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Tree: 3e8ed3b93e

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>	6 years ago
Junio C Hamano	0c45d258ec	pack-objects: set number of threads before checking and warning Under NO_PTHREADS build, we warn when delta_search_threads is not set to 1, because that is the only sensible value on a single threaded build. However, the auto detection that kicks in when that variable is set to 0 (e.g. there is no configuration variable or command line option, or an explicit --threads=0 is given from the command line to override the pack.threads configuration to force auto-detection) was not done before the condition to issue this warning was tested. Move the auto-detection code and place it at an appropriate spot. Signed-off-by: Junio C Hamano <gitster@pobox.com>	11 years ago
Junio C Hamano	b361888dd5	thread-utils.h: simplify the inclusion All files that include this header file use the same four line incantation: #ifndef NO_PTHREADS #include <pthread.h> #include "thread-utils.h" #endif Move the responsibility for that gymnastics to the header file from the files that include it. This approach makes it easier to later declare new services that are related to threading in thread-utils.h and have them available to all the threading code. Signed-off-by: Junio C Hamano <gitster@pobox.com>	14 years ago
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>	15 years ago
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>	17 years ago