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RDMA/ocrdma: Depend on async link events from CNA

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Recently Dough Ledford reported a deadlock happening
between ocrdma-load sequence and NetworkManager service
issuing "open" on be2net interface.

The deadlock happens when any be2net hook (e.g. open/close) is called
in parallel to insmod ocrdma.ko.

A. be2net is sending administrative open/close event to ocrdma holding
   device_list_mutex. It does this from ndo_open/ndo_stop hooks of be2net.
   So sequence of locks is rtnl_lock---> device_list lock

B.  When new ocrdma roce device gets registered, infiniband stack now
    takes rtnl_lock in ib_register_device() in GID initialization routines.
    So sequence of locks in this path is device_list lock ---> rtnl_lock.

This improper locking sequence causes deadlock.

With this patch we stop using administrative open and close events
injected by be2net driver. These events were used to dispatch PORT_ACTIVE
and PORT_ERROR events to the IB-stack. This patch implements a logic
to receive async-link-events generated from CNA whenever link-state-change
is detected. Now on, these async-events will be used to dispatch
PORT_ACTIVE and PORT_ERROR events to IB-stack.

Depending on async-events from CNA removes the need to hold device-list-mutex
and thus breaks the busy-wait scenario.

Reported-by: Doug Ledford <dledford@redhat.com>
CC: Sathya Perla <sathya.perla@avagotech.com>
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@avagotech.com>
Signed-off-by: Selvin Xavier <selvin.xavier@avagotech.com>
Signed-off-by: Devesh Sharma <devesh.sharma@avagotech.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
This commit is contained in:
Devesh Sharma 2015-12-24 13:14:07 -05:00 committed by Doug Ledford
parent d310a344e1
commit 3b1ea43009
6 changed files with 119 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/infiniband/hw/ocrdma/ocrdma.h
View File

@ -232,6 +232,10 @@ struct phy_info {
u16 interface_type;
};
enum ocrdma_flags {
OCRDMA_FLAGS_LINK_STATUS_INIT = 0x01
};
struct ocrdma_dev {
struct ib_device ibdev;
struct ocrdma_dev_attr attr;
@ -287,6 +291,7 @@ struct ocrdma_dev {
atomic_t update_sl;
u16 pvid;
u32 asic_id;
u32 flags;
ulong last_stats_time;
struct mutex stats_lock; /* provide synch for debugfs operations */
@ -591,4 +596,9 @@ static inline u8 ocrdma_is_enabled_and_synced(u32 state)
(state & OCRDMA_STATE_FLAG_SYNC);
}
static inline u8 ocrdma_get_ae_link_state(u32 ae_state)
{
return ((ae_state & OCRDMA_AE_LSC_LS_MASK) >> OCRDMA_AE_LSC_LS_SHIFT);
}
#endif

42
drivers/infiniband/hw/ocrdma/ocrdma_hw.c
View File

@ -579,6 +579,8 @@ static int ocrdma_mbx_create_mq(struct ocrdma_dev *dev,
cmd->async_event_bitmap = BIT(OCRDMA_ASYNC_GRP5_EVE_CODE);
cmd->async_event_bitmap |= BIT(OCRDMA_ASYNC_RDMA_EVE_CODE);
/* Request link events on this MQ. */
cmd->async_event_bitmap |= BIT(OCRDMA_ASYNC_LINK_EVE_CODE);
cmd->async_cqid_ringsize = cq->id;
cmd->async_cqid_ringsize |= (ocrdma_encoded_q_len(mq->len) <<
@ -819,20 +821,42 @@ static void ocrdma_process_grp5_aync(struct ocrdma_dev *dev,
}
}
static void ocrdma_process_link_state(struct ocrdma_dev *dev,
struct ocrdma_ae_mcqe *cqe)
{
struct ocrdma_ae_lnkst_mcqe *evt;
u8 lstate;
evt = (struct ocrdma_ae_lnkst_mcqe *)cqe;
lstate = ocrdma_get_ae_link_state(evt->speed_state_ptn);
if (!(lstate & OCRDMA_AE_LSC_LLINK_MASK))
return;
if (dev->flags & OCRDMA_FLAGS_LINK_STATUS_INIT)
ocrdma_update_link_state(dev, (lstate & OCRDMA_LINK_ST_MASK));
}
static void ocrdma_process_acqe(struct ocrdma_dev *dev, void *ae_cqe)
{
/* async CQE processing */
struct ocrdma_ae_mcqe *cqe = ae_cqe;
u32 evt_code = (cqe->valid_ae_event & OCRDMA_AE_MCQE_EVENT_CODE_MASK) >>
OCRDMA_AE_MCQE_EVENT_CODE_SHIFT;
if (evt_code == OCRDMA_ASYNC_RDMA_EVE_CODE)
switch (evt_code) {
case OCRDMA_ASYNC_LINK_EVE_CODE:
ocrdma_process_link_state(dev, cqe);
break;
case OCRDMA_ASYNC_RDMA_EVE_CODE:
ocrdma_dispatch_ibevent(dev, cqe);
else if (evt_code == OCRDMA_ASYNC_GRP5_EVE_CODE)
break;
case OCRDMA_ASYNC_GRP5_EVE_CODE:
ocrdma_process_grp5_aync(dev, cqe);
else
break;
default:
pr_err("%s(%d) invalid evt code=0x%x\n", __func__,
dev->id, evt_code);
}
}
static void ocrdma_process_mcqe(struct ocrdma_dev *dev, struct ocrdma_mcqe *cqe)
@ -1363,7 +1387,8 @@ mbx_err:
return status;
}
int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed)
int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed,
u8 *lnk_state)
{
int status = -ENOMEM;
struct ocrdma_get_link_speed_rsp *rsp;
@ -1384,8 +1409,11 @@ int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed)
goto mbx_err;
rsp = (struct ocrdma_get_link_speed_rsp *)cmd;
*lnk_speed = (rsp->pflt_pps_ld_pnum & OCRDMA_PHY_PS_MASK)
>> OCRDMA_PHY_PS_SHIFT;
if (lnk_speed)
*lnk_speed = (rsp->pflt_pps_ld_pnum & OCRDMA_PHY_PS_MASK)
>> OCRDMA_PHY_PS_SHIFT;
if (lnk_state)
*lnk_state = (rsp->res_lnk_st & OCRDMA_LINK_ST_MASK);
mbx_err:
kfree(cmd);

