January 2009 - Darwin-dev - lists.apple.com

Re: selective disabling of crash reports
by Jean-Daniel Dupas 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Le 18 janv. 09 à 17:09, Jeff Johnson a écrit : Iain, -Jeff On Jan 18, 2009, at 7:07 AM, IainS wrote: Hello, I have read tn2123 and the crash report man page. Does anyone know of a more selective way of dealing with this? tia, Iain _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/devlists%40shadowlab.org This email sent to devlists(a)shadowlab.org _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… It disables the crash windows, not the crash reporter. The Crash Reporter will continue to generate Crash log and to slow down the test. Launch "/Developer/Applications/Utilities/CrashReporterPrefs.app" and select Server. Whilst crash reporter is a very useful and wonderful item - there are certain circumstances in which it can get in the way. In particular, if one is regression-testing on a multi-core machine (i.e. you *expect* a lot of crashes) then there is a problem where the crash report mechanism gives out a "too many crashes" log message and seems to stall for a while. This also sometimes gives false results on the testing (i.e. it seems that an executable has failed by timing out). The latter seems to indicate that I can disable crash reporting "for everything" involving a re-boot (by setting appropriate flags in launchd controls). I'd much prefer to disable the crash reports only for the sessions that are unit testing (since I find that crash reports are generally helpful). Also a re-boot per change is not terribly attractive... This email sent to site_archiver(a)lists.apple.com

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Re: selective disabling of crash reports
by Jeff Johnson 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Iain, -Jeff On Jan 18, 2009, at 7:07 AM, IainS wrote: Hello, I have read tn2123 and the crash report man page. Does anyone know of a more selective way of dealing with this? tia, Iain _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Launch "/Developer/Applications/Utilities/CrashReporterPrefs.app" and select Server. Whilst crash reporter is a very useful and wonderful item - there are certain circumstances in which it can get in the way. In particular, if one is regression-testing on a multi-core machine (i.e. you *expect* a lot of crashes) then there is a problem where the crash report mechanism gives out a "too many crashes" log message and seems to stall for a while. This also sometimes gives false results on the testing (i.e. it seems that an executable has failed by timing out). The latter seems to indicate that I can disable crash reporting "for everything" involving a re-boot (by setting appropriate flags in launchd controls). I'd much prefer to disable the crash reports only for the sessions that are unit testing (since I find that crash reports are generally helpful). Also a re-boot per change is not terribly attractive... This email sent to site_archiver(a)lists.apple.com

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Re: selective disabling of crash reports
by Jean-Daniel Dupas 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… This email sent to site_archiver(a)lists.apple.com

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Re: selective disabling of crash reports
by IainS 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com thanks, Iain _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… On 18 Jan 2009, at 14:38, Joe Ranieri wrote: Does anyone know of a more selective way of dealing with this? On Leopard and later, you can simply install a signal handler for whatever signals you want to trap (just remember to only use signal safe code!). Prior to Leopard, you would need to fiddle with the mach exception port. See <http://lists.apple.com/archives/Cocoa-dev/ 2005/Aug/msg01986.html> for details about the mach exception handling stuff. If I understand correctly - you're suggesting installing a signal handler (as normal) into the code. Unfortunately, that doesn't do what we need in this case: We want the code to abort (it does this intentionally to signify a failure - which is caught by the test-suite) - what I don't want is a crash report - the test framework already knows the code crashed ;-) To split hairs - actually, I wouldn't mind the crash report - the problem is that the mechanism is limiting test throughput - since crash reporter doesn't allow above a certain (unknown) number of crashes per second. When too many crashes per second arrive sometimes this gives a false failure indication (as the executable seems to disappear giving the impression that it timed out). This email sent to site_archiver(a)lists.apple.com

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Re: selective disabling of crash reports
by Joe Ranieri 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com On Jan 18, 2009, at 08:07, IainS wrote: Hello, I have read tn2123 and the crash report man page. -- Joe Ranieri _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Whilst crash reporter is a very useful and wonderful item - there are certain circumstances in which it can get in the way. In particular, if one is regression-testing on a multi-core machine (i.e. you *expect* a lot of crashes) then there is a problem where the crash report mechanism gives out a "too many crashes" log message and seems to stall for a while. This also sometimes gives false results on the testing (i.e. it seems that an executable has failed by timing out). The latter seems to indicate that I can disable crash reporting "for everything" involving a re-boot (by setting appropriate flags in launchd controls). I'd much prefer to disable the crash reports only for the sessions that are unit testing (since I find that crash reports are generally helpful). Also a re-boot per change is not terribly attractive... Does anyone know of a more selective way of dealing with this? On Leopard and later, you can simply install a signal handler for whatever signals you want to trap (just remember to only use signal safe code!). Prior to Leopard, you would need to fiddle with the mach exception port. See <http://lists.apple.com/archives/Cocoa-dev/2005/Aug/msg01986.html > for details about the mach exception handling stuff. This email sent to site_archiver(a)lists.apple.com

