Commit a374c57b authored by Robin Holt's avatar Robin Holt Committed by Linus Torvalds

sgi-xpc: prevent false heartbeat failures

The heartbeat timeout functionality in sgi-xpc is currently not trained to
the connection time.  If a connection is made and the code is in the last
polling window prior to doing a timeout, the next polling window will see
the heartbeat as unchanged and initiate a no-heartbeat disconnect.
Signed-off-by: default avatarRobin Holt <holt@sgi.com>
Signed-off-by: default avatarDean Nelson <dcn@sgi.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a06bba46
......@@ -90,18 +90,21 @@ struct xpc_rsvd_page {
short max_npartitions; /* value of XPC_MAX_PARTITIONS */
u8 version;
u8 pad1[3]; /* align to next u64 in 1st 64-byte cacheline */
unsigned long ts_jiffies; /* timestamp when rsvd pg was setup by XPC */
union {
unsigned long vars_pa; /* phys address of struct xpc_vars */
unsigned long activate_gru_mq_desc_gpa; /* phys addr of */
/* activate mq's */
/* gru mq descriptor */
struct {
unsigned long vars_pa; /* phys addr */
} sn2;
struct {
unsigned long heartbeat_gpa; /* phys addr */
unsigned long activate_gru_mq_desc_gpa; /* phys addr */
} uv;
} sn;
unsigned long ts_jiffies; /* timestamp when rsvd pg was setup by XPC */
u64 pad2[10]; /* align to last u64 in 2nd 64-byte cacheline */
u64 pad2[9]; /* align to last u64 in 2nd 64-byte cacheline */
u64 SAL_nasids_size; /* SAL: size of each nasid mask in bytes */
};
#define XPC_RP_VERSION _XPC_VERSION(2, 0) /* version 2.0 of the reserved page */
#define XPC_RP_VERSION _XPC_VERSION(3, 0) /* version 3.0 of the reserved page */
/*
* Define the structures by which XPC variables can be exported to other
......@@ -182,6 +185,17 @@ struct xpc_vars_part_sn2 {
(XPC_RP_MACH_NASIDS(_rp) + \
xpc_nasid_mask_nlongs))
/*
* The following structure describes the partition's heartbeat info which
* will be periodically read by other partitions to determine whether this
* XPC is still 'alive'.
*/
struct xpc_heartbeat_uv {
unsigned long value;
unsigned long offline; /* if 0, heartbeat should be changing */
};
/*
* Info pertinent to a GRU message queue using a watch list for irq generation.
*/
......@@ -198,7 +212,7 @@ struct xpc_gru_mq_uv {
/*
* The activate_mq is used to send/receive GRU messages that affect XPC's
* heartbeat, partition active state, and channel state. This is UV only.
* partition active state and channel state. This is uv only.
*/
struct xpc_activate_mq_msghdr_uv {
unsigned int gru_msg_hdr; /* FOR GRU INTERNAL USE ONLY */
......@@ -210,33 +224,26 @@ struct xpc_activate_mq_msghdr_uv {
/* activate_mq defined message types */
#define XPC_ACTIVATE_MQ_MSG_SYNC_ACT_STATE_UV 0
#define XPC_ACTIVATE_MQ_MSG_INC_HEARTBEAT_UV 1
#define XPC_ACTIVATE_MQ_MSG_OFFLINE_HEARTBEAT_UV 2
#define XPC_ACTIVATE_MQ_MSG_ONLINE_HEARTBEAT_UV 3
#define XPC_ACTIVATE_MQ_MSG_ACTIVATE_REQ_UV 4
#define XPC_ACTIVATE_MQ_MSG_DEACTIVATE_REQ_UV 5
#define XPC_ACTIVATE_MQ_MSG_ACTIVATE_REQ_UV 1
#define XPC_ACTIVATE_MQ_MSG_DEACTIVATE_REQ_UV 2
#define XPC_ACTIVATE_MQ_MSG_CHCTL_CLOSEREQUEST_UV 6
#define XPC_ACTIVATE_MQ_MSG_CHCTL_CLOSEREPLY_UV 7
#define XPC_ACTIVATE_MQ_MSG_CHCTL_OPENREQUEST_UV 8
#define XPC_ACTIVATE_MQ_MSG_CHCTL_OPENREPLY_UV 9
#define XPC_ACTIVATE_MQ_MSG_CHCTL_CLOSEREQUEST_UV 3
#define XPC_ACTIVATE_MQ_MSG_CHCTL_CLOSEREPLY_UV 4
#define XPC_ACTIVATE_MQ_MSG_CHCTL_OPENREQUEST_UV 5
#define XPC_ACTIVATE_MQ_MSG_CHCTL_OPENREPLY_UV 6
#define XPC_ACTIVATE_MQ_MSG_MARK_ENGAGED_UV 10
