From: Alexander K. <kri...@fr...> - 2011-11-26 12:51:37
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Sorry, I was not subscribed to the list before, so I am just quoting your previous message from the web archive: >>> ipc(0x1, 0x8001, 0x1, 0, 0x2abe55d4, 0x2aab25e0) = 0 >>> ipc(0x1, 0, 0x1, 0, 0x2abe55c4, 0x2aab25e0) = 0 >>> ipc(0x1, 0x10002, 0x1, 0, 0x2abe55d4, 0x2aab2820) = 0 >>> ipc(0x1, 0, 0x1, 0, 0x2abe55d4, 0x2aab25e0) = 0 >> >> They keep cluttering my strace logs. If I try something like >> strace -e trace='!ipc' -p 17094 -q 2>&1 | grep ipc > ipc.log >> they still occur in the log in the same order of magnitude as >> before. > > This is not the way how it should be. ipc() is not a normal syscall > but a syscall multiplexer which strace is usually capable to decode. > As I said, there is no visible ipc() on x86, x86-64 and arm. > > (...) > > There is something wrong with strace on your platform, otherwise you > would never see this ipc() syscall. I'm not an expert with linux > mips zoo, but it looks like ipc() syscall multiplexer is actually in > use in your system while strace expects separate IPC syscalls. I can > suggest a workaround, but it won't implement proper IPC subcall > decoding on your platform unless somebody with better knowledge about > it will come up with a patch. > > The workaround is to teach strace that ipc() is a IPC syscall: > $ sed -i '/"ipc"/ s/0,/TI,/' linux/mips/syscallent.h > > With this change applied, strace -e trace='!ipc' will hide ipc() syscall. Maybe there is something wrong with strace on my platform, I have no idea and am not the author of the tool. But I can confirm that your latest change http://strace.git.sourceforge.net/git/gitweb.cgi?p=strace/strace;a=commit;h=454dcd458aa0f8ebe6838c1835d779739a9cca77 fixes the problem in my case. May I know if you intend to keep the change in the code base? I mean, is it really just a workaround or does it solve a real problem? I guess it does, because you committed the change for several (all?) platforms. Anyway, thank you for your help, I can filter out ipc() calls now using the "ipc" or "!ipc" category name. :) -- Alexander Kriegisch (kriegaex) http://freetz.org |