Hi Steve,
On 10/22/24 10:30, Steven Rostedt wrote:
On Tue, 22 Oct 2024 07:42:10 +0200
Jean-Michel Hautbois <jeanmichel.hautbois@xxxxxxxxxx> wrote:
This part of the patch shouldn't be needed because those shoudl be
called by irq_enter() and irq_exit(). Does this not work if you don't
have these?
Thanks for your quick review !
\o/
Indeed, it works without those lines, so the patch is now a one-liner
:-). I will wait for the second part to be reviewed before sending v2.
I don't know enough about m68k to review that patch. Just incase you
were expecting me to review it.
I was not really expecting you to review the m68k one no :-).
I think I have other issues which might have impact on ftrace too.
For instance, when I launch cyclictest I have a warning about HRTIMERS:
# cyclictest -p 99
WARN: stat /dev/cpu_dma_latency failed: No such file or directory
WARN: High resolution timers not available
policy: fifo: loadavg: 1.21 0.40 0.14 1/122 245
T: 0 ( 245) P:99 I:1000 C: 11203 Min: 92 Act: 623 Avg: 775 Max:
3516
The latencies are quite high...
But regarding ftrace it seems that the trace is not able to give me more
than a microsecond precision. I addded a few trace_printk() in a driver
of mine and I get:
irq/182-dspi-sl-112 [000] D.... 277.160000: dspi_interrupt:
Received 2 bytes
irq/182-dspi-sl-112 [000] D.... 277.160000: dspi_interrupt:
Received 2 bytes
irq/182-dspi-sl-112 [000] D.... 277.163000: dspi_interrupt:
dspi_interrupt
irq/182-dspi-sl-112 [000] D.... 277.163000: dspi_interrupt: TX
FIFO overflow
irq/182-dspi-sl-112 [000] D.... 277.163000: dspi_interrupt:
Restart FIFO
Do you have any clue ?
Thanks !
JM
