mars/kernel/mars_client.c

1342 lines
33 KiB
C

/*
* MARS Long Distance Replication Software
*
* This file is part of MARS project: http://schoebel.github.io/mars/
*
* Copyright (C) 2010-2014 Thomas Schoebel-Theuer
* Copyright (C) 2011-2014 1&1 Internet AG
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
//#define BRICK_DEBUGGING
//#define MARS_DEBUGGING
//#define IO_DEBUGGING
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/jiffies.h>
#include "brick_wait.h"
#include "mars.h"
atomic_t client_sender_count = ATOMIC_INIT(0);
atomic_t client_receiver_count = ATOMIC_INIT(0);
///////////////////////// own type definitions ////////////////////////
#include "mars_client.h"
#define CLIENT_HASH_MAX (PAGE_SIZE / sizeof(struct list_head))
#define CLIENT_HASH_FN(x) \
((unsigned long)(x) % CLIENT_HASH_MAX)
int mars_client_info_timeout = 0;
int mars_client_abort = 10;
int max_client_channels = 2;
int max_client_bulk = 16;
/* //////////////////////// human readable numbers //////////////////////// */
#define MAX_HUMAN_NR 512
struct human_number_generator {
int hum_got;
u8 hum_wrap;
u8 hum_table[MAX_HUMAN_NR];
};
typedef u8 human_numbers_t[MAX_HUMAN_NR];
/* No locking necessary for now (no parallelism).
*/
static
int get_human_nr(struct human_number_generator *hum_gen)
{
int restarted = 0;
int searched = MAX_HUMAN_NR;
int res = (hum_gen->hum_got + 1) % MAX_HUMAN_NR;
restart:
while (searched-- >= 0) {
u8 cand = hum_gen->hum_table[res];
if (cand == hum_gen->hum_wrap) {
hum_gen->hum_table[res]++;
return res;
}
}
/* no candidate found: aliases are no longer avoidable */
hum_gen->hum_wrap = (hum_gen->hum_wrap + 1) % MAX_HUMAN_NR;
if (!restarted++)
goto restart;
/* fallback is now exhausted: we need to lie */
return 0;
}
static
void put_human_nr(struct human_number_generator *hum_gen, int nr)
{
int index = nr % MAX_HUMAN_NR;
hum_gen->hum_table[index] = hum_gen->hum_wrap;
}
static struct human_number_generator global_numbers;
///////////////////////// own helper functions ////////////////////////
static atomic_t sender_count = ATOMIC_INIT(0);
static
void _do_resubmit(struct client_channel *ch)
{
struct client_output *output = ch->output;
mb();
mutex_lock(&output->mutex);
if (!list_empty(&ch->wait_list)) {
struct list_head *first = READ_ONCE(ch->wait_list.next);
struct list_head *last = READ_ONCE(ch->wait_list.prev);
struct list_head *old_start = READ_ONCE(output->mref_list.next);
#define list_connect __list_del // the original routine has a misleading name: in reality it is more general
list_connect(&output->mref_list, first);
list_connect(last, old_start);
INIT_LIST_HEAD(&ch->wait_list);
}
mb();
mutex_unlock(&output->mutex);
}
static
void _kill_thread(struct client_threadinfo *ti, const char *name)
{
struct task_struct *thread = ti->thread;
if (thread) {
MARS_DBG("stopping %s thread\n", name);
ti->thread = NULL;
brick_thread_stop(thread);
}
}
static
void _kill_channel(struct client_channel *ch)
{
MARS_DBG("channel = %p\n", ch);
if (mars_socket_is_alive(&ch->socket)) {
MARS_DBG("shutdown socket\n");
mars_shutdown_socket(&ch->socket);
}
_kill_thread(&ch->receiver, "receiver");
if (ch->ch_state >= CL_CHANNEL_OPEN) {
MARS_DBG("close socket\n");
mars_put_socket(&ch->socket);
}
ch->recv_error = 0;
ch->ch_state = CL_CHANNEL_INITIALIZED;
/* Re-Submit any waiting requests
*/
_do_resubmit(ch);
}
static inline
void _kill_all_channels(struct client_bundle *bundle)
{
int i;
// first pass: shutdown in parallel without waiting
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch =&bundle->channel[i];
if (mars_socket_is_alive(&ch->socket)) {
MARS_DBG("shutdown socket %d\n", i);
mars_shutdown_socket(&ch->socket);
}
}
// separate pass (may wait)
