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-rw-r--r--src/kernel/dnbd3.h34
-rw-r--r--src/kernel/mq.c34
-rw-r--r--src/kernel/mq.h4
-rw-r--r--src/kernel/net.c123
4 files changed, 99 insertions, 96 deletions
diff --git a/src/kernel/dnbd3.h b/src/kernel/dnbd3.h
index 4a2302d..01e8c15 100644
--- a/src/kernel/dnbd3.h
+++ b/src/kernel/dnbd3.h
@@ -74,25 +74,7 @@ struct dnbd3_server {
uint64_t rtts[4];
uint64_t avg_rtt;
uint16_t protocol_version;
- uint16_t failures; // TODO failures runterzaehlen wenn wieder verbindung moeglich, seltener messen bei hohem failure count
-
- /*
- * TODO would this help?
- * uint8_t failures[4]
- * uint8_t avg_failures;
- *
- * in timer, calculate each x iterations average over failure array
- * then move elements in array to left
- * for (i = 3; i > 0; i--) {
- * server->failures[i] = server->failures[i - 1]
- * }
- * server->failures[0] = 0;
- * failures always go to failures[0] / *failures
- *
- * - is this to much effort?
- * - what are the benefits?
- * - could increase the rtt e.g. (rtt = rtt * failures)
- */
+ uint16_t failures;
};
/**
@@ -145,7 +127,7 @@ struct dnbd3_sock {
* @update_available: 'true' if the rid has changes
* @use_server_provided_alts: 'true' if the alt_servers array is upated by the
* alternatives provided by the server
- * @rid: the revision ID? TODO
+ * @rid: the revision ID
* @reported_size: the size of the image
* @panic_worker: worker to handle panics and to connect if all connections are
* down
@@ -195,18 +177,16 @@ struct dnbd3_device {
* @requed: 'true' if the command is requed
*/
struct dnbd3_cmd {
- //TODO do we want the socket here (index)?
struct dnbd3_device *dnbd3;
struct mutex lock;
uint32_t cookie;
- blk_status_t status;
+ uint32_t index;
bool requed;
};
-#define dnbd3_avg_rtt(server) \
- (( (server)->rtts[0] + (server)->rtts[1] \
- + (server)->rtts[2] + (server)->rtts[3] ) / 4 )
+
+
#define dnbd3_set_rtt_unreachable(server) \
(server)->rtts[0] = (server)->rtts[1] = (server)->rtts[2] \
@@ -216,8 +196,8 @@ struct dnbd3_cmd {
#define dnbd3_set_rtt_unknown(server) \
(server)->rtts[0] = (server)->rtts[1] = (server)->rtts[2] \
- = (server)->rtts[3] = (server)->avg_rtt = \
- RTT_UNKNOWN;
+ = (server)->rtts[3] = 0;\
+ (server)->avg_rtt = RTT_UNKNOWN;
/**
diff --git a/src/kernel/mq.c b/src/kernel/mq.c
index 946e395..b1c1e99 100644
--- a/src/kernel/mq.c
+++ b/src/kernel/mq.c
@@ -32,21 +32,24 @@
*/
static void dnbd3_busy_iter(struct request *req, void *priv, bool arg2)
{
- bool *is_busy = (bool *) priv;
- *is_busy = true;
+ struct dnbd3_cmd *cmd = blk_mq_rq_to_pdu(req);
+ unsigned long *busy = (unsigned long *) priv;
+ set_bit(cmd->index, busy);
}
/**
* dnbd3_is_mq_busy - check if mq is busy
* @dev: the device
+ *
+ * sets bit to 1, where socket is busy
*/
-bool dnbd3_is_mq_busy(struct dnbd3_device *dev)
+unsigned long dnbd3_is_mq_busy(struct dnbd3_device *dev)
{
struct blk_mq_tag_set *set = &dev->tag_set;
- bool is_busy = false;
+ unsigned long busy = 0;
- blk_mq_tagset_busy_iter(set, dnbd3_busy_iter, &is_busy);
+ blk_mq_tagset_busy_iter(set, dnbd3_busy_iter, &busy);
/*
* just for demonstration
@@ -64,7 +67,7 @@ bool dnbd3_is_mq_busy(struct dnbd3_device *dev)
}
*/
- return is_busy;
+ return busy;
}
@@ -92,20 +95,6 @@ void dnbd3_end_cmd(struct dnbd3_cmd *cmd, blk_status_t error)
blk_mq_end_request(req, error);
}
-/**
- * dnbd3_is_any_sock_alive - check if any socket is alive
- * @cmd: the command
- */
-static bool dnbd3_is_any_sock_alive(struct dnbd3_cmd *cmd) {
- int i;
- for (i = 0; i < NUMBER_CONNECTIONS; i++) {
- if (dnbd3_is_sock_alive(cmd->dnbd3->socks[i]) &&
- !cmd->dnbd3->socks->panic) {
- return true;
- }
- }
- return false;
-}
/**
* dnbd3_handle_cmd - handles a mq command
