Re: [PATCH] bpf: convert hashtab lock to raw lock

From: Shi, Yang
Date: Mon Nov 02 2015 - 12:31:58 EST


On 11/2/2015 9:24 AM, Steven Rostedt wrote:
On Mon, 02 Nov 2015 09:12:29 -0800
"Shi, Yang" <yang.shi@xxxxxxxxxx> wrote:

Yes, it is common practice for converting sleepable spin lock to raw
spin lock in -rt to avoid scheduling in atomic context bug.

Note, in a lot of cases we don't just convert spin_locks to raw because
of atomic context. There's times we need to change the design where the
lock is not taken in atomic context (switching preempt_disable() to a
local_lock() for example).

Yes, definitely. Understood.

Thanks,
Yang


But bpf is much like ftrace and kprobes where they can be taken almost
anywhere, and the do indeed need to be raw.

-- Steve


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