On 2015/9/24 6:31, David Miller wrote:
> From: Weidong Wang <wangweido...@huawei.com>
> Date: Tue, 22 Sep 2015 20:42:40 +0800
>
>> @@ -880,6 +882,7 @@ bnx2_alloc_mem(struct bnx2 *bp)
>> }
>> }
>>
>> + spin_lock(&bp->stats64_lock);
>> bp->stats_blk = status_blk + status_blk_size;
>>
>> bp->stats_blk_mapping = bp->status_blk_mapping + status_blk_size;
>> @@ -894,20 +897,23 @@ bnx2_alloc_mem(struct bnx2 *bp)
>> &bp->ctx_blk_mapping[i],
>> GFP_KERNEL);
>> if (bp->ctx_blk[i] == NULL)
>> - goto alloc_mem_err;
>> + goto free_stats64_lock;
>> }
>> }
>>
>> err = bnx2_alloc_rx_mem(bp);
>> if (err)
>> - goto alloc_mem_err;
>> + goto free_stats64_lock;
>
> You're holding a spinlock while doing GFP_KERNEL allocations.
>
hm, yep, I should move it after the allocations. Like this:
@@ -880,7 +882,9 @@ bnx2_alloc_mem(struct bnx2 *bp)
}
}
+ spin_lock(&bp->stats64_lock);
bp->stats_blk = status_blk + status_blk_size;
+ spin_unlock(&bp->stats64_lock);
the allocations won't use the stats_blk, so I shouldn't hold the
lock while doing allocations.
> Second of all, taking a spinlock in get_stats64() defeats the whole
> intention of making statistics acquisition as fast and as SMP scalable
> as possible.
>
It does affect the intention. Although, the problem exists then makes the
system panic within some case.
Do you have any idea about it?
Best Regards,
Weidong
> .
>
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