#define XPC_ACTIVATE_MQ_MSG_MARK_DISENGAGED_UV 11
#define XPC_ACTIVATE_MQ_MSG_MARK_ENGAGED_UV 7
#define XPC_ACTIVATE_MQ_MSG_MARK_DISENGAGED_UV 8
struct xpc_activate_mq_msg_uv {
struct xpc_activate_mq_msghdr_uv hdr;
};
struct xpc_activate_mq_msg_heartbeat_req_uv {
struct xpc_activate_mq_msghdr_uv hdr;
u64 heartbeat;
};
struct xpc_activate_mq_msg_activate_req_uv {
struct xpc_activate_mq_msghdr_uv hdr;
unsigned long rp_gpa;
unsigned long heartbeat_gpa;
unsigned long activate_gru_mq_desc_gpa;
};
......@@ -687,6 +694,9 @@ struct xpc_partition_sn2 {
};
struct xpc_partition_uv {
unsigned long heartbeat_gpa; /* phys addr of partition's heartbeat */
struct xpc_heartbeat_uv cached_heartbeat; /* cached copy of */
/* partition's heartbeat */
unsigned long activate_gru_mq_desc_gpa; /* phys addr of parititon's */
/* activate mq's gru mq */
/* descriptor */
......@@ -698,14 +708,12 @@ struct xpc_partition_uv {
u8 remote_act_state; /* remote partition's act_state */
u8 act_state_req; /* act_state request from remote partition */
enum xp_retval reason; /* reason for deactivate act_state request */
u64 heartbeat; /* incremented by remote partition */
};
/* struct xpc_partition_uv flags */
#define XPC_P_HEARTBEAT_OFFLINE_UV 0x00000001
#define XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV 0x00000001
#define XPC_P_ENGAGED_UV 0x00000002
#define XPC_P_CACHED_ACTIVATE_GRU_MQ_DESC_UV 0x00000004
/* struct xpc_partition_uv act_state change requests */
......@@ -807,7 +815,6 @@ extern int xpc_disengage_timedout;
extern int xpc_activate_IRQ_rcvd;
extern spinlock_t xpc_activate_IRQ_rcvd_lock;
extern wait_queue_head_t xpc_activate_IRQ_wq;
extern void *xpc_heartbeating_to_mask;
extern void *xpc_kzalloc_cacheline_aligned(size_t, gfp_t, void **);
extern void xpc_activate_partition(struct xpc_partition *);
extern void xpc_activate_kthreads(struct xpc_channel *, int);
......@@ -825,6 +832,9 @@ extern void (*xpc_increment_heartbeat) (void);
extern void (*xpc_offline_heartbeat) (void);
extern void (*xpc_online_heartbeat) (void);
extern enum xp_retval (*xpc_get_remote_heartbeat) (struct xpc_partition *);
extern void (*xpc_allow_hb) (short);
extern void (*xpc_disallow_hb) (short);
extern void (*xpc_disallow_all_hbs) (void);
extern enum xp_retval (*xpc_make_first_contact) (struct xpc_partition *);
extern u64 (*xpc_get_chctl_all_flags) (struct xpc_partition *);
extern enum xp_retval (*xpc_setup_msg_structures) (struct xpc_channel *);
......@@ -909,40 +919,6 @@ extern void xpc_disconnect_channel(const int, struct xpc_channel *,
extern void xpc_disconnect_callout(struct xpc_channel *, enum xp_retval);
extern void xpc_partition_going_down(struct xpc_partition *, enum xp_retval);
static inline int
xpc_hb_allowed(short partid, void *heartbeating_to_mask)
{
return test_bit(partid, heartbeating_to_mask);
}
static inline int
xpc_any_hbs_allowed(void)
{
DBUG_ON(xpc_heartbeating_to_mask == NULL);
return !bitmap_empty(xpc_heartbeating_to_mask, xp_max_npartitions);
}
static inline void
xpc_allow_hb(short partid)
{
DBUG_ON(xpc_heartbeating_to_mask == NULL);
set_bit(partid, xpc_heartbeating_to_mask);
}
static inline void
xpc_disallow_hb(short partid)
{
DBUG_ON(xpc_heartbeating_to_mask == NULL);
clear_bit(partid, xpc_heartbeating_to_mask);
}
static inline void
xpc_disallow_all_hbs(void)
{
DBUG_ON(xpc_heartbeating_to_mask == NULL);
bitmap_zero(xpc_heartbeating_to_mask, xp_max_npartitions);
}
static inline void
xpc_wakeup_channel_mgr(struct xpc_partition *part)
{
......
