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Date: Fri, 8 Sep 2023 13:56:02 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Mattias =?UTF-8?B?UsO2bm5ibG9t?= <hofors@lysator.liu.se>
Cc: dev@dpdk.org, Mattias =?UTF-8?B?UsO2bm5ibG9t?=
<mattias.ronnblom@ericsson.com>, Bruce Richardson
<bruce.richardson@intel.com>
Subject: Re: [PATCH v2 2/2] random: make rte_rand() thread safe for non-EAL
threads
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On Fri, 8 Sep 2023 22:48:54 +0200
Mattias R=C3=B6nnblom <hofors@lysator.liu.se> wrote:
> On 2023-09-07 17:24, Stephen Hemminger wrote:
> > Add missing locking so that if two non-EAL threads call rte_rand()
> > they will not corrupt the per-thread state.
> >=20
> > Fixes: 3f002f069612 ("eal: replace libc-based random generation with LF=
SR") =20
>=20
> The API documentation clearly states that no MT safety guarantees are=20
> given for unregistered non-EAL threads. So this patch doesn't fix anythin=
g.
>=20
> rte_rand() is MT safe for *registered* non-EAL threads.
Reading the documentation, it only guarantees safety if registered.
We should add an otherwise clause rather than leaving case as undefined.