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
_kill_channel(&bundle->channel[i]);
}
}
static
int receiver_thread(void *data);
static
int _setup_channel(struct client_bundle *bundle, int ch_nr)
{
struct client_channel *ch = &bundle->channel[ch_nr];
struct sockaddr_storage sockaddr = {};
int status;
ch->ch_nr = ch_nr;
if (unlikely(ch->receiver.thread)) {
MARS_WRN("receiver thread %d unexpectedly not dead\n", ch_nr);
_kill_thread(&ch->receiver, "receiver");
}
status = mars_create_sockaddr(&sockaddr, bundle->host);
if (unlikely(status < 0)) {
MARS_DBG("no sockaddr, status = %d\n", status);
goto done;
}
if (!bundle->params) {
struct sockaddr_in *_sockaddr = (void*)&sockaddr;
int offset = (int)ntohs(_sockaddr->sin_port) - mars_net_default_port;
if (offset < 0 || offset >= MARS_TRAFFIC_MAX)
offset = 0;
bundle->params = &mars_tcp_params[offset];
}
status = mars_create_socket(&ch->socket,
&sockaddr,
bundle->params,
false);
if (unlikely(status < 0)) {
MARS_DBG("no socket, status = %d\n", status);
goto really_done;
}
ch->socket.s_shutdown_on_err = true;
ch->socket.s_send_abort = mars_client_abort;
ch->socket.s_recv_abort = mars_client_abort;
ch->ch_state = CL_CHANNEL_OPEN;
ch->receiver.thread =
brick_thread_create(receiver_thread, ch,
"mars_rcv%d.%d/%d",
bundle->last_thread_nr,
ch->thread_restart_count++,
ch_nr);
if (unlikely(!ch->receiver.thread)) {
MARS_ERR("cannot start receiver thread %d, status = %d\n", ch_nr, status);
mars_shutdown_socket(&ch->socket);
ch->ch_state = CL_CHANNEL_INITIALIZED;
status = -ENOENT;
goto done;
}
ch->ch_state = CL_CHANNEL_USED;
atomic_inc(&client_receiver_count);
done:
if (status < 0) {
MARS_INF("cannot connect channel %d to remote host '%s' (status = %d) -- retrying\n",
ch_nr,
bundle->host ? bundle->host : "NULL",
status);
_kill_channel(ch);
}
really_done:
return status;
}
static
void _kill_bundle(struct client_bundle *bundle)
{
MARS_DBG("\n");
_kill_thread(&bundle->sender, "sender");
_kill_all_channels(bundle);
bundle->bundle_state = CL_BUNDLE_INITIALIZED;
}
static
void _maintain_bundle(struct client_bundle *bundle)
{
int i;
/* Re-open _any_ failed channel, even old ones.
* Reason: the number of channels might change during operation.
*/
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &bundle->channel[i];
if (ch->ch_state <= CL_CHANNEL_USED ||
(!ch->recv_error && mars_socket_is_alive(&ch->socket)))
continue;
MARS_DBG("killing channel %d\n", i);
_kill_channel(ch);
/* Re-setup including connect optiona is done later.
*/
}
}
static
struct client_channel *_get_channel(struct client_bundle *bundle, int min_channel, int max_channel)
{
struct client_channel *res;
long best_space;
int best_channel;
int i;
if (unlikely(max_channel <= 0 || max_channel > MAX_CLIENT_CHANNELS))
max_channel = MAX_CLIENT_CHANNELS;
if (unlikely(min_channel < 0 || min_channel >= max_channel)) {
min_channel = max_channel - 1;
if (unlikely(min_channel < 0))
min_channel = 0;
}
/* Use higher channels only when the first one is fully established */
if (max_channel > 1 &&
bundle->bundle_state >= CL_BUNDLE_RESPONSE_GOT &&
(bundle->channel[0].ch_state < CL_CHANNEL_CONNECTED)) {
max_channel = 1;
min_channel = 0;
}
/* Fast path.
* Speculate that the next channel is already usable,
* and that it has enough room.
*/
best_channel = bundle->old_channel + 1;
if (best_channel >= max_channel)
best_channel = min_channel;
res = &bundle->channel[best_channel];
if (res->ch_state >= CL_CHANNEL_CONNECTED &&
!res->recv_error &&
mars_socket_is_alive(&res->socket)) {
res->current_space = mars_socket_send_space_available(&res->socket);
if (res->current_space > (PAGE_SIZE + PAGE_SIZE / 4))
goto found;
}
/* Slow path. Do all the teady work.
