On 2024/7/5 7:34, Dave Chinner wrote:
On Thu, Jul 04, 2024 at 10:13:22AM -0400, Steven Rostedt wrote:
On Thu, 4 Jul 2024 22:56:29 +1000
Dave Chinner <david@xxxxxxxxxxxxx> wrote:
Having to do this is additional work when writing use-once scripts
that get thrown away when the tracepoint output analysis is done
is painful, and it's completely unnecessary if the tracepoint output
is completely space separated from the start.
If you are using scripts to parse the output, then you could just
enable the "fields" options, which will just ignore the TP_printk() and
print the fields in both their hex and decimal values:
# trace-cmd start -e filemap -O fields
// the above fields change can also be done with:
// echo 1 > /sys/kernel/tracing/options/fields
# trace-cmd show
# tracer: nop
#
# entries-in-buffer/entries-written: 8/8 #P:8
#
# _-----=> irqs-off/BH-disabled
# / _----=> need-resched
# | / _---=> hardirq/softirq
# || / _--=> preempt-depth
# ||| / _-=> migrate-disable
# |||| / delay
# TASK-PID CPU# ||||| TIMESTAMP FUNCTION
# | | | ||||| | |
less-2527 [004] ..... 61949.896458: mm_filemap_add_to_page_cache: pfn=0x144625 (1328677) i_ino=0x335c6 (210374) index=0x0 (0) s_dev=0xfe00003 (266338307) order=(0)
less-2527 [004] d..2. 61949.896926: mm_filemap_delete_from_page_cache: pfn=0x152b07 (1387271) i_ino=0x2d73a (186170) index=0x0 (0) s_dev=0xfe00003 (266338307) order=(0)
jbd2/vda3-8-268 [005] ..... 61954.461964: mm_filemap_add_to_page_cache: pfn=0x152b70 (1387376) i_ino=0xfe00003 (266338307) index=0x30bd33 (3194163) s_dev=0x3 (3) order=(0)
jbd2/vda3-8-268 [005] ..... 61954.462669: mm_filemap_add_to_page_cache: pfn=0x15335b (1389403) i_ino=0xfe00003 (266338307) index=0x30bd40 (3194176) s_dev=0x3 (3) order=(0)
jbd2/vda3-8-268 [005] ..... 62001.565391: mm_filemap_add_to_page_cache: pfn=0x13a996 (1288598) i_ino=0xfe00003 (266338307) index=0x30bd41 (3194177) s_dev=0x3 (3) order=(0)
jbd2/vda3-8-268 [005] ..... 62001.566081: mm_filemap_add_to_page_cache: pfn=0x1446b5 (1328821) i_ino=0xfe00003 (266338307) index=0x30bd43 (3194179) s_dev=0x3 (3) order=(0)
less-2530 [004] ..... 62033.182309: mm_filemap_add_to_page_cache: pfn=0x13d755 (1300309) i_ino=0x2d73a (186170) index=0x0 (0) s_dev=0xfe00003 (266338307) order=(0)
less-2530 [004] d..2. 62033.182801: mm_filemap_delete_from_page_cache: pfn=0x144625 (1328677) i_ino=0x335c6 (210374) index=0x0 (0) s_dev=0xfe00003 (266338307) order=(0)
Yes, I know about that. But this just makes things harder, because
now there are *3* different formats that have to be handled (i.e.
now we also have to strip "()" around numbers).
Perhaps if users want to filter the format, they could enable the
"fields" option in a unified manner. As for TP_printk(), it depends on
how to better display the data used for debugging.
Thanks,
Hongbo
-Dave.
