> -----Original Message----- > From: Jason Wang [mailto:jasowang@xxxxxxxxxx] > Sent: Monday, February 2, 2015 17:41 PM > To: Dexuan Cui > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; driverdev- > devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; apw@xxxxxxxxxxxxx; KY > Srinivasan; vkuznets@xxxxxxxxxx; Haiyang Zhang > Subject: Re: [PATCH v2 2/3] hv: vmbus_post_msg: retry the hypercall on some > transient errors > > On Mon, Feb 2, 2015 at 12:36 PM, Dexuan Cui <decui@xxxxxxxxxxxxx> wrote: > > I got HV_STATUS_INVALID_CONNECTION_ID on Hyper-V 2008 R2 when > keeping > > running > > "rmmod hv_netvsc; modprobe hv_netvsc; rmmod hv_utils; modprobe > > hv_utils" > > in a Linux guest. Looks the host has some kind of throttling > > mechanism if > > some kinds of hypercalls are sent too frequently. > > Better to clarify this kind of throttling. Looks like it only affects > HVCALL_POST_MESSAGE. Other looks good. I'm not sure about the details either. And it may be pretty host-specific, e.g., I can only get the error code on Hyper-V 2008 R2, but can't get it on 2012 R2. > Reviewed-by: Jason Wang <jasowang@xxxxxxxxxx> Thanks! > > > > Without the patch, the driver can occasionally fail to load. > > > > Also let's retry HV_STATUS_INSUFFICIENT_MEMORY, though we didn't get > > it > > before. > > > > Removed 'case -ENOMEM', since the hypervisor doesn't return this. > > > > CC: "K. Y. Srinivasan" <kys@xxxxxxxxxxxxx> > > Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> > > --- > > > > v2: > > updated the subject and changelog > > on HV_STATUS_INVALID_CONNECTION_ID: ret = -EAGAIN; > > added HV_STATUS_INSUFFICIENT_MEMORY > > removed unreachable -ENOMEM > > changed the delay from 100ms to 1000ms > > > > arch/x86/include/uapi/asm/hyperv.h | 2 ++ > > drivers/hv/connection.c | 11 +++++++++-- > > 2 files changed, 11 insertions(+), 2 deletions(-) > > > > diff --git a/arch/x86/include/uapi/asm/hyperv.h > > b/arch/x86/include/uapi/asm/hyperv.h > > index 90c458e..ce6068d 100644 > > --- a/arch/x86/include/uapi/asm/hyperv.h > > +++ b/arch/x86/include/uapi/asm/hyperv.h > > @@ -225,6 +225,8 @@ > > #define HV_STATUS_INVALID_HYPERCALL_CODE 2 > > #define HV_STATUS_INVALID_HYPERCALL_INPUT 3 > > #define HV_STATUS_INVALID_ALIGNMENT 4 > > +#define HV_STATUS_INSUFFICIENT_MEMORY 11 > > +#define HV_STATUS_INVALID_CONNECTION_ID 18 > > #define HV_STATUS_INSUFFICIENT_BUFFERS 19 > > > > typedef struct _HV_REFERENCE_TSC_PAGE { > > diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c > > index c4acd1c..af2388f 100644 > > --- a/drivers/hv/connection.c > > +++ b/drivers/hv/connection.c > > @@ -440,9 +440,16 @@ int vmbus_post_msg(void *buffer, size_t buflen) > > ret = hv_post_message(conn_id, 1, buffer, buflen); > > > > switch (ret) { > > + case HV_STATUS_INVALID_CONNECTION_ID: > > + /* > > + * We could get this if we send messages too > > + * frequently. > > + */ > > + ret = -EAGAIN; > > + break; > > + case HV_STATUS_INSUFFICIENT_MEMORY: > > case HV_STATUS_INSUFFICIENT_BUFFERS: > > ret = -ENOMEM; > > - case -ENOMEM: > > break; > > case HV_STATUS_SUCCESS: > > return ret; > > @@ -452,7 +459,7 @@ int vmbus_post_msg(void *buffer, size_t buflen) > > } > > > > retries++; > > - msleep(100); > > + msleep(1000); > > } > > return ret; > > } > > -- > > 1.9.1 > > _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
