From a2f1945ee3ce8eba02ef54168c72f3be8f2cebdc Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Fri, 22 Nov 2013 11:20:41 -0800 Subject: Add a unique "eid" value to all zevents Tagging each zevent with a unique monotonically increasing EID (Event IDentifier) provides the required infrastructure for a user space daemon to reliably process zevents. By writing the EID to persistent storage the daemon can safely resume where it left off in the event stream when it's restarted. Signed-off-by: Brian Behlendorf Signed-off-by: Chris Dunlap Issue #2 --- include/sys/fm/protocol.h | 1 + include/sys/fm/util.h | 1 + module/zfs/fm.c | 16 ++++++++++++++++ 3 files changed, 18 insertions(+) diff --git a/include/sys/fm/protocol.h b/include/sys/fm/protocol.h index 1ee221286..de05bb296 100644 --- a/include/sys/fm/protocol.h +++ b/include/sys/fm/protocol.h @@ -70,6 +70,7 @@ extern "C" { #define FM_EREPORT_DETECTOR "detector" #define FM_EREPORT_ENA "ena" #define FM_EREPORT_TIME "time" +#define FM_EREPORT_EID "eid" /* list.* event payload member names */ #define FM_LIST_EVENT_SIZE "list-sz" diff --git a/include/sys/fm/util.h b/include/sys/fm/util.h index 2f03d1011..9dfd436c1 100644 --- a/include/sys/fm/util.h +++ b/include/sys/fm/util.h @@ -81,6 +81,7 @@ typedef struct zevent_s { list_t ev_ze_list; /* " */ list_node_t ev_node; /* " */ zevent_cb_t *ev_cb; /* " */ + uint64_t ev_eid; } zevent_t; typedef struct zfs_zevent { diff --git a/module/zfs/fm.c b/module/zfs/fm.c index 002827b52..fe9223ff8 100644 --- a/module/zfs/fm.c +++ b/module/zfs/fm.c @@ -84,6 +84,14 @@ static int zevent_len_cur = 0; static int zevent_waiters = 0; static int zevent_flags = 0; +/* + * The EID (Event IDentifier) is used to uniquely tag a zevent when it is + * posted. The posted EIDs are monotonically increasing but not persistent. + * They will be reset to the initial value (1) each time the kernel module is + * loaded. + */ +static uint64_t zevent_eid = 0; + static kmutex_t zevent_lock; static list_t zevent_list; static kcondvar_t zevent_cv; @@ -498,6 +506,7 @@ zfs_zevent_post(nvlist_t *nvl, nvlist_t *detector, zevent_cb_t *cb) { int64_t tv_array[2]; timestruc_t tv; + uint64_t eid; size_t nvl_size = 0; zevent_t *ev; @@ -509,6 +518,12 @@ zfs_zevent_post(nvlist_t *nvl, nvlist_t *detector, zevent_cb_t *cb) return; } + eid = atomic_inc_64_nv(&zevent_eid); + if (nvlist_add_uint64(nvl, FM_EREPORT_EID, eid)) { + atomic_add_64(&erpt_kstat_data.erpt_set_failed.value.ui64, 1); + return; + } + (void) nvlist_size(nvl, &nvl_size, NV_ENCODE_NATIVE); if (nvl_size > ERPT_DATA_SZ || nvl_size == 0) { atomic_add_64(&erpt_kstat_data.erpt_dropped.value.ui64, 1); @@ -527,6 +542,7 @@ zfs_zevent_post(nvlist_t *nvl, nvlist_t *detector, zevent_cb_t *cb) ev->ev_nvl = nvl; ev->ev_detector = detector; ev->ev_cb = cb; + ev->ev_eid = eid; mutex_enter(&zevent_lock); zfs_zevent_insert(ev); -- cgit v1.2.3