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MFC r263978:

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Make it possible to have multiple CTL worker threads.  Leave the default
of 1 for now.

Sponsored by:	The FreeBSD Foundation
This commit is contained in:
trasz 2014-05-07 06:22:51 +00:00
parent d026d687fc
commit 4ceefd197d
1 changed files with 40 additions and 29 deletions
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69
sys/cam/ctl/ctl.c
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@ -60,6 +60,7 @@ __FBSDID("$FreeBSD$");
#include <sys/ioccom.h>
#include <sys/queue.h>
#include <sys/sbuf.h>
#include <sys/smp.h>
#include <sys/endian.h>
#include <sys/sysctl.h>
@ -320,6 +321,10 @@ static int ctl_is_single = 1;
static int index_to_aps_page;
SYSCTL_NODE(_kern_cam, OID_AUTO, ctl, CTLFLAG_RD, 0, "CAM Target Layer");
static int worker_threads = 1;
TUNABLE_INT("kern.cam.ctl.worker_threads", &worker_threads);
SYSCTL_INT(_kern_cam_ctl, OID_AUTO, worker_threads, CTLFLAG_RDTUN,
&worker_threads, 1, "Number of worker threads");
/*
* Serial number (0x80), device id (0x83), and supported pages (0x00)
@ -950,10 +955,7 @@ ctl_init(void)
struct ctl_frontend *fe;
struct ctl_lun *lun;
uint8_t sc_id =0;
#if 0
int i;
#endif
int error, retval;
int i, error, retval;
//int isc_retval;
retval = 0;
@ -1085,17 +1087,35 @@ ctl_init(void)
mtx_unlock(&softc->ctl_lock);
#endif
error = kproc_create(ctl_work_thread, softc, &softc->work_thread, 0, 0,
"ctl_thrd");
if (error != 0) {
printf("error creating CTL work thread!\n");
mtx_lock(&softc->ctl_lock);
ctl_free_lun(lun);
mtx_unlock(&softc->ctl_lock);
ctl_pool_free(internal_pool);
ctl_pool_free(emergency_pool);
ctl_pool_free(other_pool);
return (error);
if (worker_threads > MAXCPU || worker_threads == 0) {
printf("invalid kern.cam.ctl.worker_threads value; "
"setting to 1");
worker_threads = 1;
} else if (worker_threads < 0) {
if (mp_ncpus > 2) {
/*
* Using more than two worker threads actually hurts
* performance due to lock contention.
*/
worker_threads = 2;
} else {
worker_threads = 1;
}
}
for (i = 0; i < worker_threads; i++) {
error = kproc_create(ctl_work_thread, softc, &softc->work_thread, 0, 0,
"ctl_thrd%d", i);
if (error != 0) {
printf("error creating CTL work thread!\n");
mtx_lock(&softc->ctl_lock);
ctl_free_lun(lun);
mtx_unlock(&softc->ctl_lock);
ctl_pool_free(internal_pool);
ctl_pool_free(emergency_pool);
ctl_pool_free(other_pool);
return (error);
}
}
if (bootverbose)
printf("ctl: CAM Target Layer loaded\n");
@ -12993,7 +13013,11 @@ ctl_work_thread(void *arg)
if (io != NULL) {
STAILQ_REMOVE_HEAD(&softc->rtr_queue, links);
mtx_unlock(&softc->ctl_lock);
goto execute;
retval = ctl_scsiio(&io->scsiio);
if (retval != CTL_RETVAL_COMPLETE)
CTL_DEBUG_PRINT(("ctl_scsiio failed\n"));
mtx_lock(&softc->ctl_lock);
continue;
}
}
io = (union ctl_io *)STAILQ_FIRST(&softc->incoming_queue);
@ -13024,19 +13048,6 @@ ctl_work_thread(void *arg)
/* Back to the top of the loop to see what woke us up. */
continue;
execute:
retval = ctl_scsiio(&io->scsiio);
switch (retval) {
case CTL_RETVAL_COMPLETE:
break;
default:
/*
* Probably need to make sure this doesn't happen.
*/
break;
}
mtx_lock(&softc->ctl_lock);
}
}