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-rw-r--r--Documentation/filesystems/caching/fscache.txt2
-rw-r--r--fs/fscache/internal.h3
-rw-r--r--fs/fscache/operation.c82
-rw-r--r--fs/fscache/page.c55
-rw-r--r--fs/fscache/stats.c12
5 files changed, 115 insertions, 39 deletions
diff --git a/Documentation/filesystems/caching/fscache.txt b/Documentation/filesystems/caching/fscache.txt
index b6c32c0..0a77868 100644
--- a/Documentation/filesystems/caching/fscache.txt
+++ b/Documentation/filesystems/caching/fscache.txt
@@ -250,6 +250,7 @@ proc files.
ok=N Number of successful alloc reqs
wt=N Number of alloc reqs that waited on lookup completion
nbf=N Number of alloc reqs rejected -ENOBUFS
+ int=N Number of alloc reqs aborted -ERESTARTSYS
ops=N Number of alloc reqs submitted
owt=N Number of alloc reqs waited for CPU time
Retrvls n=N Number of retrieval (read) requests seen
@@ -271,6 +272,7 @@ proc files.
Ops pend=N Number of times async ops added to pending queues
run=N Number of times async ops given CPU time
enq=N Number of times async ops queued for processing
+ can=N Number of async ops cancelled
dfr=N Number of async ops queued for deferred release
rel=N Number of async ops released
gc=N Number of deferred-release async ops garbage collected
diff --git a/fs/fscache/internal.h b/fs/fscache/internal.h
index b85cc89..50324ad 100644
--- a/fs/fscache/internal.h
+++ b/fs/fscache/internal.h
@@ -112,6 +112,7 @@ extern int fscache_submit_exclusive_op(struct fscache_object *,
struct fscache_operation *);
extern int fscache_submit_op(struct fscache_object *,
struct fscache_operation *);
+extern int fscache_cancel_op(struct fscache_operation *);
extern void fscache_abort_object(struct fscache_object *);
extern void fscache_start_operations(struct fscache_object *);
extern void fscache_operation_gc(struct work_struct *);
@@ -140,6 +141,7 @@ extern atomic_t fscache_n_op_enqueue;
extern atomic_t fscache_n_op_deferred_release;
extern atomic_t fscache_n_op_release;
extern atomic_t fscache_n_op_gc;
+extern atomic_t fscache_n_op_cancelled;
extern atomic_t fscache_n_attr_changed;
extern atomic_t fscache_n_attr_changed_ok;
@@ -151,6 +153,7 @@ extern atomic_t fscache_n_allocs;
extern atomic_t fscache_n_allocs_ok;
extern atomic_t fscache_n_allocs_wait;
extern atomic_t fscache_n_allocs_nobufs;
+extern atomic_t fscache_n_allocs_intr;
extern atomic_t fscache_n_alloc_ops;
extern atomic_t fscache_n_alloc_op_waits;
diff --git a/fs/fscache/operation.c b/fs/fscache/operation.c
index 09e43b6..296492e 100644
--- a/fs/fscache/operation.c
+++ b/fs/fscache/operation.c
@@ -34,32 +34,31 @@ void fscache_enqueue_operation(struct fscache_operation *op)
fscache_set_op_state(op, "EnQ");
+ ASSERT(list_empty(&op->pend_link));
ASSERT(op->processor != NULL);
ASSERTCMP(op->object->state, >=, FSCACHE_OBJECT_AVAILABLE);
ASSERTCMP(atomic_read(&op->usage), >, 0);
- if (list_empty(&op->pend_link)) {
- switch (op->flags & FSCACHE_OP_TYPE) {
- case FSCACHE_OP_FAST:
- _debug("queue fast");
- atomic_inc(&op->usage);
- if (!schedule_work(&op->fast_work))
- fscache_put_operation(op);
- break;
- case FSCACHE_OP_SLOW:
- _debug("queue slow");
- slow_work_enqueue(&op->slow_work);
- break;
- case FSCACHE_OP_MYTHREAD:
- _debug("queue for caller's attention");
- break;
- default:
- printk(KERN_ERR "FS-Cache: Unexpected op type %lx",
- op->flags);
- BUG();
- break;
- }
- fscache_stat(&fscache_n_op_enqueue);
+ fscache_stat(&fscache_n_op_enqueue);
+ switch (op->flags & FSCACHE_OP_TYPE) {
+ case FSCACHE_OP_FAST:
+ _debug("queue fast");
+ atomic_inc(&op->usage);
+ if (!schedule_work(&op->fast_work))
