diff options
Diffstat (limited to 'module/zfs/spa_stats.c')
| -rw-r--r-- | module/zfs/spa_stats.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/module/zfs/spa_stats.c b/module/zfs/spa_stats.c index 3f137d9c7..fa1cf9e98 100644 --- a/module/zfs/spa_stats.c +++ b/module/zfs/spa_stats.c @@ -22,6 +22,8 @@ #include <sys/zfs_context.h> #include <sys/spa_impl.h> #include <sys/vdev_impl.h> +#include <sys/spa.h> +#include <zfs_comutil.h> /* * Keeps stats on last N reads per spa_t, disabled by default. @@ -997,6 +999,64 @@ spa_mmp_history_add(spa_t *spa, uint64_t txg, uint64_t timestamp, return ((void *)smh); } +static void * +spa_state_addr(kstat_t *ksp, loff_t n) +{ + return (ksp->ks_private); /* return the spa_t */ +} + +static int +spa_state_data(char *buf, size_t size, void *data) +{ + spa_t *spa = (spa_t *)data; + (void) snprintf(buf, size, "%s\n", spa_state_to_name(spa)); + return (0); +} + +/* + * Return the state of the pool in /proc/spl/kstat/zfs/<pool>/state. + * + * This is a lock-less read of the pool's state (unlike using 'zpool', which + * can potentially block for seconds). Because it doesn't block, it can useful + * as a pool heartbeat value. + */ +static void +spa_state_init(spa_t *spa) +{ + spa_stats_history_t *ssh = &spa->spa_stats.state; + char *name; + kstat_t *ksp; + + mutex_init(&ssh->lock, NULL, MUTEX_DEFAULT, NULL); + + name = kmem_asprintf("zfs/%s", spa_name(spa)); + ksp = kstat_create(name, 0, "state", "misc", + KSTAT_TYPE_RAW, 0, KSTAT_FLAG_VIRTUAL); + + ssh->kstat = ksp; + if (ksp) { + ksp->ks_lock = &ssh->lock; + ksp->ks_data = NULL; + ksp->ks_private = spa; + ksp->ks_flags |= KSTAT_FLAG_NO_HEADERS; + kstat_set_raw_ops(ksp, NULL, spa_state_data, spa_state_addr); + kstat_install(ksp); + } + + strfree(name); +} + +static void +spa_health_destroy(spa_t *spa) +{ + spa_stats_history_t *ssh = &spa->spa_stats.state; + kstat_t *ksp = ssh->kstat; + if (ksp) + kstat_delete(ksp); + + mutex_destroy(&ssh->lock); +} + void spa_stats_init(spa_t *spa) { @@ -1005,11 +1065,13 @@ spa_stats_init(spa_t *spa) spa_tx_assign_init(spa); spa_io_history_init(spa); spa_mmp_history_init(spa); + spa_state_init(spa); } void spa_stats_destroy(spa_t *spa) { + spa_health_destroy(spa); spa_tx_assign_destroy(spa); spa_txg_history_destroy(spa); spa_read_history_destroy(spa); |