[PATCH v2 0/3] argo: few loglevel fixes

[PATCH v2 0/3] argo: few loglevel fixes

[dmukhin]

This mini-series fixes a few log messages in the Argo module.

Patch 1 lowers the verbosity of a spammy log message.
Patch 2 corrects the debug logline.
Patch 3 cleans up existing loglines by dropping duplicate prefixes.

CI: https://gitlab.com/xen-project/people/dmukhin/xen/-/pipelines/2546842322

Denis Mukhin (3):
  argo: lower level of noisy connection-refused log
  argo: correct logline in ring_unmap()
  argo: drop argo prefix from argo_dprintk() calls

 xen/common/argo.c | 17 ++++++++---------
 1 file changed, 8 insertions(+), 9 deletions(-)

-- 
2.54.0

[PATCH v2 1/3] argo: lower level of noisy connection-refused log

[dmukhin]

From: Denis Mukhin <dmukhin@ford.com> 

Lower the log level of the "connection refused" log line, as it can
spam the logs when a dom0 service using the Argo hypercall tries to
communicate with a domain that is still starting up.

Signed-off-by: Denis Mukhin <dmukhin@ford.com>
---
Changes since v1:
- dropped duplicate "argo: " prefix
---
 xen/common/argo.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/xen/common/argo.c b/xen/common/argo.c
index 28626e00a8cb..98a3db7fd070 100644
--- a/xen/common/argo.c
+++ b/xen/common/argo.c
@@ -2034,10 +2034,9 @@ sendv(struct domain *src_d, xen_argo_addr_t *src_addr,
                                         src_id.domain_id);
     if ( !ring_info )
     {
-        gprintk(XENLOG_ERR,
-                "argo: vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
-                current->domain->domain_id, src_id.domain_id, src_id.aport,
-                dst_addr->domain_id, dst_addr->aport);
+        argo_dprintk("vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
+                     current->domain->domain_id, src_id.domain_id, src_id.aport,
+                     dst_addr->domain_id, dst_addr->aport);
 
         ret = -ECONNREFUSED;
     }
-- 
2.54.0

[PATCH v2 2/3] argo: correct logline in ring_unmap()

[dmukhin]

From: Denis Mukhin <dmukhin@ford.com> 

Drop XENLOG_ERR from the logline since argo_dprintk() already injects
the proper log level indicator.

Also, drop "argo: " prefix, since it is also injected by argo_dprintk()

Signed-off-by: Denis Mukhin <dmukhin@ford.com>
---
Changes since v1:
- dropped duplicate "argo: " prefix
---
 xen/common/argo.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/xen/common/argo.c b/xen/common/argo.c
index 98a3db7fd070..5da14c929e14 100644
--- a/xen/common/argo.c
+++ b/xen/common/argo.c
@@ -474,7 +474,7 @@ ring_unmap(const struct domain *d, struct argo_ring_info *ring_info)
             continue;
 
         ASSERT(!mfn_eq(ring_info->mfns[i], INVALID_MFN));
-        argo_dprintk(XENLOG_ERR "argo: unmapping page %"PRI_mfn" from %p\n",
+        argo_dprintk("unmapping page %"PRI_mfn" from %p\n",
                      mfn_x(ring_info->mfns[i]), ring_info->mfn_mapping[i]);
 
         unmap_domain_page_global(ring_info->mfn_mapping[i]);
-- 
2.54.0

[PATCH v2 3/3] argo: drop argo prefix from argo_dprintk() calls

[dmukhin]

From: Denis Mukhin <dmukhin@ford.com> 

argo_dprintk() prefixes all log lines with "argo: " automatically.

Remove duplicate prefixes from log messages in the Argo module where
applicable.

