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)
Just an FYI,
-- Steve
