From: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
To: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: Ian Jackson <Ian.Jackson@eu.citrix.com>,
Wei Liu <wei.liu2@citrix.com>, Tim Deegan <tim@xen.org>,
Ian Campbell <ian.campbell@citrix.com>,
Xen-devel <xen-devel@lists.xen.org>
Subject: Re: [PATCH v2 24/30] tools/libxc: Modify bitmap operations to take void pointers
Date: Wed, 17 Feb 2016 15:06:11 -0500 [thread overview]
Message-ID: <20160217200611.GL24109@char.us.oracle.com> (raw)
In-Reply-To: <56BB0BD0.6020009@citrix.com>
On Wed, Feb 10, 2016 at 10:07:12AM +0000, Andrew Cooper wrote:
> On 08/02/16 16:36, Ian Campbell wrote:
> > On Mon, 2016-02-08 at 16:23 +0000, Tim Deegan wrote:
> >> At 13:42 +0000 on 05 Feb (1454679737), Andrew Cooper wrote:
> >>> The type of the pointer to a bitmap is not interesting; it does not
> >>> affect the
> >>> representation of the block of bits being pointed to.
> >> It does affect the alignment, though. Is this safe on ARM?
> > Good point. These constructs in the patch:
> >
> > + const unsigned long *addr = _addr;
> >
> > Would be broken if _addr were not suitably aligned for an unsigned long.
> >
> > That probably rules out this approach unfortunately.
>
> What about reworking libxc bitops in terms of unsigned char? That
> should cover all alignment issues.
See 3cab67ac83b1d56c3daedd9c4adfed497a114246
"+/*
+ * xc_bitops.h has macros that do this as well - however they assume that
+ * the bitmask is word aligned but xc_cpumap_t is only guaranteed to be
+ * byte aligned and so we need byte versions for architectures which do
+ * not support misaligned accesses (which is basically everyone
+ * but x86, although even on x86 it can be inefficient).
+ */
"
>
> ~Andrew
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2016-02-17 20:06 UTC|newest]
Thread overview: 139+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-05 13:41 [PATCH RFC v2 00/30] x86: Improvements to cpuid handling for guests Andrew Cooper
2016-02-05 13:41 ` [PATCH v2 01/30] xen/x86: Drop X86_FEATURE_3DNOW_ALT Andrew Cooper
2016-02-05 13:41 ` [PATCH v2 02/30] xen/x86: Do not store VIA/Cyrix/Centaur CPU features Andrew Cooper
2016-02-05 13:41 ` [PATCH v2 03/30] xen/x86: Drop cpuinfo_x86.x86_power Andrew Cooper
2016-02-05 13:41 ` [PATCH v2 04/30] xen/x86: Improvements to pv_cpuid() Andrew Cooper
2016-02-05 13:41 ` [PATCH v2 05/30] xen/public: Export cpu featureset information in the public API Andrew Cooper
2016-02-12 16:27 ` Jan Beulich
2016-02-17 13:08 ` Andrew Cooper
2016-02-17 13:34 ` Jan Beulich
2016-02-19 17:29 ` Joao Martins
2016-02-19 17:55 ` Andrew Cooper
2016-02-19 22:03 ` Joao Martins
2016-02-20 16:17 ` Andrew Cooper
2016-02-20 17:39 ` Joao Martins
2016-02-20 19:17 ` Andrew Cooper
2016-02-22 18:50 ` Joao Martins
2016-02-05 13:41 ` [PATCH v2 06/30] xen/x86: Script to automatically process featureset information Andrew Cooper
2016-02-12 16:36 ` Jan Beulich
2016-02-12 16:43 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 07/30] xen/x86: Collect more cpuid feature leaves Andrew Cooper