......@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2004-2008 Silicon Graphics, Inc. All Rights Reserved.
* Copyright (c) 2004-2009 Silicon Graphics, Inc. All Rights Reserved.
*/
/*
......@@ -150,7 +150,6 @@ DECLARE_WAIT_QUEUE_HEAD(xpc_activate_IRQ_wq);
static unsigned long xpc_hb_check_timeout;
static struct timer_list xpc_hb_timer;
void *xpc_heartbeating_to_mask;
/* notification that the xpc_hb_checker thread has exited */
static DECLARE_COMPLETION(xpc_hb_checker_exited);
......@@ -176,6 +175,10 @@ enum xp_retval (*xpc_get_partition_rsvd_page_pa) (void *buf, u64 *cookie,
unsigned long *rp_pa,
size_t *len);
int (*xpc_setup_rsvd_page_sn) (struct xpc_rsvd_page *rp);
void (*xpc_allow_hb) (short partid);
void (*xpc_disallow_hb) (short partid);
void (*xpc_disallow_all_hbs) (void);
void (*xpc_heartbeat_init) (void);
void (*xpc_heartbeat_exit) (void);
void (*xpc_increment_heartbeat) (void);
......@@ -1087,7 +1090,6 @@ xpc_do_exit(enum xp_retval reason)
} while (1);
DBUG_ON(xpc_any_partition_engaged());
DBUG_ON(xpc_any_hbs_allowed() != 0);
xpc_teardown_rsvd_page();
......
......@@ -3,7 +3,7 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (c) 2008 Silicon Graphics, Inc. All Rights Reserved.
* Copyright (c) 2008-2009 Silicon Graphics, Inc. All Rights Reserved.
*/
/*
......@@ -629,7 +629,7 @@ xpc_setup_rsvd_page_sn_sn2(struct xpc_rsvd_page *rp)
xpc_vars_sn2 = XPC_RP_VARS(rp);
rp->sn.vars_pa = xp_pa(xpc_vars_sn2);
rp->sn.sn2.vars_pa = xp_pa(xpc_vars_sn2);
/* vars_part array follows immediately after vars */
xpc_vars_part_sn2 = (struct xpc_vars_part_sn2 *)((u8 *)XPC_RP_VARS(rp) +
......@@ -693,6 +693,33 @@ xpc_setup_rsvd_page_sn_sn2(struct xpc_rsvd_page *rp)
return 0;
}
static int
xpc_hb_allowed_sn2(short partid, void *heartbeating_to_mask)
{
return test_bit(partid, heartbeating_to_mask);
}
static void
xpc_allow_hb_sn2(short partid)
{
DBUG_ON(xpc_vars_sn2 == NULL);
set_bit(partid, xpc_vars_sn2->heartbeating_to_mask);
}
static void
xpc_disallow_hb_sn2(short partid)
{
DBUG_ON(xpc_vars_sn2 == NULL);
clear_bit(partid, xpc_vars_sn2->heartbeating_to_mask);
}
static void
xpc_disallow_all_hbs_sn2(void)
{
DBUG_ON(xpc_vars_sn2 == NULL);
bitmap_zero(xpc_vars_sn2->heartbeating_to_mask, xp_max_npartitions);
}
static void
xpc_increment_heartbeat_sn2(void)
{
......@@ -719,7 +746,6 @@ xpc_heartbeat_init_sn2(void)
DBUG_ON(xpc_vars_sn2 == NULL);
bitmap_zero(xpc_vars_sn2->heartbeating_to_mask, XP_MAX_NPARTITIONS_SN2);
xpc_heartbeating_to_mask = &xpc_vars_sn2->heartbeating_to_mask[0];
xpc_online_heartbeat_sn2();
}
......@@ -751,9 +777,9 @@ xpc_get_remote_heartbeat_sn2(struct xpc_partition *part)
