- fix building for 4.19.312

[packages/lttng-modules.git] / timer_expire_entry.patch

diff --git a/timer_expire_entry.patch b/timer_expire_entry.patch
new file mode 100644 (file)
index 0000000..45794b4
--- /dev/null
+++ b/timer_expire_entry.patch
@@ -0,0 +1,48 @@
+commit b258b549a9bc218a08c102ba54aac2c1d477b45a
+Author: Kienan Stewart <kstewart@efficios.com>
+Date:   Mon Apr 15 09:25:26 2024 -0400
+
+    Fix: timer_expire_entry changed in 4.19.312
+    
+    See upstream commit:
+    
+        commit bbb5b1c060d73ca96ccc8cceaa81f5e1a96e8fa4
+        Author: Anna-Maria Gleixner <anna-maria@linutronix.de>
+        Date:   Thu Mar 21 13:09:21 2019 +0100
+    
+            timer/trace: Improve timer tracing
+    
+            [ Upstream commit f28d3d5346e97e60c81f933ac89ccf015430e5cf ]
+    
+            Timers are added to the timer wheel off by one. This is required in
+            case a timer is queued directly before incrementing jiffies to prevent
+            early timer expiry.
+    
+            When reading a timer trace and relying only on the expiry time of the timer
+            in the timer_start trace point and on the now in the timer_expiry_entry
+            trace point, it seems that the timer fires late. With the current
+            timer_expiry_entry trace point information only now=jiffies is printed but
+            not the value of base->clk. This makes it impossible to draw a conclusion
+            to the index of base->clk and makes it impossible to examine timer problems
+            without additional trace points.
+    
+            Therefore add the base->clk value to the timer_expire_entry trace
+            point, to be able to calculate the index the timer base is located at
+            during collecting expired timers.
+    
+    Change-Id: I2ebdbb637db0966ff51f45bf66916a59a496b50c
+    Signed-off-by: Kienan Stewart <kstewart@efficios.com>
+    Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+
+diff --git a/include/instrumentation/events/timer.h b/include/instrumentation/events/timer.h
+index bd21c037..77c4111a 100644
+--- a/include/instrumentation/events/timer.h
++++ b/include/instrumentation/events/timer.h
+@@ -112,6 +112,7 @@ LTTNG_TRACEPOINT_EVENT(timer_start,
+ #endif
+ 
+ #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,2,0) || \
++      LTTNG_KERNEL_RANGE(4,19,312, 4,20,0) || \
+       LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
+ /**
+  * timer_expire_entry - called immediately before the timer callback