[PATCH v2 02/21] netfs: Add the cache object ID to netfs_read/write tracepoints

[David Howells]

Add the cache object debug ID to netfs_read/write tracepoints to make
debugging easier as there's now a direct cross-reference with the
cachefiles tracepoints that only log that debug ID.

Signed-off-by: David Howells <dhowells at redhat.com>
cc: Paulo Alcantara <pc at manguebit.org>
cc: netfs at lists.linux.dev
cc: linux-fsdevel at vger.kernel.org
---
 fs/cachefiles/io.c           |  1 +
 fs/netfs/fscache_io.c        |  2 +-
 include/linux/netfs.h        |  3 ++-
 include/trace/events/netfs.h | 27 +++++++++++++++------------
 4 files changed, 19 insertions(+), 14 deletions(-)

diff --git a/fs/cachefiles/io.c b/fs/cachefiles/io.c
index 42265fdcc17e..7e32b1caf6fe 100644
--- a/fs/cachefiles/io.c
+++ b/fs/cachefiles/io.c
@@ -918,6 +918,7 @@ bool cachefiles_begin_operation(struct netfs_cache_resources *cres,
 			if (!cres->cache_priv2 && file)
 				cres->cache_priv2 = get_file(file);
 			spin_unlock(&object->lock);
+			cres->object_id = object->debug_id;
 			cres->cache_i_size = i_size_read(file_inode(file));
 			cres->dio_size = object->volume->cache->bsize;
 		}
diff --git a/fs/netfs/fscache_io.c b/fs/netfs/fscache_io.c
index 37f05b4d3469..fafa8c6bec57 100644
--- a/fs/netfs/fscache_io.c
+++ b/fs/netfs/fscache_io.c
@@ -79,7 +79,7 @@ static int fscache_begin_operation(struct netfs_cache_resources *cres,
 	cres->ops		= NULL;
 	cres->cache_priv	= cookie;
 	cres->cache_priv2	= NULL;
-	cres->debug_id		= cookie->debug_id;
+	cres->cookie_id		= cookie->debug_id;
 	cres->inval_counter	= cookie->inval_counter;
 
 	if (!fscache_begin_cookie_access(cookie, why)) {
diff --git a/include/linux/netfs.h b/include/linux/netfs.h
index a83a4ea86e2b..d175c63ff659 100644
--- a/include/linux/netfs.h
+++ b/include/linux/netfs.h
@@ -162,7 +162,8 @@ struct netfs_cache_resources {
 	void				*cache_priv;
 	void				*cache_priv2;
 	unsigned long long		cache_i_size;	/* Initial size of cache file */
-	unsigned int			debug_id;	/* Cookie debug ID */
+	unsigned int			cookie_id;	/* Cache cookie debug ID */
+	unsigned int			object_id;	/* Cache object debug ID */
 	unsigned int			inval_counter;	/* object->inval_counter at begin_op */
 	unsigned int			dio_size;	/* DIO block size */
 };
diff --git a/include/trace/events/netfs.h b/include/trace/events/netfs.h
index 83d161f8c726..63ed1d771bd8 100644
--- a/include/trace/events/netfs.h
+++ b/include/trace/events/netfs.h
@@ -311,6 +311,7 @@ TRACE_EVENT(netfs_read,
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		rreq)
 		    __field(unsigned int,		cookie)
+		    __field(unsigned int,		object)
 		    __field(loff_t,			i_size)
 		    __field(loff_t,			start)
 		    __field(size_t,			len)
@@ -320,7 +321,8 @@ TRACE_EVENT(netfs_read,
 
 	    TP_fast_assign(
 		    __entry->rreq	= rreq->debug_id;
-		    __entry->cookie	= rreq->cache_resources.debug_id;
+		    __entry->cookie	= rreq->cache_resources.cookie_id;
+		    __entry->object	= rreq->cache_resources.object_id;
 		    __entry->i_size	= rreq->i_size;
 		    __entry->start	= start;
 		    __entry->len	= len;
@@ -328,10 +330,10 @@ TRACE_EVENT(netfs_read,
 		    __entry->netfs_inode = rreq->inode->i_ino;
 			   ),
 
-	    TP_printk("R=%08x %s c=%08x ni=%llx s=%llx l=%zx sz=%llx",
+	    TP_printk("R=%08x %s c=%08x o=%08x ni=%llx s=%llx l=%zx sz=%llx",
 		      __entry->rreq,
 		      __print_symbolic(__entry->what, netfs_read_traces),
-		      __entry->cookie,
+		      __entry->cookie, __entry->object,
 		      __entry->netfs_inode,
 		      __entry->start, __entry->len, __entry->i_size)
 	    );
@@ -552,6 +554,7 @@ TRACE_EVENT(netfs_write,
 	    TP_STRUCT__entry(
 		    __field(unsigned int,		wreq)
 		    __field(unsigned int,		cookie)
+		    __field(unsigned int,		object)
 		    __field(unsigned int,		ino)
 		    __field(enum netfs_write_trace,	what)
 		    __field(unsigned long long,		start)
@@ -559,20 +562,19 @@ TRACE_EVENT(netfs_write,
 			     ),
 
 	    TP_fast_assign(
-		    struct netfs_inode *__ctx = netfs_inode(wreq->inode);
-		    struct fscache_cookie *__cookie = netfs_i_cookie(__ctx);
 		    __entry->wreq	= wreq->debug_id;
-		    __entry->cookie	= __cookie ? __cookie->debug_id : 0;
+		    __entry->cookie	= wreq->cache_resources.cookie_id;
+		    __entry->object	= wreq->cache_resources.object_id;
 		    __entry->ino	= wreq->inode->i_ino;
 		    __entry->what	= what;
 		    __entry->start	= wreq->start;
 		    __entry->len	= wreq->len;
 			   ),
 
-	    TP_printk("R=%08x %s c=%08x i=%x by=%llx-%llx",
+	    TP_printk("R=%08x %s c=%08x o=%08x i=%x by=%llx-%llx",
 		      __entry->wreq,
 		      __print_symbolic(__entry->what, netfs_write_traces),
-		      __entry->cookie,
+		      __entry->cookie, __entry->object,
 		      __entry->ino,
 		      __entry->start, __entry->start + __entry->len - 1)
 	    );
@@ -587,22 +589,23 @@ TRACE_EVENT(netfs_copy2cache,
 		    __field(unsigned int,		rreq)
 		    __field(unsigned int,		creq)
 		    __field(unsigned int,		cookie)
+		    __field(unsigned int,		object)
 		    __field(unsigned int,		ino)
 			     ),
 
 	    TP_fast_assign(
-		    struct netfs_inode *__ctx = netfs_inode(rreq->inode);
-		    struct fscache_cookie *__cookie = netfs_i_cookie(__ctx);
 		    __entry->rreq	= rreq->debug_id;
 		    __entry->creq	= creq->debug_id;
-		    __entry->cookie	= __cookie ? __cookie->debug_id : 0;
+		    __entry->cookie	= rreq->cache_resources.cookie_id;
+		    __entry->object	= rreq->cache_resources.object_id;
 		    __entry->ino	= rreq->inode->i_ino;
 			   ),
 
-	    TP_printk("R=%08x CR=%08x c=%08x i=%x ",
+	    TP_printk("R=%08x CR=%08x c=%08x o=%08x i=%x ",
 		      __entry->rreq,
 		      __entry->creq,
 		      __entry->cookie,
+		      __entry->object,
 		      __entry->ino)
 	    );