fscache: Add a cookie debug ID and use that in traces

Add a cookie debug ID and use that in traces and in procfiles rather than
displaying the (hashed) pointer to the cookie.  This is easier to correlate
and we don't lose anything when interpreting oops output since that shows
unhashed addresses and registers that aren't comparable to the hashed
values.

Changes:

ver #2:
 - Fix the fscache_op tracepoint to handle a NULL cookie pointer.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
cc: linux-cachefs@redhat.com
Link: https://lore.kernel.org/r/158861210988.340223.11688464116498247790.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/159465769844.1376105.14119502774019865432.stgit@warthog.procyon.org.uk/
Link: https://lore.kernel.org/r/160588459097.3465195.1273313637721852165.stgit@warthog.procyon.org.uk/ # rfc
Link: https://lore.kernel.org/r/162431193544.2908479.17556704572948300790.stgit@warthog.procyon.org.uk/

1 files changed, 58 insertions, 58 deletions

diff --git a/include/trace/events/fscache.h b/include/trace/events/fscache.h
index d16fe6ed78a2..33d1fd5d0383 100644
--- a/include/trace/events/fscache.h
+++ b/include/trace/events/fscache.h
@@ -167,8 +167,8 @@ TRACE_EVENT(fscache_cookie,
 	    TP_ARGS(cookie, where, usage),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_cookie *,	parent		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		parent		)
 		    __field(enum fscache_cookie_trace,	where		)
 		    __field(int,			usage		)
 		    __field(int,			n_children	)
@@ -177,8 +177,8 @@ TRACE_EVENT(fscache_cookie,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie;
-		    __entry->parent	= cookie->parent;
+		    __entry->cookie	= cookie->debug_id;
+		    __entry->parent	= cookie->parent ? cookie->parent->debug_id : 0;
 		    __entry->where	= where;
 		    __entry->usage	= usage;
 		    __entry->n_children	= atomic_read(&cookie->n_children);
@@ -186,7 +186,7 @@ TRACE_EVENT(fscache_cookie,
 		    __entry->flags	= cookie->flags;
 			   ),
 
-	    TP_printk("%s c=%p u=%d p=%p Nc=%d Na=%d f=%02x",
+	    TP_printk("%s c=%08x u=%d p=%08x Nc=%d Na=%d f=%02x",
 		      __print_symbolic(__entry->where, fscache_cookie_traces),
 		      __entry->cookie, __entry->usage,
 		      __entry->parent, __entry->n_children, __entry->n_active,
@@ -199,17 +199,17 @@ TRACE_EVENT(fscache_netfs,
 	    TP_ARGS(netfs),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 		    __array(char,			name, 8		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= netfs->primary_index;
+		    __entry->cookie		= netfs->primary_index->debug_id;
 		    strncpy(__entry->name, netfs->name, 8);
 		    __entry->name[7]		= 0;
 			   ),
 
-	    TP_printk("c=%p n=%s",
+	    TP_printk("c=%08x n=%s",
 		      __entry->cookie, __entry->name)
 	    );
 
@@ -219,8 +219,8 @@ TRACE_EVENT(fscache_acquire,
 	    TP_ARGS(cookie),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_cookie *,	parent		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		parent		)
 		    __array(char,			name, 8		)
 		    __field(int,			p_usage		)
 		    __field(int,			p_n_children	)
@@ -228,8 +228,8 @@ TRACE_EVENT(fscache_acquire,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
-		    __entry->parent		= cookie->parent;
+		    __entry->cookie		= cookie->debug_id;
+		    __entry->parent		= cookie->parent->debug_id;
 		    __entry->p_usage		= atomic_read(&cookie->parent->usage);
 		    __entry->p_n_children	= atomic_read(&cookie->parent->n_children);
 		    __entry->p_flags		= cookie->parent->flags;
@@ -237,7 +237,7 @@ TRACE_EVENT(fscache_acquire,
 		    __entry->name[7]		= 0;
 			   ),
 
