From: Philipp Reisner Date: Fri, 30 Apr 2010 13:26:20 +0000 (+0200) Subject: drbd: Receiving of delay_probes X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0ced55a3bed25b0e30dcb3c7dce9634ce3c60cf2;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git drbd: Receiving of delay_probes Delay_probes are new packets in the DRBD protocol, which allow DRBD to know the current delay packets have on the data socket. (relative to the meta data socket) Signed-off-by: Philipp Reisner Signed-off-by: Lars Ellenberg --- diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 2409de12f013..fd7615f1e526 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -209,8 +209,11 @@ enum drbd_packets { P_RS_IS_IN_SYNC = 0x22, /* meta socket */ P_SYNC_PARAM89 = 0x23, /* data socket, protocol version 89 replacement for P_SYNC_PARAM */ P_COMPRESSED_BITMAP = 0x24, /* compressed or otherwise encoded bitmap transfer */ + /* P_CKPT_FENCE_REQ = 0x25, * currently reserved for protocol D */ + /* P_CKPT_DISABLE_REQ = 0x26, * currently reserved for protocol D */ + P_DELAY_PROBE = 0x27, /* is used on BOTH sockets */ - P_MAX_CMD = 0x25, + P_MAX_CMD = 0x28, P_MAY_IGNORE = 0x100, /* Flag to test if (cmd > P_MAY_IGNORE) ... */ P_MAX_OPT_CMD = 0x101, @@ -540,6 +543,18 @@ struct p_compressed_bm { u8 code[0]; } __packed; +struct p_delay_probe { + struct p_header head; + u32 seq_num; /* sequence number to match the two probe packets */ + u32 offset; /* usecs the probe got sent after the reference time point */ +} __packed; + +struct delay_probe { + struct list_head list; + int seq_num; + struct timeval time; +}; + /* DCBP: Drbd Compressed Bitmap Packet ... */ static inline enum drbd_bitmap_code DCBP_get_code(struct p_compressed_bm *p) @@ -1028,6 +1043,9 @@ struct drbd_conf { u64 ed_uuid; /* UUID of the exposed data */ struct mutex state_mutex; char congestion_reason; /* Why we where congested... */ + struct list_head delay_probes; /* protected by peer_seq_lock */ + int data_delay; /* Delay of packets on the data-sock behind meta-sock */ + atomic_t delay_seq; /* To generate sequence numbers of delay probes */ }; static inline struct drbd_conf *minor_to_mdev(unsigned int minor) diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 7468d2ce7347..3d5fe307a19d 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2608,6 +2608,7 @@ void drbd_init_set_defaults(struct drbd_conf *mdev) atomic_set(&mdev->net_cnt, 0); atomic_set(&mdev->packet_seq, 0); atomic_set(&mdev->pp_in_use, 0); + atomic_set(&mdev->delay_seq, 0); mutex_init(&mdev->md_io_mutex); mutex_init(&mdev->data.mutex); @@ -2636,6 +2637,8 @@ void drbd_init_set_defaults(struct drbd_conf *mdev) INIT_LIST_HEAD(&mdev->unplug_work.list); INIT_LIST_HEAD(&mdev->md_sync_work.list); INIT_LIST_HEAD(&mdev->bm_io_work.w.list); + INIT_LIST_HEAD(&mdev->delay_probes); + mdev->resync_work.cb = w_resync_inactive; mdev->unplug_work.cb = w_send_write_hint; mdev->md_sync_work.cb = w_md_sync; diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index b27f4dd36f89..fee0d249adf7 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -3501,6 +3501,92 @@ static int receive_UnplugRemote(struct drbd_conf *mdev, struct p_header *h) return TRUE; } +static void timeval_sub_us(struct timeval* tv, unsigned int us) +{ + tv->tv_sec -= us / 1000000; + us = us % 