This patch adds a new method of path state checking based on accounting
IO error. This is useful in many scenarios such as intermittent IO error
an a path due to network congestion, or a shaky link.
Three parameters are added for the admin: "path_io_err_sample_time",
"path_io_err_num_threshold" and "path_io_err_recovery_time".
If path_io_err_sample_time and path_io_err_recovery_time are set to a
value greater than 0, when a path fail event occurs due to an IO error,
multipathd will enqueue this path into a queue of which each member is
sent direct reading asynchronous io at a fixed sample rate of 100HZ. The
IO accounting process for a path will last for path_io_err_sample_time.
If the number of IO error on a particular path is greater than the
path_io_err_num_threshold, then the path will not reinstate for
This helps us place the path in delayed state if we hit a lot of
intermittent IO errors on a particular path due to network/target
issues and isolate such degraded path and allow the admin to rectify
the errors on a path.
Signed-off-by: Junxiong Guan <guanjunxiong@xxxxxxxxxx>
---
libmultipath/Makefile | 5 +-
libmultipath/config.h | 9 +
libmultipath/configure.c | 3 +
libmultipath/dict.c | 41 ++++
libmultipath/io_err_stat.c | 522 +++++++++++++++++++++++++++++++++++++++++++++
libmultipath/io_err_stat.h | 16 ++
libmultipath/propsel.c | 53 +++++
libmultipath/propsel.h | 3 +
libmultipath/structs.h | 5 +
libmultipath/uevent.c | 36 +++-
libmultipath/uevent.h | 2 +
multipath/multipath.conf.5 | 42 ++++
multipathd/main.c | 56 +++++
13 files changed, 789 insertions(+), 4 deletions(-)
create mode 100644 libmultipath/io_err_stat.c
create mode 100644 libmultipath/io_err_stat.h
diff --git a/libmultipath/Makefile b/libmultipath/Makefile
index b3244fc7..dce73afe 100644
--- a/libmultipath/Makefile
+++ b/libmultipath/Makefile
@@ -9,7 +9,7 @@ LIBS = $(DEVLIB).$(SONAME)
CFLAGS += $(LIB_CFLAGS) -I$(mpathcmddir)
-LIBDEPS += -lpthread -ldl -ldevmapper -ludev -L$(mpathcmddir) -lmpathcmd -lurcu
+LIBDEPS += -lpthread -ldl -ldevmapper -ludev -L$(mpathcmddir) -lmpathcmd -lurcu -laio
ifdef SYSTEMD
CFLAGS += -DUSE_SYSTEMD=$(SYSTEMD)
@@ -42,7 +42,8 @@ OBJS = memory.o parser.o vector.o devmapper.o callout.o \
pgpolicies.o debug.o defaults.o uevent.o time-util.o \
switchgroup.o uxsock.o print.o alias.o log_pthread.o \
log.o configure.o structs_vec.o sysfs.o prio.o checkers.o \
- lock.o waiter.o file.o wwids.o prioritizers/alua_rtpg.o
+ lock.o waiter.o file.o wwids.o prioritizers/alua_rtpg.o \
+ io_err_stat.o
all: $(LIBS)
diff --git a/libmultipath/config.h b/libmultipath/config.h
index ffc69b5f..347ff5ba 100644
--- a/libmultipath/config.h
+++ b/libmultipath/config.h
@@ -75,6 +75,9 @@ struct hwentry {
int san_path_err_threshold;
int san_path_err_forget_rate;
int san_path_err_recovery_time;
+ int path_io_err_sample_time;
+ int path_io_err_num_threshold;
+ int path_io_err_recovery_time;
int skip_kpartx;
int max_sectors_kb;
char * bl_product;
@@ -106,6 +109,9 @@ struct mpentry {
int san_path_err_threshold;
int san_path_err_forget_rate;
int san_path_err_recovery_time;
+ int path_io_err_sample_time;
+ int path_io_err_num_threshold;
+ int path_io_err_recovery_time;
int skip_kpartx;
int max_sectors_kb;
uid_t uid;
@@ -155,6 +161,9 @@ struct config {
int san_path_err_threshold;
int san_path_err_forget_rate;
int san_path_err_recovery_time;
+ int path_io_err_sample_time;
+ int path_io_err_num_threshold;
+ int path_io_err_recovery_time;
int uxsock_timeout;
int strict_timing;
int retrigger_tries;
diff --git a/libmultipath/configure.c b/libmultipath/configure.c
index 74b6f52a..ee3318df 100644
--- a/libmultipath/configure.c
+++ b/libmultipath/configure.c
@@ -298,6 +298,9 @@ int setup_map(struct multipath *mpp, char *params, int params_size)
select_san_path_err_threshold(conf, mpp);
select_san_path_err_forget_rate(conf, mpp);
select_san_path_err_recovery_time(conf, mpp);
+ select_path_io_err_sample_time(conf, mpp);
+ select_path_io_err_num_threshold(conf, mpp);
+ select_path_io_err_recovery_time(conf, mpp);
select_skip_kpartx(conf, mpp);
select_max_sectors_kb(conf, mpp);