-	    TP_printk("c=%p p=%p pu=%d pc=%d pf=%02x n=%s",
+	    TP_printk("c=%08x p=%08x pu=%d pc=%d pf=%02x n=%s",
 		      __entry->cookie, __entry->parent, __entry->p_usage,
 		      __entry->p_n_children, __entry->p_flags, __entry->name)
 	    );
@@ -248,8 +248,8 @@ TRACE_EVENT(fscache_relinquish,
 	    TP_ARGS(cookie, retire),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_cookie *,	parent		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		parent		)
 		    __field(int,			usage		)
 		    __field(int,			n_children	)
 		    __field(int,			n_active	)
@@ -258,8 +258,8 @@ TRACE_EVENT(fscache_relinquish,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie;
-		    __entry->parent	= cookie->parent;
+		    __entry->cookie	= cookie->debug_id;
+		    __entry->parent	= cookie->parent->debug_id;
 		    __entry->usage	= atomic_read(&cookie->usage);
 		    __entry->n_children	= atomic_read(&cookie->n_children);
 		    __entry->n_active	= atomic_read(&cookie->n_active);
@@ -267,7 +267,7 @@ TRACE_EVENT(fscache_relinquish,
 		    __entry->retire	= retire;
 			   ),
 
-	    TP_printk("c=%p u=%d p=%p Nc=%d Na=%d f=%02x r=%u",
+	    TP_printk("c=%08x u=%d p=%08x Nc=%d Na=%d f=%02x r=%u",
 		      __entry->cookie, __entry->usage,
 		      __entry->parent, __entry->n_children, __entry->n_active,
 		      __entry->flags, __entry->retire)
@@ -279,7 +279,7 @@ TRACE_EVENT(fscache_enable,
 	    TP_ARGS(cookie),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 		    __field(int,			usage		)
 		    __field(int,			n_children	)
 		    __field(int,			n_active	)
@@ -287,14 +287,14 @@ TRACE_EVENT(fscache_enable,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie;
+		    __entry->cookie	= cookie->debug_id;
 		    __entry->usage	= atomic_read(&cookie->usage);
 		    __entry->n_children	= atomic_read(&cookie->n_children);
 		    __entry->n_active	= atomic_read(&cookie->n_active);
 		    __entry->flags	= cookie->flags;
 			   ),
 
-	    TP_printk("c=%p u=%d Nc=%d Na=%d f=%02x",
+	    TP_printk("c=%08x u=%d Nc=%d Na=%d f=%02x",
 		      __entry->cookie, __entry->usage,
 		      __entry->n_children, __entry->n_active, __entry->flags)
 	    );
@@ -305,7 +305,7 @@ TRACE_EVENT(fscache_disable,
 	    TP_ARGS(cookie),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 		    __field(int,			usage		)
 		    __field(int,			n_children	)
 		    __field(int,			n_active	)
@@ -313,14 +313,14 @@ TRACE_EVENT(fscache_disable,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie	= cookie;
+		    __entry->cookie	= cookie->debug_id;
 		    __entry->usage	= atomic_read(&cookie->usage);
 		    __entry->n_children	= atomic_read(&cookie->n_children);
 		    __entry->n_active	= atomic_read(&cookie->n_active);
 		    __entry->flags	= cookie->flags;
 			   ),
 
-	    TP_printk("c=%p u=%d Nc=%d Na=%d f=%02x",
+	    TP_printk("c=%08x u=%d Nc=%d Na=%d f=%02x",
 		      __entry->cookie, __entry->usage,
 		      __entry->n_children, __entry->n_active, __entry->flags)
 	    );
@@ -333,8 +333,8 @@ TRACE_EVENT(fscache_osm,
 	    TP_ARGS(object, state, wait, oob, event_num),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_object *,	object		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		object		)
 		    __array(char,			state, 8	)
 		    __field(bool,			wait		)
 		    __field(bool,			oob		)
@@ -342,15 +342,15 @@ TRACE_EVENT(fscache_osm,
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= object->cookie;
-		    __entry->object		= object;
+		    __entry->cookie		= object->cookie->debug_id;
+		    __entry->object		= object->debug_id;
 		    __entry->wait		= wait;
 		    __entry->oob		= oob;
 		    __entry->event_num		= event_num;
 		    memcpy(__entry->state, state->short_name, 8);
 			   ),
 
-	    TP_printk("c=%p o=%p %s %s%sev=%d",
+	    TP_printk("c=%08x o=%08d %s %s%sev=%d",
 		      __entry->cookie,
 		      __entry->object,
 		      __entry->state,
@@ -370,18 +370,18 @@ TRACE_EVENT(fscache_page,
 	    TP_ARGS(cookie, page, why),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 		    __field(pgoff_t,			page		)
 		    __field(enum fscache_page_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
+		    __entry->cookie		= cookie->debug_id;
 		    __entry->page		= page->index;
 		    __entry->why		= why;
 			   ),
 
