert dax_lock_page " Matthew Wilcox
2018-06-29 17:30 ` Ross Zwisler
2018-07-06 11:54 ` [PATCH] fs/dax: remove unused function Anders Roxell
2018-07-06 13:04 ` [PATCH v14 68/74] dax: Convert dax_lock_page to XArray Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 69/74] dax: Convert page fault handlers " Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 70/74] page cache: Finish XArray conversion Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 71/74] radix tree: Remove radix_tree_update_node_t Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 72/74] radix tree: Remove split/join code Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 73/74] radix tree: Remove radix_tree_maybe_preload_order Matthew Wilcox
2018-06-17 2:00 ` [PATCH v14 74/74] radix tree: Remove radix_tree_clear_tags Matthew Wilcox
2018-06-19 3:12 ` [PATCH v14 00/74] Convert page cache to XArray Ross Zwisler
2018-06-19 9:22 ` Matthew Wilcox
2018-06-19 16:40 ` Ross Zwisler
2018-06-19 17:16 ` Matthew Wilcox
2018-06-27 11:05 ` Matthew Wilcox
2018-06-27 19:44 ` Ross Zwisler
2018-06-28 8:39 ` Matthew Wilcox
2018-06-28 16:30 ` Ross Zwisler
2018-07-25 21:03 ` Matthew Wilcox
2018-07-25 21:12 ` Ross Zwisler
2018-07-27 17:20 ` Ross Zwisler
2018-07-30 15:43 ` Matthew Wilcox
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