Commit Graph

10 Commits

Author SHA1 Message Date
Pedro Alves
42339bc4e0 Fix build when RUSAGE_THREAD is not available & add warning
Building current GDB on Cygwin, fails like so:

 /home/pedro/gdb/src/gdbsupport/run-time-clock.cc: In function ‘void get_run_time(user_cpu_time_clock::time_point&, system_cpu_time_clock::time_point&, run_time_scope ’:
 /home/pedro/gdb/src/gdbsupport/run-time-clock.cc:52:13: error: ‘RUSAGE_THREAD’ was not declared in this scope; did you mean ‘SIGEV_THREAD’?
    52 |       who = RUSAGE_THREAD;
       |             ^~~~~~~~~~~~~
       |             SIGEV_THREAD

Cygwin does not implement RUSAGE_THREAD.  Googling around, I see
Cygwin is not alone, other platforms don't support it either.  For
example, here is someone suggesting an alternative for darwin/macos:
https://stackoverflow.com/questions/5652463/equivalent-to-rusage-thread-darwin

Fix this by falling back to process scope if thread scope can't be
supported.  I chose this instead of returning zero usage or some other
constant, because if gdb is built without threading support, then
process-scope run time usage is the right info to return.

But instead of falling back silently, print a warning (just once),
like so:

 (gdb) maint set per-command time on
 ⚠️ warning: per-thread run time information not available on this platform

... so that developers on other platforms at least have a hint
upfront.

This new warning also shows on platforms that don't have getrusage in
the first place, but does not show if the build doesn't support
threading at all.

New tests are added to gdb.base/maint.exp, to expect the warning, and
also to ensure other "mt per-command" sub commands don't trigger the
new warning.

Change-Id: Ie01b916b62f87006f855e31594a5ac7cf09e4c02
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Approved-By: Tom Tromey <tom@tromey.com>
2025-05-29 11:08:43 -04:00
Simon Marchi
0b79576c9d gdb: add scoped_time_it
New in v2:

 - actually use m_enabled in the constructor and destructor
 - output using gdb_stdlog->write_async_safe instead of gdb_printf

scoped_time_it is a small utility that measures and prints how much time
a given thread spent in a given scope.  Similar to the time(1) command,
it prints the time spent in user mode, system mode, and the wall clock
time.  It also prints the CPU utilization percentage, which is:

  (user + sys) / wall

This can help spot cases where the workload is not well balanced between
workers, or the CPU utilization is not optimal (perhaps due to
contention around a lock for example).

To use it, just add it in some scope.  For instance, a subsequent patch
adds it here:

      workers.add_task ([this, task_count, iter, last] ()
	{
	  scoped_time_it time_it ("DWARF indexing worker");
	  process_cus (task_count, iter, last);
	});

On destruction, if enabled, it prints a line showing the time spent by
that thread, similar to what time(1) prints.

The example above prints this (one line for each worker thread):

    Time for "DWARF indexing worker": wall 0.173, user 0.120, sys 0.034, user+sys 0.154, 89.0 % CPU
    Time for "DWARF indexing worker": wall 0.211, user 0.144, sys 0.047, user+sys 0.191, 90.5 % CPU
    Time for "DWARF indexing worker": wall 0.368, user 0.295, sys 0.057, user+sys 0.352, 95.7 % CPU
    Time for "DWARF indexing worker": wall 0.445, user 0.361, sys 0.072, user+sys 0.433, 97.3 % CPU
    Time for "DWARF indexing worker": wall 0.592, user 0.459, sys 0.113, user+sys 0.572, 96.6 % CPU
    Time for "DWARF indexing worker": wall 0.739, user 0.608, sys 0.115, user+sys 0.723, 97.8 % CPU
    Time for "DWARF indexing worker": wall 0.831, user 0.677, sys 0.140, user+sys 0.817, 98.3 % CPU
    Time for "DWARF indexing worker": wall 0.949, user 0.789, sys 0.144, user+sys 0.933, 98.3 % CPU

The object is only enabled if per_command_time (controlled by "maint set
per-command time") is true at construction time.  I wanted to avoid
adding a new command for now, but eventually if there are too many
scoped_time_it around the code base and we want to be able to enabled
them selectively (e.g. just the ones in the DWARF reader, or in the
symbol searching functions, etc), we could have a dedicated command for
that.