remote_vars->heartbeating_to_mask[0]);
if ((remote_vars->heartbeat == part->last_heartbeat &&
remote_vars->heartbeat_offline == 0) ||
!xpc_hb_allowed(sn_partition_id,
&remote_vars->heartbeating_to_mask)) {
!remote_vars->heartbeat_offline) ||
!xpc_hb_allowed_sn2(sn_partition_id,
remote_vars->heartbeating_to_mask)) {
ret = xpNoHeartbeat;
} else {
part->last_heartbeat = remote_vars->heartbeat;
......@@ -972,7 +998,7 @@ xpc_identify_activate_IRQ_req_sn2(int nasid)
return;
}
remote_vars_pa = remote_rp->sn.vars_pa;
remote_vars_pa = remote_rp->sn.sn2.vars_pa;
remote_rp_version = remote_rp->version;
remote_rp_ts_jiffies = remote_rp->ts_jiffies;
......@@ -2325,6 +2351,10 @@ xpc_init_sn2(void)
xpc_teardown_partitions_sn = xpc_teardown_partitions_sn_sn2;
xpc_get_partition_rsvd_page_pa = xpc_get_partition_rsvd_page_pa_sn2;
xpc_setup_rsvd_page_sn = xpc_setup_rsvd_page_sn_sn2;
xpc_allow_hb = xpc_allow_hb_sn2;
xpc_disallow_hb = xpc_disallow_hb_sn2;
xpc_disallow_all_hbs = xpc_disallow_all_hbs_sn2;
xpc_increment_heartbeat = xpc_increment_heartbeat_sn2;
xpc_offline_heartbeat = xpc_offline_heartbeat_sn2;
xpc_online_heartbeat = xpc_online_heartbeat_sn2;
......
......@@ -46,8 +46,7 @@ struct uv_IO_APIC_route_entry {
};
#endif
static atomic64_t xpc_heartbeat_uv;
static DECLARE_BITMAP(xpc_heartbeating_to_mask_uv, XP_MAX_NPARTITIONS_UV);
static struct xpc_heartbeat_uv *xpc_heartbeat_uv;
#define XPC_ACTIVATE_MSG_SIZE_UV (1 * GRU_CACHE_LINE_BYTES)
#define XPC_ACTIVATE_MQ_SIZE_UV (4 * XP_MAX_NPARTITIONS_UV * \
......@@ -423,41 +422,6 @@ xpc_handle_activate_mq_msg_uv(struct xpc_partition *part,
/* syncing of remote_act_state was just done above */
break;
case XPC_ACTIVATE_MQ_MSG_INC_HEARTBEAT_UV: {
struct xpc_activate_mq_msg_heartbeat_req_uv *msg;
msg = container_of(msg_hdr,
struct xpc_activate_mq_msg_heartbeat_req_uv,
hdr);
part_uv->heartbeat = msg->heartbeat;
break;
}
case XPC_ACTIVATE_MQ_MSG_OFFLINE_HEARTBEAT_UV: {
struct xpc_activate_mq_msg_heartbeat_req_uv *msg;
msg = container_of(msg_hdr,
struct xpc_activate_mq_msg_heartbeat_req_uv,
hdr);
part_uv->heartbeat = msg->heartbeat;
spin_lock_irqsave(&part_uv->flags_lock, irq_flags);
part_uv->flags |= XPC_P_HEARTBEAT_OFFLINE_UV;
spin_unlock_irqrestore(&part_uv->flags_lock, irq_flags);
break;
}
case XPC_ACTIVATE_MQ_MSG_ONLINE_HEARTBEAT_UV: {
struct xpc_activate_mq_msg_heartbeat_req_uv *msg;
msg = container_of(msg_hdr,
struct xpc_activate_mq_msg_heartbeat_req_uv,
hdr);
part_uv->heartbeat = msg->heartbeat;
spin_lock_irqsave(&part_uv->flags_lock, irq_flags);
part_uv->flags &= ~XPC_P_HEARTBEAT_OFFLINE_UV;
spin_unlock_irqrestore(&part_uv->flags_lock, irq_flags);
break;
}
