Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20210123011704.1901835-1-joel@joelfernandes.org>
 <20210123011704.1901835-3-joel@joelfernandes.org> <YBwGRpnISmwkJ2i8@hirez.programming.kicks-ass.net>
In-Reply-To: <YBwGRpnISmwkJ2i8@hirez.programming.kicks-ass.net>
From:   Josh Don <joshdon@google.com>
Date:   Thu, 4 Feb 2021 20:07:18 -0800
Message-ID: <CABk29NukDGbO3V4MW8MMSkevjsbUfii0Scc9mpXsi+yRQmWxMA@mail.gmail.com>
Subject: Re: [PATCH v10 2/5] sched: CGroup tagging interface for core scheduling
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     "Joel Fernandes (Google)" <joel@joelfernandes.org>,
        Nishanth Aravamudan <naravamudan@digitalocean.com>,
        Julien Desfossez <jdesfossez@digitalocean.com>,
        Tim Chen <tim.c.chen@linux.intel.com>,
        Vineeth Pillai <viremana@linux.microsoft.com>,
        Aaron Lu <aaron.lwe@gmail.com>,
        Aubrey Li <aubrey.intel@gmail.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel <linux-kernel@vger.kernel.org>, mingo@kernel.org,
        torvalds@linux-foundation.org, fweisbec@gmail.com,
        Kees Cook <keescook@chromium.org>,
        Greg Kerr <kerrnel@google.com>, Phil Auld <pauld@redhat.com>,
        Valentin Schneider <valentin.schneider@arm.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Pawan Gupta <pawan.kumar.gupta@linux.intel.com>,
        Paolo Bonzini <pbonzini@redhat.com>, vineeth@bitbyteword.org,
        Chen Yu <yu.c.chen@intel.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        Agata Gruza <agata.gruza@intel.com>,
        Antonio Gomez Iglesias <antonio.gomez.iglesias@intel.com>,
        graf@amazon.com, konrad.wilk@oracle.com, dfaggioli@suse.com,
        Paul Turner <pjt@google.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Patrick Bellasi <derkling@google.com>, benbjiang@tencent.com,
        Alexandre Chartre <alexandre.chartre@oracle.com>,
        James.Bottomley@hansenpartnership.com, OWeisse@umich.edu,
        Dhaval Giani <dhaval.giani@oracle.com>,
        Junaid Shahid <junaids@google.com>,
        Jesse Barnes <jsbarnes@google.com>,
        "Hyser,Chris" <chris.hyser@oracle.com>,
        Ben Segall <bsegall@google.com>, Hao Luo <haoluo@google.com>,
        Tom Lendacky <thomas.lendacky@amd.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Thu, Feb 4, 2021 at 6:36 AM Peter Zijlstra <peterz@infradead.org> wrote:
>
> refcount_dec_and_lock() avoids that complication.

There isn't currently an interface for raw_spin_locks. Certainly could
add a new interface in a separate patch as part of this series, but
doesn't seem that bad to do the locking inline.