Commit Graph

7 Commits

Author SHA1 Message Date
Nguyễn Thái Ngọc Duy
0ec79358d0 thread-utils: macros to unconditionally compile pthreads API
When built with NO_PTHREADS, the macros are used make the code build
even though pthreads header and library may be missing. The code can
still have different code paths for no threads support with
HAVE_THREADS variable.

There are of course impacts on no-pthreads builds:

- data structure may get slightly bigger because all the mutexes and
  pthread_t are present (as an int)

- code execution is not impacted much. Locking (in hot path) is
  no-op. Other wrapper function calls really should not matter much.

- the binary size grows bigger because of threaded code. But at least
  on Linux this does not matter, if some code is not executed, it's
  not mapped in memory.

This is a preparation step to remove "#ifdef NO_PTHREADS" in the code
mostly because of maintainability. As Jeff put it

> it's probably OK to stop thinking of it as "non-threaded platforms
> are the default and must pay zero cost" and more as "threaded
> platforms are the default, and non-threaded ones are OK to pay a
> small cost as long as they still work".

Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-10-29 11:22:48 +09:00
Kyle J. McKay
a25b5a32c7 thread-utils.c: detect CPU count on older BSD-like systems
Not all systems support using sysconf to detect the number
of available CPU cores.  Older BSD and BSD-derived systems
only provide the information via the sysctl function.

If HAVE_BSD_SYSCTL is defined attempt to retrieve the number
of available CPU cores using the sysctl function.

If HAVE_BSD_SYSCTL is not defined or the sysctl function
fails, we still attempt to get the information via sysconf.

Signed-off-by: Kyle J. McKay <mackyle@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-03-10 15:13:28 -07:00
Jonathan Nieder
380395d094 mingw: rename WIN32 cpp macro to GIT_WINDOWS_NATIVE
Throughout git, it is assumed that the WIN32 preprocessor symbol is
defined on native Windows setups (mingw and msvc) and not on Cygwin.
On Cygwin, most of the time git can pretend this is just another Unix
machine, and Windows-specific magic is generally counterproductive.

Unfortunately Cygwin *does* define the WIN32 symbol in some headers.
Best to rely on a new git-specific symbol GIT_WINDOWS_NATIVE instead,
defined as follows:

	#if defined(WIN32) && !defined(__CYGWIN__)
	# define GIT_WINDOWS_NATIVE
	#endif

After this change, it should be possible to drop the
CYGWIN_V15_WIN32API setting without any negative effect.

[rj: %s/WINDOWS_NATIVE/GIT_WINDOWS_NATIVE/g ]

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-08 12:14:35 -07:00
Stephen Boyd
c2e86addb8 Fix sparse warnings
Fix warnings from 'make check'.

 - These files don't include 'builtin.h' causing sparse to complain that
   cmd_* isn't declared:

   builtin/clone.c:364, builtin/fetch-pack.c:797,
   builtin/fmt-merge-msg.c:34, builtin/hash-object.c:78,
   builtin/merge-index.c:69, builtin/merge-recursive.c:22
   builtin/merge-tree.c:341, builtin/mktag.c:156, builtin/notes.c:426
   builtin/notes.c:822, builtin/pack-redundant.c:596,
   builtin/pack-refs.c:10, builtin/patch-id.c:60, builtin/patch-id.c:149,
   builtin/remote.c:1512, builtin/remote-ext.c:240,
   builtin/remote-fd.c:53, builtin/reset.c:236, builtin/send-pack.c:384,
   builtin/unpack-file.c:25, builtin/var.c:75

 - These files have symbols which should be marked static since they're
   only file scope:

   submodule.c:12, diff.c:631, replace_object.c:92, submodule.c:13,
   submodule.c:14, trace.c:78, transport.c:195, transport-helper.c:79,
   unpack-trees.c:19, url.c:3, url.c:18, url.c:104, url.c:117, url.c:123,
   url.c:129, url.c:136, thread-utils.c:21, thread-utils.c:48

 - These files redeclare symbols to be different types:

   builtin/index-pack.c:210, parse-options.c:564, parse-options.c:571,
   usage.c:49, usage.c:58, usage.c:63, usage.c:72

 - These files use a literal integer 0 when they really should use a NULL
   pointer:

   daemon.c:663, fast-import.c:2942, imap-send.c:1072, notes-merge.c:362

While we're in the area, clean up some unused #includes in builtin files
(mostly exec_cmd.h).

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-22 10:16:54 -07:00
Johannes Sixt
9374919442 Thread-safe xmalloc and xrealloc needs a recursive mutex
The mutex used to protect object access (read_mutex) may need to be
acquired recursively.  Introduce init_recursive_mutex() helper function
in thread-utils.c that constructs a mutex with the PHREAD_MUTEX_RECURSIVE
attribute.

pthread_mutex_init() emulation on Win32 is already recursive as it is
implemented on top of the CRITICAL_SECTION type, which is recursive.

    http://msdn.microsoft.com/en-us/library/ms682530%28VS.85%29.aspx

Add do-nothing compatibility wrappers for pthread_mutexattr* functions.

Initial-version-by: Fredrik Kuivinen <frekui@gmail.com>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-08 23:06:39 -07:00
Marius Storm-Olsen
435bdf8c7f Make usage of windows.h lean and mean
Centralize the include of windows.h in git-compat-util.h, turn on
WIN32_LEAN_AND_MEAN to avoid including plenty of other header files
which is not needed in Git. Also ensure we load winsock2.h first,
so we don't load the older winsock definitions at a later stage,
since they contain duplicate definitions.

When moving windows.h into git-compat-util.h, we need to protect
the definition of struct pollfd in mingw.h, since this file is used
by both MinGW and MSVC, and the latter defines this struct in
winsock2.h.

We need to keep the windows.h include in compat/win32.h, since its
shared by both MinGW and Cygwin, and we're not touching Cygwin in
this commit. The include in git-compat-util.h is protected with an
ifdef WIN32, which is not the case when compiling for Cygwin.

Signed-off-by: Marius Storm-Olsen <mstormo@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-09-18 20:00:42 -07:00
Andreas Ericsson
833e3df171 pack-objects: Add runtime detection of online CPU's
Packing objects can be done in parallell nowadays, but it's
only done if the config option pack.threads is set to a value
above 1. Because of that, the code-path used is often not the
most optimal one.

This patch adds a routine to detect the number of online CPU's
at runtime (online_cpus()). When pack.threads (or --threads=) is
given a value of 0, the number of threads is set to the number of
online CPU's. This feature is also documented.

As per Nicolas Pitre's recommendations, the default is still to
run pack-objects single-threaded unless explicitly activated,
either by configuration or by command line parameter.

The routine online_cpus() is a rework of "numcpus.c", written by
one Philip Willoughby <pgw99@doc.ic.ac.uk>. numcpus.c is in the
public domain and can presently be downloaded from
http://csgsoft.doc.ic.ac.uk/numcpus/

Signed-off-by: Andreas Ericsson <ae@op5.se>
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-02-23 12:00:32 -08:00