case XPC_ACTIVATE_MQ_MSG_ACTIVATE_REQ_UV: {
struct xpc_activate_mq_msg_activate_req_uv *msg;
......@@ -475,6 +439,7 @@ xpc_handle_activate_mq_msg_uv(struct xpc_partition *part,
part_uv->act_state_req = XPC_P_ASR_ACTIVATE_UV;
part->remote_rp_pa = msg->rp_gpa; /* !!! _pa is _gpa */
part->remote_rp_ts_jiffies = msg_hdr->rp_ts_jiffies;
part_uv->heartbeat_gpa = msg->heartbeat_gpa;
if (msg->activate_gru_mq_desc_gpa !=
part_uv->activate_gru_mq_desc_gpa) {
......@@ -759,7 +724,7 @@ xpc_send_local_activate_IRQ_uv(struct xpc_partition *part, int act_state_req)
/*
* !!! Make our side think that the remote partition sent an activate
* !!! message our way by doing what the activate IRQ handler would
* !!! mq message our way by doing what the activate IRQ handler would
* !!! do had one really been sent.
*/
......@@ -808,88 +773,80 @@ xpc_get_partition_rsvd_page_pa_uv(void *buf, u64 *cookie, unsigned long *rp_pa,
static int
xpc_setup_rsvd_page_sn_uv(struct xpc_rsvd_page *rp)
{
rp->sn.activate_gru_mq_desc_gpa =
xpc_heartbeat_uv =
&xpc_partitions[sn_partition_id].sn.uv.cached_heartbeat;
rp->sn.uv.heartbeat_gpa = uv_gpa(xpc_heartbeat_uv);
rp->sn.uv.activate_gru_mq_desc_gpa =
uv_gpa(xpc_activate_mq_uv->gru_mq_desc);
return 0;
}
static void
xpc_send_heartbeat_uv(int msg_type)
xpc_allow_hb_uv(short partid)
{
short partid;
struct xpc_partition *part;
struct xpc_activate_mq_msg_heartbeat_req_uv msg;
/*
* !!! On uv we're broadcasting a heartbeat message every 5 seconds.
* !!! Whereas on sn2 we're bte_copy'ng the heartbeat info every 20
* !!! seconds. This is an increase in numalink traffic.
* ??? Is this good?
*/
msg.heartbeat = atomic64_inc_return(&xpc_heartbeat_uv);
partid = find_first_bit(xpc_heartbeating_to_mask_uv,
XP_MAX_NPARTITIONS_UV);
while (partid < XP_MAX_NPARTITIONS_UV) {
part = &xpc_partitions[partid];
}
xpc_send_activate_IRQ_part_uv(part, &msg, sizeof(msg),
msg_type);
static void
xpc_disallow_hb_uv(short partid)
{
}
partid = find_next_bit(xpc_heartbeating_to_mask_uv,
XP_MAX_NPARTITIONS_UV, partid + 1);
}
static void
xpc_disallow_all_hbs_uv(void)
{
}
static void
xpc_increment_heartbeat_uv(void)
{
xpc_send_heartbeat_uv(XPC_ACTIVATE_MQ_MSG_INC_HEARTBEAT_UV);
xpc_heartbeat_uv->value++;
}
static void
xpc_offline_heartbeat_uv(void)
{
xpc_send_heartbeat_uv(XPC_ACTIVATE_MQ_MSG_OFFLINE_HEARTBEAT_UV);
xpc_increment_heartbeat_uv();
xpc_heartbeat_uv->offline = 1;
}
static void
xpc_online_heartbeat_uv(void)
{
xpc_send_heartbeat_uv(XPC_ACTIVATE_MQ_MSG_ONLINE_HEARTBEAT_UV);
xpc_increment_heartbeat_uv();
xpc_heartbeat_uv->offline = 0;
}
static void
xpc_heartbeat_init_uv(void)
{
atomic64_set(&xpc_heartbeat_uv, 0);
