From 13d38690ca393216c5a24482e1ef6c13830805b5 Mon Sep 17 00:00:00 2001 From: Patrick Farrell Date: Fri, 27 Oct 2023 14:37:11 -0400 Subject: [PATCH] EX-7601 ofd: identify reads to round If the beginning or end of a client read is unaligned, we must round the locking. This patch identifies reads where this is required, the next patch will do the locking. Print a debug message when such an IO is found, but don't do anything different - yet. Signed-off-by: Patrick Farrell Change-Id: Ibdab35b733225b4b1349ef457f66ca37dcb2d9bf Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/52863 Tested-by: jenkins Tested-by: Maloo Reviewed-by: Andreas Dilger Reviewed-by: Artem Blagodarenko --- lustre/target/tgt_handler.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/lustre/target/tgt_handler.c b/lustre/target/tgt_handler.c index 13dafe0..68c555d 100644 --- a/lustre/target/tgt_handler.c +++ b/lustre/target/tgt_handler.c @@ -2308,7 +2308,9 @@ int tgt_brw_read(struct tgt_session_info *tsi) struct ost_body *repbody; struct ost_body *body; struct obd_ioobj *ioo; + struct ost_layout_compr *olc; const char *obd_name = exp->exp_obd->obd_name; + enum ll_compr_type type; int no_reply = 0; int npages_read; ktime_t kstart; @@ -2380,6 +2382,39 @@ int tgt_brw_read(struct tgt_session_info *tsi) local_nb = tbc->tbc_lnb; + olc = &body->oa.o_layout_compr; + type = olc->ol_compr_type; + if (type != LL_COMPR_TYPE_NONE) { + int nrbufs = ioo->ioo_bufcnt; + unsigned int chunk_log_bits; + __u64 chunk_start; + __u64 chunk_end; + int chunk_size; + __u64 io_start; + __u64 io_end; + + chunk_log_bits = olc->ol_compr_chunk_log_bits; + chunk_size = COMPR_GET_CHUNK_SIZE(chunk_log_bits); + + /* rnbs are in offset order, so we get the start of IO from the + * first and end of IO from the last + */ + io_start = remote_nb[0].rnb_offset; + io_end = remote_nb[nrbufs - 1].rnb_offset + + remote_nb[nrbufs - 1].rnb_len; + + chunk_start = round_down(io_start, chunk_size); + chunk_end = round_up(io_end, chunk_size); + + CDEBUG(D_SEC, + "io_start: %llu io_end: %llu, chunk_start %llu, chunk_end %llu\n", + io_start, io_end, chunk_start, chunk_end); + + /* the start or end of this IO is unaligned */ + if (io_start != chunk_start || io_end != chunk_end) + CDEBUG(D_SEC, "unaligned IO\n"); + } + rc = tgt_brw_lock(tsi->tsi_env, exp, &tsi->tsi_resid, ioo, remote_nb, &lockh, LCK_PR); if (rc != 0) -- 1.8.3.1