*/
_maintain_bundle(bundle);
res = NULL;
best_space = -1;
best_channel = -1;
for (i = min_channel; i < max_channel; i++) {
struct client_channel *ch = &bundle->channel[i];
long this_space;
// create new channels when necessary
if (ch->ch_state < CL_CHANNEL_OPEN) {
int status;
// only create one new channel at a time
status = _setup_channel(bundle, i);
MARS_DBG("setup channel %d status=%d\n", i, status);
if (unlikely(status < 0))
continue;
this_space = mars_socket_send_space_available(&ch->socket);
ch->current_space = this_space;
/* Always prefer the newly opened channel */
res = ch;
best_channel = i;
break;
}
// select the best usable channel
this_space = mars_socket_send_space_available(&ch->socket);
ch->current_space = this_space;
if (this_space > best_space) {
best_space = this_space;
best_channel = i;
res = ch;
}
}
if (unlikely(!res)) {
MARS_WRN("cannot setup communication channel '%s' @%s\n",
bundle->path,
bundle->host);
goto done;
}
// send initial connect command
if (unlikely(res->ch_state < CL_CHANNEL_CONNECTED)) {
struct mars_cmd cmd = {
.cmd_code = CMD_CONNECT,
.cmd_str1 = bundle->path,
};
int status = mars_send_cmd(&res->socket, &cmd, false);
MARS_DBG("send CMD_CONNECT status = %d\n", status);
if (unlikely(status < 0)) {
MARS_WRN("connect '%s' @%s on channel %d failed, status = %d\n",
bundle->path,
bundle->host,
best_channel,
status);
_kill_channel(res);
res = NULL;
goto done;
}
res->ch_state = CL_CHANNEL_CONNECTED;
}
found:
bundle->old_channel = best_channel;
done:
return res;
}
static
int _request_info(struct client_channel *ch)
{
struct mars_cmd cmd = {
.cmd_code = CMD_GETINFO,
};
int status;
MARS_DBG("\n");
status = mars_send_cmd(&ch->socket, &cmd, false);
MARS_DBG("send CMD_GETINFO status = %d\n", status);
if (unlikely(status < 0)) {
MARS_DBG("send of getinfo failed, status = %d\n", status);
}
return status;
}
static int sender_thread(void *data);
static
int _setup_bundle(struct client_bundle *bundle, const char *str)
{
int status;
_kill_bundle(bundle);
brick_string_free(bundle->path);
bundle->path = brick_strdup(str);
status = -EINVAL;
bundle->host = strchr(bundle->path, '@');
if (unlikely(!bundle->host)) {
brick_string_free(bundle->path);
MARS_ERR("parameter string '%s' contains no remote specifier with '@'-syntax\n", str);
goto done;
}
*bundle->host++ = '\0';
bundle->last_thread_nr = get_human_nr(&global_numbers);
bundle->sender.thread =
brick_thread_create(sender_thread, bundle,
"mars_snd%d",
bundle->last_thread_nr);
if (unlikely(!bundle->sender.thread)) {
put_human_nr(&global_numbers, bundle->last_thread_nr);
MARS_ERR("cannot start sender thread for '%s' @%s\n",
bundle->path,
bundle->host);
status = -ENOENT;
goto done;
}
atomic_inc(&client_sender_count);
status = 0;
done:
MARS_DBG("status = %d\n", status);
return status;
}
static
long _compute_timeout(struct client_brick *brick, bool for_info)
{
long io_timeout = brick->power.io_timeout;
if (io_timeout <= 0)
io_timeout = global_net_io_timeout;
if (for_info && io_timeout > mars_client_info_timeout)
io_timeout = mars_client_info_timeout;
return io_timeout;
}
////////////////// own brick / input / output operations //////////////////
static int client_get_info(struct client_output *output, struct mars_info *info)
{
struct client_brick *brick = output->brick;
long io_timeout = _compute_timeout(brick, true);
int status;
if (!brick->power.led_on) {
if (output->got_info)
return 0;
output->get_info = true;
brick_wake_smp(&output->bundle.sender_event);
goto timeout;
}
output->get_info = true;
brick_wake_smp(&output->bundle.sender_event);
brick_wait_smp(output->info_event,
output->got_info,
io_timeout * HZ);
timeout:
status = -ETIME;
if (output->got_info) {
status = 0;
if (info) {
memcpy(info, &output->info, sizeof(*info));
output->got_info = false;
output->get_info = true;
}
}
return status;
}
static int client_ref_get(struct client_output *output, struct mref_object *mref)
{
int maxlen;
if (mref->ref_initialized) {
_mref_get(mref);
return mref->ref_len;
}
#if 1
/* Limit transfers to page boundaries.
* Currently, this is more restrictive than necessary.
* TODO: improve performance by doing better when possible.
* This needs help from the server in some efficient way.
