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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000093, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, Nov 12, 2020 at 5:09 PM Marco Elver wrote: > > On Thu, 12 Nov 2020 at 16:59, Alexander Potapenko wro= te: > > > > On Tue, Nov 10, 2020 at 11:12 PM Andrey Konovalov wrote: > > > > > > From: Vincenzo Frascino > > > > > > This test is specific to MTE and verifies that the GCR_EL1 register > > > is context switched correctly. > > > > > > It spawn 1024 processes and each process spawns 5 threads. Each threa= d > > > > Nit: "spawns" > > > > > > > + srand(time(NULL) ^ (pid << 16) ^ (tid << 16)); > > > + > > > + prctl_tag_mask =3D rand() % 0xffff; > > > > Nit: if you want values between 0 and 0xffff you probably want to use > > bitwise AND. > > Another question would be, is the max here meant to be 0xffff or > 0xffff-1. Because, as-is now, it's 0xffff-1. Only one of them has a > trivial conversion to bitwise AND ( x % 2^n =3D=3D x & (2^n - 1) ). Yes, that is basically what I meant, assuming that Vincenzo wanted the max to be 0xffff --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg