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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-12-15 14:52:16 -0300
commit8d91c1e411f55d7ea91b1183a2e9f8088fb4d5be (patch)
treee9891aa6c295060d065adffd610c4f49ecf884f3 /Documentation/trace
parenta71852147516bc1cb5b0b3cbd13639bfd4022dc8 (diff)
Linux-libre 4.3.2-gnu
Diffstat (limited to 'Documentation/trace')
-rw-r--r--Documentation/trace/coresight.txt4
-rw-r--r--Documentation/trace/ftrace.txt56
2 files changed, 45 insertions, 15 deletions
diff --git a/Documentation/trace/coresight.txt b/Documentation/trace/coresight.txt
index 77d14d51a..0a5c3290e 100644
--- a/Documentation/trace/coresight.txt
+++ b/Documentation/trace/coresight.txt
@@ -15,7 +15,7 @@ HW assisted tracing is becoming increasingly useful when dealing with systems
that have many SoCs and other components like GPU and DMA engines. ARM has
developed a HW assisted tracing solution by means of different components, each
being added to a design at synthesis time to cater to specific tracing needs.
-Compoments are generally categorised as source, link and sinks and are
+Components are generally categorised as source, link and sinks and are
(usually) discovered using the AMBA bus.
"Sources" generate a compressed stream representing the processor instruction
@@ -138,7 +138,7 @@ void coresight_unregister(struct coresight_device *csdev);
The registering function is taking a "struct coresight_device *csdev" and
register the device with the core framework. The unregister function takes
-a reference to a "strut coresight_device", obtained at registration time.
+a reference to a "struct coresight_device", obtained at registration time.
If everything goes well during the registration process the new devices will
show up under /sys/bus/coresight/devices, as showns here for a TC2 platform:
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 7ddb1e319..ef621d34b 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -346,6 +346,11 @@ of ftrace. Here is a list of some of the key files:
x86-tsc: Architectures may define their own clocks. For
example, x86 uses its own TSC cycle clock here.
+ ppc-tb: This uses the powerpc timebase register value.
+ This is in sync across CPUs and can also be used
+ to correlate events across hypervisor/guest if
+ tb_offset is known.
+
To set a clock, simply echo the clock name into this file.
echo global > trace_clock
@@ -686,6 +691,8 @@ The above is mostly meaningful for kernel developers.
The marks are determined by the difference between this
current trace and the next trace.
'$' - greater than 1 second
+ '@' - greater than 100 milisecond
+ '*' - greater than 10 milisecond
'#' - greater than 1000 microsecond
'!' - greater than 100 microsecond
'+' - greater than 10 microsecond
@@ -1939,26 +1946,49 @@ want, depending on your needs.
ie:
- 0) | up_write() {
- 0) 0.646 us | _spin_lock_irqsave();
- 0) 0.684 us | _spin_unlock_irqrestore();
- 0) 3.123 us | }
- 0) 0.548 us | fput();
- 0) + 58.628 us | }
+ 3) # 1837.709 us | } /* __switch_to */
+ 3) | finish_task_switch() {
+ 3) 0.313 us | _raw_spin_unlock_irq();
+ 3) 3.177 us | }
+ 3) # 1889.063 us | } /* __schedule */
+ 3) ! 140.417 us | } /* __schedule */
+ 3) # 2034.948 us | } /* schedule */
+ 3) * 33998.59 us | } /* schedule_preempt_disabled */
[...]
- 0) | putname() {
- 0) | kmem_cache_free() {
- 0) 0.518 us | __phys_addr();
- 0) 1.757 us | }
- 0) 2.861 us | }
- 0) ! 115.305 us | }
- 0) ! 116.402 us | }
+ 1) 0.260 us | msecs_to_jiffies();
+ 1) 0.313 us | __rcu_read_unlock();
+ 1) + 61.770 us | }
+ 1) + 64.479 us | }
+ 1) 0.313 us | rcu_bh_qs();
+ 1) 0.313 us | __local_bh_enable();
+ 1) ! 217.240 us | }
+ 1) 0.365 us | idle_cpu();
+ 1) | rcu_irq_exit() {
+ 1) 0.417 us | rcu_eqs_enter_common.isra.47();
+ 1) 3.125 us | }
+ 1) ! 227.812 us | }
+ 1) ! 457.395 us | }
+ 1) @ 119760.2 us | }
+
+ [...]
+
+ 2) | handle_IPI() {
+ 1) 6.979 us | }
+ 2) 0.417 us | scheduler_ipi();
+ 1) 9.791 us | }
+ 1) + 12.917 us | }
+ 2) 3.490 us | }
+ 1) + 15.729 us | }
+ 1) + 18.542 us | }
+ 2) $ 3594274 us | }
+ means that the function exceeded 10 usecs.
! means that the function exceeded 100 usecs.
# means that the function exceeded 1000 usecs.
+ * means that the function exceeded 10 msecs.
+ @ means that the function exceeded 100 msecs.
$ means that the function exceeded 1 sec.