December 2005 - Darwin-kernel

Re: Threading and Synchronization in Mass storage driver
by Cliff Russell 14 Dec '05

14 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com a_request = new WriteBuffReq[sizeof(WriteBuffReq)]; a_request = new WriteBuffReq; In the first iteration of the loop, the line containing: a_request = objDriver->get_request(request_mutex); On 13-Dec-05, at 5:49 AM, Yogesh P wrote: Hi Herb, As per your suggestion I have tried using IOLockSleep() in my driver code to put the current running thread in wait. But when these API gets called my driver crashes. The Code snippet for the same is as follow: void* com_My_driver::handle_request_loop(void *data) { com_My_driver* objDriver; WriteBuffReq* a_request; /* pointer to a request.*/ a_request = new WriteBuffReq[sizeof(WriteBuffReq)]; request_mutex = IOLockAlloc(); /* lock the mutex, to access the requests list exclusively. */ IOLockLock(request_mutex); /* do forever... */ while (1) { if(num_requests > 0) /* a request is pending */ { a_request = objDriver->get_request(request_mutex); // get the write request node from the linklist objDriver->handle_request(a_request, thread_id); // handle the incoming write request delete[] a_request; /* and lock the mutex again. */ IOLockLock(request_mutex); } /* if(a_request) */ } /* if(num_requests > 0) */ else { /* wait for a request to arrive. note the mutex will be */ /* unlocked here, thus allowing other threads access to */ /* requests list. */ IOLog("handle_request_loop():: thread '%d' before IOLockSleep\n", thread_id); IOLockSleep(request_mutex, (void*) thread_id, 0); // Driver Crashing Here /* and after we return from IOLockSleep, the mutex */ /* is locked again */ } /* else */ } /* while */ } Is that I am doing something wrong in using these API's ?? Looking for your valuable suggestions. Thanks & Regards, Yogesh Pahilwan Have you looked at IOLockSleep()? Same header file as IOLockLock(). Depending on what kind of driver you are implementing you may want to search the docs and the list archives (and developer.apple.com) for "primary interrupt" and "secondary interrupt". Cheers, H. Hi Herb, Sorry Herb. Now I am replying to the old thread. After loading the driver, threads get created successfully and each thread goes in a big while loop and the loop goes on infinitely. Thanks in advance, Yogesh Pahilwan You will find the entire document enlightening actually :-) H. Hi Herb, Thanks for your valuable suggestion about the threading and synchronization in Mac OS X. I am also thankful to Garth for his suggestions. Thanks, Yogesh This email sent to bogvardi(a)gmail.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… At a glance I see several problems in the code that you posted. The line containing: is allocating an *array* of WriteBuffReq objects (with sizeof (WriteBuffReq) objects in the array, in-fact it's actually allocating sizeof(WriteBuffReq) ^ 2 bytes here), is that really what you want? Wouldn't the following be sufficient Is leaking the large array that you previously allocated, probably not what you intended (if the request is coming from get_request you probably don't need to allocate a WriteBuffReq at all). And, I can't see what - if anything request_mutex is actually protecting. If com_My_driver::handle_request_loop is executed on multiple threads, each thread will have it's own request_mutex object - there will be no synchronization between the threads. If com_My_driver::handle_request_loop is run only on a single thread, request_mutex doesn't seem to have an obvious purpose either. Nobody will ever be able to signal request_mutex because it it a stack variable, the IOLockSleep will sleep forever. As for what is crashing - nothing obvious stood out. But, I don't think it really matters at this point as the algorithm is flawed. The real issue is IOKit probably does everything you are trying to recreate, and quite elegantly too. Your time would be best spent figuring out how to build this part of your driver with the already provided IOKit classes. int thread_id = *((int*) data); /* thread identifying number */ if(a_request) /* got a request - handle it and free it */ { IOLockUnlock(request_mutex); On Fri, 2005-12-09 at 00:04, Herb Petschauer wrote: No worries, the less confusion that my addled brain is exposed to, the better... On 08 Dec 2005 18:31:02 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: I am actually implementing a threading and synchronization mechanism for accessing a request queue which is a queue of write data structure having singly linklist. I am creating kernel threads in my init() driver function. These threads access the request queue paralelly by using IOKit's IOLock synchronization primitives. Each thread acquire the lock calling IOLockLock() function and check the request queue whether it is empty or not. If the request queue is empty then the thread release the lock by calling IOLockUnLock() function. So that other threads can access the request queue. Now I have to put each thread on a conditional wait. The conditional wait means that if there is no request in the request queue the thread delays for a nanosecond and release the lock from the request queue for that specified time delay, and as soon as the request comes in the request queue, thread wake ups, acquire the lock and process that specified request. Is there any mechanism in IOKit so that I can put the thread on conditional wait ?? After that condition met, wake up that thread to process the specified request ?? On Wed, 2005-12-07 at 22:01, Herb Petschauer wrote: Again, this email seems to be a new thread. Why not just reply to the old thread? Anway: http://developer.apple.com/documentation/Darwin/ Conceptual/KernelProgramming/services/chapter_16_section_2.html On 07 Dec 2005 18:22:18 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: Now my driver is not getting crash when I call the IOCreateThread() function. Is there any API to put the kernel thread in a wait for a nanosecond in sleep in IOKit?? _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/bogvardi% 40gmail.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/cliff_russell% 40atimi.com This email sent to cliff_russell(a)atimi.com This email sent to site_archiver(a)lists.apple.com

