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Date:   Wed, 21 Nov 2018 23:41:24 +0100
From:   Andrea Parri <andrea.parri@amarulasolutions.com>
To:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@redhat.com>,
        Namhyung Kim <namhyung@kernel.org>,
        Oleg Nesterov <oleg@redhat.com>
Cc:     linux-kernel@vger.kernel.org
Subject: [Question] smp_wmb() in prepare_uprobe()
Message-ID: <20181121224124.GB4016@andrea>
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Hi,

The comment for the smp_wmb() in prepare_uprobe() says:

  "pairs with rmb() in find_active_uprobe()"

but I see no (smp_)rmb() in find_active_uprobe(); I see the smp_rmb() in
handle_swbp(): is this the intended pairing barrier?

Which memory accesses do you want to "order" with this pairing?

Thanks,
  Andrea