@@ -140,8 +129,6 @@ static int dnbd3_handle_cmd(struct dnbd3_cmd *cmd, int index)
}
}
- cmd->status = BLK_STS_OK;
-
mutex_lock(&sock->tx_lock);
if (unlikely(!sock->sock)) {
mutex_unlock(&sock->tx_lock);
@@ -181,6 +168,7 @@ static blk_status_t dnbd3_queue_rq(struct blk_mq_hw_ctx *hctx,
mutex_lock(&cmd->lock);
cmd->requed = false;
+ cmd->index = hctx->queue_num;
ret = dnbd3_handle_cmd(cmd, hctx->queue_num);
if (ret < 0) {
@@ -234,8 +222,6 @@ static enum blk_eh_timer_return dnbd3_xmit_timeout(struct request *req,
}
error_dev(dev, "connection timed out");
- cmd->status = BLK_STS_IOERR;
-// blk_mq_complete_request(req);
dnbd3_end_cmd(cmd, BLK_STS_TIMEOUT);
mutex_unlock(&cmd->lock);
return BLK_EH_DONE;
diff --git a/src/kernel/mq.h b/src/kernel/mq.h
index 74f4f68..821fd91 100644
--- a/src/kernel/mq.h
+++ b/src/kernel/mq.h
@@ -26,8 +26,10 @@
/**
* dnbd3_is_mq_busy - check if mq is busy
* @dev: the device
+ *
+ * sets bit to 1, where socket is busy
*/
-bool dnbd3_is_mq_busy(struct dnbd3_device *dev);
+unsigned long dnbd3_is_mq_busy(struct dnbd3_device *dev);
/**
* dnbd3_requeue_cmd - requeue a command once
diff --git a/src/kernel/net.c b/src/kernel/net.c
index 79c860f..1207d0a 100644
--- a/src/kernel/net.c
+++ b/src/kernel/net.c
@@ -73,6 +73,22 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
struct dnbd3_server * server);
static int dnbd3_socket_disconnect(struct dnbd3_sock *sock);
+static uint64_t dnbd3_average_rtt(struct dnbd3_server *server)
+{
+ int i, j = 0;
+ uint64_t avg = 0;
+ for (i = 0; i < 4; i++) {
+ avg += server->rtts[i];
+ j += server->rtts[i] == 0 ? 0 : 1;
+ }
+ if (avg == 0) {
+ return RTT_UNKNOWN;
+ } else {
+ avg = avg / j;
+ avg += server->failures * avg / 10;
+ return avg;
+ }
+}
/*
* Methods for request and receive commands
@@ -267,6 +283,42 @@ static int dnbd3_receive_cmd(struct dnbd3_sock *sock, dnbd3_reply_t *reply)
return result;
}
+static int dnbd3_clear_socket(struct dnbd3_sock *sock, dnbd3_reply_t *reply,
+ int remaining)
+{
+ int result = 0;
+ char *buf;
+ struct kvec iov;
+ struct msghdr msg;
+ dnbd3_init_msghdr(msg);
+ warn_sock(sock, "clearing socket %d bytes", remaining);
+ buf = kmalloc(RTT_BLOCK_SIZE, GFP_KERNEL);
+ if (!buf) {
+ error_sock(sock, "kmalloc failed");
+ return -EIO;
+ }
+ /* hold the tx_lock so no new requests are send */
+ mutex_lock(&sock->tx_lock);
+ iov.iov_base = buf;
+ iov.iov_len = RTT_BLOCK_SIZE;
+ while (remaining > 0) {
+ result = kernel_recvmsg(sock->sock, &msg, &iov, 1, iov.iov_len,
+ msg.msg_flags);
+ if (result <= 0) {
+ goto error;
+ }
+ remaining -= result;
+ }
+
+ debug_sock(sock, "cleared socket");
+error:
+ mutex_unlock(&sock->tx_lock);
+ if (buf) {
+ kfree(buf);
+ }
+ return result;
+}
+
/**
* dnbd3_receive_cmd_get_block_mq - receive a block for mq
* @sock: the socket where the request is received
@@ -312,8 +364,8 @@ static int dnbd3_receive_cmd_get_block_mq(struct dnbd3_sock *sock,
debug_sock(sock, "requeue request");
dnbd3_requeue_cmd(blk_mq_rq_to_pdu(req));
}
-// return -EIO;
- goto clear_socket;
+ dnbd3_clear_socket(sock, reply, remaining);
+ return -EIO;
}
cmd = blk_mq_rq_to_pdu(req);
@@ -322,8 +374,8 @@ static int dnbd3_receive_cmd_get_block_mq(struct dnbd3_sock *sock,
error_sock(sock, "double reply on req %p, cookie %u, handle cookie %u",
req, cmd->cookie, cookie);
mutex_unlock(&cmd->lock);
-// return -EIO;
- goto clear_socket;
+ dnbd3_clear_socket(sock, reply, remaining);
+ return -EIO;
}
rq_for_each_segment(bvec_inst, req, iter) {
@@ -343,7 +395,8 @@ static int dnbd3_receive_cmd_get_block_mq(struct dnbd3_sock *sock,
dnbd3_requeue_cmd(cmd);
mutex_unlock(&cmd->lock);
if (result >= 0) {
- goto clear_socket;
+ dnbd3_clear_socket(sock, reply, remaining);
