LU-13802 llite: add fail loc to force bio-dio switch

This adds a fail loc to force switching from BIO to DIO.

Test-Parameters: trivial
Test-Parameters:testlist=sanity env=ONLY=119j,ONLY_REPEAT=50
Signed-off-by: Patrick Farrell <patrick.farrell@oracle.com>
Change-Id: Icba303c32a86170af08a78c6b306db08e8ed6047
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/52593
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Shaun Tancheff <shaun.tancheff@hpe.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>

diff --git a/lustre/include/obd_support.h b/lustre/include/obd_support.h
index e94e8b3..ce97791 100644 (file)
--- a/lustre/include/obd_support.h
+++ b/lustre/include/obd_support.h
@@ -636,6 +636,7 @@ extern bool obd_enable_health_write;
 #define OBD_FAIL_LOV_COMP_MAGIC                            0x1426
 #define OBD_FAIL_LOV_COMP_PATTERN                  0x1427
 #define OBD_FAIL_LOV_INVALID_OSTIDX                0x1428
+#define OBD_FAIL_LLITE_FORCE_BIO_AS_DIO                    0x1429
 #define OBD_FAIL_LLITE_DELAY_TRUNCATE              0x1430
 #define OBD_FAIL_LLITE_READ_PAUSE                  0x1431
 #define OBD_FAIL_LLITE_FAULT_PAUSE                 0x1432

diff --git a/lustre/llite/file.c b/lustre/llite/file.c
index 668b870..660a966 100644 (file)
--- a/lustre/llite/file.c
+++ b/lustre/llite/file.c
@@ -2235,7 +2235,8 @@ static ssize_t ll_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
        args->u.normal.via_iocb = iocb;
 
        if (ll_hybrid_bio_dio_switch_check(file, iocb, CIT_READ,
-                                          iov_iter_count(to))) {
+                                          iov_iter_count(to)) ||
+           CFS_FAIL_CHECK(OBD_FAIL_LLITE_FORCE_BIO_AS_DIO)) {
 #ifdef IOCB_DIRECT
                iocb->ki_flags |= IOCB_DIRECT;
                CDEBUG(D_VFSTRACE, "switching to DIO\n");
@@ -2384,7 +2385,8 @@ static ssize_t ll_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
                GOTO(out, rc_normal = result);
 
        if (ll_hybrid_bio_dio_switch_check(file, iocb, CIT_WRITE,
-                                          iov_iter_count(from))) {
+                                          iov_iter_count(from)) ||
+           CFS_FAIL_CHECK(OBD_FAIL_LLITE_FORCE_BIO_AS_DIO)) {
 #ifdef IOCB_DIRECT
                iocb->ki_flags |= IOCB_DIRECT;
                CDEBUG(D_VFSTRACE, "switching to DIO\n");

diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index c035a66..ae3b3c4 100755 (executable)
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -14071,6 +14071,56 @@ test_119i()
 }
 run_test 119i "test unaligned aio at varying sizes"
 
+test_119j()
+{
+       (( $LINUX_VERSION_CODE > $(version_code 4.5.0) )) ||
+               skip "needs kernel > 4.5.0 for ki_flags support"
+
+       local rpcs
+       dd if=/dev/urandom of=$DIR/$tfile bs=8 count=1 || error "(0) dd failed"
+       sync
+       $LCTL set_param -n osc.*.rpc_stats=0
+       # Read from page cache, does not generate an rpc
+       dd if=$DIR/$tfile of=/dev/null bs=8 count=1 || error "(1) dd failed"
+       $LCTL get_param osc.*.rpc_stats
+       rpcs=($($LCTL get_param -n 'osc.*.rpc_stats' |
+               sed -n '/pages per rpc/,/^$/p' |
+               awk '/'$pages':/ { reads += $2; writes += $6 }; \
+               END { print reads,writes }'))
+       [[ ${rpcs[0]} == 0 ]] ||
+               error "(3) ${rpcs[0]} != 0 read RPCs"
+
+       # Test hybrid IO read
+       # Force next BIO as DIO
+       # This forces an RPC to the server
+       #define OBD_FAIL_LLITE_FORCE_BIO_AS_DIO 0x1429
+       $LCTL set_param fail_loc=0x1429
+       dd if=$DIR/$tfile of=/dev/null bs=8 count=1 || error "(4) dd failed"
+       $LCTL get_param osc.*.rpc_stats
+       rpcs=($($LCTL get_param -n 'osc.*.rpc_stats' |
+               sed -n '/pages per rpc/,/^$/p' |
+               awk '/'$pages':/ { reads += $2; writes += $6 }; \
+               END { print reads,writes }'))
+       [[ ${rpcs[0]} == 1 ]] ||
+               error "(5) ${rpcs[0]} != 1 read RPCs"
+
+       # Test hybrid IO write
+       #define OBD_FAIL_LLITE_FORCE_BIO_AS_DIO 0x1429
+       $LCTL set_param fail_loc=0x1429
+       #NB: We do not check for 0 write RPCs in the BIO case because that
+       # would make the test racey vs cache flushing
+       # but the DIO case is guaranteed to generate 1 write RPC
+       dd if=/dev/zero of=$DIR/$tfile bs=8 count=1 || error "(6) dd failed"
+       $LCTL get_param osc.*.rpc_stats
+       rpcs=($($LCTL get_param -n 'osc.*.rpc_stats' |
+               sed -n '/pages per rpc/,/^$/p' |
+               awk '/'$pages':/ { reads += $2; writes += $6 }; \
+               END { print reads,writes }'))
+       [[ ${rpcs[1]} == 1 ]] ||
+               error "(7) ${rpcs[0]} != 1 read RPCs"
+}
+run_test 119j "basic tests of hybrid IO switching"
+
 test_120a() {
        [ $PARALLEL == "yes" ] && skip "skip parallel run"
        remote_mds_nodsh && skip "remote MDS with nodsh"