I added this functionality to GDB because it relies on gdb_printf and
per_command_time, but if we ever need it in gdbsupport, I'm sure we
could find a way to put it there.

Change-Id: I5416ac1448f960f44d85f8449943d994198a271e
Approved-By: Tom Tromey <tom@tromey.com>
2025-04-29 15:10:11 -04:00
Simon Marchi
f7a4e14a0b gdbsupport: move run_time_clock::now(user, system) out of run_time_clock
It is completely unrelated to run_time_clock, so I don't think it makes
sense to have it as a static function there.

Move it to be a free function named "get_run_time".

Change-Id: I0c3e4d3cc44ca37e523c94d72f7cd66add95645e
Approved-By: Tom Tromey <tom@tromey.com>
2025-04-29 15:10:11 -04:00
Tom Tromey
d01e823438 Update copyright dates to include 2025
This updates the copyright headers to include 2025.  I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.

Approved-By: Eli Zaretskii <eliz@gnu.org>
2025-04-08 10:54:39 -06:00
Simon Marchi
18d2988e5d gdb, gdbserver, gdbsupport: remove includes of early headers
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them.  Remove all the inclusions of these files I could find.  Update
the generation scripts where relevant.

Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
2024-03-26 21:13:22 -04:00
Andrew Burgess
1d506c26d9 Update copyright year range in header of all files managed by GDB
This commit is the result of the following actions:

  - Running gdb/copyright.py to update all of the copyright headers to
    include 2024,

  - Manually updating a few files the copyright.py script told me to
    update, these files had copyright headers embedded within the
    file,

  - Regenerating gdbsupport/Makefile.in to refresh it's copyright
    date,

  - Using grep to find other files that still mentioned 2023.  If
    these files were updated last year from 2022 to 2023 then I've
    updated them this year to 2024.

I'm sure I've probably missed some dates.  Feel free to fix them up as
you spot them.
2024-01-12 15:49:57 +00:00
Joel Brobecker
213516ef31 Update copyright year range in header of all files managed by GDB
This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
2023-01-01 17:01:16 +04:00
Joel Brobecker
4a94e36819 Automatic Copyright Year update after running gdb/copyright.py
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.

For the avoidance of doubt, all changes in this commits were
performed by the script.
2022-01-01 19:13:23 +04:00
Joel Brobecker
3666a04883 Update copyright year range in all GDB files
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...

gdb/ChangeLog

        Update copyright year range in copyright header of all GDB files.
2021-01-01 12:12:21 +04:00
Simon Marchi
06b3c5bdb0 gdbsupport: rename source files to .cc
This patch renames the .c source files in gdbsupport to .cc.

In the gdb directory, there is an argument against renaming the source
files, which is that it makes using some git commands more difficult to
do archeology.  Some commands have some kind of "follow" option that
makes git try to follow renames, but it doesn't work in all situations.

Given that we have just moved the gdbsupport directory, that argument
doesn't hold for source files in that directory.  I therefore suggest
renaming them to .cc, so that they are automatically recognized as C++
by various tools and editors.

The original motivation behind this is that when building gdbsupport
with clang, I get:

      CC       agent.o
    clang: error: treating 'c' input as 'c++' when in C++ mode, this behavior is deprecated [-Werror,-Wdeprecated]

In the gdb/ directory, we make clang happy by passing "-x c++".  We
could do this in gdbsupport too, but I think that renaming the files is
a better long-term solution.

gdbserver still does its own build of gdbsupport, so a few changes in
its Makefile are necessary.

gdbsupport/ChangeLog:

	* Makefile.am: Rename source files from .c to .cc.
	(CC, CFLAGS): Don't override.
	(AM_CFLAGS): Rename to ...
	(AM_CXXFLAGS): ... this.
	* Makefile.in: Re-generate.
	* %.c: Rename to %.cc.

gdbserver/ChangeLog:

	* Makefile.in: Rename gdbsupport source files from .c to .cc.
2020-02-13 16:27:03 -05:00