Currently, when a work item is off queue, high bits of its data encodes the last CPU it was on. This is scheduled to be changed to pool ID, which will make it impossible to use WORK_CPU_NONE to indicate no association. This patch limits the number of bits which are used for off-queue cpu number to 31 (so that the max fits in an int) and uses the highest possible value - WORK_OFFQ_CPU_NONE - to indicate no association.
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| @@ -573,7 +573,7 @@ static struct global_cwq *get_work_gcwq(struct work_struct *work) · 572 unmodified lines | |||
| 573 | (data & WORK_STRUCT_WQ_DATA_MASK))->pool->gcwq; | 573 | (data & WORK_STRUCT_WQ_DATA_MASK))->pool->gcwq; |
| 574 | 574 | ||
| 575 | cpu = data >> WORK_OFFQ_CPU_SHIFT; | 575 | cpu = data >> WORK_OFFQ_CPU_SHIFT; |
| 576 | if (cpu == WORK_CPU_NONE) | 576 | if (cpu == WORK_OFFQ_CPU_NONE) |
| 577 | return NULL; | 577 | return NULL; |
| 578 | 578 | ||
| 579 | BUG_ON(cpu >= nr_cpu_ids && cpu != WORK_CPU_UNBOUND); | 579 | BUG_ON(cpu >= nr_cpu_ids && cpu != WORK_CPU_UNBOUND); |
| @@ -583,7 +583,7 @@ static struct global_cwq *get_work_gcwq(struct work_struct *work) · 3 unmodified lines | |||
| 583 | static void mark_work_canceling(struct work_struct *work) | 583 | static void mark_work_canceling(struct work_struct *work) |
| 584 | { | 584 | { |
| 585 | struct global_cwq *gcwq = get_work_gcwq(work); | 585 | struct global_cwq *gcwq = get_work_gcwq(work); |
| 586 | unsigned long cpu = gcwq ? gcwq->cpu : WORK_CPU_NONE; | 586 | unsigned long cpu = gcwq ? gcwq->cpu : WORK_OFFQ_CPU_NONE; |
| 587 | 587 | ||
| 588 | set_work_data(work, (cpu << WORK_OFFQ_CPU_SHIFT) | WORK_OFFQ_CANCELING, | 588 | set_work_data(work, (cpu << WORK_OFFQ_CPU_SHIFT) | WORK_OFFQ_CANCELING, |
| 589 | WORK_STRUCT_PENDING); | 589 | WORK_STRUCT_PENDING); |