*/
maxlen = PAGE_SIZE - (mref->ref_pos & (PAGE_SIZE-1));
if (mref->ref_len > maxlen)
mref->ref_len = maxlen;
#endif
if (!mref->ref_data) { // buffered IO
struct client_mref_aspect *mref_a = client_mref_get_aspect(output->brick, mref);
if (!mref_a)
return -EILSEQ;
mref_a->alloc_len = mref->ref_len;
mref->ref_data = brick_block_alloc(mref->ref_pos, mref->ref_len);
mref_a->do_dealloc = true;
}
_mref_get_first(mref);
return 0;
}
static void client_ref_put(struct client_output *output, struct mref_object *mref)
{
struct client_mref_aspect *mref_a;
if (!_mref_put(mref))
return;
mref_a = client_mref_get_aspect(output->brick, mref);
if (mref_a && mref_a->do_dealloc) {
brick_block_free(mref->ref_data, mref_a->alloc_len);
}
client_free_mref(mref);
}
static
void __io_insert(struct client_output *output,
struct client_mref_aspect *mref_a)
{
list_del(&mref_a->io_head);
list_add_tail(&mref_a->io_head, &output->mref_list);
}
static
void __hash_insert(struct client_output *output,
struct client_mref_aspect *mref_a)
{
struct mref_object *mref = mref_a->object;
int ref_id;
unsigned int hash_index;
if (mref_a->is_hashed)
return;
list_del(&mref_a->hash_head);
ref_id = READ_ONCE(mref->ref_id);
if (!ref_id) {
/* This may wrap around without harm */
ref_id = READ_ONCE(output->last_id) + 1;
if (!ref_id)
ref_id++;
WRITE_ONCE(output->last_id, ref_id);
WRITE_ONCE(mref->ref_id, ref_id);
}
hash_index = CLIENT_HASH_FN(ref_id);
list_add_tail(&mref_a->hash_head, &output->hash_table[hash_index]);
mref_a->is_hashed = true;
}
static
void _hash_insert(struct client_output *output,
struct client_mref_aspect *mref_a,
bool refresh_completed)
{
mb();
mutex_lock(&output->mutex);
if (refresh_completed)
mref_a->has_completed = false;
__io_insert(output, mref_a);
__hash_insert(output, mref_a);
mb();
mutex_unlock(&output->mutex);
}
static void client_ref_io(struct client_output *output, struct mref_object *mref)
{
struct client_brick *brick = output->brick;
struct client_mref_aspect *mref_a;
int error = -EINVAL;
mref_a = client_mref_get_aspect(brick, mref);
if (unlikely(!mref_a))
goto fatal;
while (brick->max_flying > 0 &&
atomic_read(&brick->fly_count) > brick->max_flying) {
MARS_IO("sleeping request pos = %lld len = %d flags = %ux (flying = %d)\n",
mref->ref_pos, mref->ref_len, mref->ref_flags,
atomic_read(&output->fly_count));
#ifdef IO_DEBUGGING
brick_msleep(3000);
#else
brick_msleep(1000 * 2 / HZ);
#endif
}
if (!(brick->power.led_on & brick->power.button))
goto error;
atomic_inc(&mars_global_io_flying);
atomic_inc(&brick->fly_count);
_mref_get(mref);
mref_a->submit_jiffies = jiffies;
_hash_insert(output, mref_a, true);
MARS_IO("added request id = %d pos = %lld len = %d flags = %ux (flying = %d)\n",
mref->ref_id, mref->ref_pos, mref->ref_len, mref->ref_flags,
atomic_read(&output->fly_count));
brick_wake_smp(&output->bundle.sender_event);
return;
error:
MARS_ERR("IO submission on dead instance\n");
mref_a->has_completed = true;
error = -ESHUTDOWN;
SIMPLE_CALLBACK(mref, error);
return;
fatal:
MARS_ERR("FATAL error = %d\n", error);
}
static
int receiver_thread(void *data)
{
struct client_channel *ch = data;
struct client_output *output = ch->output;
struct client_brick *brick = output->brick;
int status = 0;
atomic_inc(&brick->receiver_count);
while (brick->power.button && !brick_thread_should_stop()) {
struct mars_cmd cmd = {};
if (ch->recv_error) {
/* The protocol may be out of sync.
* Consume some data to avoid distributed deadlocks.
