On Mon, 26 Nov 2018 18:01:40, Corinna Vinschen wrote: > > On Nov 23 11:27, James E. King III wrote: [snip]
> > I found that a call to > > clock_gettime(CLOCK_MONOTONIC, ..) has a one-time initialization that > > is not thread-safe. If two threads call this at the same time, they > > will race. The results I am seeing are typically that one of the two > > callers get a timespec structure with zero values, and no error return > > code from the call. > > Thanks for the testcase, but I can't reproduce the problem, neither on > 32 bit nor on 64 bit. I tweaked your makefile to have a 100K loop I > started multiple times with differently optimzed code, but to no avail. > > To account for that, I inspected the code doing the initialization and > found that it uses REALTIME priority when trying to make sure multiple > threads don't collide. This is a bit on the dangerous side, apparently. > > I tweaked the code to use a spinlock instead. > > I'm just about to upload new developer snapshots to > https://cygwin.com/snapshots/ > > Should be up in 10 mins or so. Can you please try if this fixes the > problem for you? - only replaced the cygwin1.dll ... Henri 64-@@ uname -a CYGWIN_NT-6.1 Seven 2.11.3(0.329/5/3) x86_64 Cygwin 64-@@ ls -l /bin/cygwin1* -rwxr-xr-x 1 Henri None 3339661 Nov 8 14:36 /bin/cygwin1-2.11.2.X -rwxr-xr-x 1 Henri None 3337995 Nov 26 18:43 /bin/cygwin1-64-20181126.X -rwxr-xr-x 1 Henri None 3337995 Nov 26 18:43 /bin/cygwin1.dll 64-@@ cd threads 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ make test 64-@@ vi Makefile 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ #... wait a while ... 64-@@ for loop in {1..100}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..1000}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..1000}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..1000}; do ./cyg_hires_clock_race.exe; done 64-@@ for loop in {1..10000}; do ./cyg_hires_clock_race.exe; done 64-@@# That is enough! ===== -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
