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[Qemu-devel] [PULL v2 19/40] ivshmem: Clean up MSI-X conditions
From: |
Markus Armbruster |
Subject: |
[Qemu-devel] [PULL v2 19/40] ivshmem: Clean up MSI-X conditions |
Date: |
Mon, 21 Mar 2016 21:43:42 +0100 |
There are three predicates related to MSI-X:
* ivshmem_has_feature(s, IVSHMEM_MSI) is true unless the non-MSI-X
variant of the device is selected with msi=off.
* msix_present() is true when the device has the PCI capability MSI-X.
It's initially false, and becomes true during successful realize of
the MSI-X variant of the device. Thus, it's the same as
ivshmem_has_feature(s, IVSHMEM_MSI) for realized devices.
* msix_enabled() is true when msix_present() is true and guest software
has enabled MSI-X.
Code that differs between the non-MSI-X and the MSI-X variant of the
device needs to be guarded by ivshmem_has_feature(s, IVSHMEM_MSI) or
by msix_present(), except the latter works only for realized devices.
Code that depends on whether MSI-X is in use needs to be guarded with
msix_enabled().
Code review led me to two minor messes:
* ivshmem_vector_notify() calls msix_notify() even when
!msix_enabled(), unlike most other MSI-X-capable devices. As far as
I can tell, msix_notify() does nothing when !msix_enabled(). Add
the guard anyway.
* Most callers of ivshmem_use_msix() guard it with
ivshmem_has_feature(s, IVSHMEM_MSI). Not necessary, because
ivshmem_use_msix() does nothing when !msix_present(). That's
ivshmem's only use of msix_present(), though. Guard it
consistently, and drop the now redundant msix_present() check.
While there, rename ivshmem_use_msix() to ivshmem_msix_vector_use().
Signed-off-by: Markus Armbruster <address@hidden>
Message-Id: <address@hidden>
Reviewed-by: Marc-André Lureau <address@hidden>
---
hw/misc/ivshmem.c | 22 ++++++++++------------
1 file changed, 10 insertions(+), 12 deletions(-)
diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 1debce3..abcb1c1 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -274,7 +274,9 @@ static void ivshmem_vector_notify(void *opaque)
IVSHMEM_DPRINTF("interrupt on vector %p %d\n", pdev, vector);
if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
- msix_notify(pdev, vector);
+ if (msix_enabled(pdev)) {
+ msix_notify(pdev, vector);
+ }
} else {
ivshmem_IntrStatus_write(s, 1);
}
@@ -713,16 +715,11 @@ static void ivshmem_check_version(void *opaque, const
uint8_t * buf, int size)
/* Select the MSI-X vectors used by device.
* ivshmem maps events to vectors statically, so
* we just enable all vectors on init and after reset. */
-static void ivshmem_use_msix(IVShmemState * s)
+static void ivshmem_msix_vector_use(IVShmemState *s)
{
PCIDevice *d = PCI_DEVICE(s);
int i;
- IVSHMEM_DPRINTF("%s, msix present: %d\n", __func__, msix_present(d));
- if (!msix_present(d)) {
- return;
- }
-
for (i = 0; i < s->vectors; i++) {
msix_vector_use(d, i);
}
@@ -734,7 +731,9 @@ static void ivshmem_reset(DeviceState *d)
s->intrstatus = 0;
s->intrmask = 0;
- ivshmem_use_msix(s);
+ if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
+ ivshmem_msix_vector_use(s);
+ }
}
static int ivshmem_setup_interrupts(IVShmemState *s)
@@ -748,7 +747,7 @@ static int ivshmem_setup_interrupts(IVShmemState *s)
}
IVSHMEM_DPRINTF("msix initialized (%d vectors)\n", s->vectors);
- ivshmem_use_msix(s);
+ ivshmem_msix_vector_use(s);
}
return 0;
@@ -1040,9 +1039,8 @@ static int ivshmem_post_load(void *opaque, int version_id)
IVShmemState *s = opaque;
if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
- ivshmem_use_msix(s);
+ ivshmem_msix_vector_use(s);
}
-
return 0;
}
@@ -1070,7 +1068,7 @@ static int ivshmem_load_old(QEMUFile *f, void *opaque,
int version_id)
if (ivshmem_has_feature(s, IVSHMEM_MSI)) {
msix_load(pdev, f);
- ivshmem_use_msix(s);
+ ivshmem_msix_vector_use(s);
} else {
s->intrstatus = qemu_get_be32(f);
s->intrmask = qemu_get_be32(f);
--
2.4.3
- [Qemu-devel] [PULL v2 20/40] ivshmem: Leave INTx alone when using MSI-X, (continued)
- [Qemu-devel] [PULL v2 20/40] ivshmem: Leave INTx alone when using MSI-X, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 27/40] ivshmem: Rely on server sending the ID right after the version, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 29/40] ivshmem: Simplify how we cope with short reads from server, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 31/40] ivshmem: Implement shm=... with a memory backend, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 35/40] ivshmem: Replace int role_val by OnOffAuto master, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 01/40] target-ppc: Document TOCTTOU in hugepage support, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 25/40] ivshmem: Receive shared memory synchronously in realize(), Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 10/40] ivshmem: Rewrite specification document, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 39/40] ivshmem: Require master to have ID zero, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 03/40] ivshmem-server: Don't overload POSIX shmem and file name, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 19/40] ivshmem: Clean up MSI-X conditions,
Markus Armbruster <=
- [Qemu-devel] [PULL v2 32/40] ivshmem: Simplify memory regions for BAR 2 (shared memory), Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 37/40] ivshmem: Clean up after the previous commit, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 26/40] ivshmem: Propagate errors through ivshmem_recv_setup(), Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 40/40] contrib/ivshmem-server: Print "not for production" warning, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 36/40] ivshmem: Split ivshmem-plain, ivshmem-doorbell off ivshmem, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 21/40] ivshmem: Assert interrupts are set up once, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 33/40] ivshmem: Inline check_shm_size() into its only caller, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 28/40] ivshmem: Drop the hackish test for UNIX domain chardev, Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 30/40] ivshmem: Tighten check of property "size", Markus Armbruster, 2016/03/21
- [Qemu-devel] [PULL v2 09/40] ivshmem-test: Improve test cases /ivshmem/server-*, Markus Armbruster, 2016/03/21