[PATCH v5 2/7] x86/msi: Extend per-domain/device warning mechanism - Marek Marczykowski-Górecki

From: "Marek Marczykowski-Górecki" <marmarek@invisiblethingslab.com>
To: xen-devel@lists.xenproject.org
Cc: "Marek Marczykowski-Górecki" <marmarek@invisiblethingslab.com>,
	"Jan Beulich" <jbeulich@suse.com>,
	"Andrew Cooper" <andrew.cooper3@citrix.com>,
	"Roger Pau Monné" <roger.pau@citrix.com>, "Wei Liu" <wl@xen.org>
Subject: [PATCH v5 2/7] x86/msi: Extend per-domain/device warning mechanism
Date: Wed, 13 Mar 2024 16:16:07 +0100	[thread overview]
Message-ID: <ec68ca290a207a3e191e470fb19254b7f6f887f8.1710342968.git-series.marmarek@invisiblethingslab.com> (raw)
In-Reply-To: <cover.afa2d89161590f5193dd6bfd340c5e9347877aae.1710342968.git-series.marmarek@invisiblethingslab.com>

The arch_msix struct had a single "warned" field with a domid for which
warning was issued. Upcoming patch will need similar mechanism for few
more warnings, so change it to save a bit field of issued warnings.

Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
Should I add also some helper for the boilerplate the handling requires
now? I tried some macro that also sets the bit field, but I couldn't get
it working. I guess I could make it working with a bitmask in a single
uint8_t - would that be preferred?

New in v5
---
 xen/arch/x86/include/asm/msi.h |  8 +++++++-
 xen/arch/x86/msi.c             |  9 +++++++--
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/include/asm/msi.h b/xen/arch/x86/include/asm/msi.h
index 997ccb87be0c..19b1e6631fdf 100644
--- a/xen/arch/x86/include/asm/msi.h
+++ b/xen/arch/x86/include/asm/msi.h
@@ -217,7 +217,13 @@ struct arch_msix {
     int table_idx[MAX_MSIX_TABLE_PAGES];
     spinlock_t table_lock;
     bool host_maskall, guest_maskall;
-    domid_t warned;
+    domid_t warned_domid;
+    union {
+        uint8_t all;
+        struct {
+            bool maskall                   : 1;
+        } u;
+    } warned_kind;
 };
 
 void early_msi_init(void);
diff --git a/xen/arch/x86/msi.c b/xen/arch/x86/msi.c
index e721aaf5c001..6433df30bd60 100644
--- a/xen/arch/x86/msi.c
+++ b/xen/arch/x86/msi.c
@@ -364,9 +364,14 @@ static bool msi_set_mask_bit(struct irq_desc *desc, bool host, bool guest)
             domid_t domid = pdev->domain->domain_id;
 
             maskall = true;
-            if ( pdev->msix->warned != domid )
+            if ( pdev->msix->warned_domid != domid )
             {
-                pdev->msix->warned = domid;
+                pdev->msix->warned_domid = domid;
+                pdev->msix->warned_kind.all = 0;
+            }
+            if ( !pdev->msix->warned_kind.u.maskall )
+            {
+                pdev->msix->warned_kind.u.maskall = true;
                 printk(XENLOG_G_WARNING
                        "cannot mask IRQ %d: masking MSI-X on Dom%d's %pp\n",
                        desc->irq, domid, &pdev->sbdf);
-- 
git-series 0.9.1