diff --git a/libmultipath/dict.c b/libmultipath/dict.c
index 9dc10904..540f5019 100644
--- a/libmultipath/dict.c
+++ b/libmultipath/dict.c
@@ -1108,6 +1108,35 @@ declare_hw_handler(san_path_err_recovery_time, set_off_int_undef)
declare_hw_snprint(san_path_err_recovery_time, print_off_int_undef)
declare_mp_handler(san_path_err_recovery_time, set_off_int_undef)
declare_mp_snprint(san_path_err_recovery_time, print_off_int_undef)
+declare_def_handler(path_io_err_sample_time, set_off_int_undef)
+declare_def_snprint_defint(path_io_err_sample_time, print_off_int_undef,
+ DEFAULT_ERR_CHECKS)
+declare_ovr_handler(path_io_err_sample_time, set_off_int_undef)
+declare_ovr_snprint(path_io_err_sample_time, print_off_int_undef)
+declare_hw_handler(path_io_err_sample_time, set_off_int_undef)
+declare_hw_snprint(path_io_err_sample_time, print_off_int_undef)
+declare_mp_handler(path_io_err_sample_time, set_off_int_undef)
+declare_mp_snprint(path_io_err_sample_time, print_off_int_undef)
+declare_def_handler(path_io_err_num_threshold, set_off_int_undef)
+declare_def_snprint_defint(path_io_err_num_threshold, print_off_int_undef,
+ DEFAULT_ERR_CHECKS)
+declare_ovr_handler(path_io_err_num_threshold, set_off_int_undef)
+declare_ovr_snprint(path_io_err_num_threshold, print_off_int_undef)
+declare_hw_handler(path_io_err_num_threshold, set_off_int_undef)
+declare_hw_snprint(path_io_err_num_threshold, print_off_int_undef)
+declare_mp_handler(path_io_err_num_threshold, set_off_int_undef)
+declare_mp_snprint(path_io_err_num_threshold, print_off_int_undef)
+declare_def_handler(path_io_err_recovery_time, set_off_int_undef)
+declare_def_snprint_defint(path_io_err_recovery_time, print_off_int_undef,
+ DEFAULT_ERR_CHECKS)
+declare_ovr_handler(path_io_err_recovery_time, set_off_int_undef)
+declare_ovr_snprint(path_io_err_recovery_time, print_off_int_undef)
+declare_hw_handler(path_io_err_recovery_time, set_off_int_undef)
+declare_hw_snprint(path_io_err_recovery_time, print_off_int_undef)
+declare_mp_handler(path_io_err_recovery_time, set_off_int_undef)
+declare_mp_snprint(path_io_err_recovery_time, print_off_int_undef)
+
+
static int
def_uxsock_timeout_handler(struct config *conf, vector strvec)
{
@@ -1443,6 +1472,9 @@ init_keywords(vector keywords)
install_keyword("san_path_err_threshold", &def_san_path_err_threshold_handler, &snprint_def_san_path_err_threshold);
install_keyword("san_path_err_forget_rate", &def_san_path_err_forget_rate_handler, &snprint_def_san_path_err_forget_rate);
install_keyword("san_path_err_recovery_time", &def_san_path_err_recovery_time_handler, &snprint_def_san_path_err_recovery_time);
+ install_keyword("path_io_err_sample_time", &def_path_io_err_sample_time_handler, &snprint_def_path_io_err_sample_time);
+ install_keyword("path_io_err_num_threshold", &def_path_io_err_num_threshold_handler, &snprint_def_path_io_err_num_threshold);
+ install_keyword("path_io_err_recovery_time", &def_path_io_err_recovery_time_handler, &snprint_def_path_io_err_recovery_time);
install_keyword("find_multipaths", &def_find_multipaths_handler, &snprint_def_find_multipaths);
install_keyword("uxsock_timeout", &def_uxsock_timeout_handler, &snprint_def_uxsock_timeout);
@@ -1530,6 +1562,9 @@ init_keywords(vector keywords)
install_keyword("san_path_err_threshold", &hw_san_path_err_threshold_handler, &snprint_hw_san_path_err_threshold);
install_keyword("san_path_err_forget_rate", &hw_san_path_err_forget_rate_handler, &snprint_hw_san_path_err_forget_rate);
install_keyword("san_path_err_recovery_time", &hw_san_path_err_recovery_time_handler, &snprint_hw_san_path_err_recovery_time);
+ install_keyword("path_io_err_sample_time", &hw_path_io_err_sample_time_handler, &snprint_hw_path_io_err_sample_time);
+ install_keyword("path_io_err_num_threshold", &hw_path_io_err_num_threshold_handler, &snprint_hw_path_io_err_num_threshold);
+ install_keyword("path_io_err_recovery_time", &hw_path_io_err_recovery_time_handler, &snprint_hw_path_io_err_recovery_time);
install_keyword("skip_kpartx", &hw_skip_kpartx_handler, &snprint_hw_skip_kpartx);
install_keyword("max_sectors_kb", &hw_max_sectors_kb_handler, &snprint_hw_max_sectors_kb);
