From: Matthew Wilcox <willy@infradead.org>
To: linux-mm@kvack.org, linux-fsdevel@vger.kernel.org
Cc: Matthew Wilcox <mawilcox@microsoft.com>, 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,
Oleg Drokin <oleg.drokin@intel.com>,
Andreas Dilger <andreas.dilger@intel.com>,
James Simmons <jsimmons@infradead.org>,
Mike Kravetz <mike.kravetz@oracle.com>
Subject: [PATCH v10 12/62] xarray: Add xa_extract
Date: Thu, 29 Mar 2018 20:41:55 -0700 [thread overview]
Message-ID: <20180330034245.10462-13-willy@infradead.org> (raw)
In-Reply-To: <20180330034245.10462-1-willy@infradead.org>
From: Matthew Wilcox <mawilcox@microsoft.com>
This function combines the functionality of radix_tree_gang_lookup() and
radix_tree_gang_lookup_tagged(). It extracts entries matching the
specified filter into a normal array.
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
---
include/linux/xarray.h | 2 ++
lib/xarray.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 82 insertions(+)
diff --git a/include/linux/xarray.h b/include/linux/xarray.h
index c8b3645c6760..864f16660785 100644
--- a/include/linux/xarray.h
+++ b/include/linux/xarray.h
@@ -227,6 +227,8 @@ void *xa_find(struct xarray *xa, unsigned long *index,
unsigned long max, xa_tag_t) __attribute__((nonnull(2)));
void *xa_find_after(struct xarray *xa, unsigned long *index,
unsigned long max, xa_tag_t) __attribute__((nonnull(2)));
+unsigned int xa_extract(struct xarray *, void **dst, unsigned long start,
+ unsigned long max, unsigned int n, xa_tag_t);
/**
* xa_init() - Initialise an empty XArray.
diff --git a/lib/xarray.c b/lib/xarray.c
index 73cf4c984c2d..77133bc5419f 100644
--- a/lib/xarray.c
+++ b/lib/xarray.c
@@ -1402,6 +1402,86 @@ void *xa_find_after(struct xarray *xa, unsigned long *indexp,
}
EXPORT_SYMBOL(xa_find_after);
+static unsigned int xas_extract_present(struct xa_state *xas, void **dst,
+ unsigned long max, unsigned int n)
+{
+ void *entry;
+ unsigned int i = 0;
+
+ rcu_read_lock();
+ xas_for_each(xas, entry, max) {
+ if (xas_retry(xas, entry))
+ continue;
+ dst[i++] = entry;
+ if (i == n)
+ break;
+ }
+ rcu_read_unlock();
+
+ return i;
+}
+
+static unsigned int xas_extract_tag(struct xa_state *xas, void **dst,
+ unsigned long max, unsigned int n, xa_tag_t tag)
+{
+ void *entry;
+ unsigned int i = 0;
+
+ rcu_read_lock();
+ xas_for_each_tag(xas, entry, max, tag) {
+ if (xas_retry(xas, entry))
+ continue;
+ dst[i++] = entry;
+ if (i == n)
+ break;
+ }
+ rcu_read_unlock();
+
+ return i;
+}
+
+/**
+ * xa_extract() - Copy selected entries from the XArray into a normal array.
+ * @xa: The source XArray to copy from.
+ * @dst: The buffer to copy entries into.
+ * @start: The first index in the XArray eligible to be selected.
+ * @max: The last index in the XArray eligible to be selected.
+ * @n: The maximum number of entries to copy.
+ * @filter: Selection criterion.
+ *
+ * Copies up to @n entries that match @filter from the XArray. The
+ * copied entries will have indices between @start and @max, inclusive.
+ *
+ * The @filter may be an XArray tag value, in which case entries which are
+ * tagged with that tag will be copied. It may also be %XA_PRESENT, in
+ * which case non-NULL entries will be copied.
+ *
+ * The entries returned may not represent a snapshot of the XArray at a
+ * moment in time. For example, if another thread stores to index 5, then
+ * index 10, calling xa_extract() may return the old contents of index 5
+ * and the new contents of index 10. Indices not modified while this
+ * function is running will not be skipped.
+ *
+ * If you need stronger guarantees, holding the xa_lock across calls to this
+ * function will prevent concurrent modification.
+ *
+ * Context: Any context. Takes and releases the RCU lock.
+ * Return: The number of entries copied.
