From: Jan Beulich <jbeulich@suse.com>
To: Roger Pau Monne <roger.pau@citrix.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>,
Ian Jackson <iwj@xenproject.org>, Wei Liu <wl@xen.org>,
xen-devel@lists.xenproject.org
Subject: Re: [PATCH 04/21] libs/guest: introduce helper to fetch a system cpu policy
Date: Tue, 30 Mar 2021 17:35:25 +0200 [thread overview]
Message-ID: <6d30e100-3321-a8bd-26bf-38d78d522637@suse.com> (raw)
In-Reply-To: <20210323095849.37858-5-roger.pau@citrix.com>
On 23.03.2021 10:58, Roger Pau Monne wrote:
> Such helper is based on the existing functions to fetch a CPUID and
> MSR policies, but uses the xc_cpu_policy_t type to return the data to
> the caller.
>
> Note some helper functions are introduced, those are split from
> xc_cpu_policy_get_system because they will be used by other functions
> also.
>
> No user of the interface introduced on the patch.
>
> Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
with just one minor remark below:
> --- a/tools/include/xenctrl.h
> +++ b/tools/include/xenctrl.h
> @@ -2596,6 +2596,10 @@ typedef struct cpu_policy *xc_cpu_policy_t;
> xc_cpu_policy_t xc_cpu_policy_init(void);
> void xc_cpu_policy_destroy(xc_cpu_policy_t policy);
>
> +/* Retrieve a system policy, or get/set a domains policy. */
> +int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
> + xc_cpu_policy_t policy);
> +
> int xc_get_cpu_levelling_caps(xc_interface *xch, uint32_t *caps);
> int xc_get_cpu_featureset(xc_interface *xch, uint32_t index,
> uint32_t *nr_features, uint32_t *featureset);
> diff --git a/tools/libs/guest/xg_cpuid_x86.c b/tools/libs/guest/xg_cpuid_x86.c
> index ade5281c178..3710fb63839 100644
> --- a/tools/libs/guest/xg_cpuid_x86.c
> +++ b/tools/libs/guest/xg_cpuid_x86.c
> @@ -687,3 +687,93 @@ void xc_cpu_policy_destroy(xc_cpu_policy_t policy)
> free(policy->msr);
> free(policy);
> }
> +
> +static int allocate_buffers(xc_interface *xch,
> + unsigned int *nr_leaves, xen_cpuid_leaf_t **leaves,
> + unsigned int *nr_msrs, xen_msr_entry_t **msrs)
> +{
> + int rc;
> +
> + *leaves = NULL;
> + *msrs = NULL;
> +
> + rc = xc_cpu_policy_get_size(xch, nr_leaves, nr_msrs);
> + if ( rc )
> + {
> + PERROR("Failed to obtain policy info size");
> + return -errno;
> + }
> +
> + *leaves = calloc(*nr_leaves, sizeof(**leaves));
> + *msrs = calloc(*nr_msrs, sizeof(**msrs));
> + if ( !*leaves || !*msrs )
> + {
> + PERROR("Failed to allocate resources");
> + free(*leaves);
> + free(*msrs);
> + return -ENOMEM;
> + }
> +
> + return 0;
> +}
> +
> +static int deserialize_policy(xc_interface *xch, xc_cpu_policy_t policy,
> + unsigned int nr_leaves,
> + const xen_cpuid_leaf_t *leaves,
> + unsigned int nr_msrs, const xen_msr_entry_t *msrs)
> +{
> + uint32_t err_leaf = -1, err_subleaf = -1, err_msr = -1;
> + int rc;
> +
> + rc = x86_cpuid_copy_from_buffer(policy->cpuid, leaves, nr_leaves,
> + &err_leaf, &err_subleaf);
> + if ( rc )
> + {
> + ERROR("Failed to deserialise CPUID (err leaf %#x, subleaf %#x) (%d = %s)",
> + err_leaf, err_subleaf, -rc, strerror(-rc));
> + return rc;
> + }
> +
> + rc = x86_msr_copy_from_buffer(policy->msr, msrs, nr_msrs, &err_msr);
> + if ( rc )
> + {
> + ERROR("Failed to deserialise MSR (err MSR %#x) (%d = %s)",
> + err_msr, -rc, strerror(-rc));
> + return rc;
> + }
> +
> + return 0;
> +}
> +
> +int xc_cpu_policy_get_system(xc_interface *xch, unsigned int idx,
> + xc_cpu_policy_t policy)
> +{
> + unsigned int nr_leaves, nr_msrs;
> + xen_cpuid_leaf_t *leaves = NULL;
> + xen_msr_entry_t *msrs = NULL;
> + int rc;
> +
> + rc = allocate_buffers(xch, &nr_leaves, &leaves, &nr_msrs, &msrs);
> + if ( rc )
> + {
> + errno = -rc;
> + return -1;
> + }
> +
> + rc = xc_get_system_cpu_policy(xch, idx, &nr_leaves, leaves, &nr_msrs, msrs);
> + if ( rc )
> + {
> + PERROR("Failed to obtain %u policy", idx);
> + rc = -1;
> + goto out;
> + }
> +
> + rc = deserialize_policy(xch, policy, nr_leaves, leaves, nr_msrs, msrs);
> + if ( rc )
> + errno = -rc;
Perhaps also set rc to -1 here for consistency?
