FS-Cache: Annotate slow-work runqueue proc lines for FS-Cache work items

Annotate slow-work runqueue proc lines for FS-Cache work items.  Objects
include the object ID and the state.  Operations include the object ID, the
operation ID and the operation type and state.

Signed-off-by: David Howells <dhowells@redhat.com>

1 files changed, 29 insertions, 0 deletions

diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index f1a2857b2ff5..91bbe6f0377c 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -13,6 +13,7 @@
 
 #define FSCACHE_DEBUG_LEVEL OPERATION
 #include <linux/module.h>
+#include <linux/seq_file.h>
 #include "internal.h"
 
 atomic_t fscache_op_debug_id;
@@ -31,6 +32,8 @@ void fscache_enqueue_operation(struct fscache_operation *op)
         _enter("{OBJ%x OP%x,%u}",
                op->object->debug_id, op->debug_id, atomic_read(&op->usage));
 
+        fscache_set_op_state(op, "EnQ");
+
         ASSERT(op->processor != NULL);
         ASSERTCMP(op->object->state, >=, FSCACHE_OBJECT_AVAILABLE);
         ASSERTCMP(atomic_read(&op->usage), >, 0);
@@ -67,6 +70,8 @@ EXPORT_SYMBOL(fscache_enqueue_operation);
 static void fscache_run_op(struct fscache_object *object,
                            struct fscache_operation *op)
 {
+        fscache_set_op_state(op, "Run");
+
         object->n_in_progress++;
         if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
                 wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
@@ -87,6 +92,8 @@ int fscache_submit_exclusive_op(struct fscache_object *object,
 
         _enter("{OBJ%x OP%x},", object->debug_id, op->debug_id);
 
+        fscache_set_op_state(op, "SubmitX");
+
         spin_lock(&object->lock);
         ASSERTCMP(object->n_ops, >=, object->n_in_progress);
         ASSERTCMP(object->n_ops, >=, object->n_exclusive);
@@ -190,6 +197,8 @@ int fscache_submit_op(struct fscache_object *object,
 
         ASSERTCMP(atomic_read(&op->usage), >, 0);
 
+        fscache_set_op_state(op, "Submit");
+
         spin_lock(&object->lock);
         ASSERTCMP(object->n_ops, >=, object->n_in_progress);
         ASSERTCMP(object->n_ops, >=, object->n_exclusive);
@@ -298,6 +307,8 @@ void fscache_put_operation(struct fscache_operation *op)
         if (!atomic_dec_and_test(&op->usage))
                 return;
 
+        fscache_set_op_state(op, "Put");
+
         _debug("PUT OP");
         if (test_and_set_bit(FSCACHE_OP_DEAD, &op->flags))
                 BUG();
@@ -452,9 +463,27 @@ static void fscache_op_execute(struct slow_work *work)
         _leave("");
 }
 
+/*
+ * describe an operation for slow-work debugging
+ */
+#ifdef CONFIG_SLOW_WORK_PROC
+static void fscache_op_desc(struct slow_work *work, struct seq_file *m)
+{
+        struct fscache_operation *op =
+                container_of(work, struct fscache_operation, slow_work);
+
+        seq_printf(m, "FSC: OBJ%x OP%x: %s/%s fl=%lx",
+                   op->object->debug_id, op->debug_id,
+                   op->name, op->state, op->flags);
+}
+#endif
+
 const struct slow_work_ops fscache_op_slow_work_ops = {
         .owner          = THIS_MODULE,
         .get_ref        = fscache_op_get_ref,
         .put_ref        = fscache_op_put_ref,
         .execute        = fscache_op_execute,
+#ifdef CONFIG_SLOW_WORK_PROC
+        .desc           = fscache_op_desc,
+#endif
 };