From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave.Martin@arm.com (Dave Martin) Date: Wed, 13 Sep 2017 20:06:12 +0100 Subject: [PATCH v2 14/28] arm64/sve: Backend logic for setting the vector length In-Reply-To: <20170913172911.3ca2h6cpju7etifi@localhost> References: <1504198860-12951-1-git-send-email-Dave.Martin@arm.com> <1504198860-12951-15-git-send-email-Dave.Martin@arm.com> <20170913172911.3ca2h6cpju7etifi@localhost> Message-ID: <20170913190611.GC23415@e103592.cambridge.arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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. Cheers ---Dave