4
drivers/infiniband/hw/ocrdma/ocrdma_hw.h
View File

@ -106,7 +106,8 @@ void ocrdma_ring_cq_db(struct ocrdma_dev *, u16 cq_id, bool armed,
bool solicited, u16 cqe_popped);
/* verbs specific mailbox commands */
int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed);
int ocrdma_mbx_get_link_speed(struct ocrdma_dev *dev, u8 *lnk_speed,
u8 *lnk_st);
int ocrdma_query_config(struct ocrdma_dev *,
struct ocrdma_mbx_query_config *config);
@ -153,5 +154,6 @@ char *port_speed_string(struct ocrdma_dev *dev);
void ocrdma_init_service_level(struct ocrdma_dev *);
void ocrdma_alloc_pd_pool(struct ocrdma_dev *dev);
void ocrdma_free_pd_range(struct ocrdma_dev *dev);
void ocrdma_update_link_state(struct ocrdma_dev *dev, u8 lstate);
#endif /* __OCRDMA_HW_H__ */

34
drivers/infiniband/hw/ocrdma/ocrdma_main.c
View File

@ -289,6 +289,7 @@ static void ocrdma_remove_sysfiles(struct ocrdma_dev *dev)
static struct ocrdma_dev *ocrdma_add(struct be_dev_info *dev_info)
{
int status = 0, i;
u8 lstate = 0;
struct ocrdma_dev *dev;
dev = (struct ocrdma_dev *)ib_alloc_device(sizeof(struct ocrdma_dev));
@ -318,6 +319,11 @@ static struct ocrdma_dev *ocrdma_add(struct be_dev_info *dev_info)
if (status)
goto alloc_err;
/* Query Link state and update */
status = ocrdma_mbx_get_link_speed(dev, NULL, &lstate);
if (!status)
ocrdma_update_link_state(dev, lstate);
for (i = 0; i < ARRAY_SIZE(ocrdma_attributes); i++)
if (device_create_file(&dev->ibdev.dev, ocrdma_attributes[i]))
goto sysfs_err;
@ -372,7 +378,7 @@ static void ocrdma_remove(struct ocrdma_dev *dev)
ocrdma_remove_free(dev);
}
static int ocrdma_open(struct ocrdma_dev *dev)
static int ocrdma_dispatch_port_active(struct ocrdma_dev *dev)
{
struct ib_event port_event;
@ -383,7 +389,7 @@ static int ocrdma_open(struct ocrdma_dev *dev)
return 0;
}
static int ocrdma_close(struct ocrdma_dev *dev)
static int ocrdma_dispatch_port_error(struct ocrdma_dev *dev)
{
struct ib_event err_event;
@ -396,7 +402,7 @@ static int ocrdma_close(struct ocrdma_dev *dev)
static void ocrdma_shutdown(struct ocrdma_dev *dev)
{
ocrdma_close(dev);
ocrdma_dispatch_port_error(dev);
ocrdma_remove(dev);
}
@ -407,18 +413,28 @@ static void ocrdma_shutdown(struct ocrdma_dev *dev)
static void ocrdma_event_handler(struct ocrdma_dev *dev, u32 event)
{
switch (event) {
case BE_DEV_UP:
ocrdma_open(dev);
break;
case BE_DEV_DOWN:
ocrdma_close(dev);
break;
case BE_DEV_SHUTDOWN:
ocrdma_shutdown(dev);
break;
default:
break;
}
}
void ocrdma_update_link_state(struct ocrdma_dev *dev, u8 lstate)
{
if (!(dev->flags & OCRDMA_FLAGS_LINK_STATUS_INIT)) {
dev->flags |= OCRDMA_FLAGS_LINK_STATUS_INIT;
if (!lstate)
return;
}
if (!lstate)
ocrdma_dispatch_port_error(dev);
else
ocrdma_dispatch_port_active(dev);
}
static struct ocrdma_driver ocrdma_drv = {
.name = "ocrdma_driver",
.add = ocrdma_add,