2016-02-12 16:38 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 08/30] xen/x86: Mask out unknown features from Xen's capabilities Andrew Cooper
2016-02-12 16:43 ` Jan Beulich
2016-02-12 16:48 ` Andrew Cooper
2016-02-12 17:14 ` Jan Beulich
2016-02-17 13:12 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 09/30] xen/x86: Store antifeatures inverted in a featureset Andrew Cooper
2016-02-12 16:47 ` Jan Beulich
2016-02-12 16:50 ` Andrew Cooper
2016-02-12 17:15 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 10/30] xen/x86: Annotate VM applicability in featureset Andrew Cooper
2016-02-12 17:05 ` Jan Beulich
2016-02-12 17:42 ` Andrew Cooper
2016-02-15 9:20 ` Jan Beulich
2016-02-15 14:38 ` Andrew Cooper
2016-02-15 14:50 ` Jan Beulich
2016-02-15 14:53 ` Andrew Cooper
2016-02-15 15:02 ` Jan Beulich
2016-02-15 15:41 ` Andrew Cooper
2016-02-17 19:02 ` Is: PVH dom0 - MWAIT detection logic to get deeper C-states exposed in ACPI AML code. Was:Re: " Konrad Rzeszutek Wilk
2016-02-17 19:58 ` Boris Ostrovsky
2016-02-18 15:02 ` Roger Pau Monné
2016-02-18 15:12 ` Andrew Cooper
2016-02-18 16:24 ` Boris Ostrovsky
2016-02-18 16:48 ` Andrew Cooper
2016-02-18 17:03 ` Roger Pau Monné
2016-02-18 22:08 ` Konrad Rzeszutek Wilk
2016-02-18 15:16 ` David Vrabel
2016-02-05 13:42 ` [PATCH v2 11/30] xen/x86: Calculate maximum host and guest featuresets Andrew Cooper
2016-02-15 13:37 ` Jan Beulich
2016-02-15 14:57 ` Andrew Cooper
2016-02-15 15:07 ` Jan Beulich
2016-02-15 15:52 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 12/30] xen/x86: Generate deep dependencies of features Andrew Cooper
2016-02-15 14:06 ` Jan Beulich
2016-02-15 15:28 ` Andrew Cooper
2016-02-15 15:52 ` Jan Beulich
2016-02-15 16:09 ` Andrew Cooper
2016-02-15 16:27 ` Jan Beulich
2016-02-15 19:07 ` Andrew Cooper
2016-02-16 9:54 ` Jan Beulich
2016-02-17 10:25 ` Andrew Cooper
2016-02-17 10:42 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 13/30] xen/x86: Clear dependent features when clearing a cpu cap Andrew Cooper
2016-02-15 14:53 ` Jan Beulich
2016-02-15 15:33 ` Andrew Cooper
2016-02-15 14:56 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 14/30] xen/x86: Improve disabling of features which have dependencies Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 15/30] xen/x86: Improvements to in-hypervisor cpuid sanity checks Andrew Cooper
2016-02-15 15:43 ` Jan Beulich
2016-02-15 17:12 ` Andrew Cooper
2016-02-16 10:06 ` Jan Beulich
2016-02-17 10:43 ` Andrew Cooper
2016-02-17 10:55 ` Jan Beulich
2016-02-17 14:02 ` Andrew Cooper
2016-02-17 14:45 ` Jan Beulich
2016-02-18 12:17 ` Andrew Cooper
2016-02-18 13:23 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 16/30] x86/cpu: Move set_cpumask() calls into c_early_init() Andrew Cooper
2016-02-16 14:10 ` Jan Beulich
2016-02-17 10:45 ` Andrew Cooper
2016-02-17 10:58 ` Jan Beulich
2016-02-18 12:41 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 17/30] x86/cpu: Common infrastructure for levelling context switching Andrew Cooper
2016-02-16 14:15 ` Jan Beulich
2016-02-17 8:15 ` Jan Beulich
2016-02-17 10:46 ` Andrew Cooper