+ */
+unsigned int xa_extract(struct xarray *xa, void **dst, unsigned long start,
+ unsigned long max, unsigned int n, xa_tag_t filter)
+{
+ XA_STATE(xas, xa, start);
+
+ if (!n)
+ return 0;
+
+ if ((__force unsigned int)filter < XA_MAX_TAGS)
+ return xas_extract_tag(&xas, dst, max, n, filter);
+ return xas_extract_present(&xas, dst, max, n);
+}
+EXPORT_SYMBOL(xa_extract);
+
#ifdef XA_DEBUG
void xa_dump_node(const struct xa_node *node)
{
--
2.16.2
next prev parent reply other threads:[~2018-03-30 3:42 UTC|newest]
Thread overview: 74+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-30 3:41 [PATCH v10 00/62] Convert page cache to XArray Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 01/62] page cache: Use xa_lock Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 02/62] xarray: Replace exceptional entries Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 03/62] xarray: Change definition of sibling entries Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 04/62] xarray: Add definition of struct xarray Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 05/62] xarray: Define struct xa_node Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 06/62] xarray: Add documentation Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 07/62] xarray: Add xa_load Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 08/62] xarray: Add xa_get_tag, xa_set_tag and xa_clear_tag Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 09/62] xarray: Add xa_store Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 10/62] xarray: Add xa_cmpxchg and xa_insert Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 11/62] xarray: Add xa_for_each Matthew Wilcox
2018-03-30 3:41 ` Matthew Wilcox [this message]
2018-03-30 3:41 ` [PATCH v10 13/62] xarray: Add xa_destroy Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 14/62] xarray: Add xas_next and xas_prev Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 15/62] xarray: Add xas_create_range Matthew Wilcox
2018-03-30 3:41 ` [PATCH v10 16/62] xarray: Add MAINTAINERS entry Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 17/62] page cache: Rearrange address_space Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 18/62] page cache: Convert hole search to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 19/62] page cache: Add and replace pages using the XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 20/62] page cache: Convert page deletion to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 21/62] page cache: Convert page cache lookups " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 22/62] page cache: Convert delete_batch " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 23/62] page cache: Remove stray radix comment Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 24/62] page cache: Convert filemap_range_has_page to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 25/62] mm: Convert page-writeback " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 26/62] mm: Convert workingset " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 27/62] mm: Convert truncate " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 28/62] mm: Convert add_to_swap_cache " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 29/62] mm: Convert delete_from_swap_cache " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 30/62] mm: Convert __do_page_cache_readahead " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 31/62] mm: Convert page migration " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 32/62] mm: Convert huge_memory " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 33/62] mm: Convert collapse_shmem " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 34/62] mm: Convert khugepaged_scan_shmem " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 35/62] pagevec: Use xa_tag_t Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 36/62] shmem: Convert replace to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 37/62] shmem: Convert shmem_confirm_swap " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 38/62] shmem: Convert find_swap_entry " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 39/62] shmem: Convert shmem_add_to_page_cache " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 40/62] shmem: Convert shmem_alloc_hugepage " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 41/62] shmem: Convert shmem_free_swap " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 42/62] shmem: Convert shmem_partial_swap_usage " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 43/62] memfd: Convert shmem_tag_pins " Matthew Wilcox
2018-03-31 0:05 ` Mike Kravetz
2018-03-31 2:11 ` Matthew Wilcox
2018-04-03 20:51 ` Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 44/62] memfd: Convert shmem_wait_for_pins " Matthew Wilcox
2018-03-31 0:07 ` Mike Kravetz
2018-03-30 3:42 ` [PATCH v10 45/62] shmem: Comment fixups Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 46/62] btrfs: Convert page cache to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 47/62] fs: Convert buffer " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 48/62] fs: Convert writeback " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 49/62] nilfs2: Convert " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 50/62] f2fs: " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 51/62] lustre: " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 52/62] dax: Fix use of zero page Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 53/62] dax: dax_insert_mapping_entry always succeeds Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 54/62] dax: Rename some functions Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 55/62] dax: Hash on XArray instead of mapping Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 56/62] dax: Convert dax_insert_pfn_mkwrite to XArray Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 57/62] dax: Convert dax_layout_busy_page " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 58/62] dax: Convert __dax_invalidate_entry " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 59/62] dax: Convert dax writeback " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 60/62] dax: Convert page fault handlers " Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 61/62] page cache: Finish XArray conversion Matthew Wilcox
2018-03-30 3:42 ` [PATCH v10 62/62] radix tree: Remove unused functions Matthew Wilcox
2018-04-04 16:35 ` [PATCH v10 00/62] Convert page cache to XArray Mike Kravetz
2018-04-05 3:52 ` Matthew Wilcox
2018-04-05 18:33 ` Mike Kravetz
2018-04-09 21:18 ` Goldwyn Rodrigues
2018-04-14 19:50 ` Matthew Wilcox
2018-04-14 19:58 ` Matthew Wilcox
2018-04-17 21:49 ` Goldwyn Rodrigues
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180330034245.10462-13-willy@infradead.org \
--to=willy@infradead.org \
--cc=andreas.dilger@intel.com \
--cc=hch@lst.de \
--cc=jack@suse.cz \
--cc=jaegeuk@kernel.org \
--cc=jlayton@redhat.com \
--cc=jsimmons@infradead.org \
--cc=konishi.ryusuke@lab.ntt.co.jp \
--cc=lczerner@redhat.com \
--cc=linux-f2fs-devel@lists.sourceforge.net \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-nilfs@vger.kernel.org \
--cc=mawilcox@microsoft.com \
--cc=mike.kravetz@oracle.com \
--cc=npiggin@gmail.com \
--cc=oleg.drokin@intel.com \
--cc=rgoldwyn@suse.com \
--cc=ross.zwisler@linux.intel.com \
--cc=yuchao0@huawei.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).