From: "Darrick J. Wong" <darrick.wong@oracle.com>
To: david@fromorbit.com, darrick.wong@oracle.com
Cc: linux-fsdevel@vger.kernel.org, vishal.l.verma@intel.com,
bfoster@redhat.com, xfs@oss.sgi.com
Subject: [PATCH 09/47] xfs: introduce interval queries on btrees
Date: Wed, 20 Jul 2016 21:56:59 -0700 [thread overview]
Message-ID: <146907701913.25461.16492865819245768513.stgit@birch.djwong.org> (raw)
In-Reply-To: <146907695530.25461.3225785294902719773.stgit@birch.djwong.org>
Create a function to enable querying of btree records mapping to a
range of keys. This will be used in subsequent patches to allow
querying the reverse mapping btree to find the extents mapped to a
range of physical blocks, though the generic code can be used for
any range query.
v2: add some shortcuts so that we can jump out of processing once
we know there won't be any more records to find.
v3: document the range query algorithm, refactor the pop-up code,
fix the diff_two_keys usage.
v4: The overlapped query range function should use the btree get_block
helper because the root block could be an inode, in which case
bc_bufs[nlevels-1] will be NULL. Refactor the key calculations
so that we can return -EINVAL if low > high.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
fs/xfs/libxfs/xfs_btree.c | 264 +++++++++++++++++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_btree.h | 22 +++-
fs/xfs/xfs_trace.h | 1
3 files changed, 282 insertions(+), 5 deletions(-)
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 1881536..3780128 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -4522,3 +4522,267 @@ xfs_btree_compute_maxlevels(
maxblocks = (maxblocks + limits[1] - 1) / limits[1];
return level;
}
+
+/*
+ * Query a regular btree for all records overlapping a given interval.
+ * Start with a LE lookup of the key of low_rec and return all records
+ * until we find a record with a key greater than the key of high_rec.
+ */
+STATIC int
+xfs_btree_simple_query_range(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *low_key,
+ union xfs_btree_key *high_key,
+ xfs_btree_query_range_fn fn,
+ void *priv)
+{
+ union xfs_btree_rec *recp;
+ union xfs_btree_key rec_key;
+ __int64_t diff;
+ int stat;
+ bool firstrec = true;
+ int error;
+
+ ASSERT(cur->bc_ops->init_high_key_from_rec);
+ ASSERT(cur->bc_ops->diff_two_keys);
+
+ /*
+ * Find the leftmost record. The btree cursor must be set
+ * to the low record used to generate low_key.
+ */
+ stat = 0;
+ error = xfs_btree_lookup(cur, XFS_LOOKUP_LE, &stat);
+ if (error)
+ goto out;
+
+ while (stat) {
+ /* Find the record. */
+ error = xfs_btree_get_rec(cur, &recp, &stat);
+ if (error || !stat)
+ break;
+ cur->bc_ops->init_high_key_from_rec(&rec_key, recp);
+
+ /* Skip if high_key(rec) < low_key. */
+ if (firstrec) {
+ firstrec = false;
+ diff = cur->bc_ops->diff_two_keys(cur, low_key,
+ &rec_key);
+ if (diff > 0)
+ goto advloop;
+ }
+
+ /* Stop if high_key < low_key(rec). */
+ diff = cur->bc_ops->diff_two_keys(cur, &rec_key, high_key);
+ if (diff > 0)
+ break;
+
+ /* Callback */
+ error = fn(cur, recp, priv);
+ if (error < 0 || error == XFS_BTREE_QUERY_RANGE_ABORT)
+ break;
+
+advloop:
+ /* Move on to the next record. */
+ error = xfs_btree_increment(cur, 0, &stat);
+ if (error)
+ break;
+ }
+
+out:
+ return error;
+}
+
+/*
+ * Query an overlapped interval btree for all records overlapping a given
+ * interval. This function roughly follows the algorithm given in
+ * "Interval Trees" of _Introduction to Algorithms_, which is section
+ * 14.3 in the 2nd and 3rd editions.
+ *
+ * First, generate keys for the low and high records passed in.
