d/numam-spdk
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

event: simplify sleep code in _spdk_reactor_run

Browse Source 
This sleep functionality is only really used by the stub
app currently.  nvmf target enables it, but it never
gets exercised since there is always a poller running on
each core.  So don't bother trying to count how long
the reactor didn't take action - try to sleep any time
where the loop did not take action.

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: If48cc3f989347811190de67a6423932d0b77cf45

Reviewed-on: https://review.gerrithub.io/423577
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: Changpeng Liu <changpeng.liu@intel.com>
Reviewed-by: Ben Walker <benjamin.walker@intel.com>
Chandler-Test-Pool: SPDK Automated Test System <sys_sgsw@intel.com>
This commit is contained in:
Jim Harris 2018-08-27 11:49:37 -07:00
parent e87352fa93
commit 5deb90b002
1 changed files with 18 additions and 32 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

50
lib/event/reactor.c
View File

@ -44,7 +44,6 @@
#define SPDK_MAX_SOCKET 64
#define SPDK_REACTOR_SPIN_TIME_USEC 1000
#define SPDK_EVENT_BATCH_SIZE 8
enum spdk_poller_state {
@ -463,7 +462,7 @@ spdk_reactor_get_tsc_stats(struct spdk_reactor_tsc_stats *tsc_stats, uint32_t co
* if (first timer poller has expired)
* run the first timer poller and reinsert it in the timer list
*
* if (idle for at least SPDK_REACTOR_SPIN_TIME_USEC)
* if (no action taken and sleep enabled)
* sleep until next timer poller is scheduled to expire
* \endcode
*
@ -474,8 +473,8 @@ _spdk_reactor_run(void *arg)
struct spdk_reactor *reactor = arg;
struct spdk_poller *poller;
uint32_t event_count;
uint64_t idle_started, now;
uint64_t spin_cycles, sleep_cycles;
uint64_t now;
uint64_t sleep_cycles;
uint32_t sleep_us;
int rc = -1;
char thread_name[32];
@ -490,9 +489,7 @@ _spdk_reactor_run(void *arg)
SPDK_NOTICELOG("Reactor started on core %u on socket %u\n", reactor->lcore,
reactor->socket_id);
spin_cycles = SPDK_REACTOR_SPIN_TIME_USEC * spdk_get_ticks_hz() / SPDK_SEC_TO_USEC;
sleep_cycles = reactor->max_delay_us * spdk_get_ticks_hz() / SPDK_SEC_TO_USEC;
idle_started = 0;
if (g_context_switch_monitor_enabled) {
_spdk_reactor_context_switch_monitor_start(reactor, NULL);
}
@ -554,38 +551,27 @@ _spdk_reactor_run(void *arg)
}
}
if (took_action) {
/* We were busy this loop iteration. Reset the idle timer. */
idle_started = 0;
} else if (idle_started == 0) {
/* We were previously busy, but this loop we took no actions. */
idle_started = spdk_get_ticks();
}
/* Determine if the thread can sleep */
if (sleep_cycles && idle_started) {
if (sleep_cycles && !took_action) {
now = spdk_get_ticks();
if (now >= (idle_started + spin_cycles)) {
sleep_us = reactor->max_delay_us;
sleep_us = reactor->max_delay_us;
poller = TAILQ_FIRST(&reactor->timer_pollers);
if (poller) {
/* There are timers registered, so don't sleep beyond
* when the next timer should fire */
if (poller->next_run_tick < (now + sleep_cycles)) {
if (poller->next_run_tick <= now) {
sleep_us = 0;
} else {
sleep_us = ((poller->next_run_tick - now) *
SPDK_SEC_TO_USEC) / spdk_get_ticks_hz();
}
poller = TAILQ_FIRST(&reactor->timer_pollers);
if (poller) {
/* There are timers registered, so don't sleep beyond
* when the next timer should fire */
if (poller->next_run_tick < (now + sleep_cycles)) {
if (poller->next_run_tick <= now) {
sleep_us = 0;
} else {
sleep_us = ((poller->next_run_tick - now) *
SPDK_SEC_TO_USEC) / spdk_get_ticks_hz();
}
}
}
if (sleep_us > 0) {
usleep(sleep_us);
}
if (sleep_us > 0) {
usleep(sleep_us);
}
}