2016-02-17 19:06 ` Konrad Rzeszutek Wilk
2016-02-05 13:42 ` [PATCH v2 18/30] x86/cpu: Rework AMD masking MSR setup Andrew Cooper
2016-02-17 7:40 ` Jan Beulich
2016-02-17 10:56 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 19/30] x86/cpu: Rework Intel masking/faulting setup Andrew Cooper
2016-02-17 7:57 ` Jan Beulich
2016-02-17 10:59 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 20/30] x86/cpu: Context switch cpuid masks and faulting state in context_switch() Andrew Cooper
2016-02-17 8:06 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 21/30] x86/pv: Provide custom cpumasks for PV domains Andrew Cooper
2016-02-17 8:13 ` Jan Beulich
2016-02-17 11:03 ` Andrew Cooper
2016-02-17 11:14 ` Jan Beulich
2016-02-18 12:48 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 22/30] x86/domctl: Update PV domain cpumasks when setting cpuid policy Andrew Cooper
2016-02-17 8:22 ` Jan Beulich
2016-02-17 12:13 ` Andrew Cooper
2016-02-05 13:42 ` [PATCH v2 23/30] xen+tools: Export maximum host and guest cpu featuresets via SYSCTL Andrew Cooper
2016-02-05 16:12 ` Wei Liu
2016-02-17 8:30 ` Jan Beulich
2016-02-17 12:17 ` Andrew Cooper
2016-02-17 12:23 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 24/30] tools/libxc: Modify bitmap operations to take void pointers Andrew Cooper
2016-02-05 16:12 ` Wei Liu
2016-02-08 11:40 ` Andrew Cooper
2016-02-08 16:23 ` Tim Deegan
2016-02-08 16:36 ` Ian Campbell
2016-02-10 10:07 ` Andrew Cooper
2016-02-10 10:18 ` Ian Campbell
2016-02-18 13:37 ` Andrew Cooper
2016-02-17 20:06 ` Konrad Rzeszutek Wilk [this message]
2016-02-05 13:42 ` [PATCH v2 25/30] tools/libxc: Use public/featureset.h for cpuid policy generation Andrew Cooper
2016-02-05 16:12 ` Wei Liu
2016-02-05 13:42 ` [PATCH v2 26/30] tools/libxc: Expose the automatically generated cpu featuremask information Andrew Cooper
2016-02-05 16:12 ` Wei Liu
2016-02-05 16:15 ` Wei Liu
2016-02-05 13:42 ` [PATCH v2 27/30] tools: Utility for dealing with featuresets Andrew Cooper
2016-02-05 16:13 ` Wei Liu
2016-02-05 13:42 ` [PATCH v2 28/30] tools/libxc: Wire a featureset through to cpuid policy logic Andrew Cooper
2016-02-05 16:13 ` Wei Liu
2016-02-05 13:42 ` [PATCH v2 29/30] tools/libxc: Use featuresets rather than guesswork Andrew Cooper
2016-02-05 16:13 ` Wei Liu
2016-02-17 8:55 ` Jan Beulich
2016-02-17 13:03 ` Andrew Cooper
2016-02-17 13:19 ` Jan Beulich
2016-02-05 13:42 ` [PATCH v2 30/30] tools/libxc: Calculate xstate cpuid leaf from guest information Andrew Cooper
2016-02-05 14:28 ` Jan Beulich
2016-02-05 15:22 ` Andrew Cooper
2016-02-08 17:26 ` [PATCH v2.5 31/30] Fix PV guest XSAVE handling with levelling Andrew Cooper
2016-02-17 9:02 ` Jan Beulich
2016-02-17 13:06 ` Andrew Cooper
2016-02-17 13:36 ` Jan Beulich
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160217200611.GL24109@char.us.oracle.com \
--to=konrad.wilk@oracle.com \
--cc=Ian.Jackson@eu.citrix.com \
--cc=andrew.cooper3@citrix.com \
--cc=ian.campbell@citrix.com \
--cc=tim@xen.org \
--cc=wei.liu2@citrix.com \
--cc=xen-devel@lists.xen.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).