+ *
+ * For any leaf node, generate the high and low keys for the record.
+ * If the record keys overlap with the query low/high keys, pass the
+ * record to the function iterator.
+ *
+ * For any internal node, compare the low and high keys of each
+ * pointer against the query low/high keys. If there's an overlap,
+ * follow the pointer.
+ *
+ * As an optimization, we stop scanning a block when we find a low key
+ * that is greater than the query's high key.
+ */
+STATIC int
+xfs_btree_overlapped_query_range(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_key *low_key,
+ union xfs_btree_key *high_key,
+ xfs_btree_query_range_fn fn,
+ void *priv)
+{
+ union xfs_btree_ptr ptr;
+ union xfs_btree_ptr *pp;
+ union xfs_btree_key rec_key;
+ union xfs_btree_key rec_hkey;
+ union xfs_btree_key *lkp;
+ union xfs_btree_key *hkp;
+ union xfs_btree_rec *recp;
+ struct xfs_btree_block *block;
+ __int64_t ldiff;
+ __int64_t hdiff;
+ int level;
+ struct xfs_buf *bp;
+ int i;
+ int error;
+
+ /* Load the root of the btree. */
+ level = cur->bc_nlevels - 1;
+ cur->bc_ops->init_ptr_from_cur(cur, &ptr);
+ error = xfs_btree_lookup_get_block(cur, level, &ptr, &block);
+ if (error)
+ return error;
+ xfs_btree_get_block(cur, level, &bp);
+ trace_xfs_btree_overlapped_query_range(cur, level, bp);
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto out;
+#endif
+ cur->bc_ptrs[level] = 1;
+
+ while (level < cur->bc_nlevels) {
+ block = xfs_btree_get_block(cur, level, &bp);
+
+ /* End of node, pop back towards the root. */
+ if (cur->bc_ptrs[level] > be16_to_cpu(block->bb_numrecs)) {
+pop_up:
+ if (level < cur->bc_nlevels - 1)
+ cur->bc_ptrs[level + 1]++;
+ level++;
+ continue;
+ }
+
+ if (level == 0) {
+ /* Handle a leaf node. */
+ recp = xfs_btree_rec_addr(cur, cur->bc_ptrs[0], block);
+
+ cur->bc_ops->init_high_key_from_rec(&rec_hkey, recp);
+ ldiff = cur->bc_ops->diff_two_keys(cur, &rec_hkey,
+ low_key);
+
+ cur->bc_ops->init_key_from_rec(&rec_key, recp);
+ hdiff = cur->bc_ops->diff_two_keys(cur, high_key,
+ &rec_key);
+
+ /*
+ * If (record's high key >= query's low key) and
+ * (query's high key >= record's low key), then
+ * this record overlaps the query range; callback.
+ */
+ if (ldiff >= 0 && hdiff >= 0) {
+ error = fn(cur, recp, priv);
+ if (error < 0 ||
+ error == XFS_BTREE_QUERY_RANGE_ABORT)
+ break;
+ } else if (hdiff < 0) {
+ /* Record is larger than high key; pop. */
+ goto pop_up;
+ }
+ cur->bc_ptrs[level]++;
+ continue;
+ }
+
+ /* Handle an internal node. */
+ lkp = xfs_btree_key_addr(cur, cur->bc_ptrs[level], block);
+ hkp = xfs_btree_high_key_addr(cur, cur->bc_ptrs[level], block);
+ pp = xfs_btree_ptr_addr(cur, cur->bc_ptrs[level], block);
+
+ ldiff = cur->bc_ops->diff_two_keys(cur, hkp, low_key);
+ hdiff = cur->bc_ops->diff_two_keys(cur, high_key, lkp);
+
+ /*
+ * If (pointer's high key >= query's low key) and
+ * (query's high key >= pointer's low key), then
+ * this record overlaps the query range; follow pointer.
