Avoid that complaints like the one below are reported against a debug kernel:
NMI watchdog: BUG: soft lockup - CPU#1 stuck for 22s! [disk11_0:2708] irq event stamp: 17120809 hardirqs last enabled at (17120808): [<ffffffff81599191>] _raw_spin_unlock_irqrestore+0x31/0x50 hardirqs last disabled at (17120809): [<ffff88046f223bd0>] 0xffff88046f223bd0 softirqs last enabled at (17120794): [<ffffffffa060aa67>] scst_check_blocked_dev+0x77/0x1c0 [scst] softirqs last disabled at (17120795): [<ffffffff8159acbc>] do_softirq_own_stack+0x1c/0x30 RIP: 0010:[<ffffffff81599193>] [<ffffffff81599193>] _raw_spin_unlock_irqrestore+0x33/0x50 Call Trace: <IRQ> [<ffffffff81171450>] free_debug_processing+0x270/0x3a0 [<ffffffff8117277a>] __slab_free+0x17a/0x2c0 [<ffffffff81172a74>] kmem_cache_free+0x1b4/0x1d0 [<ffffffff8111a6c2>] mempool_free_slab+0x12/0x20 [<ffffffff8111a846>] mempool_free+0x26/0x80 [<ffffffff81294cb9>] bio_free+0x49/0x60 [<ffffffff81294cee>] bio_put+0x1e/0x30 [<ffffffffa0199d31>] end_clone_bio+0x21/0x70 [dm_mod] [<ffffffff81294d52>] bio_endio+0x52/0x60 [<ffffffff8129aaec>] blk_update_request+0x7c/0x2a0 [<ffffffff813f4a8e>] scsi_end_request+0x2e/0x1d0 [<ffffffff813f7674>] scsi_io_completion+0xb4/0x610 [<ffffffff813ee79a>] scsi_finish_command+0xca/0x120 [<ffffffff813f6ef0>] scsi_softirq_done+0x120/0x140 [<ffffffff812a26e6>] blk_done_softirq+0x76/0x90 [<ffffffff8105bc1f>] __do_softirq+0x10f/0x230 [<ffffffff8159acbc>] do_softirq_own_stack+0x1c/0x30 <EOI> Signed-off-by: Bart Van Assche <[email protected]> --- block/blk-softirq.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/block/blk-softirq.c b/block/blk-softirq.c index 53b1737..d4d2fe4 100644 --- a/block/blk-softirq.c +++ b/block/blk-softirq.c @@ -21,10 +21,22 @@ static DEFINE_PER_CPU(struct list_head, blk_cpu_done); static void blk_done_softirq(struct softirq_action *h) { struct list_head *cpu_list, local_list; + struct request *e; + bool reraise = false; + int i = 0; local_irq_disable(); cpu_list = this_cpu_ptr(&blk_cpu_done); + list_for_each_entry(e, cpu_list, ipi_list) { + if (++i < 256) + continue; + list_cut_position(&local_list, cpu_list, &e->ipi_list); + reraise = true; + goto enable_irq; + } list_replace_init(cpu_list, &local_list); + +enable_irq: local_irq_enable(); while (!list_empty(&local_list)) { @@ -34,6 +46,14 @@ static void blk_done_softirq(struct softirq_action *h) list_del_init(&rq->ipi_list); rq->q->softirq_done_fn(rq); } + + if (!reraise) + return; + + local_irq_disable(); + if (!list_empty(cpu_list)) + raise_softirq_irqoff(BLOCK_SOFTIRQ); + local_irq_enable(); } #ifdef CONFIG_SMP -- 2.7.3 -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
