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Date:   Mon, 4 May 2020 17:31:35 +0200
From:   Joerg Roedel <jroedel@suse.de>
To:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc:     rostedt <rostedt@goodmis.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>,
        Thomas Gleixner <tglx@linutronix.de>,
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        Borislav Petkov <bp@alien8.de>,
        Andrew Morton <akpm@linux-foundation.org>,
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        Andy Lutomirski <luto@amacapital.net>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Tzvetomir Stoyanov <tz.stoyanov@gmail.com>
Subject: Re: [PATCH] percpu: Sync vmalloc mappings in pcpu_alloc() and
 free_percpu()
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On Mon, May 04, 2020 at 11:28:46AM -0400, Mathieu Desnoyers wrote:
> ----- On May 4, 2020, at 11:12 AM, Joerg Roedel jroedel@suse.de wrote:
> Placing this here is inefficient. It syncs mappings for each percpu allocation.
> I would recommend moving it right after __vmalloc() is called to allocate the
> underlying memory chunk instead:
> 
> static void *pcpu_mem_zalloc(size_t size, gfp_t gfp)
> {

Tried this before, actually I put it into the caller of
pcpu_mem_zalloc(), but that didn't fix the problem for me. Stevens
test-case still hangs the machine.


Regards,

	Joerg