From: "Jan Beulich" <JBeulich@suse.com>
To: xen-devel <xen-devel@lists.xenproject.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>, Keir Fraser <keir@xen.org>
Subject: [PATCH 2/2] x86/vMSI-X: add valid bits for read acceleration
Date: Fri, 20 Mar 2015 16:27:57 +0000 [thread overview]
Message-ID: <550C589D020000780006C2B2@mail.emea.novell.com> (raw)
In-Reply-To: <550C5065020000780006C27E@mail.emea.novell.com>
[-- Attachment #1: Type: text/plain, Size: 1817 bytes --]
Again because Xen doesn't get to see all guest writes, it shouldn't
serve reads from its cache before having seen a write to the respective
address.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/arch/x86/hvm/vmsi.c
+++ b/xen/arch/x86/hvm/vmsi.c
@@ -153,12 +153,15 @@ struct msixtbl_entry
/* TODO: resolve the potential race by destruction of pdev */
struct pci_dev *pdev;
unsigned long gtable; /* gpa of msix table */
- unsigned long table_flags[BITS_TO_LONGS(MAX_MSIX_TABLE_ENTRIES)];
+ DECLARE_BITMAP(table_flags, MAX_MSIX_TABLE_ENTRIES);
#define MAX_MSIX_ACC_ENTRIES 3
unsigned int table_len;
struct {
uint32_t msi_ad[3]; /* Shadow of address low, high and data */
} gentries[MAX_MSIX_ACC_ENTRIES];
+ DECLARE_BITMAP(acc_valid, 3 * MAX_MSIX_ACC_ENTRIES);
+#define acc_bit(what, ent, slot, idx) \
+ what##_bit((slot) * 3 + (idx), (ent)->acc_valid)
struct rcu_head rcu;
};
@@ -233,9 +236,10 @@ static int msixtbl_read(
if ( offset != PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET )
{
nr_entry = (address - entry->gtable) / PCI_MSIX_ENTRY_SIZE;
- if ( nr_entry >= MAX_MSIX_ACC_ENTRIES )
- goto out;
index = offset / sizeof(uint32_t);
+ if ( nr_entry >= MAX_MSIX_ACC_ENTRIES ||
+ !acc_bit(test, entry, nr_entry, index) )
+ goto out;
*pval = entry->gentries[nr_entry].msi_ad[index];
}
else
@@ -281,6 +285,7 @@ static int msixtbl_write(struct vcpu *v,
{
index = offset / sizeof(uint32_t);
entry->gentries[nr_entry].msi_ad[index] = val;
+ acc_bit(set, entry, nr_entry, index);
}
set_bit(nr_entry, &entry->table_flags);
goto out;
[-- Attachment #2: x86-vMSI-X-read-valid.patch --]
[-- Type: text/plain, Size: 1863 bytes --]
x86/vMSI-X: add valid bits for read acceleration
Again because Xen doesn't get to see all guest writes, it shouldn't
serve reads from its cache before having seen a write to the respective
address.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
--- a/xen/arch/x86/hvm/vmsi.c
+++ b/xen/arch/x86/hvm/vmsi.c
@@ -153,12 +153,15 @@ struct msixtbl_entry
/* TODO: resolve the potential race by destruction of pdev */
struct pci_dev *pdev;
unsigned long gtable; /* gpa of msix table */
- unsigned long table_flags[BITS_TO_LONGS(MAX_MSIX_TABLE_ENTRIES)];
+ DECLARE_BITMAP(table_flags, MAX_MSIX_TABLE_ENTRIES);
#define MAX_MSIX_ACC_ENTRIES 3
unsigned int table_len;
struct {
uint32_t msi_ad[3]; /* Shadow of address low, high and data */
} gentries[MAX_MSIX_ACC_ENTRIES];
+ DECLARE_BITMAP(acc_valid, 3 * MAX_MSIX_ACC_ENTRIES);
+#define acc_bit(what, ent, slot, idx) \
+ what##_bit((slot) * 3 + (idx), (ent)->acc_valid)
struct rcu_head rcu;
};
@@ -233,9 +236,10 @@ static int msixtbl_read(
if ( offset != PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET )
{
nr_entry = (address - entry->gtable) / PCI_MSIX_ENTRY_SIZE;
- if ( nr_entry >= MAX_MSIX_ACC_ENTRIES )
- goto out;
index = offset / sizeof(uint32_t);
+ if ( nr_entry >= MAX_MSIX_ACC_ENTRIES ||
+ !acc_bit(test, entry, nr_entry, index) )
+ goto out;
*pval = entry->gentries[nr_entry].msi_ad[index];
}
else
@@ -281,6 +285,7 @@ static int msixtbl_write(struct vcpu *v,
{
index = offset / sizeof(uint32_t);
entry->gentries[nr_entry].msi_ad[index] = val;
+ acc_bit(set, entry, nr_entry, index);
}
set_bit(nr_entry, &entry->table_flags);
goto out;
[-- Attachment #3: Type: text/plain, Size: 126 bytes --]
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next prev parent reply other threads:[~2015-03-20 16:28 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-03-20 15:52 [PATCH 0/2] x86/vMSI-X: table read/write emulation adjustments Jan Beulich
2015-03-20 16:27 ` [PATCH 1/2] x86/vMSI-X: honor all mask requests Jan Beulich
2015-03-23 19:15 ` Konrad Rzeszutek Wilk
2015-03-25 5:40 ` Wu, Feng
2015-03-25 5:49 ` Wu, Feng
2015-03-25 10:36 ` Jan Beulich
2015-04-14 14:17 ` Andrew Cooper
2015-03-20 16:27 ` Jan Beulich [this message]
2015-03-23 19:11 ` [PATCH 2/2] x86/vMSI-X: add valid bits for read acceleration Konrad Rzeszutek Wilk
2015-03-24 7:49 ` Jan Beulich
2015-04-14 14:37 ` Andrew Cooper
2015-04-14 10:11 ` Ping: [PATCH 0/2] x86/vMSI-X: table read/write emulation adjustments Jan Beulich
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