1000000; + if (tv->tv_usec > us) { + tv->tv_usec += 1000000; + tv->tv_sec--; + } + tv->tv_usec -= us; +} + +static void got_delay_probe(struct drbd_conf *mdev, int from, struct p_delay_probe *p) +{ + struct delay_probe *dp; + struct list_head *le; + struct timeval now; + int seq_num; + int offset; + int data_delay; + + seq_num = be32_to_cpu(p->seq_num); + offset = be32_to_cpu(p->offset); + + spin_lock(&mdev->peer_seq_lock); + if (!list_empty(&mdev->delay_probes)) { + if (from == USE_DATA_SOCKET) + le = mdev->delay_probes.next; + else + le = mdev->delay_probes.prev; + + dp = list_entry(le, struct delay_probe, list); + + if (dp->seq_num == seq_num) { + list_del(le); + spin_unlock(&mdev->peer_seq_lock); + do_gettimeofday(&now); + timeval_sub_us(&now, offset); + data_delay = + now.tv_usec - dp->time.tv_usec + + (now.tv_sec - dp->time.tv_sec) * 1000000; + + if (data_delay > 0) + mdev->data_delay = data_delay; + + kfree(dp); + return; + } + + if (dp->seq_num > seq_num) { + spin_unlock(&mdev->peer_seq_lock); + dev_warn(DEV, "Previous allocation failure of struct delay_probe?\n"); + return; /* Do not alloca a struct delay_probe.... */ + } + } + spin_unlock(&mdev->peer_seq_lock); + + dp = kmalloc(sizeof(struct delay_probe), GFP_NOIO); + if (!dp) { + dev_warn(DEV, "Failed to allocate a struct delay_probe, do not worry.\n"); + return; + } + + dp->seq_num = seq_num; + do_gettimeofday(&dp->time); + timeval_sub_us(&dp->time, offset); + + spin_lock(&mdev->peer_seq_lock); + if (from == USE_DATA_SOCKET) + list_add(&dp->list, &mdev->delay_probes); + else + list_add_tail(&dp->list, &mdev->delay_probes); + spin_unlock(&mdev->peer_seq_lock); +} + +static int receive_delay_probe(struct drbd_conf *mdev, struct p_header *h) +{ + struct p_delay_probe *p = (struct p_delay_probe *)h; + + ERR_IF(h->length != (sizeof(*p)-sizeof(*h))) return FALSE; + if (drbd_recv(mdev, h->payload, h->length) != h->length) + return FALSE; + + got_delay_probe(mdev, USE_DATA_SOCKET, p); + return TRUE; +} + typedef int (*drbd_cmd_handler_f)(struct drbd_conf *, struct p_header *); static drbd_cmd_handler_f drbd_default_handler[] = { @@ -3524,6 +3610,7 @@ static drbd_cmd_handler_f drbd_default_handler[] = { [P_OV_REQUEST] = receive_DataRequest, [P_OV_REPLY] = receive_DataRequest, [P_CSUM_RS_REQUEST] = receive_DataRequest, + [P_DELAY_PROBE] = receive_delay_probe, /* anything missing from this table is in * the asender_tbl, see get_asender_cmd */ [P_MAX_CMD] = NULL, @@ -4300,6 +4387,14 @@ static int got_OVResult(struct drbd_conf *mdev, struct p_header *h) return TRUE; } +static int got_delay_probe_m(struct drbd_conf *mdev, struct p_header *h) +{ + struct p_delay_probe *p = (struct p_delay_probe *)h; + + got_delay_probe(mdev, USE_META_SOCKET, p); + return TRUE; +} + struct asender_cmd { size_t pkt_size; int (*process)(struct drbd_conf *mdev, struct p_header *h); @@ -4324,6 +4419,7 @@ static struct asender_cmd *get_asender_cmd(int cmd) [P_BARRIER_ACK] = { sizeof(struct p_barrier_ack), got_BarrierAck }, [P_STATE_CHG_REPLY] = { sizeof(struct p_req_state_reply), got_RqSReply }, [P_RS_IS_IN_SYNC] = { sizeof(struct p_block_ack), got_IsInSync }, + [P_DELAY_PROBE] = { sizeof(struct p_delay_probe), got_delay_probe_m }, [P_MAX_CMD] = { 0, NULL }, }; if (cmd > P_MAX_CMD || asender_tbl[cmd].process == NULL)