tracing: add flag output for kmem events

This patch changes the output for gfp_flags from being a simple hex value
to the actual names.

  gfp_flags=GFP_ATOMIC  instead of gfp_flags=00000020

And even

  gfp_flags=GFP_KERNEL instead of gfp_flags=000000d0

(Thanks to Frederic Weisbecker for pointing out that the first version
 had a bad order of GFP masks)

[ Impact: more human readable output from tracer ]

Acked-by: Eduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>

1 files changed, 45 insertions, 8 deletions

diff --git a/include/trace/events/kmem.h b/include/trace/events/kmem.h
index c22c42f980b5..9baba50d6512 100644
--- a/include/trace/events/kmem.h
+++ b/include/trace/events/kmem.h
@@ -7,6 +7,43 @@
 #undef TRACE_SYSTEM
 #define TRACE_SYSTEM kmem
 
+/*
+ * The order of these masks is important. Matching masks will be seen
+ * first and the left over flags will end up showing by themselves.
+ *
+ * For example, if we have GFP_KERNEL before GFP_USER we wil get:
+ *
+ *  GFP_KERNEL|GFP_HARDWALL
+ *
+ * Thus most bits set go first.
+ */
+#define show_gfp_flags(flags)                                           \
+        (flags) ? __print_flags(flags, "|",                             \
+        {(unsigned long)GFP_HIGHUSER_MOVABLE,   "GFP_HIGHUSER_MOVABLE"}, \
+        {(unsigned long)GFP_HIGHUSER,           "GFP_HIGHUSER"},        \
+        {(unsigned long)GFP_USER,               "GFP_USER"},            \
+        {(unsigned long)GFP_TEMPORARY,          "GFP_TEMPORARY"},       \
+        {(unsigned long)GFP_KERNEL,             "GFP_KERNEL"},          \
+        {(unsigned long)GFP_NOFS,               "GFP_NOFS"},            \
+        {(unsigned long)GFP_ATOMIC,             "GFP_ATOMIC"},          \
+        {(unsigned long)GFP_NOIO,               "GFP_NOIO"},            \
+        {(unsigned long)__GFP_HIGH,             "GFP_HIGH"},            \
+        {(unsigned long)__GFP_WAIT,             "GFP_WAIT"},            \
+        {(unsigned long)__GFP_IO,               "GFP_IO"},              \
+        {(unsigned long)__GFP_COLD,             "GFP_COLD"},            \
+        {(unsigned long)__GFP_NOWARN,           "GFP_NOWARN"},          \
+        {(unsigned long)__GFP_REPEAT,           "GFP_REPEAT"},          \
+        {(unsigned long)__GFP_NOFAIL,           "GFP_NOFAIL"},          \
+        {(unsigned long)__GFP_NORETRY,          "GFP_NORETRY"},         \
+        {(unsigned long)__GFP_COMP,             "GFP_COMP"},            \
+        {(unsigned long)__GFP_ZERO,             "GFP_ZERO"},            \
+        {(unsigned long)__GFP_NOMEMALLOC,       "GFP_NOMEMALLOC"},      \
+        {(unsigned long)__GFP_HARDWALL,         "GFP_HARDWALL"},        \
+        {(unsigned long)__GFP_THISNODE,         "GFP_THISNODE"},        \
+        {(unsigned long)__GFP_RECLAIMABLE,      "GFP_RECLAIMABLE"},     \
+        {(unsigned long)__GFP_MOVABLE,          "GFP_MOVABLE"}          \
+        ) : "GFP_NOWAIT"
+
 TRACE_EVENT(kmalloc,
 
         TP_PROTO(unsigned long call_site,
@@ -33,12 +70,12 @@ TRACE_EVENT(kmalloc,
                 __entry->gfp_flags      = gfp_flags;
         ),
 
-        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%08x",
+        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s",
                 __entry->call_site,
                 __entry->ptr,
                 __entry->bytes_req,
                 __entry->bytes_alloc,
-                __entry->gfp_flags)
+                show_gfp_flags(__entry->gfp_flags))
 );
 
 TRACE_EVENT(kmem_cache_alloc,
@@ -67,12 +104,12 @@ TRACE_EVENT(kmem_cache_alloc,
                 __entry->gfp_flags      = gfp_flags;
         ),
 
-        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%08x",
+        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s",
                 __entry->call_site,
                 __entry->ptr,
                 __entry->bytes_req,
                 __entry->bytes_alloc,
-                __entry->gfp_flags)
+                show_gfp_flags(__entry->gfp_flags))
 );
 
 TRACE_EVENT(kmalloc_node,
@@ -104,12 +141,12 @@ TRACE_EVENT(kmalloc_node,
                 __entry->node           = node;
         ),
 
-        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%08x node=%d",
+        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d",
                 __entry->call_site,
                 __entry->ptr,
                 __entry->bytes_req,
                 __entry->bytes_alloc,
-                __entry->gfp_flags,
+                show_gfp_flags(__entry->gfp_flags),
                 __entry->node)
 );
 
@@ -142,12 +179,12 @@ TRACE_EVENT(kmem_cache_alloc_node,
                 __entry->node           = node;
         ),
 
-        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%08x node=%d",
+        TP_printk("call_site=%lx ptr=%p bytes_req=%zu bytes_alloc=%zu gfp_flags=%s node=%d",
                 __entry->call_site,
                 __entry->ptr,
                 __entry->bytes_req,
                 __entry->bytes_alloc,
-                __entry->gfp_flags,
+                show_gfp_flags(__entry->gfp_flags),
                 __entry->node)
 );