*/
(void)mars_recv_raw(&ch->socket, &cmd, 0, sizeof(cmd));
brick_msleep(100);
status = ch->recv_error;
continue;
}
status = mars_recv_cmd(&ch->socket, &cmd);
MARS_IO("got cmd = %d status = %d\n", cmd.cmd_code, status);
if (status <= 0) {
if (brick->power.button &&
!mars_socket_is_alive(&ch->socket)) {
MARS_DBG("socket is dead\n");
brick_msleep(1000);
continue;
}
goto done;
}
switch (cmd.cmd_code & CMD_FLAG_MASK) {
case CMD_NOP:
break;
case CMD_NOTIFY:
mars_trigger();
break;
case CMD_CONNECT:
if (cmd.cmd_int1 < 0) {
status = cmd.cmd_int1;
MARS_ERR("remote brick connect '%s' @%s failed, remote status = %d\n",
output->bundle.path,
output->bundle.host,
status);
goto done;
}
output->bundle.bundle_state = CL_BUNDLE_RESPONSE_GOT;
break;
case CMD_CB:
{
struct list_head *anchor;
struct list_head *tmp;
struct list_head *tmp_next;
struct mref_object *mref = NULL;
struct client_mref_aspect *mref_a = NULL;
unsigned long id = READ_ONCE(cmd.cmd_int1);
unsigned int hash_index = CLIENT_HASH_FN(id);
bool had_completed = false;
mutex_lock(&output->mutex);
anchor = &output->hash_table[hash_index];
for (tmp = READ_ONCE(anchor->next), tmp_next = READ_ONCE(tmp->next);
tmp != anchor;
tmp = tmp_next, tmp_next = READ_ONCE(tmp_next->next)) {
struct mref_object *tmp_mref;
struct client_mref_aspect *tmp_mref_a;
tmp_mref_a = container_of(tmp, struct client_mref_aspect, hash_head);
/* Treat any non-members of io lists as absent.
* This may happen during re-assignment to another io list.
*/
if (unlikely(list_empty(&tmp_mref_a->io_head)))
continue;
tmp_mref = tmp_mref_a->object;
CHECK_PTR(tmp_mref, err);
if (READ_ONCE(tmp_mref->ref_id) != cmd.cmd_int1)
continue;
mref_a = tmp_mref_a;
mref = tmp_mref;
list_del_init(&mref_a->hash_head);
mref_a->is_hashed = false;
list_del_init(&mref_a->io_head);
/* Networking produces inherent races between re-submission and
* completion. Compensate them here.
*/
had_completed = mref_a->has_completed;
mref_a->has_completed = true;
break;
err:
mutex_unlock(&output->mutex);
status = -EBADR;
goto done;
}
mb();
mutex_unlock(&output->mutex);
if (unlikely(!mref || !mref_a)) {
MARS_WRN("got unknown callback id %d on '%s' @%s\n",
cmd.cmd_int1,
output->bundle.path,
output->bundle.host);
// try to consume the corresponding payload
mref = client_alloc_mref(output->brick);
status = mars_recv_cb(&ch->socket, mref, &cmd);
client_free_mref(mref);
goto done;
}
MARS_IO("got callback id = %d, old pos = %lld len = %d flags = %ux\n",
mref->ref_id, mref->ref_pos, mref->ref_len,
mref->ref_flags);
status = mars_recv_cb(&ch->socket, mref, &cmd);
MARS_IO("new status = %d, pos = %lld len = %d flags = %ux\n",
status, mref->ref_pos, mref->ref_len,
mref->ref_flags);
if (unlikely(status < 0)) {
MARS_WRN("interrupted data transfer during callback on '%s' @%s, status = %d\n",
output->bundle.path,
output->bundle.host,
status);
if (had_completed)
goto has_finished;
_hash_insert(output, mref_a, true);
goto done;
}
if (mref->_object_cb.cb_error < 0) {
MARS_DBG("ERROR %d\n", mref->_object_cb.cb_error);
}
if (!had_completed) {
SIMPLE_CALLBACK(mref, mref->_object_cb.cb_error);
}
has_finished:
client_ref_put(output, mref);
atomic_dec(&output->brick->fly_count);
atomic_dec(&mars_global_io_flying);
break;
}
case CMD_GETINFO:
status = mars_recv_struct(&ch->socket, &output->info, mars_info_meta);
if (status < 0) {
MARS_WRN("got bad info from remote '%s' @%s, status = %d\n",
output->bundle.path,
output->bundle.host,
status);
goto done;
}
output->got_info = true;
brick_wake_smp(&output->info_event);
break;
default:
MARS_ERR("got bad command %d from remote '%s' @%s, terminating.\n",
cmd.cmd_code,
output->bundle.path,
output->bundle.host);
status = -EBADR;
goto done;
}
done:
brick_string_free(cmd.cmd_str1);
brick_string_free(cmd.cmd_str2);
if (unlikely(status < 0)) {
if (!ch->recv_error) {
MARS_DBG("signalling recv_error = %d\n", status);
ch->recv_error = status;
}
brick_msleep(100);
}
// wake up sender in any case
brick_wake_smp(&output->bundle.sender_event);
}
if (unlikely(status < 0)) {
MARS_WRN("receiver thread '%s' @%s terminated with status = %d\n",
output->bundle.path,
