| Message ID | 20181119004442.1942-1-stewart@linux.ibm.com |
|---|---|
| State | Accepted |
| Headers | show |
| Series | ipmi: Reduce ipmi_queue_msg_sync() polling loop time to 10ms | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | master/apply_patch Successfully applied |
| snowpatch_ozlabs/snowpatch_job_snowpatch-skiboot | success | Test snowpatch/job/snowpatch-skiboot on branch master |
Stewart Smith <stewart@linux.ibm.com> writes: > On a plain boot, this reduces the time spent in OPAL by ~170ms on > p9dsu. This is due to hiomap (currently) using synchronous IPMI > messages. > > It will also *significantly* reduce latency on runtime flash > operations, as we'll spend typically 10-20ms in OPAL rather than > 100-200ms. It's not an ideal solution to that, but it's a quick > and obvious win for jitter. > > Cc: stable > Signed-off-by: Stewart Smith <stewart@linux.ibm.com> Merged to master as of 28bf1faf44cd6bffcf3df0c00578b279f3faeab1 and should hit 6.0.x as of a41470c9492039947fb6e5ed898017f7deb7bece assuming this in-progress test goes well
diff --git a/core/ipmi.c b/core/ipmi.c index 6fdb9a74b41b..44623a72dbb6 100644 --- a/core/ipmi.c +++ b/core/ipmi.c @@ -179,7 +179,7 @@ void ipmi_queue_msg_sync(struct ipmi_msg *msg) unlock(&sync_lock); while (sync_msg == msg) - time_wait_ms(100); + time_wait_ms(10); } static void ipmi_read_event_complete(struct ipmi_msg *msg)
On a plain boot, this reduces the time spent in OPAL by ~170ms on p9dsu. This is due to hiomap (currently) using synchronous IPMI messages. It will also *significantly* reduce latency on runtime flash operations, as we'll spend typically 10-20ms in OPAL rather than 100-200ms. It's not an ideal solution to that, but it's a quick and obvious win for jitter. Cc: stable Signed-off-by: Stewart Smith <stewart@linux.ibm.com> --- core/ipmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)