+ return -EIO;
} else {
return result;
}
@@ -355,35 +408,10 @@ static int dnbd3_receive_cmd_get_block_mq(struct dnbd3_sock *sock,
mutex_unlock(&cmd->lock);
dnbd3_end_cmd(cmd, 0);
return result;
-clear_socket:
- warn_sock(sock, "caught an error while receiving block, clearing buffer");
- char *buf = kmalloc(RTT_BLOCK_SIZE, GFP_KERNEL);
- if (!buf) {
- error_sock(sock, "kmalloc failed");
- return -EIO;
- }
-
- iov.iov_base = buf;
- iov.iov_len = RTT_BLOCK_SIZE;
- while (remaining > 0) {
- result = kernel_recvmsg(sock->sock, &msg, &iov, 1, iov.iov_len,
- msg.msg_flags);
- if (result <= 0) {
- goto error;
- }
- remaining -= result;
- }
-
- debug_sock(sock, "cleared buffer %d bytes, reply size is %d", result,
- reply->size);
-error:
- if (buf) {
- kfree(buf);
- }
- return -EIO;
}
+
/**
* dnbd3_receive_cmd_get_block_test - receive a test block
* @sock: the socket where the request is received
@@ -620,26 +648,29 @@ static int dnbd3_receive_cmd_select_image(struct dnbd3_sock *sock,
static void dnbd3_timer(struct timer_list *arg)
{
struct dnbd3_device *dev;
+ unsigned long busy;
int i;
dev = container_of(arg, struct dnbd3_device, timer);
queue_work(dnbd3_wq, &dev->panic_worker);
+ busy = dnbd3_is_mq_busy(dev);
- if (!dnbd3_is_mq_busy(dev)) {
- if (dev->timer_count % TIMER_INTERVAL_KEEPALIVE_PACKET == 0) {
- for (i = 0; i < NUMBER_CONNECTIONS; i++) {
- if (dnbd3_is_sock_alive(dev->socks[i])) {
- queue_work(dnbd3_wq, &dev->socks[i].keepalive_worker);
- }
+ if (dev->timer_count % TIMER_INTERVAL_KEEPALIVE_PACKET == 0) {
+ for (i = 0; i < NUMBER_CONNECTIONS; i++) {
+ if (!test_bit(i, &busy) && dnbd3_is_sock_alive(dev->socks[i])) {
+ queue_work(dnbd3_wq, &dev->socks[i].keepalive_worker);
}
}
+ }
+
+ if (!busy) {
/* start after 4 seconds */
if (dev->timer_count % TIMER_INTERVAL_PROBE_NORMAL == 4) {
queue_work(dnbd3_wq, &dev->discovery_worker);
}
- dev->timer_count++;
}
+ dev->timer_count++;
dev->timer.expires = jiffies + HZ;
add_timer(&dev->timer);
}
@@ -739,8 +770,10 @@ static void dnbd3_keepalive_worker(struct work_struct *work)
{
struct dnbd3_sock *sock;
sock = container_of(work, struct dnbd3_sock, keepalive_worker);
- debug_sock(sock, "starting keepalive worker");
- dnbd3_send_request_cmd(sock, CMD_KEEPALIVE);
+ if (sock->server != NULL && !sock->panic) {
+ debug_sock(sock, "starting keepalive worker");
+ dnbd3_send_request_cmd(sock, CMD_KEEPALIVE);
+ }
}
/**
@@ -754,9 +787,9 @@ static int dnbd3_compare_servers(const void *lhs, const void *rhs) {
struct dnbd3_server *rhs_server = *((struct dnbd3_server **) rhs);
l = lhs_server->host.type != 0 ? lhs_server->avg_rtt
- : RTT_UNREACHABLE + 1;
+ : RTT_UNREACHABLE;
r = rhs_server->host.type != 0 ? rhs_server->avg_rtt
- : RTT_UNREACHABLE + 1;
+ : RTT_UNREACHABLE;
if (l < r) {
return -1;
} else if (l > r) {
@@ -998,7 +1031,7 @@ static int dnbd3_meassure_rtt(struct dnbd3_device *dev,
error:
sock.server->rtts[dev->discovery_count % 4] = rtt;
- sock.server->avg_rtt = dnbd3_avg_rtt(sock.server);
+ sock.server->avg_rtt = dnbd3_average_rtt(sock.server);
if (result <= 0) {
server->failures++;
}
@@ -1279,10 +1312,12 @@ static int dnbd3_socket_connect(struct dnbd3_sock *sock,
INIT_WORK(&sock->keepalive_worker, dnbd3_keepalive_worker);
- /* TODO not on every connect? request alternative servers receiver will handle this */
+ /* request alternative servers receiver will handle this */
if (dnbd3_send_request_cmd(sock, CMD_GET_SERVERS) <= 0) {
error_sock(sock, "failed to get servers in discovery");
}
+ /* failure count is divided on each successful connect */
+ server->failures = server->failures / 2;
return 0;
error:
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-11-21 19:06:45 +0100