output->bundle.host,
status);
}
mars_shutdown_socket(&ch->socket);
atomic_dec(&brick->receiver_count);
atomic_dec(&client_receiver_count);
mars_trigger();
return status;
}
static
void _do_timeout(struct client_output *output, struct list_head *anchor, int *rounds, bool force)
{
struct client_brick *brick = output->brick;
struct list_head *tmp;
struct list_head *prev;
long io_timeout = _compute_timeout(brick, false);
int i;
if (list_empty(anchor))
return;
if (!mars_net_is_alive)
force = true;
if (!force && io_timeout <= 0) {
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &output->bundle.channel[i];
ch->socket.s_send_abort = mars_client_abort;
ch->socket.s_recv_abort = mars_client_abort;
}
return;
}
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &output->bundle.channel[i];
ch->socket.s_send_abort = 1;
ch->socket.s_recv_abort = 1;
}
io_timeout *= HZ;
mutex_lock(&output->mutex);
for (tmp = READ_ONCE(anchor->prev), prev = READ_ONCE(tmp->prev);
tmp != anchor;
tmp = prev, prev = READ_ONCE(tmp->prev)) {
struct client_mref_aspect *mref_a;
struct mref_object *mref;
mref_a = container_of(tmp, struct client_mref_aspect, io_head);
if (!force &&
!time_is_before_jiffies(mref_a->submit_jiffies + io_timeout)) {
break;
}
/* Race compensation: skip already completed requests */
if (mref_a->has_completed)
continue;
list_del_init(&mref_a->hash_head);
mref_a->is_hashed = false;
list_del_init(&mref_a->io_head);
mref_a->has_completed = true;
mref = mref_a->object;
if (unlikely(!(*rounds)++)) {
MARS_WRN("'%s' @%s timeout after %ld: signalling IO error at pos = %lld len = %d\n",
output->bundle.path,
output->bundle.host,
io_timeout,
mref->ref_pos,
mref->ref_len);
}
atomic_inc(&brick->timeout_count);
SIMPLE_CALLBACK(mref, -ETIME);
client_ref_put(output, mref);
atomic_dec(&brick->fly_count);
atomic_dec(&mars_global_io_flying);
}
mb();
mutex_unlock(&output->mutex);
}
static
void _do_timeout_all(struct client_output *output, bool force)
{
int rounds = 0;
int i;
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &output->bundle.channel[i];
if (ch->ch_state < CL_CHANNEL_USED)
continue;
_do_timeout(output, &ch->wait_list, &rounds, force);
}
_do_timeout(output, &output->mref_list, &rounds, force);
if (unlikely(rounds > 0)) {
MARS_WRN("'%s' @%s had %d timeouts, force = %d\n",
output->bundle.path,
output->bundle.host,
rounds,
force);
}
}
static int sender_thread(void *data)
{
struct client_bundle *bundle = data;
struct client_output *output = container_of(bundle, struct client_output, bundle);
struct client_brick *brick = output->brick;
struct client_channel *ch = NULL;
bool do_timeout = false;
bool cork = false;
bool old_cork = false;
int ch_skip = max_client_bulk;
int status = -ESHUTDOWN;
if (atomic_inc_return(&sender_count) == 1)
mars_limit_reset(&client_limiter);
atomic_inc(&brick->sender_count);
while (brick->power.button && !brick_thread_should_stop()) {
struct list_head *tmp = NULL;
struct client_mref_aspect *mref_a;
struct mref_object *mref;
int min_nr;
int max_nr;
// timeouting is a rather expensive operation, don't do it too often
if (do_timeout) {
do_timeout = false;
_maintain_bundle(bundle);
_do_timeout_all(output, false);
}
brick_wait_smp(bundle->sender_event,
!list_empty(&output->mref_list) ||
output->get_info,
2 * HZ);
if (output->get_info) {
if (ch && old_cork) {
/* flush old buffer */
old_cork = false;
mars_send_raw(&ch->socket, NULL, 0, false);
}
ch = _get_channel(bundle, 0, 1);
if (unlikely(!ch)) {
do_timeout = true;
brick_msleep(1000);
continue;
}
status = _request_info(ch);
if (unlikely(status < 0)) {
MARS_WRN("cannot send info request '%s' @%s, status = %d\n",
bundle->path,
bundle->host,
status);
do_timeout = true;
brick_msleep(1000);
continue;
}
output->get_info = false;
}
/* Grab the next mref from the queue
*/
mb();
mutex_lock(&output->mutex);
tmp = READ_ONCE(output->mref_list.next);
if (tmp == &output->mref_list) {
mutex_unlock(&output->mutex);
MARS_DBG("empty %d %d\n", output->get_info, brick_thread_should_stop());
do_timeout = true;
continue;
}
list_del_init(tmp);
// notice: hash_head remains in its list!