Signed-off-by: Denis Mukhin <dmukhin@ford.com>
---
Changes since v1:
- new patch
---
 xen/common/argo.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/xen/common/argo.c b/xen/common/argo.c
index 5da14c929e14..ffa1f43437ab 100644
--- a/xen/common/argo.c
+++ b/xen/common/argo.c
@@ -1467,7 +1467,7 @@ find_ring_mfns(struct domain *d, struct argo_ring_info *ring_info,
     if ( ring_info->mfns )
     {
         /* Ring already existed: drop the previous mapping. */
-        argo_dprintk("argo: vm%u re-register existing ring "
+        argo_dprintk("vm%u re-register existing ring "
                      "(vm%u:%x vm%u) clears mapping\n",
                      d->domain_id, ring_info->id.domain_id,
                      ring_info->id.aport, ring_info->id.partner_id);
@@ -1527,7 +1527,7 @@ find_ring_mfns(struct domain *d, struct argo_ring_info *ring_info,
     {
         ASSERT(ring_info->nmfns == NPAGES_RING(len));
 
-        argo_dprintk("argo: vm%u ring (vm%u:%x vm%u) %p "
+        argo_dprintk("vm%u ring (vm%u:%x vm%u) %p "
                      "mfn_mapping %p len %u nmfns %u\n",
                      d->domain_id, ring_info->id.domain_id,
                      ring_info->id.aport, ring_info->id.partner_id, ring_info,
@@ -1741,7 +1741,7 @@ register_ring(struct domain *currd,
         list_add(&ring_info->node,
                  &currd->argo->ring_hash[hash_index(&ring_info->id)]);
 
-        argo_dprintk("argo: vm%u registering ring (vm%u:%x vm%u)\n",
+        argo_dprintk("vm%u registering ring (vm%u:%x vm%u)\n",
                      currd->domain_id, ring_id.domain_id, ring_id.aport,
                      ring_id.partner_id);
     }
@@ -1781,7 +1781,7 @@ register_ring(struct domain *currd,
             goto out_unlock2;
         }
 
-        argo_dprintk("argo: vm%u re-registering existing ring (vm%u:%x vm%u)\n",
+        argo_dprintk("vm%u re-registering existing ring (vm%u:%x vm%u)\n",
                      currd->domain_id, ring_id.domain_id, ring_id.aport,
                      ring_id.partner_id);
     }
-- 
2.54.0

Re: [PATCH v2 1/3] argo: lower level of noisy connection-refused log

[Mykola Kvach]

On Fri, May 22, 2026 at 7:53 PM <dmukhin@ford.com> wrote:
>
> From: Denis Mukhin <dmukhin@ford.com>
>
> Lower the log level of the "connection refused" log line, as it can
> spam the logs when a dom0 service using the Argo hypercall tries to
> communicate with a domain that is still starting up.
>
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v1:
> - dropped duplicate "argo: " prefix
> ---
>  xen/common/argo.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/xen/common/argo.c b/xen/common/argo.c
> index 28626e00a8cb..98a3db7fd070 100644
> --- a/xen/common/argo.c
> +++ b/xen/common/argo.c
> @@ -2034,10 +2034,9 @@ sendv(struct domain *src_d, xen_argo_addr_t *src_addr,
>                                          src_id.domain_id);
>      if ( !ring_info )
>      {
> -        gprintk(XENLOG_ERR,
> -                "argo: vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
> -                current->domain->domain_id, src_id.domain_id, src_id.aport,
> -                dst_addr->domain_id, dst_addr->aport);
> +        argo_dprintk("vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
> +                     current->domain->domain_id, src_id.domain_id, src_id.aport,
> +                     dst_addr->domain_id, dst_addr->aport);
>
>          ret = -ECONNREFUSED;
>      }
> --
> 2.54.0
>
>

Reviewed-by: Mykola Kvach <mykola_kvach@epam.com>

~Mykola

Re: [PATCH v2 2/3] argo: correct logline in ring_unmap()

[Mykola Kvach]

On Fri, May 22, 2026 at 7:53 PM <dmukhin@ford.com> wrote:
>
> From: Denis Mukhin <dmukhin@ford.com>
>
> Drop XENLOG_ERR from the logline since argo_dprintk() already injects
> the proper log level indicator.
>
> Also, drop "argo: " prefix, since it is also injected by argo_dprintk()
>
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v1:
> - dropped duplicate "argo: " prefix
> ---
>  xen/common/argo.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/xen/common/argo.c b/xen/common/argo.c
> index 98a3db7fd070..5da14c929e14 100644
> --- a/xen/common/argo.c
> +++ b/xen/common/argo.c
> @@ -474,7 +474,7 @@ ring_unmap(const struct domain *d, struct argo_ring_info *ring_info)
>              continue;
>
>          ASSERT(!mfn_eq(ring_info->mfns[i], INVALID_MFN));
> -        argo_dprintk(XENLOG_ERR "argo: unmapping page %"PRI_mfn" from %p\n",
> +        argo_dprintk("unmapping page %"PRI_mfn" from %p\n",
>                       mfn_x(ring_info->mfns[i]), ring_info->mfn_mapping[i]);

