The function hv_post_msg() can fail because of transient resource conditions. It may be useful to retry the operation.
Signed-off-by: K. Y. Srinivasan <[email protected]> Signed-off-by: Haiyang Zhang <[email protected]> Signed-off-by: Hank Janssen <[email protected]> --- arch/x86/include/asm/hyperv.h | 1 + drivers/staging/hv/connection.c | 18 +++++++++++++++++- 2 files changed, 18 insertions(+), 1 deletions(-) diff --git a/arch/x86/include/asm/hyperv.h b/arch/x86/include/asm/hyperv.h index 5df477a..b80420b 100644 --- a/arch/x86/include/asm/hyperv.h +++ b/arch/x86/include/asm/hyperv.h @@ -189,5 +189,6 @@ #define HV_STATUS_INVALID_HYPERCALL_CODE 2 #define HV_STATUS_INVALID_HYPERCALL_INPUT 3 #define HV_STATUS_INVALID_ALIGNMENT 4 +#define HV_STATUS_INSUFFICIENT_BUFFERS 19 #endif diff --git a/drivers/staging/hv/connection.c b/drivers/staging/hv/connection.c index 0e7efce..a88ad70 100644 --- a/drivers/staging/hv/connection.c +++ b/drivers/staging/hv/connection.c @@ -25,6 +25,7 @@ #include <linux/kernel.h> #include <linux/sched.h> #include <linux/wait.h> +#include <linux/delay.h> #include <linux/mm.h> #include <linux/slab.h> #include <linux/vmalloc.h> @@ -268,10 +269,25 @@ void vmbus_on_event(unsigned long data) int vmbus_post_msg(void *buffer, size_t buflen) { union hv_connection_id conn_id; + int ret = 0; + int retries = 0; conn_id.asu32 = 0; conn_id.u.id = VMBUS_MESSAGE_CONNECTION_ID; - return hv_post_message(conn_id, 1, buffer, buflen); + + /* + * hv_post_message() can have transient failures because of + * insufficient resources. Retry the operation a couple of + * times before giving up. + */ + while (retries < 3) { + ret = hv_post_message(conn_id, 1, buffer, buflen); + if (ret != HV_STATUS_INSUFFICIENT_BUFFERS) + return ret; + retries++; + msleep(100); + } + return ret; } /* -- 1.7.4.1 _______________________________________________ devel mailing list [email protected] http://driverdev.linuxdriverproject.org/mailman/listinfo/devel
