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Mon, 03 Feb 2025 15:03:06 -0500 X-MC-Unique: tsUddE3HMUqiq6MKQfSz1w-1 X-Mimecast-MFC-AGG-ID: tsUddE3HMUqiq6MKQfSz1w Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 603E0180035F; Mon, 3 Feb 2025 20:03:04 +0000 (UTC) Received: from dhcp-27-174.brq.redhat.com (unknown [10.45.224.72]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with SMTP id 61AD318008C0; Mon, 3 Feb 2025 20:03:01 +0000 (UTC) Received: by dhcp-27-174.brq.redhat.com (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Mon, 3 Feb 2025 21:02:38 +0100 (CET) Date: Mon, 3 Feb 2025 21:02:34 +0100 From: Oleg Nesterov To: Mateusz Guzik Cc: ebiederm@xmission.com, brauner@kernel.org, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 5/6] pid: perform free_pid() calls outside of tasklist_lock Message-ID: <20250203200233.GE1003@redhat.com> References: <20250201163106.28912-1-mjguzik@gmail.com> <20250201163106.28912-6-mjguzik@gmail.com> <20250203184908.GD1003@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 X-Rspamd-Queue-Id: 7D2791C0010 X-Stat-Signature: 71eh8e95rznrtraeq1iacfb4hoaak8ug X-Rspam-User: X-Rspamd-Server: rspam12 X-HE-Tag: 1738612988-749098 X-HE-Meta: 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 1jrB/yZM PNfe7qbD2NPGzHA4FzqN2NKjMTvRIxIXjw9BnZlMCiBARPGML3d1+UYtMjjOHoxzBvpqfhN3yzCf0etXsyiOvvIFhZz7BtozWga3C4AHZK4s7o+sQ76/iFnTeXLHwEyGBD99r+CQnxwh5e56pDp61XwaKRCPcXDxOf4DQicSvSW7euPbbi3RBCG3AHISqrJCbmZGvjS5Of5A5sbyZdZYPr/screFtv/KW8EqTm/kjCGZhxYl0pvYUnYIuzwpKM9fnuqabZVC0QGIjvztM66thqFzd6Fn6Vh0CsEYmFuk+hdrWGul71+MXb0a3GkYH6srWw+911oAOgs0HZTRixumPOMgH4B9KzYOAFCJLDGK5+Qzw5uOM+w8fb+g7dbwd4xbPWMEJLS/OqmDrNhwrFgeCbdyaNw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.032603, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 02/03, Mateusz Guzik wrote: > > On Mon, Feb 3, 2025 at 7:49 PM Oleg Nesterov wrote: > > > > To avoid the confusion, my question and a note are absolutely offtopic. > > > > On 02/01, Mateusz Guzik wrote: > > > > > > @@ -1085,6 +1085,7 @@ SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) > > > { > > > struct task_struct *p; > > > struct task_struct *group_leader = current->group_leader; > > > + struct pid *pids[PIDTYPE_MAX] = { 0 }; > > > > Could you remind me why > > > > struct pid *pids[PIDTYPE_MAX] = {}; > > > > is not right? I seem to knew it some time before, but can't recall... > > > > as far as I know this is merely a matter of convention, fwiw a naive grep: > $ git grep '= { }' | wc -l > 1273 > $ git grep '= { 0 }' | wc -l > 2031 > $ git grep '= {}' | wc -l > 5626 OK... but I still have a vague feeling that it was explained somewhere that '{ 0 }' should be preferred... Nevermind. > that said i can change it to whatever you see fit No, please do whatever looks better to you. Oleg.