install_sublevel_end();
@@ -1563,6 +1598,9 @@ init_keywords(vector keywords)
install_keyword("san_path_err_threshold", &ovr_san_path_err_threshold_handler, &snprint_ovr_san_path_err_threshold);
install_keyword("san_path_err_forget_rate", &ovr_san_path_err_forget_rate_handler, &snprint_ovr_san_path_err_forget_rate);
install_keyword("san_path_err_recovery_time", &ovr_san_path_err_recovery_time_handler, &snprint_ovr_san_path_err_recovery_time);
+ install_keyword("path_io_err_sample_time", &ovr_path_io_err_sample_time_handler, &snprint_ovr_path_io_err_sample_time);
+ install_keyword("path_io_err_num_threshold", &ovr_path_io_err_num_threshold_handler, &snprint_ovr_path_io_err_num_threshold);
+ install_keyword("path_io_err_recovery_time", &ovr_path_io_err_recovery_time_handler, &snprint_ovr_path_io_err_recovery_time);
install_keyword("skip_kpartx", &ovr_skip_kpartx_handler, &snprint_ovr_skip_kpartx);
install_keyword("max_sectors_kb", &ovr_max_sectors_kb_handler, &snprint_ovr_max_sectors_kb);
@@ -1595,6 +1633,9 @@ init_keywords(vector keywords)
install_keyword("san_path_err_threshold", &mp_san_path_err_threshold_handler, &snprint_mp_san_path_err_threshold);
install_keyword("san_path_err_forget_rate", &mp_san_path_err_forget_rate_handler, &snprint_mp_san_path_err_forget_rate);
install_keyword("san_path_err_recovery_time", &mp_san_path_err_recovery_time_handler, &snprint_mp_san_path_err_recovery_time);
+ install_keyword("path_io_err_sample_time", &mp_path_io_err_sample_time_handler, &snprint_mp_path_io_err_sample_time);
+ install_keyword("path_io_err_num_threshold", &mp_path_io_err_num_threshold_handler, &snprint_mp_path_io_err_num_threshold);
+ install_keyword("path_io_err_recovery_time", &mp_path_io_err_recovery_time_handler, &snprint_mp_path_io_err_recovery_time);
install_keyword("skip_kpartx", &mp_skip_kpartx_handler, &snprint_mp_skip_kpartx);
install_keyword("max_sectors_kb", &mp_max_sectors_kb_handler, &snprint_mp_max_sectors_kb);
install_sublevel_end();
diff --git a/libmultipath/io_err_stat.c b/libmultipath/io_err_stat.c
new file mode 100644
index 00000000..b48a996a
--- /dev/null
+++ b/libmultipath/io_err_stat.c
@@ -0,0 +1,522 @@
+/*
+ * (C) Copyright HUAWEI Technology Corp. 2017, All Rights Reserved.
+ *
+ * io_err_stat.c
+ * version 1.0
+ *
+ * IO error stream statistic process for path failure event from kernel
+ *
+ * Author(s): Guan Junxiong 2017 <guanjunxiong@xxxxxxxxxx>
+ *
+ * This file is released under the GPL version 2, or any later version.
+ */
+
+#include <unistd.h>
+#include <pthread.h>
+#include <signal.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <linux/fs.h>
+#include <libaio.h>
+#include <errno.h>
+#include <sys/mman.h>
+
+#include "vector.h"
+#include "memory.h"
+#include "checkers.h"
+#include "config.h"
+#include "structs.h"
+#include "structs_vec.h"
+#include "devmapper.h"
+#include "debug.h"
+#include "lock.h"
+#include "time-util.h"
+#include "io_err_stat.h"
+
+#define IOTIMEOUT_SEC 60
+
+#define io_err_stat_log(prio, fmt, args...) \
+ condlog(prio, "io error statistic: " fmt, ##args)
+
+struct io_err_stat_pathvec {
+ pthread_mutex_t mutex;
+ vector pathvec;
+};
+
+struct dio_ctx {
+ struct timespec io_starttime;
+ int blksize;
+ unsigned char *buf;
+ unsigned char *ptr;
+ io_context_t ioctx;
+ struct iocb io;
+};
+
+struct io_err_stat_path {
+ char devname[FILE_NAME_SIZE];
+ int fd;
+ struct dio_ctx *pd_ctx;
+ int io_err_nr;
+ int io_nr;
+ struct timespec start_time;
+
+ int total_time;
+ int err_num_threshold;
+};
+
+pthread_t io_err_stat_thr;
+pthread_attr_t io_err_stat_attr;
+
+static struct io_err_stat_pathvec *paths;
+struct vectors *vecs;
+
+static void rcu_unregister(void *param)
+{
+ rcu_unregister_thread();
+}
+
+struct io_err_stat_path *find_err_path_by_dev(vector pathvec, char *dev)
+{
+ int i;
+ struct io_err_stat_path *pp;
+
+ if (!pathvec)
+ return NULL;
+ vector_foreach_slot(pathvec, pp, i)
+ if (!strcmp(pp->devname, dev))
+ return pp;
+
+ io_err_stat_log(4, "%s: not found in check queue", dev);
+
+ return NULL;
+}
+
+static int setup_directio_ctx(struct io_err_stat_path *p)