49
drivers/infiniband/hw/ocrdma/ocrdma_sli.h
View File

@ -465,8 +465,11 @@ struct ocrdma_ae_qp_mcqe {
u32 valid_ae_event;
};
#define OCRDMA_ASYNC_RDMA_EVE_CODE 0x14
#define OCRDMA_ASYNC_GRP5_EVE_CODE 0x5
enum ocrdma_async_event_code {
OCRDMA_ASYNC_LINK_EVE_CODE = 0x01,
OCRDMA_ASYNC_GRP5_EVE_CODE = 0x05,
OCRDMA_ASYNC_RDMA_EVE_CODE = 0x14
};
enum ocrdma_async_grp5_events {
OCRDMA_ASYNC_EVENT_QOS_VALUE = 0x01,
@ -489,6 +492,44 @@ enum OCRDMA_ASYNC_EVENT_TYPE {
OCRDMA_MAX_ASYNC_ERRORS
};
struct ocrdma_ae_lnkst_mcqe {
u32 speed_state_ptn;
u32 qos_reason_falut;
u32 evt_tag;
u32 valid_ae_event;
};
enum {
OCRDMA_AE_LSC_PORT_NUM_MASK = 0x3F,
OCRDMA_AE_LSC_PT_SHIFT = 0x06,
OCRDMA_AE_LSC_PT_MASK = (0x03 <<
OCRDMA_AE_LSC_PT_SHIFT),
OCRDMA_AE_LSC_LS_SHIFT = 0x08,
OCRDMA_AE_LSC_LS_MASK = (0xFF <<
OCRDMA_AE_LSC_LS_SHIFT),
OCRDMA_AE_LSC_LD_SHIFT = 0x10,
OCRDMA_AE_LSC_LD_MASK = (0xFF <<
OCRDMA_AE_LSC_LD_SHIFT),
OCRDMA_AE_LSC_PPS_SHIFT = 0x18,
OCRDMA_AE_LSC_PPS_MASK = (0xFF <<
OCRDMA_AE_LSC_PPS_SHIFT),
OCRDMA_AE_LSC_PPF_MASK = 0xFF,
OCRDMA_AE_LSC_ER_SHIFT = 0x08,
OCRDMA_AE_LSC_ER_MASK = (0xFF <<
OCRDMA_AE_LSC_ER_SHIFT),
OCRDMA_AE_LSC_QOS_SHIFT = 0x10,
OCRDMA_AE_LSC_QOS_MASK = (0xFFFF <<
OCRDMA_AE_LSC_QOS_SHIFT)
};
enum {
OCRDMA_AE_LSC_PLINK_DOWN = 0x00,
OCRDMA_AE_LSC_PLINK_UP = 0x01,
OCRDMA_AE_LSC_LLINK_DOWN = 0x02,
OCRDMA_AE_LSC_LLINK_MASK = 0x02,
OCRDMA_AE_LSC_LLINK_UP = 0x03
};
/* mailbox command request and responses */
enum {
OCRDMA_MBX_QUERY_CFG_CQ_OVERFLOW_SHIFT = 2,
@ -676,7 +717,7 @@ enum {
OCRDMA_PHY_PFLT_SHIFT = 0x18,
OCRDMA_QOS_LNKSP_MASK = 0xFFFF0000,
OCRDMA_QOS_LNKSP_SHIFT = 0x10,
OCRDMA_LLST_MASK = 0xFF,
OCRDMA_LINK_ST_MASK = 0x01,
OCRDMA_PLFC_MASK = 0x00000400,
OCRDMA_PLFC_SHIFT = 0x8,
OCRDMA_PLRFC_MASK = 0x00000200,
@ -691,7 +732,7 @@ struct ocrdma_get_link_speed_rsp {
u32 pflt_pps_ld_pnum;
u32 qos_lsp;
u32 res_lls;
u32 res_lnk_st;
};
enum {

2
drivers/infiniband/hw/ocrdma/ocrdma_verbs.c
View File

@ -171,7 +171,7 @@ static inline void get_link_speed_and_width(struct ocrdma_dev *dev,
int status;
u8 speed;
status = ocrdma_mbx_get_link_speed(dev, &speed);
status = ocrdma_mbx_get_link_speed(dev, &speed, NULL);
if (status)
speed = OCRDMA_PHYS_LINK_SPEED_ZERO;