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x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 8E03DC0008 X-Stat-Signature: g75gq8zhqdf5cg8i7f49oo65ypp7eyma X-HE-Tag: 1679677626-818196 X-HE-Meta: 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 GbNoU+9e n1isnBoTD1war+1QU9wdNtId46O2zeoMquDYkMImF8c4hkdkcSFlJvuSGrs86QCRyA4/Qo172SAp9yXvFzJfIYoLoHP8oNiYBDHIrXcWYq/D7GeQI/xN5+4rW7vpycGFABJD99udOozB2WnAKzB7jhPSC9pk5E9teGJovhPQMqXAQyjc+mgAtBI/CSffFNuYurCrT9zL0hlsXEO+/ZuptGf3TSANw9x9/lIyMXzQSimlr1OSsj5Ym9ce6hpl7gZ8QccgCpmz1r6zNOeZDIowqkdQtWwjYYu/xiVGBZoj31BfHg+5Kp+DY7+7TKA== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 24 Mar 2023 09:43:53 -0700 Beau Belgrave wrote: > > It was actually merged in 5.8. So sysctl should be sufficient with that. > > But maybe it's weird to start adding sysctls, when the rest of tracing > > tunables is AFAIK under /sys/kernel/tracing/ ? > > > > During the TraceFS meetings Steven runs I was asked to add a boot > parameter and sysctl for user_events to limit the max. > > To me, it seems when user_events moves toward namespace awareness > sysctl might be easier to use from within a namespace to turn knobs. > > Happy to change to whatever, but I want to see Steven and Masami agree > on the approach before doing so. > > Steven, do you agree with Masami to move to just sysctl? We do have some tracing related sysctls already: # cd /proc/sys/kernel # ls *trace* ftrace_dump_on_oops oops_all_cpu_backtrace traceoff_on_warning ftrace_enabled stack_tracer_enabled tracepoint_printk Although I would love to deprecated ftrace_enable as that now has a control in tracefs, but it's not unprecedented to have tracing tunables as sysctl. And if we get cmdline boot parameters for free from sysctls then all the better. -- Steve