+{
+ unsigned long pgsize = getpagesize();
+ char fpath[FILE_NAME_SIZE+6];
+
+ snprintf(fpath, FILE_NAME_SIZE, "/dev/%s", p->devname);
+ if (p->fd < 0)
+ p->fd = open(fpath, O_RDONLY | O_DIRECT);
+ if (p->fd < 0)
+ return 1;
+
+ p->pd_ctx = MALLOC(sizeof(struct dio_ctx));
+ if (!p->pd_ctx)
+ goto fail_close;
+ if (io_setup(1, &p->pd_ctx->ioctx) != 0) {
+ io_err_stat_log(4, "io_setup failed for %s", fpath);
+ goto free_pdctx;
+ }
+
+ if (ioctl(p->fd, BLKBSZGET, &p->pd_ctx->blksize) < 0) {
+ io_err_stat_log(4, "cannot get blocksize, set default");
+ p->pd_ctx->blksize = 512;
+ }
+ /*
+ * Sanity check for block size
+ */
+ if (p->pd_ctx->blksize > 4096)
+ p->pd_ctx->blksize = 4096;
+ if (!p->pd_ctx->blksize)
+ goto io_destr;
+
+ p->pd_ctx->buf = (unsigned char *)MALLOC(p->pd_ctx->blksize + pgsize);
+ if (!p->pd_ctx->buf)
+ goto io_destr;
+
+ p->pd_ctx->ptr = (unsigned char *)(((unsigned long)p->pd_ctx->buf +
+ pgsize - 1) & (~(pgsize - 1)));
+
+ return 0;
+
+io_destr:
+ io_destroy(p->pd_ctx->ioctx);
+free_pdctx:
+ FREE(p->pd_ctx);
+fail_close:
+ close(p->fd);
+
+ return 1;
+}
+
+static void destroy_directio_ctx(struct io_err_stat_path *p)
+{
+ if (!p || !p->pd_ctx)
+ return;
+
+ if (p->pd_ctx->buf)
+ FREE(p->pd_ctx->buf);
+ if (p->pd_ctx->ioctx)
+ io_destroy(p->pd_ctx->ioctx);
+ FREE(p->pd_ctx);
+ if (p->fd > 0)
+ close(p->fd);
+}
+
+static struct io_err_stat_path *alloc_io_err_stat_path(void)
+{
+ struct io_err_stat_path *p;
+
+ p = (struct io_err_stat_path *)MALLOC(sizeof(*p));
+ if (!p)
+ return NULL;
+
+ memset(p->devname, 0, sizeof(p->devname));
+ p->io_err_nr = 0;
+ p->io_nr = 0;
+ p->total_time = 0;
+ p->start_time.tv_sec = 0;
+ p->start_time.tv_nsec = 0;
+ p->err_num_threshold = 0;
+ p->fd = -1;
+
+ return p;
+}
+
+static void free_io_err_stat_path(struct io_err_stat_path *p)
+{
+ if (p)
+ FREE(p);
+}
+
+static struct io_err_stat_pathvec *alloc_pathvec(void)
+{
+ struct io_err_stat_pathvec *p;
+ int r;
+
+ p = (struct io_err_stat_pathvec *)MALLOC(sizeof(*p));
+ if (!p)
+ return NULL;
+ p->pathvec = vector_alloc();
+ if (!p->pathvec)
+ goto out_free_struct_pathvec;
+ r = pthread_mutex_init(&p->mutex, NULL);
+ if (r)
+ goto out_free_member_pathvec;
+
+ return p;
+
+out_free_member_pathvec:
+ vector_free(p->pathvec);
+out_free_struct_pathvec:
+ FREE(p);
+ return NULL;
+}
+
+static void free_io_err_pathvec(struct io_err_stat_pathvec *p)
+{
+ struct io_err_stat_path *path;
+ int i;
+
+ if (!p)
+ return;
+ pthread_mutex_destroy(&p->mutex);
+ if (!p->pathvec) {
+ vector_foreach_slot(p->pathvec, path, i) {
+ destroy_directio_ctx(path);
+ free_io_err_stat_path(path);
+ }
+ vector_free(p->pathvec);
+ }
+ FREE(p);
+}
+
+int enqueue_io_err_stat_by_path(struct path *path)
+{
+ struct io_err_stat_path *p;
+
+ if (path->io_err_disable_reinstate) {
+ io_err_stat_log(3, "%s: reinstate is already disabled",
+ path->dev);
+ return 1;
+ }
+
+ if (!path->mpp)
+ return 1;
+ if (path->mpp->path_io_err_sample_time <= 0 ||
+ path->mpp->path_io_err_recovery_time <= 0 ||
+ path->mpp->path_io_err_num_threshold < 0) {
+ io_err_stat_log(4, "%s: parameter not set", path->mpp->alias);
+ return 1;
+ }
+
+ pthread_mutex_lock(&paths->mutex);
+ p = find_err_path_by_dev(paths->pathvec, path->dev);
+ if (p) {
+ pthread_mutex_unlock(&paths->mutex);
+ return 1;
+ }
+ pthread_mutex_unlock(&paths->mutex);
+
+ p = alloc_io_err_stat_path();
+ if (!p)
+ return 1;
+
+ memcpy(p->devname, path->dev, sizeof(p->devname));
+ p->total_time = path->mpp->path_io_err_sample_time;
+ p->err_num_threshold = path->mpp->path_io_err_num_threshold;
+
+ if (setup_directio_ctx(p))
+ goto free_ioerr_path;
+ pthread_mutex_lock(&paths->mutex);
+ if (!vector_alloc_slot(paths->pathvec))
+ goto unlock_destroy;
+ vector_set_slot(paths->pathvec, p);
+ pthread_mutex_unlock(&paths->mutex);
+
+ io_err_stat_log(2, "%s: enqueue path %s to check",
+ path->mpp->alias, path->dev);
+ return 0;
+
+unlock_destroy:
+ pthread_mutex_unlock(&paths->mutex);
+ destroy_directio_ctx(p);
+free_ioerr_path:
+ free_io_err_stat_path(p);
+
+ return 1;
+}
+
+int hit_io_err_recovery_time(struct path *pp)
+{
