The branch main has been updated by imp: URL: https://cgit.FreeBSD.org/src/commit/?id=dd6123ebf02b86cee90b75e54fc755f6c20caebf
commit dd6123ebf02b86cee90b75e54fc755f6c20caebf Author: Warner Losh <[email protected]> AuthorDate: 2024-07-20 02:53:08 +0000 Commit: Warner Losh <[email protected]> CommitDate: 2024-07-20 02:53:37 +0000 cam/iosched: Log outlier latency events Log outlier latency events to devd. In addition to counting, this will allow analysis of whether the problem is confined to a specific block range, or if it's a more general problem. Sponsored by: Netflix Reviewed by: jhb Differential Revision: https://reviews.freebsd.org/D46036 --- sys/cam/cam_iosched.c | 30 ++++++++++++++++++++++++++++-- 1 file changed, 28 insertions(+), 2 deletions(-) diff --git a/sys/cam/cam_iosched.c b/sys/cam/cam_iosched.c index cfefc8098d18..28b5375ae246 100644 --- a/sys/cam/cam_iosched.c +++ b/sys/cam/cam_iosched.c @@ -1813,7 +1813,6 @@ cam_iosched_bio_complete(struct cam_iosched_softc *isc, struct bio *bp, if (isc->latfcn && isc->max_lat != 0 && sim_latency > isc->max_lat) isc->latfcn(isc->latarg, sim_latency, bp); } - #endif return retval; } @@ -1926,9 +1925,35 @@ static sbintime_t latencies[LAT_BUCKETS - 1] = { BUCKET_BASE << 18 /* 5,242,880us */ }; +#define CAM_IOSCHED_DEVD_MSG_SIZE 256 + +static void +cam_iosched_devctl_outlier(struct iop_stats *iop, sbintime_t sim_latency, + const struct bio *bp) +{ + daddr_t lba = bp->bio_pblkno; + daddr_t cnt = bp->bio_bcount / iop->softc->disk->d_sectorsize; + char *sbmsg; + struct sbuf sb; + + sbmsg = malloc(CAM_IOSCHED_DEVD_MSG_SIZE, M_CAMSCHED, M_NOWAIT); + if (sbmsg == NULL) + return; + sbuf_new(&sb, sbmsg, CAM_IOSCHED_DEVD_MSG_SIZE, SBUF_FIXEDLEN); + + sbuf_printf(&sb, "device=%s%d lba=%jd blocks=%jd latency=%jd", + iop->softc->periph->periph_name, + iop->softc->periph->unit_number, + lba, cnt, sbttons(sim_latency)); + if (sbuf_finish(&sb) == 0) + devctl_notify("CAM", "iosched", "latency", sbuf_data(&sb)); + sbuf_delete(&sb); + free(sbmsg, M_CAMSCHED); +} + static void cam_iosched_update(struct iop_stats *iop, sbintime_t sim_latency, - const struct bio *bp __unused) + const struct bio *bp) { sbintime_t y, deltasq, delta; int i; @@ -1938,6 +1963,7 @@ cam_iosched_update(struct iop_stats *iop, sbintime_t sim_latency, * configured threshold. */ if (sim_latency > iop->bad_latency) { + cam_iosched_devctl_outlier(iop, sim_latency, bp); iop->too_long++; }
