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| author | Joel Fernandes <joelagnelf@nvidia.com> | 2026-07-18 13:15:36 -0400 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2026-07-23 10:39:57 -0700 |
| commit | 34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch) | |
| tree | 7629759c1ec7148b95bc8ab3080df20a5ecd2273 /Documentation/admin-guide/device-mapper/delay.rst | |
| download | linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip | |
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop. As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.
Add the missing accumulation so that the printed value reflects the
actual counts.
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'Documentation/admin-guide/device-mapper/delay.rst')
| -rw-r--r-- | Documentation/admin-guide/device-mapper/delay.rst | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/Documentation/admin-guide/device-mapper/delay.rst b/Documentation/admin-guide/device-mapper/delay.rst new file mode 100644 index 000000000..a1e673c0e --- /dev/null +++ b/Documentation/admin-guide/device-mapper/delay.rst @@ -0,0 +1,54 @@ +======== +dm-delay +======== + +Device-Mapper's "delay" target delays reads and/or writes +and/or flushes and optionally maps them to different devices. + +Arguments:: + + <device> <offset> <delay> [<write_device> <write_offset> <write_delay> + [<flush_device> <flush_offset> <flush_delay>]] + +Table line has to either have 3, 6 or 9 arguments: + +3: apply offset and delay to read, write and flush operations on device + +6: apply offset and delay to device, also apply write_offset and write_delay + to write and flush operations on optionally different write_device with + optionally different sector offset + +9: same as 6 arguments plus define flush_offset and flush_delay explicitly + on/with optionally different flush_device/flush_offset. + +Offsets are specified in sectors. + +Delays are specified in milliseconds. + + +Example scripts +=============== + +:: + #!/bin/sh + # + # Create mapped device named "delayed" delaying read, write and flush operations for 500ms. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 500" + +:: + #!/bin/sh + # + # Create mapped device delaying write and flush operations for 400ms and + # splitting reads to device $1 but writes and flushes to different device $2 + # to different offsets of 2048 and 4096 sectors respectively. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 2048 0 $2 4096 400" + +:: + #!/bin/sh + # + # Create mapped device delaying reads for 50ms, writes for 100ms and flushes for 333ms + # onto the same backing device at offset 0 sectors. + # + dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 50 $2 0 100 $1 0 333" |