+ struct timespec curr_time;
+
+ if (pp->io_err_disable_reinstate == 0)
+ return 1;
+ if (clock_gettime(CLOCK_MONOTONIC, &curr_time) != 0)
+ return 1;
+ if (pp->mpp->nr_active == 0) {
+ io_err_stat_log(2, "%s: recover path early", pp->dev);
+ goto recover;
+ }
+ if ((curr_time.tv_sec - pp->io_err_dis_reinstate_time) >
+ pp->mpp->path_io_err_recovery_time) {
+ io_err_stat_log(2, "%s: recover path after %d seconds",
+ pp->dev, pp->mpp->path_io_err_sample_time);
+ goto recover;
+ }
+
+ return 1;
+
+recover:
+ pp->io_err_disable_reinstate = 0;
+ return 0;
+}
+
+static int delete_io_err_stat_by_addr(struct io_err_stat_path *p)
+{
+ int i;
+
+ i = find_slot(paths->pathvec, p);
+ if (i != -1)
+ vector_del_slot(paths->pathvec, i);
+
+ destroy_directio_ctx(p);
+ free_io_err_stat_path(p);
+
+ return 0;
+}
+
+static int check_async_io(struct vectors *vecs, struct io_err_stat_path *pp,
+ int rc)
+{
+ struct timespec currtime, difftime;
+ struct path *path;
+
+ switch (rc) {
+ case PATH_UNCHECKED:
+ break;
+ case PATH_UP:
+ break;
+ case PATH_DOWN:
+ pp->io_err_nr++;
+ break;
+ case PATH_TIMEOUT:
+ pp->io_err_nr++;
+ break;
+ case PATH_PENDING:
+ break;
+ default:
+ break;
+ }
+
+ if (clock_gettime(CLOCK_MONOTONIC, &currtime) != 0)
+ return 1;
+ timespecsub(&currtime, &pp->start_time, &difftime);
+ if (difftime.tv_sec < pp->total_time)
+ return 0;
+
+ io_err_stat_log(3, "check end for %s", pp->devname);
+
+ pthread_cleanup_push(cleanup_lock, &vecs->lock);
+ lock(&vecs->lock);
+ pthread_testcancel();
+ path = find_path_by_dev(vecs->pathvec, pp->devname);
+
+ if (!path) {
+ io_err_stat_log(3, "path %s not found'", pp->devname);
+ } else if (pp->io_err_nr <= pp->err_num_threshold) {
+ io_err_stat_log(3, "%s: (%d/%d) not hit threshold",
+ pp->devname, pp->io_err_nr, pp->io_nr);
+ } else if (path->mpp && path->mpp->nr_active > 1) {
+ dm_fail_path(path->mpp->alias, path->dev_t);
+ update_queue_mode_del_path(path->mpp);
+ io_err_stat_log(2, "%s: proacively fail dm path %s",
+ path->mpp->alias, path->dev);
+ path->io_err_disable_reinstate = 1;
+ path->io_err_dis_reinstate_time = currtime.tv_sec;
+ io_err_stat_log(3, "%s: to disable %s reinstate",
+ path->mpp->alias, path->dev);
+
+ /*
+ * schedule path check as soon as possible to
+ * update path state to delayed state
+ */
+ path->tick = 1;
+ } else {
+ io_err_stat_log(3, "%s: do nothing", pp->devname);
+ }
+ lock_cleanup_pop(vecs->lock);
+
+ delete_io_err_stat_by_addr(pp);
+
+ return 0;
+}
+
+static int send_async_io(struct io_err_stat_path *pp, int timeout_secs)
+{
+ struct timespec timeout = { .tv_nsec = 5 };
+ struct timespec curr_time, difftime;
+ struct io_event event;
+ int rc = PATH_UNCHECKED;
+ long r;
+
+ struct dio_ctx *ct = pp->pd_ctx;
+
+ if (!ct)
+ return rc;
+
+ if (ct->io_starttime.tv_nsec == 0 &&
+ ct->io_starttime.tv_sec == 0) {
+ struct iocb *ios[1] = { &ct->io };
+
+ memset(&ct->io, 0, sizeof(struct iocb));
+ io_prep_pread(&ct->io, pp->fd, ct->ptr, ct->blksize, 0);
+ if (io_submit(ct->ioctx, 1, ios) != 1) {
+ io_err_stat_log(3, "%s: io_submit error %i",
+ pp->devname, errno);
+ return rc;
+ }
+
+ if (clock_gettime(CLOCK_MONOTONIC, &ct->io_starttime) != 0) {
+ ct->io_starttime.tv_sec = 0;
+ ct->io_starttime.tv_nsec = 0;
+ }
+
+ if (pp->start_time.tv_sec == 0 && pp->start_time.tv_nsec == 0 &&
+ clock_gettime(CLOCK_MONOTONIC, &pp->start_time)) {
+ pp->start_time.tv_sec = 0;
+ pp->start_time.tv_nsec = 0;
+ return rc;
+ }
+ pp->io_nr++;
+ }
+
+ errno = 0;
+ r = io_getevents(ct->ioctx, 1L, 1L, &event, &timeout);
+ if (r < 0) {
+ io_err_stat_log(3, "%s: async io events returned %d (errno=%s)",
+ pp->devname, r, strerror(errno));
+ ct->io_starttime.tv_sec = 0;
+ ct->io_starttime.tv_nsec = 0;
+ rc = PATH_UNCHECKED;
+ } else if (r < 1L) {
+ if (clock_gettime(CLOCK_MONOTONIC, &curr_time) != 0)
+ curr_time.tv_sec = 0;
+ timespecsub(&curr_time, &ct->io_starttime, &difftime);
+
+ if (difftime.tv_sec > timeout_secs) {
+ struct iocb *ios[1] = { &ct->io };
+
+ io_err_stat_log(3, "%s: abort check on timeout",
+ pp->devname);
+ r = io_cancel(ct->ioctx, ios[0], &event);
+ if (r)
+ io_err_stat_log(3, "%s: io_cancel error %i",
