From: Roger Pau Monne <roger.pau@citrix.com>
To: <xen-devel@lists.xenproject.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
Roger Pau Monne <roger.pau@citrix.com>,
Ian Jackson <iwj@xenproject.org>, Wei Liu <wl@xen.org>
Subject: [PATCH v3 03/13] libs/guest: allow fetching a specific MSR entry from a cpu policy
Date: Fri, 30 Apr 2021 17:52:01 +0200 [thread overview]
Message-ID: <20210430155211.3709-4-roger.pau@citrix.com> (raw)
In-Reply-To: <20210430155211.3709-1-roger.pau@citrix.com>
Introduce an interface that returns a specific MSR entry from a cpu
policy in xen_msr_entry_t format. Provide a helper to perform a binary
search against an array of MSR entries.
This is useful to callers can peek data from the opaque
xc_cpu_policy_t type.
No caller of the interface introduced on this patch.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
---
Changes since v1:
- Introduce a helper to perform a binary search of the MSR entries
array.
---
tools/include/xenctrl.h | 2 ++
tools/libs/guest/xg_cpuid_x86.c | 42 +++++++++++++++++++++++++++++++++
2 files changed, 44 insertions(+)
diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h
index cbca7209e34..605c632cf30 100644
--- a/tools/include/xenctrl.h
+++ b/tools/include/xenctrl.h
@@ -2611,6 +2611,8 @@ int xc_cpu_policy_serialise(xc_interface *xch, const xc_cpu_policy_t policy,
int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t policy,
uint32_t leaf, uint32_t subleaf,
xen_cpuid_leaf_t *out);
+int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t policy,
+ uint32_t msr, xen_msr_entry_t *out);
int xc_get_cpu_levelling_caps(xc_interface *xch, uint32_t *caps);
int xc_get_cpu_featureset(xc_interface *xch, uint32_t index,
diff --git a/tools/libs/guest/xg_cpuid_x86.c b/tools/libs/guest/xg_cpuid_x86.c
index de27826f415..9e83daca0e6 100644
--- a/tools/libs/guest/xg_cpuid_x86.c
+++ b/tools/libs/guest/xg_cpuid_x86.c
@@ -850,3 +850,45 @@ int xc_cpu_policy_get_cpuid(xc_interface *xch, const xc_cpu_policy_t policy,
*out = *tmp;
return 0;
}
+
+static int compare_entries(const void *l, const void *r)
+{
+ const xen_msr_entry_t *lhs = l;
+ const xen_msr_entry_t *rhs = r;
+
+ if ( lhs->idx == rhs->idx )
+ return 0;
+ return lhs->idx < rhs->idx ? -1 : 1;
+}
+
+static xen_msr_entry_t *find_entry(xen_msr_entry_t *entries,
+ unsigned int nr_entries, unsigned int index)
+{
+ const xen_msr_entry_t key = { index };
+
+ return bsearch(&key, entries, nr_entries, sizeof(*entries), compare_entries);
+}
+
+int xc_cpu_policy_get_msr(xc_interface *xch, const xc_cpu_policy_t policy,
+ uint32_t msr, xen_msr_entry_t *out)
+{
+ unsigned int nr_entries = ARRAY_SIZE(policy->entries);
+ xen_msr_entry_t *tmp;
+ int rc;
+
+ rc = xc_cpu_policy_serialise(xch, policy, NULL, 0,
+ policy->entries, &nr_entries);
+ if ( rc )
+ return rc;
+
+ tmp = find_entry(policy->entries, nr_entries, msr);
+ if ( !tmp )
+ {
+ /* Unable to find a matching MSR. */
+ errno = ENOENT;
+ return -1;
+ }
+
+ *out = *tmp;
+ return 0;
+}
--
2.31.1
next prev parent reply other threads:[~2021-04-30 15:54 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-04-30 15:51 [PATCH v3 00/13] libs/guest: new CPUID/MSR interface Roger Pau Monne
2021-04-30 15:51 ` [PATCH v3 01/13] libxl: don't ignore the return value from xc_cpuid_apply_policy Roger Pau Monne
2021-05-04 14:07 ` Anthony PERARD
2021-04-30 15:52 ` [PATCH v3 02/13] libs/guest: allow fetching a specific CPUID leaf from a cpu policy Roger Pau Monne
2021-05-04 11:59 ` Andrew Cooper
2021-05-04 13:47 ` Roger Pau Monné
2021-05-04 15:46 ` Andrew Cooper
2021-04-30 15:52 ` Roger Pau Monne [this message]
2021-05-03 10:41 ` [PATCH v3 03/13] libs/guest: allow fetching a specific MSR entry " Jan Beulich
2021-05-04 10:56 ` Roger Pau Monné
2021-05-04 11:40 ` Jan Beulich
2021-05-04 11:58 ` Roger Pau Monné
2021-05-04 17:11 ` Andrew Cooper
2021-05-05 7:38 ` Jan Beulich
2021-04-30 15:52 ` [PATCH v3 04/13] libs/guest: allow updating a cpu policy CPUID data Roger Pau Monne
2021-05-04 16:19 ` Andrew Cooper
2021-04-30 15:52 ` [PATCH v3 05/13] libs/guest: allow updating a cpu policy MSR data Roger Pau Monne
2021-05-04 16:20 ` Andrew Cooper
2021-04-30 15:52 ` [PATCH v3 06/13] libs/guest: introduce helper to check cpu policy compatibility Roger Pau Monne
2021-05-04 16:27 ` Andrew Cooper
2021-04-30 15:52 ` [PATCH v3 07/13] libs/guest: obtain a compatible cpu policy from two input ones Roger Pau Monne
2021-05-03 10:43 ` Jan Beulich
2021-05-04 11:56 ` Roger Pau Monné
2021-05-04 12:12 ` Jan Beulich
2021-05-04 16:50 ` Andrew Cooper
2021-04-30 15:52 ` [PATCH v3 08/13] libs/guest: make a cpu policy compatible with older Xen versions Roger Pau Monne
2021-05-03 11:09 ` Jan Beulich
2021-05-04 15:34 ` Roger Pau Monné
2021-05-05 7:42 ` Jan Beulich
2021-05-06 10:23 ` Roger Pau Monné
2021-05-06 10:52 ` Jan Beulich
2021-04-30 15:52 ` [PATCH v3 09/13] libs/guest: introduce helper set cpu topology in cpu policy Roger Pau Monne
2021-04-30 15:52 ` [PATCH v3 10/13] libs/guest: rework xc_cpuid_xend_policy Roger Pau Monne
2021-04-30 15:52 ` [PATCH v3 11/13] libs/guest: apply a featureset into a cpu policy Roger Pau Monne
2021-04-30 15:52 ` [PATCH v3 12/13] libs/{light,guest}: implement xc_cpuid_apply_policy in libxl Roger Pau Monne
2021-05-04 14:08 ` Anthony PERARD
2021-04-30 15:52 ` [PATCH v3 13/13] libs/guest: (re)move xc_cpu_policy_apply_cpuid Roger Pau Monne
2021-05-04 14:08 ` Anthony PERARD
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=20210430155211.3709-4-roger.pau@citrix.com \
--to=roger.pau@citrix.com \
--cc=andrew.cooper3@citrix.com \
--cc=iwj@xenproject.org \
--cc=wl@xen.org \
--cc=xen-devel@lists.xenproject.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).