[04/29] Staging: hv: fix smp problems in the hyperv core code

From: Greg KH
Date: Fri Jan 22 2010 - 19:29:38 EST


2.6.32-stable review patch. If anyone has any objections, please let us know.

------------------

From: Greg Kroah-Hartman <gregkh@xxxxxxx>

commit 7692fd4d441afac728cb83fdd33349d5ba07406c upstream.

This fixes a number of SMP problems that were in the hyperv core code.

Patch originally written by K. Y. Srinivasan <ksrinivasan@xxxxxxxxxx>
but forward ported to the latest in-kernel code and tweaked slightly by
me.

Novell, Inc. hereby disclaims all copyright in any derivative work
copyright associated with this patch.

Signed-off-by: K. Y. Srinivasan <ksrinivasan@xxxxxxxxxx>
Cc: Hank Janssen <hjanssen@xxxxxxxxxxxxx>
Cc: Haiyang Zhang <haiyangz@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/staging/hv/Hv.c | 50 ++++++++++++++++++++++-----------------------
drivers/staging/hv/Hv.h | 6 ++---
drivers/staging/hv/Vmbus.c | 12 ++++++----
3 files changed, 35 insertions(+), 33 deletions(-)

--- a/drivers/staging/hv/Hv.c
+++ b/drivers/staging/hv/Hv.c
@@ -386,7 +386,7 @@ u16 HvSignalEvent(void)
* retrieve the initialized message and event pages. Otherwise, we create and
* initialize the message and event pages.
*/
-int HvSynicInit(u32 irqVector)
+void HvSynicInit(void *irqarg)
{
u64 version;
union hv_synic_simp simp;
@@ -394,13 +394,14 @@ int HvSynicInit(u32 irqVector)
union hv_synic_sint sharedSint;
union hv_synic_scontrol sctrl;
u64 guestID;
- int ret = 0;
+ u32 irqVector = *((u32 *)(irqarg));
+ int cpu = smp_processor_id();

DPRINT_ENTER(VMBUS);

if (!gHvContext.HypercallPage) {
DPRINT_EXIT(VMBUS);
- return ret;
+ return;
}

/* Check the version */
@@ -425,27 +426,27 @@ int HvSynicInit(u32 irqVector)
*/
rdmsrl(HV_X64_MSR_GUEST_OS_ID, guestID);
if (guestID == HV_LINUX_GUEST_ID) {
- gHvContext.synICMessagePage[0] =
+ gHvContext.synICMessagePage[cpu] =
phys_to_virt(simp.BaseSimpGpa << PAGE_SHIFT);
- gHvContext.synICEventPage[0] =
+ gHvContext.synICEventPage[cpu] =
phys_to_virt(siefp.BaseSiefpGpa << PAGE_SHIFT);
} else {
DPRINT_ERR(VMBUS, "unknown guest id!!");
goto Cleanup;
}
DPRINT_DBG(VMBUS, "MAPPED: Simp: %p, Sifep: %p",
- gHvContext.synICMessagePage[0],
- gHvContext.synICEventPage[0]);
+ gHvContext.synICMessagePage[cpu],
+ gHvContext.synICEventPage[cpu]);
} else {
- gHvContext.synICMessagePage[0] = osd_PageAlloc(1);
- if (gHvContext.synICMessagePage[0] == NULL) {
+ gHvContext.synICMessagePage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
+ if (gHvContext.synICMessagePage[cpu] == NULL) {
DPRINT_ERR(VMBUS,
"unable to allocate SYNIC message page!!");
goto Cleanup;
}

- gHvContext.synICEventPage[0] = osd_PageAlloc(1);
- if (gHvContext.synICEventPage[0] == NULL) {
+ gHvContext.synICEventPage[cpu] = (void *)get_zeroed_page(GFP_ATOMIC);
+ if (gHvContext.synICEventPage[cpu] == NULL) {
DPRINT_ERR(VMBUS,
"unable to allocate SYNIC event page!!");
goto Cleanup;
@@ -454,7 +455,7 @@ int HvSynicInit(u32 irqVector)
/* Setup the Synic's message page */
rdmsrl(HV_X64_MSR_SIMP, simp.AsUINT64);
simp.SimpEnabled = 1;
- simp.BaseSimpGpa = virt_to_phys(gHvContext.synICMessagePage[0])
+ simp.BaseSimpGpa = virt_to_phys(gHvContext.synICMessagePage[cpu])
>> PAGE_SHIFT;

DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx",
@@ -465,7 +466,7 @@ int HvSynicInit(u32 irqVector)
/* Setup the Synic's event page */
rdmsrl(HV_X64_MSR_SIEFP, siefp.AsUINT64);
siefp.SiefpEnabled = 1;
- siefp.BaseSiefpGpa = virt_to_phys(gHvContext.synICEventPage[0])
+ siefp.BaseSiefpGpa = virt_to_phys(gHvContext.synICEventPage[cpu])
>> PAGE_SHIFT;

DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx",
@@ -501,32 +502,30 @@ int HvSynicInit(u32 irqVector)

DPRINT_EXIT(VMBUS);

- return ret;
+ return;

Cleanup:
- ret = -1;
-
if (gHvContext.GuestId == HV_LINUX_GUEST_ID) {
- if (gHvContext.synICEventPage[0])
- osd_PageFree(gHvContext.synICEventPage[0], 1);
+ if (gHvContext.synICEventPage[cpu])
+ osd_PageFree(gHvContext.synICEventPage[cpu], 1);

- if (gHvContext.synICMessagePage[0])
- osd_PageFree(gHvContext.synICMessagePage[0], 1);
+ if (gHvContext.synICMessagePage[cpu])
+ osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
}

DPRINT_EXIT(VMBUS);
-
- return ret;
+ return;
}

/**
* HvSynicCleanup - Cleanup routine for HvSynicInit().
*/
-void HvSynicCleanup(void)
+void HvSynicCleanup(void *arg)
{
union hv_synic_sint sharedSint;
union hv_synic_simp simp;
union hv_synic_siefp siefp;
+ int cpu = smp_processor_id();

DPRINT_ENTER(VMBUS);

@@ -539,6 +538,7 @@ void HvSynicCleanup(void)

sharedSint.Masked = 1;

+ /* Need to correctly cleanup in the case of SMP!!! */
/* Disable the interrupt */
wrmsrl(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.AsUINT64);

@@ -560,8 +560,8 @@ void HvSynicCleanup(void)

wrmsrl(HV_X64_MSR_SIEFP, siefp.AsUINT64);

- osd_PageFree(gHvContext.synICMessagePage[0], 1);
- osd_PageFree(gHvContext.synICEventPage[0], 1);
+ osd_PageFree(gHvContext.synICMessagePage[cpu], 1);
+ osd_PageFree(gHvContext.synICEventPage[cpu], 1);
}

DPRINT_EXIT(VMBUS);
--- a/drivers/staging/hv/Hv.h
+++ b/drivers/staging/hv/Hv.h
@@ -93,7 +93,7 @@ static const struct hv_guid VMBUS_SERVIC
},
};

-#define MAX_NUM_CPUS 1
+#define MAX_NUM_CPUS 32


struct hv_input_signal_event_buffer {
@@ -137,8 +137,8 @@ extern u16 HvPostMessage(union hv_connec

extern u16 HvSignalEvent(void);

-extern int HvSynicInit(u32 irqVector);
+extern void HvSynicInit(void *irqarg);

-extern void HvSynicCleanup(void);
+extern void HvSynicCleanup(void *arg);

#endif /* __HV_H__ */
--- a/drivers/staging/hv/Vmbus.c
+++ b/drivers/staging/hv/Vmbus.c
@@ -129,7 +129,7 @@ static int VmbusOnDeviceAdd(struct hv_de

/* strcpy(dev->name, "vmbus"); */
/* SynIC setup... */
- ret = HvSynicInit(*irqvector);
+ on_each_cpu(HvSynicInit, (void *)irqvector, 1);

/* Connect to VMBus in the root partition */
ret = VmbusConnect();
@@ -150,7 +150,7 @@ static int VmbusOnDeviceRemove(struct hv
DPRINT_ENTER(VMBUS);
VmbusChannelReleaseUnattachedChannels();
VmbusDisconnect();
- HvSynicCleanup();
+ on_each_cpu(HvSynicCleanup, NULL, 1);
DPRINT_EXIT(VMBUS);

return ret;
@@ -173,7 +173,8 @@ static void VmbusOnCleanup(struct hv_dri
*/
static void VmbusOnMsgDPC(struct hv_driver *drv)
{
- void *page_addr = gHvContext.synICMessagePage[0];
+ int cpu = smp_processor_id();
+ void *page_addr = gHvContext.synICMessagePage[cpu];
struct hv_message *msg = (struct hv_message *)page_addr +
VMBUS_MESSAGE_SINT;
struct hv_message *copied;
@@ -230,11 +231,12 @@ static void VmbusOnEventDPC(struct hv_dr
static int VmbusOnISR(struct hv_driver *drv)
{
int ret = 0;
+ int cpu = smp_processor_id();
void *page_addr;
struct hv_message *msg;
union hv_synic_event_flags *event;

- page_addr = gHvContext.synICMessagePage[0];
+ page_addr = gHvContext.synICMessagePage[cpu];
msg = (struct hv_message *)page_addr + VMBUS_MESSAGE_SINT;

DPRINT_ENTER(VMBUS);
@@ -248,7 +250,7 @@ static int VmbusOnISR(struct hv_driver *
}

/* TODO: Check if there are events to be process */
- page_addr = gHvContext.synICEventPage[0];
+ page_addr = gHvContext.synICEventPage[cpu];
event = (union hv_synic_event_flags *)page_addr + VMBUS_MESSAGE_SINT;

/* Since we are a child, we only need to check bit 0 */


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