+ pp->devname, errno);
+ else{
+ ct->io_starttime.tv_sec = 0;
+ ct->io_starttime.tv_nsec = 0;
+ }
+ rc = PATH_TIMEOUT;
+ } else {
+ rc = PATH_PENDING;
+ }
+ } else {
+ ct->io_starttime.tv_sec = 0;
+ ct->io_starttime.tv_nsec = 0;
+ rc = (event.res == ct->blksize) ? PATH_UP : PATH_DOWN;
+ }
+
+ return rc;
+}
+
+static void service_paths(void)
+{
+ struct io_err_stat_path *pp;
+ int i, rc;
+
+ pthread_mutex_lock(&paths->mutex);
+ vector_foreach_slot(paths->pathvec, pp, i) {
+ rc = send_async_io(pp, IOTIMEOUT_SEC);
+ check_async_io(vecs, pp, rc);
+ }
+ pthread_mutex_unlock(&paths->mutex);
+}
+
+static void *io_err_stat_loop(void *data)
+{
+ vecs = (struct vectors *)data;
+ pthread_cleanup_push(rcu_unregister, NULL);
+ rcu_register_thread();
+
+ mlockall(MCL_CURRENT | MCL_FUTURE);
+ while (1) {
+ service_paths();
+ usleep(10000); //TODO FIXME impact perf
+ }
+
+ pthread_cleanup_pop(1);
+ return NULL;
+}
+
+int start_io_err_stat_thread(void *data)
+{
+ paths = alloc_pathvec();
+ if (!paths)
+ return 1;
+
+ if (pthread_create(&io_err_stat_thr, &io_err_stat_attr,
+ io_err_stat_loop, data)) {
+ io_err_stat_log(0, "cannot create io_error statistic thread");
+ goto out;
+ }
+ io_err_stat_log(3, "thread started");
+ return 0;
+out:
+ free_io_err_pathvec(paths);
+ io_err_stat_log(0, "failed to start io_error statistic thread");
+ return 1;
+}
+
+void stop_io_err_stat_thread(void)
+{
+ pthread_cancel(io_err_stat_thr);
+ pthread_kill(io_err_stat_thr, SIGUSR2);
+
+ free_io_err_pathvec(paths);
+}
+
diff --git a/libmultipath/io_err_stat.h b/libmultipath/io_err_stat.h
new file mode 100644
index 00000000..20010785
--- /dev/null
+++ b/libmultipath/io_err_stat.h
@@ -0,0 +1,16 @@
+#ifndef _IO_ERR_STAT_H
+#define _IO_ERR_STAT_H
+
+#include "vector.h"
+#include "lock.h"
+
+
+extern pthread_attr_t io_err_stat_attr;
+
+int start_io_err_stat_thread(void *data);
+void stop_io_err_stat_thread(void);
+
+int enqueue_io_err_stat_by_path(struct path *path);
+int hit_io_err_recovery_time(struct path *pp);
+
+#endif /* _IO_ERR_STAT_H */
diff --git a/libmultipath/propsel.c b/libmultipath/propsel.c
index 175fbe11..9335777d 100644
--- a/libmultipath/propsel.c
+++ b/libmultipath/propsel.c
@@ -731,6 +731,7 @@ out:
return 0;
}
+
int select_san_path_err_threshold(struct config *conf, struct multipath *mp)
{
char *origin, buff[12];
@@ -761,6 +762,7 @@ out:
return 0;
}
+
int select_san_path_err_recovery_time(struct config *conf, struct multipath *mp)
{
char *origin, buff[12];
@@ -776,6 +778,57 @@ out:
return 0;
}
+
+int select_path_io_err_sample_time(struct config *conf, struct multipath *mp)
+{
+ char *origin, buff[12];
+
+ mp_set_mpe(path_io_err_sample_time);
+ mp_set_ovr(path_io_err_sample_time);
+ mp_set_hwe(path_io_err_sample_time);
+ mp_set_conf(path_io_err_sample_time);
+ mp_set_default(path_io_err_sample_time, DEFAULT_ERR_CHECKS);
+out:
+ print_off_int_undef(buff, 12, &mp->path_io_err_sample_time);
+ condlog(3, "%s: path_io_err_sample_time = %s %s", mp->alias, buff,
+ origin);
+ return 0;
+}
+
+int select_path_io_err_num_threshold(struct config *conf, struct multipath *mp)
+{
+ char *origin, buff[12];
+
+ mp_set_mpe(path_io_err_num_threshold);
+ mp_set_ovr(path_io_err_num_threshold);
+ mp_set_hwe(path_io_err_num_threshold);
+ mp_set_conf(path_io_err_num_threshold);
+ mp_set_default(path_io_err_num_threshold, DEFAULT_ERR_CHECKS);
+out:
+ print_off_int_undef(buff, 12, &mp->path_io_err_num_threshold);
+ condlog(3, "%s: path_io_err_num_threshold = %s %s", mp->alias, buff,
+ origin);
+ return 0;
+
+}
+
+int select_path_io_err_recovery_time(struct config *conf, struct multipath *mp)
+{
+ char *origin, buff[12];
+
+ mp_set_mpe(path_io_err_recovery_time);
+ mp_set_ovr(path_io_err_recovery_time);
+ mp_set_hwe(path_io_err_recovery_time);
+ mp_set_conf(path_io_err_recovery_time);
+ mp_set_default(path_io_err_recovery_time, DEFAULT_ERR_CHECKS);
+out:
+ print_off_int_undef(buff, 12, &mp->path_io_err_recovery_time);
+ condlog(3, "%s: path_io_err_recovery_time = %s %s", mp->alias, buff,
+ origin);
+ return 0;
+
+}
+
int select_skip_kpartx (struct config *conf, struct multipath * mp)