+ */
+ if (ldiff >= 0 && hdiff >= 0) {
+ level--;
+ error = xfs_btree_lookup_get_block(cur, level, pp,
+ &block);
+ if (error)
+ goto out;
+ xfs_btree_get_block(cur, level, &bp);
+ trace_xfs_btree_overlapped_query_range(cur, level, bp);
+#ifdef DEBUG
+ error = xfs_btree_check_block(cur, block, level, bp);
+ if (error)
+ goto out;
+#endif
+ cur->bc_ptrs[level] = 1;
+ continue;
+ } else if (hdiff < 0) {
+ /* The low key is larger than the upper range; pop. */
+ goto pop_up;
+ }
+ cur->bc_ptrs[level]++;
+ }
+
+out:
+ /*
+ * If we don't end this function with the cursor pointing at a record
+ * block, a subsequent non-error cursor deletion will not release
+ * node-level buffers, causing a buffer leak. This is quite possible
+ * with a zero-results range query, so release the buffers if we
+ * failed to return any results.
+ */
+ if (cur->bc_bufs[0] == NULL) {
+ for (i = 0; i < cur->bc_nlevels; i++) {
+ if (cur->bc_bufs[i]) {
+ xfs_trans_brelse(cur->bc_tp, cur->bc_bufs[i]);
+ cur->bc_bufs[i] = NULL;
+ cur->bc_ptrs[i] = 0;
+ cur->bc_ra[i] = 0;
+ }
+ }
+ }
+
+ return error;
+}
+
+/*
+ * Query a btree for all records overlapping a given interval of keys. The
+ * supplied function will be called with each record found; return one of the
+ * XFS_BTREE_QUERY_RANGE_{CONTINUE,ABORT} values or the usual negative error
+ * code. This function returns XFS_BTREE_QUERY_RANGE_ABORT, zero, or a
+ * negative error code.
+ */
+int
+xfs_btree_query_range(
+ struct xfs_btree_cur *cur,
+ union xfs_btree_irec *low_rec,
+ union xfs_btree_irec *high_rec,
+ xfs_btree_query_range_fn fn,
+ void *priv)
+{
+ union xfs_btree_rec rec;
+ union xfs_btree_key low_key;
+ union xfs_btree_key high_key;
+
+ /* Find the keys of both ends of the interval. */
+ cur->bc_rec = *high_rec;
+ cur->bc_ops->init_rec_from_cur(cur, &rec);
+ cur->bc_ops->init_key_from_rec(&high_key, &rec);
+
+ cur->bc_rec = *low_rec;
+ cur->bc_ops->init_rec_from_cur(cur, &rec);
+ cur->bc_ops->init_key_from_rec(&low_key, &rec);
+
+ /* Enforce low key < high key. */
+ if (cur->bc_ops->diff_two_keys(cur, &low_key, &high_key) > 0)
+ return -EINVAL;
+
+ if (!(cur->bc_flags & XFS_BTREE_OVERLAPPING))
+ return xfs_btree_simple_query_range(cur, &low_key,
+ &high_key, fn, priv);
+ return xfs_btree_overlapped_query_range(cur, &low_key, &high_key,
+ fn, priv);
+}
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 3645d91..4b1c04c 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -227,6 +227,12 @@ struct xfs_btree_ops {
#define LASTREC_DELREC 2
+union xfs_btree_irec {
+ struct xfs_alloc_rec_incore a;
+ struct xfs_bmbt_irec b;
+ struct xfs_inobt_rec_incore i;
+};
+
/*
* Btree cursor structure.
* This collects all information needed by the btree code in one place.