+ fscache_put_operation(op);
+ break;
+ case FSCACHE_OP_SLOW:
+ _debug("queue slow");
+ slow_work_enqueue(&op->slow_work);
+ break;
+ case FSCACHE_OP_MYTHREAD:
+ _debug("queue for caller's attention");
+ break;
+ default:
+ printk(KERN_ERR "FS-Cache: Unexpected op type %lx",
+ op->flags);
+ BUG();
+ break;
}
}
EXPORT_SYMBOL(fscache_enqueue_operation);
@@ -97,6 +96,7 @@ int fscache_submit_exclusive_op(struct fscache_object *object,
spin_lock(&object->lock);
ASSERTCMP(object->n_ops, >=, object->n_in_progress);
ASSERTCMP(object->n_ops, >=, object->n_exclusive);
+ ASSERT(list_empty(&op->pend_link));
ret = -ENOBUFS;
if (fscache_object_is_active(object)) {
@@ -202,6 +202,7 @@ int fscache_submit_op(struct fscache_object *object,
spin_lock(&object->lock);
ASSERTCMP(object->n_ops, >=, object->n_in_progress);
ASSERTCMP(object->n_ops, >=, object->n_exclusive);
+ ASSERT(list_empty(&op->pend_link));
ostate = object->state;
smp_rmb();
@@ -273,12 +274,7 @@ void fscache_start_operations(struct fscache_object *object)
stop = true;
}
list_del_init(&op->pend_link);
- object->n_in_progress++;
-
- if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
- wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
- if (op->processor)
- fscache_enqueue_operation(op);
+ fscache_run_op(object, op);
/* the pending queue was holding a ref on the object */
fscache_put_operation(op);
@@ -291,6 +287,36 @@ void fscache_start_operations(struct fscache_object *object)
}
/*
+ * cancel an operation that's pending on an object
+ */
+int fscache_cancel_op(struct fscache_operation *op)
+{
+ struct fscache_object *object = op->object;
+ int ret;
+
+ _enter("OBJ%x OP%x}", op->object->debug_id, op->debug_id);
+
+ spin_lock(&object->lock);
+
+ ret = -EBUSY;
+ if (!list_empty(&op->pend_link)) {
+ fscache_stat(&fscache_n_op_cancelled);
+ list_del_init(&op->pend_link);
+ object->n_ops--;
+ if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags))
+ object->n_exclusive--;
+ if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags))
+ wake_up_bit(&op->flags, FSCACHE_OP_WAITING);
+ fscache_put_operation(op);
+ ret = 0;
+ }
+
+ spin_unlock(&object->lock);
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
* release an operation
* - queues pending ops if this is the last in-progress op
*/
diff --git a/fs/fscache/page.c b/fs/fscache/page.c
index 250dfd3..e6f2e61 100644
--- a/fs/fscache/page.c
+++ b/fs/fscache/page.c
@@ -295,8 +295,20 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
if (test_bit(FSCACHE_OP_WAITING, &op->op.flags)) {
_debug(">>> WT");
fscache_stat(&fscache_n_retrieval_op_waits);
- wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
- fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ if (wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit_interruptible,
+ TASK_INTERRUPTIBLE) < 0) {
+ ret = fscache_cancel_op(&op->op);
+ if (ret == 0) {
+ ret = -ERESTARTSYS;
+ goto error;
+ }
+
+ /* it's been removed from the pending queue by another
+ * party, so we should get to run shortly */
+ wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ }
_debug("<<< GO");
}
@@ -313,6 +325,7 @@ int __fscache_read_or_alloc_page(struct fscache_cookie *cookie,
fscache_stat_d(&fscache_n_cop_read_or_alloc_page);
}
+error:
if (ret == -ENOMEM)
fscache_stat(&fscache_n_retrievals_nomem);
else if (ret == -ERESTARTSYS)
@@ -412,8 +425,20 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
if (test_bit(FSCACHE_OP_WAITING, &op->op.flags)) {
_debug(">>> WT");
fscache_stat(&fscache_n_retrieval_op_waits);
- wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
- fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ if (wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit_interruptible,
+ TASK_INTERRUPTIBLE) < 0) {
+ ret = fscache_cancel_op(&op->op);
+ if (ret == 0) {
+ ret = -ERESTARTSYS;
+ goto error;
+ }
+
+ /* it's been removed from the pending queue by another
+ * party, so we should get to run shortly */
+ wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ }
_debug("<<< GO");
}
@@ -430,6 +455,7 @@ int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie,
fscache_stat_d(&fscache_n_cop_read_or_alloc_pages);
}
+error:
if (ret == -ENOMEM)
fscache_stat(&fscache_n_retrievals_nomem);
else if (ret == -ERESTARTSYS)
@@ -505,8 +531,20 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
if (test_bit(FSCACHE_OP_WAITING, &op->op.flags)) {
_debug(">>> WT");
fscache_stat(&fscache_n_alloc_op_waits);
- wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
- fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ if (wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit_interruptible,
+ TASK_INTERRUPTIBLE) < 0) {
+ ret = fscache_cancel_op(&op->op);
+ if (ret == 0) {
+ ret = -ERESTARTSYS;
+ goto error;
+ }
+
+ /* it's been removed from the pending queue by another
+ * party, so we should get to run shortly */
+ wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING,
+ fscache_wait_bit, TASK_UNINTERRUPTIBLE);
+ }
_debug("<<< GO");
}
@@ -515,7 +553,10 @@ int __fscache_alloc_page(struct fscache_cookie *cookie,
ret = object->cache->ops->allocate_page(op, page, gfp);
fscache_stat_d(&fscache_n_cop_allocate_page);
- if (ret < 0)
+error:
+ if (ret == -ERESTARTSYS)
+ fscache_stat(&fscache_n_allocs_intr);
+ else if (ret < 0)
fscache_stat(&fscache_n_allocs_nobufs);
else
fscache_stat(&fscache_n_allocs_ok);
diff --git a/fs/fscache/stats.c b/fs/fscache/stats.c
index 20233fb..4c07439 100644
--- a/fs/fscache/stats.c
+++ b/fs/fscache/stats.c
@@ -25,6 +25,7 @@ atomic_t fscache_n_op_requeue;
atomic_t fscache_n_op_deferred_release;
atomic_t fscache_n_op_release;
atomic_t fscache_n_op_gc;
+atomic_t fscache_n_op_cancelled;
atomic_t fscache_n_attr_changed;
atomic_t fscache_n_attr_changed_ok;
@@ -36,6 +37,7 @@ atomic_t fscache_n_allocs;
atomic_t fscache_n_allocs_ok;
atomic_t fscache_n_allocs_wait;
atomic_t fscache_n_allocs_nobufs;
+atomic_t fscache_n_allocs_intr;
atomic_t fscache_n_alloc_ops;
atomic_t fscache_n_alloc_op_waits;
@@ -169,11 +171,12 @@ static int fscache_stats_show(struct seq_file *m, void *v)
atomic_read(&fscache_n_attr_changed_nomem),
atomic_read(&fscache_n_attr_changed_calls));
- seq_printf(m, "Allocs : n=%u ok=%u wt=%u nbf=%u\n",
+ seq_printf(m, "Allocs : n=%u ok=%u wt=%u nbf=%u int=%u\n",
atomic_read(&fscache_n_allocs),
atomic_read(&fscache_n_allocs_ok),
atomic_read(&fscache_n_allocs_wait),
- atomic_read(&fscache_n_allocs_nobufs));
+ atomic_read(&fscache_n_allocs_nobufs),
+ atomic_read(&fscache_n_allocs_intr));
seq_printf(m, "Allocs : ops=%u owt=%u\n",
atomic_read(&fscache_n_alloc_ops),
atomic_read(&fscache_n_alloc_op_waits));
@@ -201,10 +204,11 @@ static int fscache_stats_show(struct seq_file *m, void *v)
atomic_read(&fscache_n_store_ops),
atomic_read(&fscache_n_store_calls));
- seq_printf(m, "Ops : pend=%u run=%u enq=%u\n",
+ seq_printf(m, "Ops : pend=%u run=%u enq=%u can=%u\n",
atomic_read(&fscache_n_op_pend),
atomic_read(&fscache_n_op_run),
- atomic_read(&fscache_n_op_enqueue));
+ atomic_read(&fscache_n_op_enqueue),
+ atomic_read(&fscache_n_op_cancelled));
seq_printf(m, "Ops : dfr=%u rel=%u gc=%u\n",
atomic_read(&fscache_n_op_deferred_release),
atomic_read(&fscache_n_op_release),
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