{
char *origin;
diff --git a/libmultipath/propsel.h b/libmultipath/propsel.h
index f8e96d85..181bd5e5 100644
--- a/libmultipath/propsel.h
+++ b/libmultipath/propsel.h
@@ -28,6 +28,9 @@ int select_max_sectors_kb (struct config *conf, struct multipath * mp);
int select_san_path_err_forget_rate(struct config *conf, struct multipath *mp);
int select_san_path_err_threshold(struct config *conf, struct multipath *mp);
int select_san_path_err_recovery_time(struct config *conf, struct multipath *mp);
+int select_path_io_err_sample_time(struct config *conf, struct multipath *mp);
+int select_path_io_err_num_threshold(struct config *conf, struct multipath *mp);
+int select_path_io_err_recovery_time(struct config *conf, struct multipath *mp);
void reconcile_features_with_options(const char *id, char **features,
int* no_path_retry,
int *retain_hwhandler);
diff --git a/libmultipath/structs.h b/libmultipath/structs.h
index 8ea984d9..f02cfdb9 100644
--- a/libmultipath/structs.h
+++ b/libmultipath/structs.h
@@ -235,6 +235,8 @@ struct path {
time_t dis_reinstate_time;
int disable_reinstate;
int san_path_err_forget_rate;
+ time_t io_err_dis_reinstate_time;
+ int io_err_disable_reinstate;
/* configlet pointers */
struct hwentry * hwe;
};
@@ -269,6 +271,9 @@ struct multipath {
int san_path_err_threshold;
int san_path_err_forget_rate;
int san_path_err_recovery_time;
+ int path_io_err_sample_time;
+ int path_io_err_num_threshold;
+ int path_io_err_recovery_time;
int skip_kpartx;
int max_sectors_kb;
int force_readonly;
diff --git a/libmultipath/uevent.c b/libmultipath/uevent.c
index eb44da56..56de1320 100644
--- a/libmultipath/uevent.c
+++ b/libmultipath/uevent.c
@@ -904,8 +904,8 @@ char *uevent_get_dm_name(struct uevent *uev)
int i;
for (i = 0; uev->envp[i] != NULL; i++) {
- if (!strncmp(uev->envp[i], "DM_NAME", 6) &&
- strlen(uev->envp[i]) > 7) {
+ if (!strncmp(uev->envp[i], "DM_NAME", 7) &&
+ strlen(uev->envp[i]) > 8) {
p = MALLOC(strlen(uev->envp[i] + 8) + 1);
strcpy(p, uev->envp[i] + 8);
break;
@@ -913,3 +913,35 @@ char *uevent_get_dm_name(struct uevent *uev)
}
return p;
}
+
+char *uevent_get_dm_path(struct uevent *uev)
+{
+ char *p = NULL;
+ int i;
+
+ for (i = 0; uev->envp[i] != NULL; i++) {
+ if (!strncmp(uev->envp[i], "DM_PATH", 7) &&
+ strlen(uev->envp[i]) > 8) {
+ p = MALLOC(strlen(uev->envp[i] + 8) + 1);
+ strcpy(p, uev->envp[i] + 8);
+ break;
+ }
+ }
+ return p;
+}
+
+char *uevent_get_dm_action(struct uevent *uev)
+{
+ char *p = NULL;
+ int i;
+
+ for (i = 0; uev->envp[i] != NULL; i++) {
+ if (!strncmp(uev->envp[i], "DM_ACTION", 9) &&
+ strlen(uev->envp[i]) > 10) {
+ p = MALLOC(strlen(uev->envp[i] + 10) + 1);
+ strcpy(p, uev->envp[i] + 10);
+ break;
+ }
+ }
+ return p;
+}
diff --git a/libmultipath/uevent.h b/libmultipath/uevent.h
index 61a42071..6f5af0af 100644
--- a/libmultipath/uevent.h
+++ b/libmultipath/uevent.h
@@ -37,5 +37,7 @@ int uevent_get_major(struct uevent *uev);
int uevent_get_minor(struct uevent *uev);
int uevent_get_disk_ro(struct uevent *uev);
char *uevent_get_dm_name(struct uevent *uev);
+char *uevent_get_dm_path(struct uevent *uev);
+char *uevent_get_dm_action(struct uevent *uev);
#endif /* _UEVENT_H */
diff --git a/multipath/multipath.conf.5 b/multipath/multipath.conf.5
index d9ac279f..6133d17d 100644
--- a/multipath/multipath.conf.5
+++ b/multipath/multipath.conf.5
@@ -849,6 +849,48 @@ The default is: \fBno\fR
.
.
.TP
+.B path_io_err_sample_time
+One of the three parameters of supporting path check based on accounting IO
+error such as intermittent error. If it is set to a value greater than 0,
+when a path fail event occurs due to an IO error, multipathd will enqueue this
+path into a queue of which members are sent direct reading aio at a fixed
+sample rate of 100HZ. The IO accounting process for a path will last for
+\fIpath_io_err_sample_time\fR. If the number of IO error on a particular path
+is greater than the \fIpath_io_err_num_threshold\fR, then the path will not
+reinstate for \fIpath_io_err_num_threshold\fR seconds unless there is only one
+active path.
+.RS
+.TP
+The default is: \fBno\fR
+.RE
+.
