Would it be a bad idea to make the trivial types with sizes less than void pointer lockless in ovs-atomic-pthread just like in gcc4+, at least for x86/64?
Jarno > On Jul 19, 2014, at 10:05 AM, Ben Pfaff <b...@nicira.com> wrote: > > I guess not, I see that xenddk-6.0.0-50762, at least, doesn't have a > libatomic. > >> On Sat, Jul 19, 2014 at 12:04:25AM -0700, Ben Pfaff wrote: >> Does it make a difference if you add -latomic to the linker flags? >> >>> On Fri, Jul 18, 2014 at 05:32:39PM -0700, Jarno Rajahalme wrote: >>> From config.log: >>> >>> configure:13921: checking whether gcc -std=gnu99 supports GCC 4.0+ atomic >>> built-ins >>> configure:13988: gcc -std=gnu99 -o conftest -g -O2 conftest.c -lrt -lm >>> >&5 >>> /tmp/ccZ2M4lr.o: In function `main': >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:57: undefined >>> reference to `__sync_fetch_and_add_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:57: undefined >>> reference to `__sync_fetch_and_sub_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:57: undefined >>> reference to `__sync_fetch_and_or_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:57: undefined >>> reference to `__sync_fetch_and_and_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:57: undefined >>> reference to `__sync_fetch_and_xor_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:58: undefined >>> reference to `__sync_fetch_and_add_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:58: undefined >>> reference to `__sync_fetch_and_sub_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:58: undefined >>> reference to `__sync_fetch_and_or_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:58: undefined >>> reference to `__sync_fetch_and_and_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:58: undefined >>> reference to `__sync_fetch_and_xor_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:59: undefined >>> reference to `__sync_fetch_and_add_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:59: undefined >>> reference to `__sync_fetch_and_sub_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:59: undefined >>> reference to `__sync_fetch_and_or_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:59: undefined >>> reference to `__sync_fetch_and_and_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:59: undefined >>> reference to `__sync_fetch_and_xor_1' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:60: undefined >>> reference to `__sync_fetch_and_add_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:60: undefined >>> reference to `__sync_fetch_and_sub_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:60: undefined >>> reference to `__sync_fetch_and_or_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:60: undefined >>> reference to `__sync_fetch_and_and_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:60: undefined >>> reference to `__sync_fetch_and_xor_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:61: undefined >>> reference to `__sync_fetch_and_add_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:61: undefined >>> reference to `__sync_fetch_and_sub_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:61: undefined >>> reference to `__sync_fetch_and_or_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:61: undefined >>> reference to `__sync_fetch_and_and_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:61: undefined >>> reference to `__sync_fetch_and_xor_2' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:62: undefined >>> reference to `__sync_fetch_and_add_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:62: undefined >>> reference to `__sync_fetch_and_sub_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:62: undefined >>> reference to `__sync_fetch_and_or_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:62: undefined >>> reference to `__sync_fetch_and_and_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:62: undefined >>> reference to `__sync_fetch_and_xor_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:63: undefined >>> reference to `__sync_fetch_and_add_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:63: undefined >>> reference to `__sync_fetch_and_sub_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:63: undefined >>> reference to `__sync_fetch_and_or_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:63: undefined >>> reference to `__sync_fetch_and_and_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:63: undefined >>> reference to `__sync_fetch_and_xor_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:64: undefined >>> reference to `__sync_fetch_and_add_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:64: undefined >>> reference to `__sync_fetch_and_sub_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:64: undefined >>> reference