@@ -237,11 +243,7 @@ typedef struct xfs_btree_cur
struct xfs_mount *bc_mp; /* file system mount struct */
const struct xfs_btree_ops *bc_ops;
uint bc_flags; /* btree features - below */
- union {
- xfs_alloc_rec_incore_t a;
- xfs_bmbt_irec_t b;
- xfs_inobt_rec_incore_t i;
- } bc_rec; /* current insert/search record value */
+ union xfs_btree_irec bc_rec; /* current insert/search record value */
struct xfs_buf *bc_bufs[XFS_BTREE_MAXLEVELS]; /* buf ptr per level */
int bc_ptrs[XFS_BTREE_MAXLEVELS]; /* key/record # */
__uint8_t bc_ra[XFS_BTREE_MAXLEVELS]; /* readahead bits */
@@ -524,4 +526,14 @@ void xfs_btree_get_node_keys_overlapped(struct xfs_btree_cur *cur,
struct xfs_btree_block *block, union xfs_btree_key *key);
int xfs_btree_update_keys_overlapped(struct xfs_btree_cur *cur, int level);
+/* return codes */
+#define XFS_BTREE_QUERY_RANGE_CONTINUE 0 /* keep iterating */
+#define XFS_BTREE_QUERY_RANGE_ABORT 1 /* stop iterating */
+typedef int (*xfs_btree_query_range_fn)(struct xfs_btree_cur *cur,
+ union xfs_btree_rec *rec, void *priv);
+
+int xfs_btree_query_range(struct xfs_btree_cur *cur,
+ union xfs_btree_irec *low_rec, union xfs_btree_irec *high_rec,
+ xfs_btree_query_range_fn fn, void *priv);
+
#endif /* __XFS_BTREE_H__ */
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 8fb59e6..a586268 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -2220,6 +2220,7 @@ DEFINE_EVENT(xfs_btree_cur_class, name, \
TP_PROTO(struct xfs_btree_cur *cur, int level, struct xfs_buf *bp), \
TP_ARGS(cur, level, bp))
DEFINE_BTREE_CUR_EVENT(xfs_btree_updkeys);
+DEFINE_BTREE_CUR_EVENT(xfs_btree_overlapped_query_range);
#endif /* _TRACE_XFS_H */
next prev parent reply other threads:[~2016-07-21 4:57 UTC|newest]
Thread overview: 121+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-21 4:55 [PATCH v7 00/47] xfs: add reverse mapping support Darrick J. Wong
2016-07-21 4:56 ` [PATCH 01/47] vfs: fix return type of ioctl_file_dedupe_range Darrick J. Wong
2016-08-01 6:33 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 02/47] vfs: support FS_XFLAG_REFLINK and FS_XFLAG_COWEXTSIZE Darrick J. Wong
2016-08-01 6:33 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 03/47] xfs: fix attr shortform structure alignment on cris Darrick J. Wong
2016-07-26 16:36 ` Brian Foster
2016-08-01 6:34 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 04/47] xfs: fix locking of the rt bitmap/summary inodes Darrick J. Wong
2016-07-26 16:36 ` Brian Foster
2016-07-28 18:58 ` Darrick J. Wong
2016-08-01 6:34 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 05/47] xfs: set *stat=1 after iroot realloc Darrick J. Wong
2016-07-26 16:36 ` Brian Foster
2016-08-01 6:35 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 06/47] xfs: during btree split, save new block key & ptr for future insertion Darrick J. Wong
2016-07-26 16:36 ` Brian Foster
2016-08-01 6:37 ` Christoph Hellwig
2016-07-21 4:56 ` [PATCH 07/47] xfs: add function pointers for get/update keys to the btree Darrick J. Wong
2016-07-26 19:09 ` Brian Foster
2016-07-28 19:13 ` Darrick J. Wong
2016-07-28 19:46 ` [PATCH v2 " Darrick J. Wong