+.
+.TP
+.B path_io_err_num_threshold
+One of the three parameters of supporting path check based on accounting IO
+error such as intermittent error. Refer to \fIpath_io_err_sample_time\fR. If
+the number of IO errors on a particular path is greater than this parameter,
+then the path will not reinstate for \fIpath_io_err_num_threshold\fR seconds
+unless there is only one active path.
+.RS
+.TP
+The default is: \fBno\fR
+.RE
+.
+.
+.TP
+.B path_io_err_recovery_time
+One of the three parameters of supporting path check based on accounting IO
+error such as intermittent error. Refer to \fIpath_io_err_sample_time\fR. If
+this parameter is set to a positive value, the path which has many error will
+not reinsate till \fIpath_io_err_recovery_time\fR seconds.
+.RS
+.TP
+The default is: \fBno\fR
+.RE
+.
+.
+.TP
.B delay_watch_checks
If set to a value greater than 0, multipathd will watch paths that have
recently become valid for this many checks. If they fail again while they are
diff --git a/multipathd/main.c b/multipathd/main.c
index 4be2c579..d12e6fae 100644
--- a/multipathd/main.c
+++ b/multipathd/main.c
@@ -84,6 +84,7 @@ int uxsock_timeout;
#include "cli_handlers.h"
#include "lock.h"
#include "waiter.h"
+#include "io_err_stat.h"
#include "wwids.h"
#include "../third-party/valgrind/drd.h"
@@ -1050,6 +1051,41 @@ out:
}
static int
+uev_pathfail_check(struct uevent *uev, struct vectors *vecs)
+{
+ char *action = NULL, *devt = NULL;
+ struct path *pp;
+ int r;
+
+ action = uevent_get_dm_action(uev);
+ if (!action)
+ return 1;
+ if (strncmp(action, "PATH_FAILED", 11))
+ goto out;
+ devt = uevent_get_dm_path(uev);
+ if (!devt) {
+ condlog(3, "%s: No DM_PATH in uevent", uev->kernel);
+ goto out;
+ }
+
+ pthread_cleanup_push(cleanup_lock, &vecs->lock);
+ lock(&vecs->lock);
+ pthread_testcancel();
+ pp = find_path_by_devt(vecs->pathvec, devt);
+ r = enqueue_io_err_stat_by_path(pp);
+ lock_cleanup_pop(vecs->lock);
+
+ if (r)
+ condlog(3, "io_err_stat: fails to enqueue %s", pp->dev);
+ FREE(devt);
+ FREE(action);
+ return 0;
+out:
+ FREE(action);
+ return 1;
+}
+
+static int
map_discovery (struct vectors * vecs)
{
struct multipath * mpp;
@@ -1134,6 +1170,7 @@ uev_trigger (struct uevent * uev, void * trigger_data)
if (!strncmp(uev->kernel, "dm-", 3)) {
if (!strncmp(uev->action, "change", 6)) {
r = uev_add_map(uev, vecs);
+ uev_pathfail_check(uev, vecs);
goto out;
}
if (!strncmp(uev->action, "remove", 6)) {
@@ -1553,6 +1590,7 @@ static int check_path_reinstate_state(struct path * pp) {
condlog(2, "%s : hit error threshold. Delaying path reinstatement", pp->dev);
pp->dis_reinstate_time = curr_time.tv_sec;
pp->disable_reinstate = 1;
+
return 1;
} else {
return 0;
@@ -1684,6 +1722,16 @@ check_path (struct vectors * vecs, struct path * pp, int ticks)
return 1;
}
+ if (pp->io_err_disable_reinstate && hit_io_err_recovery_time(pp)) {
+ pp->state = PATH_DELAYED;
+ /*
+ * to reschedule as soon as possible,so that this path can
+ * be recoverd in time
+ */
+ pp->tick = 1;
+ return 1;
+ }
+
if ((newstate == PATH_UP || newstate == PATH_GHOST) &&
pp->wait_checks > 0) {
if (pp->mpp->nr_active > 0) {
@@ -2377,6 +2425,7 @@ child (void * param)
setup_thread_attr(&misc_attr, 64 * 1024, 0);
setup_thread_attr(&uevent_attr, DEFAULT_UEVENT_STACKSIZE * 1024, 0);
setup_thread_attr(&waiter_attr, 32 * 1024, 1);
+ setup_thread_attr(&io_err_stat_attr, 32 * 1024, 1);
if (logsink == 1) {
setup_thread_attr(&log_attr, 64 * 1024, 0);
@@ -2499,6 +2548,10 @@ child (void * param)
/*
* start threads
*/
+ rc = start_io_err_stat_thread(vecs);
+ if (rc)
+ goto failed;
+
if ((rc = pthread_create(&check_thr, &misc_attr, checkerloop, vecs))) {
condlog(0,"failed to create checker loop thread: %d", rc);
goto failed;
@@ -2548,6 +2601,8 @@ child (void * param)
remove_maps_and_stop_waiters(vecs);
unlock(&vecs->lock);
+ stop_io_err_stat_thread();
+
pthread_cancel(check_thr);
pthread_cancel(uevent_thr);
pthread_cancel(uxlsnr_thr);
@@ -2593,6 +2648,7 @@ child (void * param)
udev_unref(udev);
udev = NULL;
pthread_attr_destroy(&waiter_attr);
+ pthread_attr_destroy(&io_err_stat_attr);
#ifdef _DEBUG_
dbg_free_final(NULL);
#endif
--
2.11.1
--
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