diff options
| -rw-r--r-- | include/linux/workqueue.h | 8 | ||||
| -rw-r--r-- | kernel/workqueue.c | 14 |
2 files changed, 16 insertions, 6 deletions
diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index ab95fef38d56..f562674db404 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -68,9 +68,15 @@ enum { WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT + WORK_STRUCT_COLOR_BITS, + /* data contains off-queue information when !WORK_STRUCT_CWQ */ + WORK_OFFQ_FLAG_BASE = WORK_STRUCT_FLAG_BITS, + WORK_OFFQ_FLAG_BITS = 0, + WORK_OFFQ_CPU_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS, + + /* convenience constants */ 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, + WORK_STRUCT_NO_CPU = (unsigned long)WORK_CPU_NONE << WORK_OFFQ_CPU_SHIFT, /* bit mask for work_busy() return values */ WORK_BUSY_PENDING = 1 << 0, diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 0f50f4078e36..eeae77079483 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -533,9 +533,9 @@ static int work_next_color(int color) } /* - * A work's data points to the cwq with WORK_STRUCT_CWQ set while the - * work is on queue. Once execution starts, WORK_STRUCT_CWQ is - * cleared and the work data contains the cpu number it was last on. + * While queued, %WORK_STRUCT_CWQ is set and non flag bits of a work's data + * contain the pointer to the queued cwq. Once execution starts, the flag + * is cleared and the high bits contain OFFQ flags and CPU number. * * set_work_cwq(), set_work_cpu_and_clear_pending() and clear_work_data() * can be used to set the cwq, cpu or clear work->data. These functions @@ -565,7 +565,7 @@ static void set_work_cwq(struct work_struct *work, static void set_work_cpu_and_clear_pending(struct work_struct *work, unsigned int cpu) { - set_work_data(work, cpu << WORK_STRUCT_FLAG_BITS, 0); + set_work_data(work, (unsigned long)cpu << WORK_OFFQ_CPU_SHIFT, 0); } static void clear_work_data(struct work_struct *work) @@ -592,7 +592,7 @@ static struct global_cwq *get_work_gcwq(struct work_struct *work) return ((struct cpu_workqueue_struct *) (data & WORK_STRUCT_WQ_DATA_MASK))->pool->gcwq; - cpu = data >> WORK_STRUCT_FLAG_BITS; + cpu = data >> WORK_OFFQ_CPU_SHIFT; if (cpu == WORK_CPU_NONE) return NULL; @@ -3724,6 +3724,10 @@ static int __init init_workqueues(void) unsigned int cpu; int i; + /* make sure we have enough bits for OFFQ CPU number */ + BUILD_BUG_ON((1LU << (BITS_PER_LONG - WORK_OFFQ_CPU_SHIFT)) < + WORK_CPU_LAST); + cpu_notifier(workqueue_cpu_up_callback, CPU_PRI_WORKQUEUE_UP); cpu_notifier(workqueue_cpu_down_callback, CPU_PRI_WORKQUEUE_DOWN); |