2016-08-01 15:57 ` Brian Foster
2016-08-01 17:54 ` Darrick J. Wong
2016-08-01 6:39 ` [PATCH " Christoph Hellwig
2016-08-01 17:33 ` Darrick J. Wong
2016-08-02 12:23 ` Christoph Hellwig
2016-08-03 0:12 ` Darrick J. Wong
2016-07-21 4:56 ` [PATCH 08/47] xfs: support btrees with overlapping intervals for keys Darrick J. Wong
2016-08-01 6:48 ` Christoph Hellwig
2016-08-01 19:11 ` Darrick J. Wong
2016-08-02 12:03 ` Christoph Hellwig
2016-08-03 3:29 ` Darrick J. Wong
2016-08-02 14:04 ` Brian Foster
2016-08-03 1:06 ` Dave Chinner
2016-08-01 17:47 ` Brian Foster
2016-08-01 19:18 ` Darrick J. Wong
2016-07-21 4:56 ` Darrick J. Wong [this message]
2016-08-01 8:00 ` [PATCH 09/47] xfs: introduce interval queries on btrees Christoph Hellwig
2016-07-21 4:57 ` [PATCH 10/47] xfs: refactor btree owner change into a separate visit-blocks function Darrick J. Wong
2016-08-01 6:50 ` Christoph Hellwig
2016-07-21 4:57 ` [PATCH 11/47] xfs: move deferred operations into a separate file Darrick J. Wong
2016-08-01 7:08 ` Christoph Hellwig
2016-08-01 8:02 ` Christoph Hellwig
2016-08-02 22:39 ` Dave Chinner
2016-08-03 9:16 ` Christoph Hellwig
2016-08-03 22:57 ` Dave Chinner
2016-08-04 16:00 ` Christoph Hellwig
2016-08-04 23:44 ` Dave Chinner
2016-08-02 17:30 ` Brian Foster
2016-07-21 4:57 ` [PATCH 12/47] xfs: add tracepoints for the deferred ops mechanism Darrick J. Wong
2016-07-21 4:57 ` [PATCH 13/47] xfs: clean up typedef usage in the EFI/EFD handling code Darrick J. Wong
2016-08-01 7:09 ` Christoph Hellwig
2016-07-21 4:57 ` [PATCH 14/47] xfs: enable the xfs_defer mechanism to process extents to free Darrick J. Wong
2016-08-01 7:09 ` Christoph Hellwig
2016-08-02 17:30 ` Brian Foster
2016-07-21 4:57 ` [PATCH 15/47] xfs: rework xfs_bmap_free callers to use xfs_defer_ops Darrick J. Wong
2016-08-02 17:30 ` Brian Foster
2016-07-21 4:57 ` [PATCH 16/47] xfs: change xfs_bmap_{finish, cancel, init, free} -> xfs_defer_* Darrick J. Wong
2016-08-02 17:30 ` Brian Foster
2016-08-02 20:47 ` Darrick J. Wong
2016-07-21 4:57 ` [PATCH 17/47] xfs: rename flist/free_list to dfops Darrick J. Wong
2016-08-02 17:30 ` Brian Foster
2016-07-21 4:58 ` [PATCH 18/47] xfs: refactor redo intent item processing Darrick J. Wong
2016-08-01 8:10 ` Christoph Hellwig
2016-08-02 20:35 ` Darrick J. Wong
2016-08-02 18:47 ` Brian Foster
2016-07-21 4:58 ` [PATCH 19/47] xfs: add tracepoints and error injection for deferred extent freeing Darrick J. Wong
2016-08-02 18:48 ` Brian Foster
2016-08-02 20:24 ` Darrick J. Wong
2016-08-02 21:38 ` Brian Foster
2016-08-02 22:43 ` Darrick J. Wong
2016-07-21 4:58 ` [PATCH 20/47] xfs: increase XFS_BTREE_MAXLEVELS to fit the rmapbt Darrick J. Wong
2016-08-02 18:48 ` Brian Foster
2016-08-02 20:06 ` Darrick J. Wong
2016-08-02 21:38 ` Brian Foster
2016-07-21 4:58 ` [PATCH 21/47] xfs: introduce rmap btree definitions Darrick J. Wong
2016-07-21 4:58 ` [PATCH 22/47] xfs: add rmap btree stats infrastructure Darrick J. Wong
2016-07-21 4:58 ` [PATCH 23/47] xfs: rmap btree add more reserved blocks Darrick J. Wong
2016-07-21 4:58 ` [PATCH 24/47] xfs: add owner field to extent allocation and freeing Darrick J. Wong
