#include <linux/linkage.h>
#include <linux/bitops.h>
#include <linux/lockdep.h>
+#include <linux/threads.h>
#include <asm/atomic.h>
struct workqueue_struct;
enum {
WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
- WORK_STRUCT_LINKED_BIT = 1, /* next work is linked to this one */
+ WORK_STRUCT_CWQ_BIT = 1, /* data points to cwq */
+ WORK_STRUCT_LINKED_BIT = 2, /* next work is linked to this one */
#ifdef CONFIG_DEBUG_OBJECTS_WORK
- WORK_STRUCT_STATIC_BIT = 2, /* static initializer (debugobjects) */
- WORK_STRUCT_COLOR_SHIFT = 3, /* color for workqueue flushing */
+ WORK_STRUCT_STATIC_BIT = 3, /* static initializer (debugobjects) */
+ WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
#else
- WORK_STRUCT_COLOR_SHIFT = 2, /* color for workqueue flushing */
+ WORK_STRUCT_COLOR_SHIFT = 3, /* color for workqueue flushing */
#endif
WORK_STRUCT_COLOR_BITS = 4,
WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
+ WORK_STRUCT_CWQ = 1 << WORK_STRUCT_CWQ_BIT,
WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
#ifdef CONFIG_DEBUG_OBJECTS_WORK
WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
WORK_NO_COLOR = WORK_NR_COLORS,
+ /* special cpu IDs */
+ WORK_CPU_UNBOUND = NR_CPUS,
+ WORK_CPU_NONE = NR_CPUS + 1,
+ WORK_CPU_LAST = WORK_CPU_NONE,
+
/*
- * Reserve 6 bits off of cwq pointer w/ debugobjects turned
- * off. This makes cwqs aligned to 64 bytes which isn't too
+ * Reserve 7 bits off of cwq pointer w/ debugobjects turned
+ * off. This makes cwqs aligned to 128 bytes which isn't too
* excessive while allowing 15 workqueue flush colors.
*/
WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
+ WORK_STRUCT_NO_CPU = WORK_CPU_NONE << WORK_STRUCT_FLAG_BITS,
+
+ /* bit mask for work_busy() return values */
+ WORK_BUSY_PENDING = 1 << 0,
+ WORK_BUSY_RUNNING = 1 << 1,
};
struct work_struct {
#endif
};
-#define WORK_DATA_INIT() ATOMIC_LONG_INIT(0)
-#define WORK_DATA_STATIC_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_STATIC)
+#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU)
+#define WORK_DATA_STATIC_INIT() \
+ ATOMIC_LONG_INIT(WORK_STRUCT_NO_CPU | WORK_STRUCT_STATIC)
struct delayed_work {
struct work_struct work;
clear_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
enum {
- WQ_FREEZEABLE = 1 << 0, /* freeze during suspend */
- WQ_SINGLE_THREAD = 1 << 1, /* no per-cpu worker */
+ WQ_NON_REENTRANT = 1 << 0, /* guarantee non-reentrance */
+ WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
+ WQ_FREEZEABLE = 1 << 2, /* freeze during suspend */
+ WQ_RESCUER = 1 << 3, /* has an rescue worker */
+ WQ_HIGHPRI = 1 << 4, /* high priority */
+ WQ_CPU_INTENSIVE = 1 << 5, /* cpu instensive workqueue */
+
+ WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
+ WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
+ WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
};
+/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
+#define WQ_UNBOUND_MAX_ACTIVE \
+ max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
+
+/*
+ * System-wide workqueues which are always present.
+ *
+ * system_wq is the one used by schedule[_delayed]_work[_on]().
+ * Multi-CPU multi-threaded. There are users which expect relatively
+ * short queue flush time. Don't queue works which can run for too
+ * long.
+ *
+ * system_long_wq is similar to system_wq but may host long running
+ * works. Queue flushing might take relatively long.
+ *
+ * system_nrt_wq is non-reentrant and guarantees that any given work
+ * item is never executed in parallel by multiple CPUs. Queue
+ * flushing might take relatively long.
+ *
+ * system_unbound_wq is unbound workqueue. Workers are not bound to
+ * any specific CPU, not concurrency managed, and all queued works are
+ * executed immediately as long as max_active limit is not reached and
+ * resources are available.
+ */
+extern struct workqueue_struct *system_wq;
+extern struct workqueue_struct *system_long_wq;
+extern struct workqueue_struct *system_nrt_wq;
+extern struct workqueue_struct *system_unbound_wq;
+
extern struct workqueue_struct *
-__create_workqueue_key(const char *name, unsigned int flags, int max_active,
- struct lock_class_key *key, const char *lock_name);
+__alloc_workqueue_key(const char *name, unsigned int flags, int max_active,
+ struct lock_class_key *key, const char *lock_name);
#ifdef CONFIG_LOCKDEP
-#define __create_workqueue(name, flags, max_active) \
+#define alloc_workqueue(name, flags, max_active) \
({ \
static struct lock_class_key __key; \
const char *__lock_name; \
else \
__lock_name = #name; \
\
- __create_workqueue_key((name), (flags), (max_active), \
- &__key, __lock_name); \
+ __alloc_workqueue_key((name), (flags), (max_active), \
+ &__key, __lock_name); \
})
#else
-#define __create_workqueue(name, flags, max_active) \
- __create_workqueue_key((name), (flags), (max_active), NULL, NULL)
+#define alloc_workqueue(name, flags, max_active) \
+ __alloc_workqueue_key((name), (flags), (max_active), NULL, NULL)
#endif
#define create_workqueue(name) \
- __create_workqueue((name), 0, 1)
+ alloc_workqueue((name), WQ_RESCUER, 1)
#define create_freezeable_workqueue(name) \
- __create_workqueue((name), WQ_FREEZEABLE | WQ_SINGLE_THREAD, 1)
+ alloc_workqueue((name), WQ_FREEZEABLE | WQ_UNBOUND | WQ_RESCUER, 1)
#define create_singlethread_workqueue(name) \
- __create_workqueue((name), WQ_SINGLE_THREAD, 1)
+ alloc_workqueue((name), WQ_UNBOUND | WQ_RESCUER, 1)
extern void destroy_workqueue(struct workqueue_struct *wq);
extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
unsigned long delay);
extern int schedule_on_each_cpu(work_func_t func);
-extern int current_is_keventd(void);
extern int keventd_up(void);
-extern void init_workqueues(void);
int execute_in_process_context(work_func_t fn, struct execute_work *);
extern int flush_work(struct work_struct *work);
-
extern int cancel_work_sync(struct work_struct *work);
+extern void workqueue_set_max_active(struct workqueue_struct *wq,
+ int max_active);
+extern bool workqueue_congested(unsigned int cpu, struct workqueue_struct *wq);
+extern unsigned int work_cpu(struct work_struct *work);
+extern unsigned int work_busy(struct work_struct *work);
+
/*
* Kill off a pending schedule_delayed_work(). Note that the work callback
* function may still be running on return from cancel_delayed_work(), unless
extern void thaw_workqueues(void);
#endif /* CONFIG_FREEZER */
+#ifdef CONFIG_LOCKDEP
+int in_workqueue_context(struct workqueue_struct *wq);
+#endif
+
#endif
projects / linux-block.git / blobdiff