From: Adam Kupczyk <akupczyk@ibm.com>
Date: Fri, 10 Mar 2023 07:53:27 +0000 (+0100)
Subject: os/bluestore: BlueFS: harmonize log read and writes modes
X-Git-Tag: v17.2.6~3^2
X-Git-Url: http://git-server-git.apps.pok.os.sepia.ceph.com/?a=commitdiff_plain;h=refs%2Fpull%2F50474%2Fhead;p=ceph.git

os/bluestore: BlueFS: harmonize log read and writes modes

BlueFS log has always been written in non-buffered mode.
Reading of it depends on bluefs_buffered_io option.
It is strongly suspected that this causes some wierd problems.

Possibly fixes: https://tracker.ceph.com/issues/54019

Signed-off-by: Adam Kupczyk <akupczyk@ibm.com>
(cherry picked from commit 80e9c5d1c328448f0ef2a836c8a312296e6f49d7)
---

diff --git a/src/os/bluestore/BlueFS.cc b/src/os/bluestore/BlueFS.cc
index a1bc6e99661b..64fbe1e88039 100644
--- a/src/os/bluestore/BlueFS.cc
+++ b/src/os/bluestore/BlueFS.cc
@@ -2217,13 +2217,16 @@ int64_t BlueFS::_read(
                  << std::hex << x_off << "~" << l << std::dec
                  << " of " << *p << dendl;
 	int r;
+	// when reading BlueFS log (only happens on startup) use non-buffered io
+	// it makes it in sync with logic in _flush_range()
+	bool use_buffered_io = h->file->fnode.ino == 1 ? false : cct->_conf->bluefs_buffered_io;
 	if (!cct->_conf->bluefs_check_for_zeros) {
 	  r = _bdev_read(p->bdev, p->offset + x_off, l, &buf->bl, ioc[p->bdev],
-			 cct->_conf->bluefs_buffered_io);
+			 use_buffered_io);
 	} else {
 	  r = _read_and_check(
 	    p->bdev, p->offset + x_off, l, &buf->bl, ioc[p->bdev],
-	    cct->_conf->bluefs_buffered_io);
+	    use_buffered_io);
 	}
 	logger->inc(l_bluefs_read_disk_count, 1);
 	logger->inc(l_bluefs_read_disk_bytes, l);