cork = !list_empty(&output->mref_list);
mb();
mutex_unlock(&output->mutex);
mref_a = container_of(tmp, struct client_mref_aspect, io_head);
mref = mref_a->object;
/* Limiting is not inteded for production, only for testing */
if (brick->limit_mode) {
int amount = (mref->ref_len - 1) / 1024 + 1;
mars_limit_sleep(&client_limiter, amount);
}
// try to spread reads over multiple channels....
min_nr = 0;
max_nr = max_client_channels;
if (!(mref->ref_flags & MREF_WRITE)) {
/* optionally separate reads from writes */
if (brick->separate_reads && max_nr > 1)
min_nr = 1;
} else if (!brick->allow_permuting_writes) {
max_nr = 1;
}
if (!ch || ch->recv_error ||
!mars_socket_is_alive(&ch->socket))
do_timeout = true;
if (do_timeout || ch->ch_nr >= max_nr || --ch_skip < 0) {
if (ch && old_cork) {
/* flush old buffer */
old_cork = false;
mars_send_raw(&ch->socket, NULL, 0, false);
}
ch = _get_channel(bundle, min_nr, max_nr);
if (unlikely(!ch)) {
// notice: this will re-assign hash_head without harm
_hash_insert(output, mref_a, false);
brick_msleep(1000);
continue;
}
/* estimate: add some headroom for overhead */
ch_skip = ch->current_space / PAGE_SIZE +
ch->current_space / (PAGE_SIZE * 8);
if (ch_skip > max_client_bulk)
ch_skip = max_client_bulk;
}
mb();
mutex_lock(&output->mutex);
list_add_tail(tmp, &ch->wait_list);
// notice: hash_head is already there!
mb();
mutex_unlock(&output->mutex);
mref->ref_flags |= enabled_net_compressions;
status = mars_send_mref(&ch->socket, mref, cork);
old_cork = cork;
if (unlikely(status < 0)) {
_hash_insert(output, mref_a, false);
do_timeout = true;
ch = NULL;
// retry submission on next occasion..
MARS_WRN("mref send '%s' @%s failed, status = %d\n",
bundle->path,
bundle->host,
status);
brick_msleep(100);
continue;
}
}
if (unlikely(status < 0)) {
MARS_WRN("sender thread '%s' @%s terminated with status = %d\n",
bundle->path,
bundle->host,
status);
}
_kill_all_channels(bundle);
/* Signal error on all pending IO requests.
* We have no other chance (except probably delaying
* this until destruction which is probably not what
* we want).
*/
_do_timeout_all(output, true);
if (!atomic_dec_return(&sender_count))
mars_limit_reset(&client_limiter);
atomic_dec(&brick->sender_count);
put_human_nr(&global_numbers, bundle->last_thread_nr);
brick_wake_smp(&bundle->sender_event);
MARS_DBG("sender terminated\n");
atomic_dec(&client_sender_count);
return status;
}
static int client_switch(struct client_brick *brick)
{
struct client_output *output = brick->outputs[0];
int status = 0;
if (brick->power.button) {
int socket_count = 0;
int i;
for (i = 0; i < MAX_CLIENT_CHANNELS; i++)
if (output->bundle.channel[i].ch_state >= CL_CHANNEL_CONNECTED)
socket_count++;
brick->socket_count = socket_count;
if (brick->power.led_on)
goto done;
mars_power_led_off((void*)brick, false);
if (!output->bundle.sender.thread) {
status = _setup_bundle(&output->bundle, brick->brick_name);
if (likely(status >= 0)) {
brick->connection_state = 1;
}
}
if (output->bundle.sender.thread && !output->get_info) {
client_get_info(output, NULL);
}
mars_power_led_on((void*)brick, output->got_info);
} else {
brick->socket_count = 0;
if (brick->power.led_off)
goto done;
mars_power_led_on((void*)brick, false);
if (atomic_read(&brick->sender_count))
goto done;
_kill_bundle(&output->bundle);
if (atomic_read(&brick->receiver_count))
goto done;
_do_timeout_all(output, true);
output->got_info = false;
brick->connection_state = 0;
mars_power_led_off((void*)brick, !output->bundle.sender.thread);
mars_remote_trigger(MARS_TRIGGER_LOCAL | MARS_TRIGGER_FROM_REMOTE);
}
done:
return status;
}
//////////////// informational / statistics ///////////////
static
char *client_statistics(struct client_brick *brick, int verbose)
{
struct client_output *output = brick->outputs[0];
char *res = brick_string_alloc(1024);
int socket_count = 0;
