linux_dsm_epyc7002/kernel/trace
Douglas Anderson 03197fc02b tracing: kdb: Allow ftdump to skip all but the last few entries
The 'ftdump' command in kdb is currently a bit of a last resort, at
least if you have lots of traces turned on.  It's going to print a
whole boatload of data out your serial port which is probably running
at 115200.  This could easily take many, many minutes.

Usually you're most interested in what's at the _end_ of the ftrace
buffer, AKA what happened most recently.  That means you've got to
wait the full time for the dump.  The 'ftdump' command does attempt to
help you a little bit by allowing you to skip a fixed number of
entries.  Unfortunately it provides no way for you to know how many
entries you should skip.

Let's do similar to python and allow you to use a negative number to
indicate that you want to skip all entries except the last few.  This
allows you to quickly see what you want.

Note that we also change the printout in ftdump to print the
(positive) number of entries actually skipped since that could be
helpful to know when you've specified a negative skip count.

Link: http://lkml.kernel.org/r/20190319171206.97107-3-dianders@chromium.org

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-02 21:32:55 -04:00
..
blktrace.c blkcg: annotate implicit fall through 2019-03-13 14:31:12 -06:00
bpf_trace.c Merge branch 'linus' into perf/core, to pick up fixes 2019-02-28 08:27:17 +01:00
fgraph.c tracing: Fix ftrace_graph_get_ret_stack() to use task and not current 2018-12-22 08:21:03 -05:00
ftrace_internal.h ftrace: Create new ftrace_internal.h header 2018-12-08 20:54:06 -05:00
ftrace.c ftrace: Do not process STUB functions in ftrace_ops_list_func() 2019-04-11 11:46:13 -04:00
Kconfig kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig 2019-02-27 21:43:20 +09:00
Makefile tracing: Add unified dynamic event framework 2018-12-08 20:54:09 -05:00
power-traces.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
preemptirq_delay_test.c tracing: Use trace_clock_local() for looping in preemptirq_delay_test.c 2018-10-17 15:35:33 -04:00
ring_buffer_benchmark.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
ring_buffer.c ring-buffer: Fix ring buffer size in rb_write_something() 2019-04-02 18:24:06 -04:00
rpm-traces.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_benchmark.c rcu: Rename cond_resched_rcu_qs() to cond_resched_tasks_rcu_qs() 2018-05-15 10:27:29 -07:00
trace_benchmark.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_branch.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_clock.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
trace_dynevent.c tracing: initialize variable in create_dyn_event() 2019-03-26 08:35:36 -04:00
trace_dynevent.h tracing: Add unified dynamic event framework 2018-12-08 20:54:09 -05:00
trace_entries.h tracing: Change the function format to display function names by perf 2019-02-11 14:53:43 -05:00
trace_event_perf.c tracing/perf: Use strndup_user() instead of buggy open-coded version 2019-02-21 10:35:10 -05:00
trace_events_filter_test.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_events_filter.c tracing: Have the error logs show up in the proper instances 2019-04-08 09:22:44 -04:00
trace_events_hist.c tracing: Have the error logs show up in the proper instances 2019-04-08 09:22:44 -04:00
trace_events_trigger.c tracing: Add trace_array parameter to create_event_filter() 2019-04-08 09:22:28 -04:00
trace_events.c tracing: Kernel access to Ftrace instances 2019-04-02 18:24:06 -04:00
trace_export.c tracing: Add trigger file for trace_markers tracefs/ftrace/print 2018-05-29 08:28:53 -04:00
trace_functions_graph.c tracing: Put a margin between flags and duration for wakeup tracers 2019-02-06 11:56:19 -05:00
trace_functions.c tracing: Update stack trace skipping for ORC unwinder 2018-01-23 15:57:00 -05:00
trace_hwlat.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
trace_irqsoff.c The biggest change for this release is in the histogram code. 2019-03-11 17:01:32 -07:00
trace_kdb.c tracing: kdb: Allow ftdump to skip all but the last few entries 2019-05-02 21:32:55 -04:00
trace_kprobe_selftest.c selftest/ftrace: Move kprobe selftest function to separate compile unit 2018-07-30 18:41:04 -04:00
trace_kprobe_selftest.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_kprobe.c tracing: Use tracing error_log with probe events 2019-04-02 18:24:07 -04:00
trace_mmiotrace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_nop.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_output.c tracing: Simplify printf'ing in seq_print_sym 2018-12-22 08:21:06 -05:00
trace_output.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_preemptirq.c kprobes: Prohibit probing on hardirq tracers 2019-02-13 08:16:40 +01:00
trace_printk.c tracing: Trivia spelling fix containerof() -> container_of() 2018-09-26 12:21:00 +03:00
trace_probe_tmpl.h tracing: probeevent: Correctly update remaining space in dynamic area 2019-02-11 15:58:30 -05:00
trace_probe.c tracing: Have the error logs show up in the proper instances 2019-04-08 09:22:44 -04:00
trace_probe.h tracing: Use tracing error_log with probe events 2019-04-02 18:24:07 -04:00
trace_sched_switch.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_sched_wakeup.c tracing: Add conditional snapshot 2019-02-20 13:51:06 -05:00
trace_selftest_dynamic.c ftrace: Mark function tracer test functions noinline/noclone 2018-01-23 15:57:29 -05:00
trace_selftest.c function_graph: Have selftest also emulate tr->reset() as it did with tr->init() 2019-04-21 19:46:56 -04:00
trace_seq.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
trace_stack.c tracing: Use the return of str_has_prefix() to remove open coded numbers 2018-12-22 22:52:30 -05:00
trace_stat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace_stat.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00
trace_syscalls.c Tracing updates for 4.15: 2017-11-17 14:58:01 -08:00
trace_uprobe.c tracing: Use tracing error_log with probe events 2019-04-02 18:24:07 -04:00
trace.c tracing: Add trace_total_entries() / trace_total_entries_cpu() 2019-05-02 21:32:31 -04:00
trace.h tracing: Add trace_total_entries() / trace_total_entries_cpu() 2019-05-02 21:32:31 -04:00
tracing_map.c tracing: Add SPDX License format tags to tracing files 2018-08-16 19:08:06 -04:00
tracing_map.h tracing: Fix SPDX format headers to use C++ style comments 2018-08-16 19:08:06 -04:00