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selective disabling of crash reports
by IainS 18 Jan '09

18 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Hello, I have read tn2123 and the crash report man page. Does anyone know of a more selective way of dealing with this? tia, Iain _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Whilst crash reporter is a very useful and wonderful item - there are certain circumstances in which it can get in the way. In particular, if one is regression-testing on a multi-core machine (i.e. you *expect* a lot of crashes) then there is a problem where the crash report mechanism gives out a "too many crashes" log message and seems to stall for a while. This also sometimes gives false results on the testing (i.e. it seems that an executable has failed by timing out). The latter seems to indicate that I can disable crash reporting "for everything" involving a re-boot (by setting appropriate flags in launchd controls). I'd much prefer to disable the crash reports only for the sessions that are unit testing (since I find that crash reports are generally helpful). Also a re-boot per change is not terribly attractive... This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Terry Lambert 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com * Returns: 0 Success * EBADF * EFAULT * fp_lookup:EBADF Bad file descriptor * vnode_getwithref:??? * copyout:EFAULT * vnode_getwithref:??? * vn_stat:??? * soo_stat:??? * pipe_stat:??? * pshm_stat:??? * kqueue_stat:??? - In general, though, its: Also, on the detrace question: -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… On Jan 16, 2009, at 12:37 PM, Joel Reymont wrote: On Jan 16, 2009, at 8:25 PM, Jason Coco wrote: It's a syscall, so it's only a stub in libc. It's actually defined in the kernel (the xnu module). A follow-up question then... under what conditions can fstat return EINVAL (invalid argument)? I can call fstat for stdin, stdout and stderr just fine but as soon as I give it my fd (opened read-only), it gives me an error. I'll go dig through the kernel sources in the meantime. There is a lot of block comment documentation in xnu in bsd/kern/ kern_descrip.c on fstat which tells what error codes can come from where. Unless you are calling this on a weird descriptor, here are the documented returns: The ??? means you're calling it on a weird descriptor, and the code will return whatever it returns as an implementation detail of the descriptor. In general, it means code hat a user might supply or an NKE a user might supply could return a value other than one of the documented error codes here. Typically, this will only happen if someone has written a bogus kernel extention, but, hey, we don't know what code you have loaded into your kernel. Since you came back later and said that the actual call was ftruncate, not fstat, the function you want to look at is actually implemented in xnu in bsd/vfs/vfs_syscalls.c. As I did not need the error codes to change to pass UNIX conformance testing, I didn't not check the origin of the error code and trace them back to their distal causes in the functions called from that function. EINVAL (you told it to truncate to a negative length) fp_lookup:EBADF pshm_truncate:EINVAL (the shared memory segment was already deleted; release your reference, already!) pshm_truncate:EINVAL (the shared memory segment was allocated, but you're failed to initialize it yet) pshm_truncate:EINVAL (mach_make_memory_entry_64 failed, probably because you initialized things wrong) pshm_truncate:ENOMEM (there isn't enough memory; maybe you need to buy more RAM or compile 64 bit?) pshm_truncate:EACCES (it's not mapped for that) EINVAL (you told it to truncate a file type that wasn't a vnode or POSIX shared memory segment) EINVAL (you told it to truncate a vnode, but you didn't open the file for write) vnode_getwithref:EINVAL (the file is not open for write) vnode_getwithref:ENOENT (your node is dead, probably because your FS is corrupted) vnode_setattr:EROFS (you told it to truncate a read-only file; you can't expect to write ROMs) vnode_setattr:??? (whatever the filesystem implementation can return for VNOP_SETATTR; if iit's one of ours, this won't happen) You want to do what's called a speculative function boundary trace, and check the error return on the function you are tracing for EINVAL; if you get an EINVAL, then commit the speculative trace, otherwise, discard it. When you get output for the speculative trace, then it will be the call stack that resulted in the EINVAL being returned. In general, since the error code being returned is not examined/set with an accessor/mutator function, and if it were, the function would most likely be inlined, there's not really a tracepoint for you to trap on in order to trace such things (one of the many reasons programmers should not use data interfaces for important things, and one of the many performance reasons that they do anyway). However, even if you got a trace on the EINVAL set point, that would only give you a proximal cause ("something failed somewhere down the call stack, and that error eventuall bubbled up to here, so I set the BSD error code EINVAL"), so a speculative trace would really be the best way to go in any case. There are a lot of really good examples of how to use this in the Sun DTrace guide. PS: My wild educated guess is you are passing a negative number to the truncate; this will typically happen if you attempt to use something other than an off_t (signed 64 bit) parameter to ftruncate(), and failed to have a prototype in scope at the time you made the call, and then half your 32 bit value happens to be whatever 32 bits of garbage were already in the other register -- you can compile with -Wall - Werror compiler options to catch things like this at compile time. This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Joel Reymont 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=PZUWlr+xhe2wWQq81FVM7nVi5za+Fb3Dfdl/Leoqp1c=; b=Jss/rAuzh9R8c0eTDmJy7r+7AT+g7Tb7zxKkEWtV8mSF5nho22jPE+uJuMGiRme/b9 5MW28zny+LOBxlkKybLMQsJoWJyq95RGhIQ9hAdmxVi1kr+JPmTvP+/9ccIm7hU0yRWj nXCz+GhDjKgvpEevc8xcALrP38vEVRRQO1Nf4= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=TYtAgE9JUY4fWkWZjgaxXQkO0EWv2AKZGXVvU2vneuVbfGF72zp7RiDHNB82hgHY0/ RKagBjDuBUrnxVD3yTFHz1vyiEU7zbkoSO8rFqK+tDgy9y7QNYpjZ1B8oUzsJ491W911 A1eq4asCcryrzyFwPslnVWfd8piRgK95vS1z4= On Jan 16, 2009, at 10:50 PM, Brett George wrote: There's foot in mouth and then there's major foot in mouth. Don't do it if you can help it, or at least invoke it as ./test! --- http://twitter.com/wagerlabs _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Is "fs_usage" any help? Mine is of the latter variety. It goes back to naming your test program... test. Anyway, ftruncate was being called instead of fstat. Back to the drawing board! This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Joel Reymont 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=1xK1uGNAEVf45ONgGMzIMw4ccX/4rucXrS/deWzKPcM=; b=n1cu9KgRPX8rZTkqw5RNv2i2maPl5I4Fm8zTuWAupVmmJFC28YBDk8dbDW94qfrugu UP9AZNVpolWR8NOJb7IU+dVL3wqi4AgfcNmWBm9bNPQ1QVry5e0xXoaZf6DnbvsDAkYl 1UAw6X1IygZ/M11y2CO65XYHFf6jm1pKN/jRg= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=wbms0mWgcBqy20N/OkBvokuoXckNNWVFqalMFOWaWxquQNOClkXgR0mrcUk/zPpkNS /qnZGraGMrtgDBpSFLnL88S/t6xmmPgTu4YPCZxJkvEkhOIGLA473JDKFgB1dULEmSGd jcEo6CvoUsg3u3b1gyopBkMp3dqQj8kI4g5NA= Thanks, Joel On Jan 16, 2009, at 9:12 PM, Kevin Van Vechten wrote: Better yet, use DTrace: #!/usr/sbin/dtrace -s syscall::fstat:return /execname == "myprocess" && arg0 != 0/ { printf("%s[%d] fstat returned %d\n", execname, pid, arg0); ustack(); } --- http://twitter.com/wagerlabs _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Mighty helpful to trace my funcalls, although I still don't know who in the kernel, within the fstat call, sets errno to EINVAL and why. This email sent to site_archiver(a)lists.apple.com