Reviewed-by: Mykola Kvach <mykola_kvach@epam.com>

~Mykola

Re: [PATCH v2 3/3] argo: drop argo prefix from argo_dprintk() calls

[Mykola Kvach]

On Fri, May 22, 2026 at 7:53 PM <dmukhin@ford.com> wrote:
>
> From: Denis Mukhin <dmukhin@ford.com>
>
> argo_dprintk() prefixes all log lines with "argo: " automatically.
>
> Remove duplicate prefixes from log messages in the Argo module where
> applicable.
>
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v1:
> - new patch
> ---
>  xen/common/argo.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/xen/common/argo.c b/xen/common/argo.c
> index 5da14c929e14..ffa1f43437ab 100644
> --- a/xen/common/argo.c
> +++ b/xen/common/argo.c
> @@ -1467,7 +1467,7 @@ find_ring_mfns(struct domain *d, struct argo_ring_info *ring_info,
>      if ( ring_info->mfns )
>      {
>          /* Ring already existed: drop the previous mapping. */
> -        argo_dprintk("argo: vm%u re-register existing ring "
> +        argo_dprintk("vm%u re-register existing ring "
>                       "(vm%u:%x vm%u) clears mapping\n",
>                       d->domain_id, ring_info->id.domain_id,
>                       ring_info->id.aport, ring_info->id.partner_id);
> @@ -1527,7 +1527,7 @@ find_ring_mfns(struct domain *d, struct argo_ring_info *ring_info,
>      {
>          ASSERT(ring_info->nmfns == NPAGES_RING(len));
>
> -        argo_dprintk("argo: vm%u ring (vm%u:%x vm%u) %p "
> +        argo_dprintk("vm%u ring (vm%u:%x vm%u) %p "
>                       "mfn_mapping %p len %u nmfns %u\n",
>                       d->domain_id, ring_info->id.domain_id,
>                       ring_info->id.aport, ring_info->id.partner_id, ring_info,
> @@ -1741,7 +1741,7 @@ register_ring(struct domain *currd,
>          list_add(&ring_info->node,
>                   &currd->argo->ring_hash[hash_index(&ring_info->id)]);
>
> -        argo_dprintk("argo: vm%u registering ring (vm%u:%x vm%u)\n",
> +        argo_dprintk("vm%u registering ring (vm%u:%x vm%u)\n",
>                       currd->domain_id, ring_id.domain_id, ring_id.aport,
>                       ring_id.partner_id);
>      }
> @@ -1781,7 +1781,7 @@ register_ring(struct domain *currd,
>              goto out_unlock2;
>          }
>
> -        argo_dprintk("argo: vm%u re-registering existing ring (vm%u:%x vm%u)\n",
> +        argo_dprintk("vm%u re-registering existing ring (vm%u:%x vm%u)\n",
>                       currd->domain_id, ring_id.domain_id, ring_id.aport,
>                       ring_id.partner_id);

Reviewed-by: Mykola Kvach <mykola_kvach@epam.com>

~Mykola

Re: [PATCH v2 1/3] argo: lower level of noisy connection-refused log

[Mykola Kvach]

Hi Denis,

Just one follow-up after sending my Reviewed-by.

The patches look fine to me and my tag still stands, but there are a
couple of side effects worth considering here.

