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From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: David Miller <davem@davemloft.net>,
	Sebastian Sewior <bigeasy@linutronix.de>,
	Daniel Borkmann <daniel@iogearbox.net>, bpf <bpf@vger.kernel.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Martin KaFai Lau <kafai@fb.com>, Song Liu <songliubraving@fb.com>,
	Yonghong Song <yhs@fb.com>, Peter Zijlstra <peterz@infradead.org>,
	Clark Williams <williams@redhat.com>
Subject: Re: [PATCH] BPF: Disable on PREEMPT_RT
Date: Thu, 17 Oct 2019 16:27:11 -0700	[thread overview]
Message-ID: <CAADnVQJPJubTx0TxcXnbCfavcQDZeu8VTnYYpa8JYpWw9Ze4qg@mail.gmail.com> (raw)
In-Reply-To: <alpine.DEB.2.21.1910172342090.1869@nanos.tec.linutronix.de>

On Thu, Oct 17, 2019 at 2:54 PM Thomas Gleixner <tglx@linutronix.de> wrote:
>
> I'm all ears for an alternative solution. Here are the pain points:

Let's talk about them one by one.

>   #1) BPF disables preemption unconditionally with no way to do a proper RT
>       substitution like most other infrastructure in the kernel provides
>       via spinlocks or other locking primitives.

Kernel has a ton of code that disables preemption.
Why BPF is somehow special?
Are you saying RT kernel doesn't disable preemption at all?
I'm complete noob in RT.

  parent reply	other threads:[~2019-10-17 23:27 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-17  9:05 [PATCH] BPF: Disable on PREEMPT_RT Sebastian Andrzej Siewior
2019-10-17 14:53 ` Daniel Borkmann
2019-10-17 15:40   ` Sebastian Andrzej Siewior
2019-10-17 17:25     ` David Miller
2019-10-17 21:54       ` Thomas Gleixner
2019-10-17 22:13         ` David Miller
2019-10-17 23:50           ` Thomas Gleixner
2019-10-17 23:27         ` Alexei Starovoitov [this message]
2019-10-18  0:22           ` Thomas Gleixner
2019-10-18  5:52             ` Alexei Starovoitov
2019-10-18 11:28               ` Thomas Gleixner
2019-10-18 12:48                 ` Sebastian Sewior
2019-10-18 23:05                 ` Alexei Starovoitov
2019-10-20  9:06                   ` Thomas Gleixner
2019-10-22  1:43                     ` Alexei Starovoitov
2019-10-18  2:49         ` Clark Williams
2019-10-18  4:57           ` David Miller
2019-10-18  5:54             ` Alexei Starovoitov
2019-10-18  8:38             ` Thomas Gleixner
2019-10-18 12:49               ` Clark Williams
2019-10-18  8:46           ` Thomas Gleixner
2019-10-18 12:43             ` Sebastian Sewior
2019-10-18 12:58             ` Clark Williams
2019-10-17 22:11       ` Thomas Gleixner
2019-10-17 22:23         ` David Miller
2019-10-17 17:26   ` David Miller

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