From mboxrd@z Thu Jan 1 00:00:00 1970 From: catalin.marinas@arm.com (Catalin Marinas) Date: Wed, 13 Sep 2017 15:11:23 -0700 Subject: [PATCH v2 14/28] arm64/sve: Backend logic for setting the vector length In-Reply-To: <20170913190611.GC23415@e103592.cambridge.arm.com> References: <1504198860-12951-1-git-send-email-Dave.Martin@arm.com> <1504198860-12951-15-git-send-email-Dave.Martin@arm.com> <20170913172911.3ca2h6cpju7etifi@localhost> <20170913190611.GC23415@e103592.cambridge.arm.com> Message-ID: <20170913221123.y4znytmxtplx24m4@localhost> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Sep 13, 2017 at 08:06:12PM +0100, Dave P Martin wrote: > On Wed, Sep 13, 2017 at 10:29:11AM -0700, Catalin Marinas wrote: > > On Thu, Aug 31, 2017 at 06:00:46PM +0100, Dave P Martin wrote: > > > This patch implements the core logic for changing a task's vector > > > length on request from userspace. This will be used by the ptrace > > > and prctl frontends that are implemented in later patches. > > > > > > The SVE architecture permits, but does not require, implementations > > > to support vector lengths that are not a power of two. To handle > > > this, logic is added to check a requested vector length against a > > > possibly sparse bitmap of available vector lengths at runtime, so > > > that the best supported value can be chosen. > > > > > > Signed-off-by: Dave Martin > > > Cc: Alex Benn?e > > > > Can this be merged with patch 20? It seems to add the PR_ definitions > > which get actually used later when the prctl interface is added. > > This patch is used both by patch 19 and by patch 20, which I preferred > not to merge with each other: ptrace and prctl are significantly > different things. > > The prctl bit definitions are added here because they are the canonical > definitions used by both interfaces. The ptrace #defines are based on > them. > > Does it make sense if I merge patch 20 into this one and apply patch 19 > on top? This avoide the appearance of prctl #defines with no prctl > implementation. That's fine, you can bring patch 20 forward. If there are other non-trivial issues, feel free to ignore my comment. -- Catalin