diff options
| author | Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu> | 2019-10-10 11:50:46 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-17 13:43:55 -0700 |
| commit | 2d058b19b10975054516da34ce225b32598b51e0 (patch) | |
| tree | 3d772af11d20c3d56a8593311c2f01d433efef20 /kernel | |
| parent | 30ec4150a445c29119e9d729beaec74137842512 (diff) | |
tracing/hwlat: Report total time spent in all NMIs during the sample
commit 98dc19c11470ee6048aba723d77079ad2cda8a52 upstream.
nmi_total_ts is supposed to record the total time spent in *all* NMIs
that occur on the given CPU during the (active portion of the)
sampling window. However, the code seems to be overwriting this
variable for each NMI, thereby only recording the time spent in the
most recent NMI. Fix it by accumulating the duration instead.
Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu
Fixes: 7b2c86250122 ("tracing: Add NMI tracing in hwlat detector")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace_hwlat.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c index d7c8e4ec3d9d..b42886167d56 100644 --- a/kernel/trace/trace_hwlat.c +++ b/kernel/trace/trace_hwlat.c @@ -152,7 +152,7 @@ void trace_hwlat_callback(bool enter) if (enter) nmi_ts_start = time_get(); else - nmi_total_ts = time_get() - nmi_ts_start; + nmi_total_ts += time_get() - nmi_ts_start; } if (enter) |