-	    TP_printk("c=%p %s pg=%lx",
+	    TP_printk("c=%08x %s pg=%lx",
 		      __entry->cookie,
 		      __print_symbolic(__entry->why, fscache_page_traces),
 		      __entry->page)
@@ -394,20 +394,20 @@ TRACE_EVENT(fscache_check_page,
 	    TP_ARGS(cookie, page, val, n),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 		    __field(void *,			page		)
 		    __field(void *,			val		)
 		    __field(int,			n		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
+		    __entry->cookie		= cookie->debug_id;
 		    __entry->page		= page;
 		    __entry->val		= val;
 		    __entry->n			= n;
 			   ),
 
-	    TP_printk("c=%p pg=%p val=%p n=%d",
+	    TP_printk("c=%08x pg=%p val=%p n=%d",
 		      __entry->cookie, __entry->page, __entry->val, __entry->n)
 	    );
 
@@ -417,14 +417,14 @@ TRACE_EVENT(fscache_wake_cookie,
 	    TP_ARGS(cookie),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
+		    __entry->cookie		= cookie->debug_id;
 			   ),
 
-	    TP_printk("c=%p", __entry->cookie)
+	    TP_printk("c=%08x", __entry->cookie)
 	    );
 
 TRACE_EVENT(fscache_op,
@@ -434,18 +434,18 @@ TRACE_EVENT(fscache_op,
 	    TP_ARGS(cookie, op, why),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_operation *,	op		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		op		)
 		    __field(enum fscache_op_trace,	why		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
-		    __entry->op			= op;
+		    __entry->cookie		= cookie ? cookie->debug_id : 0;
+		    __entry->op			= op->debug_id;
 		    __entry->why		= why;
 			   ),
 
-	    TP_printk("c=%p op=%p %s",
+	    TP_printk("c=%08x op=%08x %s",
 		      __entry->cookie, __entry->op,
 		      __print_symbolic(__entry->why, fscache_op_traces))
 	    );
@@ -457,20 +457,20 @@ TRACE_EVENT(fscache_page_op,
 	    TP_ARGS(cookie, page, op, what),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		op		)
 		    __field(pgoff_t,			page		)
-		    __field(struct fscache_operation *,	op		)
 		    __field(enum fscache_page_op_trace,	what		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
+		    __entry->cookie		= cookie->debug_id;
 		    __entry->page		= page ? page->index : 0;
-		    __entry->op			= op;
+		    __entry->op			= op->debug_id;
 		    __entry->what		= what;
 			   ),
 
-	    TP_printk("c=%p %s pg=%lx op=%p",
+	    TP_printk("c=%08x %s pg=%lx op=%08x",
 		      __entry->cookie,
 		      __print_symbolic(__entry->what, fscache_page_op_traces),
 		      __entry->page, __entry->op)
@@ -483,20 +483,20 @@ TRACE_EVENT(fscache_wrote_page,
 	    TP_ARGS(cookie, page, op, ret),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		op		)
 		    __field(pgoff_t,			page		)
-		    __field(struct fscache_operation *,	op		)
 		    __field(int,			ret		)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
+		    __entry->cookie		= cookie->debug_id;
 		    __entry->page		= page->index;
-		    __entry->op			= op;
+		    __entry->op			= op->debug_id;
 		    __entry->ret		= ret;
 			   ),
 
-	    TP_printk("c=%p pg=%lx op=%p ret=%d",
+	    TP_printk("c=%08x pg=%lx op=%08x ret=%d",
 		      __entry->cookie, __entry->page, __entry->op, __entry->ret)
 	    );
 
@@ -507,22 +507,22 @@ TRACE_EVENT(fscache_gang_lookup,
 	    TP_ARGS(cookie, op, results, n, store_limit),
 
 	    TP_STRUCT__entry(
-		    __field(struct fscache_cookie *,	cookie		)
-		    __field(struct fscache_operation *,	op		)
+		    __field(unsigned int,		cookie		)
+		    __field(unsigned int,		op		)
 		    __field(pgoff_t,			results0	)
 		    __field(int,			n		)
 		    __field(pgoff_t,			store_limit	)
 			     ),
 
 	    TP_fast_assign(
-		    __entry->cookie		= cookie;
-		    __entry->op			= op;
+		    __entry->cookie		= cookie->debug_id;
+		    __entry->op			= op->debug_id;
 		    __entry->results0		= results[0] ? ((struct page *)results[0])->index : (pgoff_t)-1;
 		    __entry->n			= n;
 		    __entry->store_limit	= store_limit;
 			   ),
 
-	    TP_printk("c=%p op=%p r0=%lx n=%d sl=%lx",
+	    TP_printk("c=%08x op=%08x r0=%lx n=%d sl=%lx",
 		      __entry->cookie, __entry->op, __entry->results0, __entry->n,
 		      __entry->store_limit)
 	    );