to `__sync_fetch_and_or_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:64: undefined >>> reference to `__sync_fetch_and_and_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:64: undefined >>> reference to `__sync_fetch_and_xor_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:65: undefined >>> reference to `__sync_fetch_and_add_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:65: undefined >>> reference to `__sync_fetch_and_sub_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:65: undefined >>> reference to `__sync_fetch_and_or_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:65: undefined >>> reference to `__sync_fetch_and_and_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:65: undefined >>> reference to `__sync_fetch_and_xor_4' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:66: undefined >>> reference to `__sync_fetch_and_add_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:66: undefined >>> reference to `__sync_fetch_and_sub_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:66: undefined >>> reference to `__sync_fetch_and_or_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:66: undefined >>> reference to `__sync_fetch_and_and_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:66: undefined >>> reference to `__sync_fetch_and_xor_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:67: undefined >>> reference to `__sync_fetch_and_add_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:67: undefined >>> reference to `__sync_fetch_and_sub_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:67: undefined >>> reference to `__sync_fetch_and_or_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:67: undefined >>> reference to `__sync_fetch_and_and_8' >>> /usr/src/redhat/BUILD/openvswitch-2.3.90.37691/conftest.c:67: undefined >>> reference to `__sync_fetch_and_xor_8' >>> collect2: ld returned 1 exit status >>> >>>> On Jul 18, 2014, at 5:00 PM, Jarno Rajahalme <jrajaha...@nicira.com> wrote: >>>> >>>> I think I found the reason for the slowness of cmap on XenServer. >>>> >>>> I was debugging on a XenServer tonight and found out that the configure >>>> test for GCC atomics had apparently failed, as I noticed actual lock and >>>> unlock operations on gdb disassembly, and then by the fact the changes I >>>> made to the ovs-atomic-gcc4+.h did not trigger any recompilations with >>>> ?make? (so there was no dependency on it). >>>> >>>> If the configure check is correct, then there must be something wrong with >>>> the XenServer setup? >>>> >>>> Jarno >>>> >>>>> On Jun 25, 2014, at 11:09 AM, Ben Pfaff <b...@nicira.com> wrote: >>>>> >>>>> I am really surprised to hear that it takes over a minute. On my >>>>> workstation (which is a few years old), "ovstest test-cmap check 1" >>>>> only takes 6.5 seconds. Do you have any idea what's different on >>>>> XenServer? It might be the GCC version, which version is it using? >>>>> >>>>>> On Wed, Jun 25, 2014 at 09:40:12AM -0700, Gurucharan Shetty wrote: >>>>>> I had a quick comment. I noticed while running unit tests on Xenserver >>>>>> that the cuckoo hash unit test was very slow. It takes a little more >>>>>> than one minute to complete. I wonder whether using more cmap would >>>>>> hurt Xenserver's performance? >>>>>> >>>>>>> On Wed, Jun 25, 2014 at 4:19 AM, Jarno Rajahalme >>>>>>> <jrajaha...@nicira.com> wrote: >>>>>>> Ben, >>>>>>> >>>>>>> Thanks for the reviews! >>>>>>> >>>>>>> I have addressed the (minor) comments on the series, will push once the >>>>>>> vector v2 is ack???ed. I???ll keep this last patch as the first in the >>>>>>> classifier RCU series. >>>>>>> >>>>>>> Jarno >>>>>>> >>>>>>>> On Jun 13, 2014, at 10:37 AM, Ben Pfaff <b...@nicira.com> wrote: >>>>>>>> >>>>>>>>> On Mon, Jun 09, 2014 at 11:53:55AM -0700, Jarno Rajahalme wrote: >>>>>>>>> Use cmap instead of hmap & hindex in classifier. Performance impact >>>>>>>>> with current locking strategy is not yet tested. Later patches will >>>>>>>>> introduce RCU into the classifer. >>>>>>>> >>>>>>>> into the "classifier". >>>>>>>> >>>>>>>>> Signed-off-by: Jarno Rajahalme <jrajaha...@nicira.com> >>>>>>>> >>>>>>>> As long as this passes the tests (I assume you ran them) it seems OK >>>>>>>> to me. The tricky review will be when we start actually making the >>>>>>>> classifier RCU. (I don't know if it makes sense to push this patch >>>>>>>> before then. It might be better as the first patch of a series that >>>>>>>> makes the classifier RCU. But I'll leave that decision to you.) >>>>>>>> >>>>>>>> Acked-by: Ben Pfaff <b...@nicira.com> >>>>>>> >>>>>>> _______________________________________________ >>>>>>> dev mailing list >>>>>>> dev@openvswitch.org >>>>>>> http://openvswitch.org/mailman/listinfo/dev >>> _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