int i;
if (!res)
return NULL;
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &output->bundle.channel[i];
if (mars_socket_is_alive(&ch->socket))
socket_count++;
}
snprintf(res, 1024,
"get_info = %d "
"got_info = %d "
"socket_count = %d "
"max_flying = %d "
"io_timeout = %d | "
"timeout_count = %d "
"fly_count = %d\n",
output->get_info,
output->got_info,
socket_count,
brick->max_flying,
brick->power.io_timeout,
atomic_read(&brick->timeout_count),
atomic_read(&brick->fly_count));
return res;
}
static
void client_reset_statistics(struct client_brick *brick)
{
atomic_set(&brick->timeout_count, 0);
}
//////////////// object / aspect constructors / destructors ///////////////
static int client_mref_aspect_init_fn(struct generic_aspect *_ini)
{
struct client_mref_aspect *ini = (void*)_ini;
INIT_LIST_HEAD(&ini->io_head);
INIT_LIST_HEAD(&ini->hash_head);
return 0;
}
static void client_mref_aspect_exit_fn(struct generic_aspect *_ini)
{
struct client_mref_aspect *ini = (void*)_ini;
CHECK_HEAD_EMPTY(&ini->io_head);
CHECK_HEAD_EMPTY(&ini->hash_head);
}
MARS_MAKE_STATICS(client);
////////////////////// brick constructors / destructors ////////////////////
static int client_brick_construct(struct client_brick *brick)
{
return 0;
}
static int client_output_construct(struct client_output *output)
{
int i;
output->hash_table = brick_block_alloc(0, PAGE_SIZE);
for (i = 0; i < CLIENT_HASH_MAX; i++) {
INIT_LIST_HEAD(&output->hash_table[i]);
}
for (i = 0; i < MAX_CLIENT_CHANNELS; i++) {
struct client_channel *ch = &output->bundle.channel[i];
ch->output = output;
INIT_LIST_HEAD(&ch->wait_list);
}
init_waitqueue_head(&output->bundle.sender_event);
mutex_init(&output->mutex);
INIT_LIST_HEAD(&output->mref_list);
init_waitqueue_head(&output->info_event);
return 0;
}
static int client_output_destruct(struct client_output *output)
{
brick_string_free(output->bundle.path);
brick_block_free(output->hash_table, PAGE_SIZE);
mutex_destroy(&output->mutex);
return 0;
}
///////////////////////// static structs ////////////////////////
static struct client_brick_ops client_brick_ops = {
.brick_switch = client_switch,
.brick_statistics = client_statistics,
.reset_statistics = client_reset_statistics,
};
static struct client_output_ops client_output_ops = {
.mars_get_info = client_get_info,
.mref_get = client_ref_get,
.mref_put = client_ref_put,
.mref_io = client_ref_io,
};
const struct client_input_type client_input_type = {
.type_name = "client_input",
.input_size = sizeof(struct client_input),
};
static const struct client_input_type *client_input_types[] = {
&client_input_type,
};
const struct client_output_type client_output_type = {
.type_name = "client_output",
.output_size = sizeof(struct client_output),
.master_ops = &client_output_ops,
.output_construct = &client_output_construct,
.output_destruct = &client_output_destruct,
};
static const struct client_output_type *client_output_types[] = {
&client_output_type,
};
const struct client_brick_type client_brick_type = {
.type_name = "client_brick",
.brick_size = sizeof(struct client_brick),
.max_inputs = 0,
.max_outputs = 1,
.master_ops = &client_brick_ops,
.aspect_types = client_aspect_types,
.default_input_types = client_input_types,
.default_output_types = client_output_types,
.brick_construct = &client_brick_construct,
};
EXPORT_SYMBOL_GPL(client_brick_type);
////////////////// module init stuff /////////////////////////
struct mars_limiter client_limiter = {
/* Let all be zero */
};
EXPORT_SYMBOL_GPL(client_limiter);
int global_net_io_timeout = CONFIG_MARS_NETIO_TIMEOUT;
EXPORT_SYMBOL_GPL(global_net_io_timeout);
int __init init_mars_client(void)
{
MARS_INF("init_client()\n");
_client_brick_type = (void*)&client_brick_type;
return client_register_brick_type();
}
void exit_mars_client(void)
{
MARS_INF("exit_client()\n");
client_unregister_brick_type();
}