[Devel] [PATCH VZ10 v3 1/2] ve/sunrpc: Refactor {rpc, write}_kill_tasks

[Pavel Tikhomirov]

On 6/5/26 20:33, Vladimir Riabchun wrote:
> 1. Rename rpc_kill_tasks to rpc_set_kill_net and add value parameter,
>    so that function can now both enable and disable RPC traffic.
> 2. Move sn->kill_tasks check to rpc_set_kill_net so that
>    file write function is only responsible for parsing and calling,
>    not for logic checks.
> 
> This will allow later usage of rpc_set_kill_net without
> kill_tasks check duplication.
> 
> https://virtuozzo.atlassian.net/browse/VSTOR-126316
> 
> Feature: improve kill-tasks
> Signed-off-by: Vladimir Riabchun <vladimir.riabchun at virtuozzo.com>
> ---
> v2 -> v3:
>  - Rename rpc_kill_tasks and add a new parameter
>  - Support clearing sn->kill_tasks in rpc_set_kill_net
> 
>  net/sunrpc/clnt.c | 35 ++++++++++++++++++++---------------
>  1 file changed, 20 insertions(+), 15 deletions(-)
> 
> diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
> index 266cf0fbbad5..0b7f69eb910d 100644
> --- a/net/sunrpc/clnt.c
> +++ b/net/sunrpc/clnt.c
> @@ -3406,15 +3406,32 @@ rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
>  EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
>  #endif /* CONFIG_SUNRPC_SWAP */
>  
> -static void rpc_kill_tasks(struct net *net)
> +static void rpc_set_kill_net(struct net *net, bool new_value)
>  {
>  	struct rpc_clnt *clnt;
>  	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
> +	if (sn->kill_tasks == new_value)
> +		return;
> +
> +	sn->kill_tasks = new_value;
> +	if (!new_value) {
> +		pr_info_ratelimited(
> +			"task (%s:%d) cleared RPC kill_tasks in net [%u]\n",
> +			current->comm, current->pid, net->ns.inum);
> +		return;
> +	}
>  
>  	spin_lock(&sn->rpc_client_lock);
>  	list_for_each_entry(clnt, &sn->all_clients, cl_clients)
>  		rpc_killall_tasks(clnt);
>  	spin_unlock(&sn->rpc_client_lock);
> +
> +	pr_info_ratelimited("task (%s:%d) killed RPC in net:[%u]%s\n",
> +			    current->comm, current->pid, net->ns.inum,
> +#ifdef CONFIG_VE
> +			    net->owner_ve == &ve0 ? "(host)" :
> +#endif
> +			    "");
>  }
>  
>  static ssize_t write_kill_tasks(struct file *file, const char __user *buf,
> @@ -3422,7 +3439,6 @@ static ssize_t write_kill_tasks(struct file *file, const char __user *buf,
>  {
>  	struct net *net = pde_data(file->f_path.dentry->d_inode);
>  	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
> -	bool prev_kill_tasks = sn->kill_tasks;
>  	char tbuf[20];
>  	unsigned long kill_tasks;
>  	int res;
> @@ -3437,19 +3453,8 @@ static ssize_t write_kill_tasks(struct file *file, const char __user *buf,
>  	if (res)
>  		return res;
>  
> -	sn->kill_tasks = !!kill_tasks;
> -
> -	/* Kill pending tasks */
> -	if (sn->kill_tasks && !prev_kill_tasks) {
> -		rpc_kill_tasks(net);
> -		pr_info_ratelimited(
> -			"kill-tasks: by task (%s:%d) in net:[%u]%s\n",
> -			current->comm, current->pid, net->ns.inum,
> -#ifdef CONFIG_VE
> -			net->owner_ve == &ve0 ? "(host)" :
> -#endif
> -			"");
> -	}
> +	/* Kill pending tasks or forget about previous murder */
> +	rpc_set_kill_net(net, kill_tasks);

jfyi: unused sn

net/sunrpc/clnt.c: In function ‘write_kill_tasks’:
net/sunrpc/clnt.c:3469:28: warning: unused variable ‘sn’ [-Wunused-variable]
 3469 |         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
      |                            ^~

>  
>  	return count;
>  }

-- 
Best regards, Pavel Tikhomirov
Senior Software Developer, Virtuozzo.