bitmap_zero(xpc_heartbeating_to_mask_uv, XP_MAX_NPARTITIONS_UV);
xpc_heartbeating_to_mask = &xpc_heartbeating_to_mask_uv[0];
xpc_heartbeat_uv->value = 1;
xpc_heartbeat_uv->offline = 0;
}
static void
xpc_heartbeat_exit_uv(void)
{
xpc_send_heartbeat_uv(XPC_ACTIVATE_MQ_MSG_OFFLINE_HEARTBEAT_UV);
xpc_offline_heartbeat_uv();
}
static enum xp_retval
xpc_get_remote_heartbeat_uv(struct xpc_partition *part)
{
struct xpc_partition_uv *part_uv = &part->sn.uv;
enum xp_retval ret = xpNoHeartbeat;
enum xp_retval ret;
if (part_uv->remote_act_state != XPC_P_AS_INACTIVE &&
part_uv->remote_act_state != XPC_P_AS_DEACTIVATING) {
ret = xp_remote_memcpy(uv_gpa(&part_uv->cached_heartbeat),
part_uv->heartbeat_gpa,
sizeof(struct xpc_heartbeat_uv));
if (ret != xpSuccess)
return ret;
if (part_uv->heartbeat != part->last_heartbeat ||
(part_uv->flags & XPC_P_HEARTBEAT_OFFLINE_UV)) {
if (part_uv->cached_heartbeat.value == part->last_heartbeat &&
!part_uv->cached_heartbeat.offline) {
part->last_heartbeat = part_uv->heartbeat;
ret = xpSuccess;
}
ret = xpNoHeartbeat;
} else {
part->last_heartbeat = part_uv->cached_heartbeat.value;
}
return ret;
}
......@@ -904,8 +861,9 @@ xpc_request_partition_activation_uv(struct xpc_rsvd_page *remote_rp,
part->remote_rp_pa = remote_rp_gpa; /* !!! _pa here is really _gpa */
part->remote_rp_ts_jiffies = remote_rp->ts_jiffies;
part->sn.uv.heartbeat_gpa = remote_rp->sn.uv.heartbeat_gpa;
part->sn.uv.activate_gru_mq_desc_gpa =
remote_rp->sn.activate_gru_mq_desc_gpa;
remote_rp->sn.uv.activate_gru_mq_desc_gpa;
/*
* ??? Is it a good idea to make this conditional on what is
......@@ -913,8 +871,9 @@ xpc_request_partition_activation_uv(struct xpc_rsvd_page *remote_rp,
*/
if (part->sn.uv.remote_act_state == XPC_P_AS_INACTIVE) {
msg.rp_gpa = uv_gpa(xpc_rsvd_page);
msg.heartbeat_gpa = xpc_rsvd_page->sn.uv.heartbeat_gpa;
msg.activate_gru_mq_desc_gpa =
xpc_rsvd_page->sn.activate_gru_mq_desc_gpa;
xpc_rsvd_page->sn.uv.activate_gru_mq_desc_gpa;
xpc_send_activate_IRQ_part_uv(part, &msg, sizeof(msg),
XPC_ACTIVATE_MQ_MSG_ACTIVATE_REQ_UV);
}
......@@ -1677,6 +1636,10 @@ xpc_init_uv(void)
xpc_process_activate_IRQ_rcvd = xpc_process_activate_IRQ_rcvd_uv;
xpc_get_partition_rsvd_page_pa = xpc_get_partition_rsvd_page_pa_uv;
xpc_setup_rsvd_page_sn = xpc_setup_rsvd_page_sn_uv;
xpc_allow_hb = xpc_allow_hb_uv;
xpc_disallow_hb = xpc_disallow_hb_uv;
xpc_disallow_all_hbs = xpc_disallow_all_hbs_uv;
xpc_increment_heartbeat = xpc_increment_heartbeat_uv;
xpc_offline_heartbeat = xpc_offline_heartbeat_uv;
xpc_online_heartbeat = xpc_online_heartbeat_uv;
......
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