Jan
next prev parent reply other threads:[~2021-03-30 15:35 UTC|newest]
Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-23 9:58 [PATCH 00/21] libs/guest: new CPUID/MSR interface Roger Pau Monne
2021-03-23 9:58 ` [PATCH 01/21] libxl: don't ignore the return value from xc_cpuid_apply_policy Roger Pau Monne
2021-03-30 15:21 ` Jan Beulich
2021-03-30 15:38 ` Andrew Cooper
2021-03-31 18:12 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 02/21] libs/guest: rename xc_get_cpu_policy_size to xc_cpu_policy_get_size Roger Pau Monne
2021-03-31 19:03 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 03/21] libs/guest: introduce xc_cpu_policy_t Roger Pau Monne
2021-03-31 20:10 ` Andrew Cooper
2021-04-01 8:48 ` Roger Pau Monné
2021-03-23 9:58 ` [PATCH 04/21] libs/guest: introduce helper to fetch a system cpu policy Roger Pau Monne
2021-03-30 15:35 ` Jan Beulich [this message]
2021-04-01 13:56 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 05/21] libs/guest: introduce helper to fetch a domain " Roger Pau Monne
2021-03-30 15:37 ` Jan Beulich
2021-03-31 11:06 ` Roger Pau Monné
2021-04-01 13:32 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 06/21] libs/guest: introduce helper to serialize a " Roger Pau Monne
2021-03-23 9:58 ` [PATCH 07/21] tools: switch existing users of xc_get_{system,domain}_cpu_policy Roger Pau Monne
2021-03-23 9:58 ` [PATCH 08/21] libs/guest: introduce a helper to apply a cpu policy to a domain Roger Pau Monne
2021-03-23 9:58 ` [PATCH 09/21] libs/guest: allow fetching a specific CPUID leaf from a cpu policy Roger Pau Monne
2021-04-01 14:47 ` Andrew Cooper
2021-04-08 15:53 ` Roger Pau Monné
2021-03-23 9:58 ` [PATCH 10/21] libs/guest: allow fetching a specific MSR entry " Roger Pau Monne
2021-03-23 9:58 ` [PATCH 11/21] libs/guest: allow updating a cpu policy CPUID data Roger Pau Monne
2021-03-30 15:56 ` Jan Beulich
2021-03-31 12:47 ` Roger Pau Monné
2021-04-01 14:55 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 12/21] libs/guest: allow updating a cpu policy MSR data Roger Pau Monne
2021-03-23 9:58 ` [PATCH 13/21] libs/guest: switch users of xc_set_domain_cpu_policy Roger Pau Monne
2021-04-01 15:04 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 14/21] libs/guest: introduce helper to check cpu policy compatibility Roger Pau Monne
2021-03-30 16:02 ` Jan Beulich
2021-03-31 12:40 ` Roger Pau Monné
2021-03-31 14:57 ` Jan Beulich
2021-04-01 16:14 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 15/21] libs/guest: obtain a compatible cpu policy from two input ones Roger Pau Monne
2021-03-31 15:24 ` Jan Beulich
2021-04-01 16:26 ` Andrew Cooper
2021-04-09 10:56 ` Roger Pau Monné
2021-03-23 9:58 ` [PATCH 16/21] libs/guest: make a cpu policy compatible with older Xen versions Roger Pau Monne
2021-03-31 15:29 ` Jan Beulich
2021-04-01 16:31 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 17/21] libs/guest: introduce helper set cpu topology in cpu policy Roger Pau Monne
2021-04-01 17:22 ` Andrew Cooper
2021-03-23 9:58 ` [PATCH 18/21] libs/guest: rework xc_cpuid_xend_policy Roger Pau Monne
2021-03-23 9:58 ` [PATCH 19/21] libs/guest: apply a featureset into a cpu policy Roger Pau Monne
2021-03-23 9:58 ` [PATCH 20/21] libs/{light,guest}: implement xc_cpuid_apply_policy in libxl Roger Pau Monne
2021-04-01 17:44 ` Andrew Cooper
2021-04-09 14:57 ` Roger Pau Monné
2021-03-23 9:58 ` [PATCH 21/21] libs/guest: (re)move xc_cpu_policy_apply_cpuid Roger Pau Monne
2021-04-01 17:53 ` Andrew Cooper
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