[Cluster-devel] [gfs2 patch] gfs2: Dump nrpages for inodes and their glocks

[Bob Peterson <rpeterso@redhat.com>]

Hi,

This patch is based on an idea from Steve Whitehouse. The idea is
to dump the number of pages (both inode and its glock's address
space) in the glock dumps. To avoid adding any new locks, I
switch from calling i_size_read to using its constituant pieces,
namely, calling preempt_disable before gathering the values of
i_size and the new nrpages values, then I preempt_enable.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
---
 fs/gfs2/glops.c | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index f79ef9525e33..f60411707e88 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -470,14 +470,28 @@ static int inode_go_lock(struct gfs2_holder *gh)
 static void inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
 {
 	const struct gfs2_inode *ip = gl->gl_object;
+	const struct inode *inode;
+	const struct address_space *mapping = (const struct address_space *)
+		(gl + 1); /* Can't use gfs2_glock2aspace due to const */
+	unsigned long nrpages1, nrpages2;
+	loff_t i_size;
+
 	if (ip == NULL)
 		return;
-	gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu\n",
+
+	inode = &ip->i_inode;
+	preempt_disable();
+	i_size = inode->i_size;
+	nrpages1 = inode->i_data.nrpages;
+	nrpages2 = mapping->nrpages;
+	preempt_enable();
+
+	gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu p:%lu/%lu\n",
 		  (unsigned long long)ip->i_no_formal_ino,
 		  (unsigned long long)ip->i_no_addr,
 		  IF2DT(ip->i_inode.i_mode), ip->i_flags,
 		  (unsigned int)ip->i_diskflags,
-		  (unsigned long long)i_size_read(&ip->i_inode));
+		  (unsigned long long)i_size, nrpages1, nrpages2);
 }
 
 /**