2016-07-21 4:58 ` [PATCH 25/47] xfs: introduce rmap extent operation stubs Darrick J. Wong
2016-07-21 4:58 ` [PATCH 26/47] xfs: define the on-disk rmap btree format Darrick J. Wong
2016-07-21 4:59 ` [PATCH 27/47] xfs: add rmap btree growfs support Darrick J. Wong
2016-07-21 4:59 ` [PATCH 28/47] xfs: rmap btree transaction reservations Darrick J. Wong
2016-07-21 4:59 ` [PATCH 29/47] xfs: rmap btree requires more reserved free space Darrick J. Wong
2016-07-21 4:59 ` [PATCH 30/47] xfs: add rmap btree operations Darrick J. Wong
2016-07-21 4:59 ` [PATCH 31/47] xfs: support overlapping intervals in the rmap btree Darrick J. Wong
2016-07-21 4:59 ` [PATCH 32/47] xfs: teach rmapbt to support interval queries Darrick J. Wong
2016-07-21 4:59 ` [PATCH 33/47] xfs: add tracepoints for the rmap functions Darrick J. Wong
2016-07-21 4:59 ` [PATCH 34/47] xfs: add an extent to the rmap btree Darrick J. Wong
2016-07-21 4:59 ` [PATCH 35/47] xfs: remove an extent from " Darrick J. Wong
2016-07-21 5:00 ` [PATCH 36/47] xfs: convert unwritten status of reverse mappings Darrick J. Wong
2016-08-03 2:00 ` Dave Chinner
2016-07-21 5:00 ` [PATCH 37/47] xfs: add rmap btree insert and delete helpers Darrick J. Wong
2016-07-21 5:00 ` [PATCH 38/47] xfs: create rmap update intent log items Darrick J. Wong
2016-08-01 7:12 ` Christoph Hellwig
2016-08-01 18:08 ` Darrick J. Wong
2016-07-21 5:00 ` [PATCH 39/47] xfs: log rmap intent items Darrick J. Wong
2016-07-21 5:00 ` [PATCH 40/47] xfs: enable the xfs_defer mechanism to process rmaps to update Darrick J. Wong
2016-07-21 5:00 ` [PATCH 41/47] xfs: propagate bmap updates to rmapbt Darrick J. Wong
2016-07-21 5:00 ` [PATCH 42/47] xfs: add rmap btree geometry feature flag Darrick J. Wong
2016-07-21 5:00 ` [PATCH 43/47] xfs: add rmap btree block detection to log recovery Darrick J. Wong
2016-07-21 5:00 ` [PATCH 44/47] xfs: disable XFS_IOC_SWAPEXT when rmap btree is enabled Darrick J. Wong
2016-07-21 5:01 ` [PATCH 45/47] xfs: don't update rmapbt when fixing agfl Darrick J. Wong
2016-07-21 5:01 ` [PATCH 46/47] xfs: enable the rmap btree functionality Darrick J. Wong
2016-07-21 5:01 ` [PATCH 47/47] xfs: introduce the XFS_IOC_GETFSMAP ioctl Darrick J. Wong
2016-07-23 4:28 ` [PATCH v2 " Darrick J. Wong
2016-08-03 19:45 ` [PATCH v7 00/47] xfs: add reverse mapping support Mark Fasheh
2016-08-03 20:55 ` Darrick J. Wong
2016-08-04 0:58 ` Darrick J. Wong
2016-08-04 2:18 ` Mark Fasheh
2016-08-04 15:48 ` Darrick J. Wong
2016-08-04 23:50 ` Dave Chinner
2016-08-05 0:49 ` Darrick J. Wong
2016-08-05 7:01 ` Artem Bityutskiy
2016-08-05 7:22 ` Darrick J. Wong
2016-08-05 10:49 ` Dave Chinner
2016-08-05 11:57 ` Artem Bityutskiy
2016-08-05 22:26 ` Dave Chinner
2016-08-05 18:36 ` Mark Fasheh
2016-08-05 22:39 ` Dave Chinner
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=146907701913.25461.16492865819245768513.stgit@birch.djwong.org \
--to=darrick.wong@oracle.com \
--cc=bfoster@redhat.com \
--cc=david@fromorbit.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=vishal.l.verma@intel.com \
--cc=xfs@oss.sgi.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).