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Re: where is fstat
by Joel Reymont 16 Jan '09

16 Jan '09

site_archiver(a)lists.apple.com Delivered-To: darwin-dev(a)lists.apple.com Dkim-signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:cc:message-id:from:to :in-reply-to:content-type:content-transfer-encoding:mime-version :subject:date:references:x-mailer; bh=OpAD90CymwWW852+YVZy4JgBFWhi+vhuTcmkN1PZb2Q=; b=VKY+552J9tXRiejt6jUq3cZQwHEMP/6HxIwgdAaB8QmtYEhOLXIlBKtiKQkPqIP7u2 HWK1n4EBosfAO26FlC3ULB80pHHDKsp/FghwF9DBpGzIhFUvBrR3AEmVnuZViEUpgZXv 5lfStpf+xo18XwDUFZxz9bN1jy5lKEcYnvGys= Domainkey-signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=cc:message-id:from:to:in-reply-to:content-type :content-transfer-encoding:mime-version:subject:date:references :x-mailer; b=Mxku9OObWo6qhmJCznuQG8n52FjRCwkAtKCqQDrpHPlrAl2GFl8RPiF7fcbymwahwV LAQRE5Ut7nv9LSEFnbrM5E/SQGEXT2QziUuXGWxpFFGlQtW1t3QL2eZ2xUykV1OHgCFT Lm9NtaML5ndBBDYnkm4Y0y4xz+RI/SFIm4ITY= On Jan 16, 2009, at 9:12 PM, Kevin Van Vechten wrote: Kevin, I know what fstat returns, I would like to find out why. How do I use this script? I'm a DTrace newbie! --- http://twitter.com/wagerlabs _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-dev mailing list (Darwin-dev(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-dev/site_archiver%40lists.app… Better yet, use DTrace: This email sent to site_archiver(a)lists.apple.com

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