From mboxrd@z Thu Jan  1 00:00:00 1970
From: Oleg Nesterov <oleg@redhat.com>
Subject: Re: [PATCH 1/2] bcache: ignore pending signals in
 bcache_device_init()
Date: Wed, 4 Mar 2020 13:13:25 +0100
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To: Michal Hocko <mhocko@kernel.org>
Cc: Coly Li <colyli@suse.de>, axboe@kernel.dk, linux-bcache@vger.kernel.org, linux-block@vger.kernel.org, hare@suse.de, mkoutny@suse.com
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On 03/04, Michal Hocko wrote:
>
> So what would be a legit usecase to drop all signals while explicitly
> calling allow_signal?

Not sure I understand... Did you mean kthread should use kernel_dequeue
rather than flush?

Yes, they should do the same if kthread allows a single signal, iow if
it calls allow_signal() once.

But currently they differ.

1. flush_signal() is faster but we can optimize kernel_dequeue_signal().

2. kernel_dequeue_signal() does not necessarily clears TIF_SIGPENDING
   and I think this needs some fixes. Probably klp_patch_pending() is
   the only problem...

Oleg.