On Fri, May 22, 2026 at 7:53 PM <dmukhin@ford.com> wrote:
>
> From: Denis Mukhin <dmukhin@ford.com>
>
> Lower the log level of the "connection refused" log line, as it can
> spam the logs when a dom0 service using the Argo hypercall tries to
> communicate with a domain that is still starting up.
>
> Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> ---
> Changes since v1:
> - dropped duplicate "argo: " prefix
> ---
>  xen/common/argo.c | 7 +++----
>  1 file changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/xen/common/argo.c b/xen/common/argo.c
> index 28626e00a8cb..98a3db7fd070 100644
> --- a/xen/common/argo.c
> +++ b/xen/common/argo.c
> @@ -2034,10 +2034,9 @@ sendv(struct domain *src_d, xen_argo_addr_t *src_addr,
>                                          src_id.domain_id);
>      if ( !ring_info )
>      {
> -        gprintk(XENLOG_ERR,
> -                "argo: vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
> -                current->domain->domain_id, src_id.domain_id, src_id.aport,
> -                dst_addr->domain_id, dst_addr->aport);
> +        argo_dprintk("vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",

First, switching from gprintk() to argo_dprintk() means the message will
no longer include the "%pv" context printed by gprintk(), i.e. the
current vCPU/domain context. If that context is still useful for this
message, it may need to be added explicitly.

Second, this also changes when the message is printed. gprintk() is a
regular printk() wrapper with a guest prefix and the requested log level,
while argo_dprintk() is compiled as a no-op unless ARGO_DEBUG is enabled.
So the change is not only lowering the log level from error to debug, but
also making the message depend on ARGO_DEBUG.

This may be intended, but in that case it might be worth mentioning this
in the commit message.

~Mykola

Re: [PATCH v2 1/3] argo: lower level of noisy connection-refused log

[dmukhin]

On Fri, May 22, 2026 at 08:36:58PM +0300, Mykola Kvach wrote:
> Hi Denis,
> 
> Just one follow-up after sending my Reviewed-by.
> 
> The patches look fine to me and my tag still stands, but there are a
> couple of side effects worth considering here.
> 
> On Fri, May 22, 2026 at 7:53 PM <dmukhin@ford.com> wrote:
> >
> > From: Denis Mukhin <dmukhin@ford.com>
> >
> > Lower the log level of the "connection refused" log line, as it can
> > spam the logs when a dom0 service using the Argo hypercall tries to
> > communicate with a domain that is still starting up.
> >
> > Signed-off-by: Denis Mukhin <dmukhin@ford.com>
> > ---
> > Changes since v1:
> > - dropped duplicate "argo: " prefix
> > ---
> >  xen/common/argo.c | 7 +++----
> >  1 file changed, 3 insertions(+), 4 deletions(-)
> >
> > diff --git a/xen/common/argo.c b/xen/common/argo.c
> > index 28626e00a8cb..98a3db7fd070 100644
> > --- a/xen/common/argo.c
> > +++ b/xen/common/argo.c
> > @@ -2034,10 +2034,9 @@ sendv(struct domain *src_d, xen_argo_addr_t *src_addr,
> >                                          src_id.domain_id);
> >      if ( !ring_info )
> >      {
> > -        gprintk(XENLOG_ERR,
> > -                "argo: vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
> > -                current->domain->domain_id, src_id.domain_id, src_id.aport,
> > -                dst_addr->domain_id, dst_addr->aport);
> > +        argo_dprintk("vm%u connection refused, src (vm%u:%x) dst (vm%u:%x)\n",
> 
> First, switching from gprintk() to argo_dprintk() means the message will
> no longer include the "%pv" context printed by gprintk(), i.e. the
> current vCPU/domain context. If that context is still useful for this
> message, it may need to be added explicitly.

I think %pv context is useful for debugging, I will add another small
patch to re-wire argo_dprintk() to gprintk().

> 
> Second, this also changes when the message is printed. gprintk() is a
> regular printk() wrapper with a guest prefix and the requested log level,
> while argo_dprintk() is compiled as a no-op unless ARGO_DEBUG is enabled.
> So the change is not only lowering the log level from error to debug, but
> also making the message depend on ARGO_DEBUG.
> 
> This may be intended, but in that case it might be worth mentioning this
> in the commit message.

Yes, this specific logline should be fine to be compiled out, the error
is propaged back to the caller domain via XEN_ARGO_OP_sendv hypercall.

I will update the commit message.

Thanks!

> 
> ~Mykola
>