path: root/cpukit/include/rtems/score/percpu.h
diff options
authorSebastian Huber <>2018-04-28 11:36:11 +0200
committerSebastian Huber <>2019-01-29 13:51:33 +0100
commitdca618404ee61c1be8a883ddb679889dbfea284b (patch)
tree49a61cb40d4fcce31c1c84b7f83737a4852630a0 /cpukit/include/rtems/score/percpu.h
parentf0ae613ba72bc4b95797e2482c4bd0fa5546331d (diff)
Add low level event recording support
Add low level event recording infrastructure for system and user defined events. The infrastructure is able to record high frequency events such as * SMP lock acquire/release, * interrupt entry/exit, * thread switches, * UMA zone allocate/free, and * Ethernet packet input/output, etc. It allows post-mortem analysis in fatal error handlers, e.g. the last events are in the record buffer, the newest event overwrites the oldest event. It is possible to detect record buffer overflows for consumers that expect a continuous stream of events, e.g. to display the system state in real-time. The implementation supports high-end SMP machines (more than 1GHz processor frequency, more than four processors). Add a new API instead. The implementation uses per-processor data structures and no atomic read-modify-write operations. It is uses per-processor ring buffers to record the events. The CPU counter is used to get the time of events. It is combined with periodic uptime events to synchronize it with CLOCK_REALTIME. The existing capture engine tries to solve this problem also, but its performance is not good enough for high-end production systems. The main issues are the variable-size buffers and the use of SMP locks for synchronization. To fix this, the API would change significantly. Update #3665.
Diffstat (limited to 'cpukit/include/rtems/score/percpu.h')
1 files changed, 4 insertions, 0 deletions
diff --git a/cpukit/include/rtems/score/percpu.h b/cpukit/include/rtems/score/percpu.h
index 712d1cde36..22c5c30a00 100644
--- a/cpukit/include/rtems/score/percpu.h
+++ b/cpukit/include/rtems/score/percpu.h
@@ -69,6 +69,8 @@ extern "C" {
#if !defined( ASM )
+struct Record_Control;
struct _Thread_Control;
struct Scheduler_Context;
@@ -513,6 +515,8 @@ typedef struct Per_CPU_Control {
bool boot;
+ struct Record_Control *record;
Per_CPU_Stats Stats;
} Per_CPU_Control;