Re: [PATCH] aio: block exit_aio() until all context requests are completed

[Benjamin LaHaise <bcrl@kvack.org>]

Hi Gu,

On Wed, Sep 03, 2014 at 05:45:44PM +0800, Gu Zheng wrote:
> It seems that exit_aio() also needs to wait for all iocbs to complete (like
> io_destroy), but we missed the wait step in current implemention, so fix
> it in the same way as we did in io_destroy.

I actually already have another version of this patch queued up that 
checks the return value of kill_ioctx().

		-ben

> Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
> ---
>  fs/aio.c |    7 ++++++-
>  1 files changed, 6 insertions(+), 1 deletions(-)
> 
> diff --git a/fs/aio.c b/fs/aio.c
> index 97bc62c..3e35b12 100644
> --- a/fs/aio.c
> +++ b/fs/aio.c
> @@ -793,6 +793,8 @@ void exit_aio(struct mm_struct *mm)
>  
>  	for (i = 0; i < table->nr; ++i) {
>  		struct kioctx *ctx = table->table[i];
> +		struct completion requests_done =
> +			COMPLETION_INITIALIZER_ONSTACK(requests_done);
>  
>  		if (!ctx)
>  			continue;
> @@ -804,7 +806,10 @@ void exit_aio(struct mm_struct *mm)
>  		 * that it needs to unmap the area, just set it to 0.
>  		 */
>  		ctx->mmap_size = 0;
> -		kill_ioctx(mm, ctx, NULL);
> +		kill_ioctx(mm, ctx, &requests_done);
> +
> +		/* Wait until all IO for the context are done. */
> +		wait_for_completion(&requests_done);
>  	}
>  
>  	RCU_INIT_POINTER(mm->ioctx_table, NULL);
> -- 
> 1.7.7

-- 
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