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Re: pthread spinlock calls on mac os 10.3
by Terry Lambert 13 Dec '05

13 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com No. According to POSIX: [SPI] Spin Locks The functionality described is optional. The functionality described is also an extension to the ISO C standard. #endif <http://www.unix.org/version3/inttables.pdf> -- Terry _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… On Dec 13, 2005, at 1:29 AM, Amol Gajewar wrote: Does pthread spinlock calls on mac os 10.3 are available. If your software is capable of using pthread_spin_* style locking, the code should include <unistd.h> and protect itself from using these functions if the value of _POSIX_SPIN_LOCKS is not *at least* 200112L. You can do this at compilation time using the preprocessor by: #include <unistd.h> #if ((_POSIX_SPIN_LOCKS - 200112L) >= 0L) /* it is OK to use functions beginning with the prefix "pthread_spin_" in my program */ #else /* This platform does not support the optional extensions to POSIX and ISO C standards */ You can answer a lot of questions like this for yourself by looking at the contents of <unistd.h> and the contents of this table: The second column, "POSIX Base", indicates 'm' for mandatory, or an option group code (or codes) which must be claimed to be supported by the contents of <unistd.h> before you are permitted to use the APIs safely. As of MacOS 10.4 (or recent XCode releases installed on earlier versions), the contents of <unistd.h> document the manifest constants that guard various APIs, and a comment at the end of the line indicates the option group; so as long as you are looking at a recent version of MacOS X, you will have all the information needed to decide whether or not a given API is supported. If you have to run on 10.3 instead of upgrading, then you need to look at the 10.4 <unistd.h> at the same time, and manually cross-reference to get the option group references for 10.3. Whether they are available for kernel mode or user mode. If they existed, the would only be available for user mode, and with good reason. Locking is actually not a good way to synchronize kernel and user space activity, unless you want you program in user space to be able to make your machine hang for no apparent reason while something in user space blocks the kernel from making progress, and then makes a call that blocks behind the kernel being blocked. There are other mechanisms documented for synchronization between user space daemons and kernel extensions; usually, people use either sockets or Mach messages. Go to <http://www.developer.apple.com> and search for "boundary crossings"; the first document you see will contain the information you need to know in order to implement kernel/user space synchronization. This email sent to site_archiver(a)lists.apple.com

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Re: Threading and Synchronization in Mass storage driver
by Mike Smith 13 Dec '05

13 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com On Dec 13, 2005, at 5:49 AM, Yogesh P wrote: = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… Is that I am doing something wrong in using these API's ?? At the highest level, yes. You're trying to write your own locking architecture, when you should be using the facilities provided by I/O Kit. For example, what you're trying to do here is to re-implement IOCommandPool. Don't do that. This email sent to site_archiver(a)lists.apple.com

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Re: Threading and Synchronization in Mass storage driver
by Yogesh P 13 Dec '05

13 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Hi Herb, As per your suggestion I have tried using IOLockSleep() in my driver code to put the current running thread in wait. But when these API gets called my driver crashes. The Code snippet for the same is as follow: void* com_My_driver::handle_request_loop(void *data) { com_My_driver* objDriver; WriteBuffReq* a_request; /* pointer to a request.*/ a_request = new WriteBuffReq[sizeof(WriteBuffReq)]; int thread_id = *((int*) data); /* thread identifying number */ request_mutex = IOLockAlloc(); /* lock the mutex, to access the requests list exclusively. */ IOLockLock(request_mutex); /* do forever... */ while (1) { if(num_requests > 0) /* a request is pending */ { a_request = objDriver->get_request(request_mutex); // get the write request node from the linklist if(a_request) /* got a request - handle it and free it */ { IOLockUnlock(request_mutex); objDriver->handle_request(a_request, thread_id); // handle the incoming write request delete[] a_request; /* and lock the mutex again. */ IOLockLock(request_mutex); } /* if(a_request) */ } /* if(num_requests > 0) */ else { /* wait for a request to arrive. note the mutex will be */ /* unlocked here, thus allowing other threads access to */ /* requests list. */ IOLog("handle_request_loop():: thread '%d' before IOLockSleep\n", thread_id); IOLockSleep(request_mutex, (void*) thread_id, 0); // Driver Crashing Here /* and after we return from IOLockSleep, the mutex */ /* is locked again */ } /* else */ } /* while */ } Is that I am doing something wrong in using these API's ?? Looking for your valuable suggestions. Thanks & Regards, Yogesh Pahilwan On Fri, 2005-12-09 at 00:04, Herb Petschauer wrote: > No worries, the less confusion that my addled brain is exposed to, the better... > > Have you looked at IOLockSleep()? Same header file as IOLockLock(). > > Depending on what kind of driver you are implementing you may want to > search the docs and the list archives (and developer.apple.com) for > "primary interrupt" and "secondary interrupt". > > Cheers, > H. > > On 08 Dec 2005 18:31:02 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: > > Hi Herb, > > > > Sorry Herb. > > > > Now I am replying to the old thread. > > > > I am actually implementing a threading and synchronization mechanism for > > accessing a request queue which is a queue of write data structure > > having singly linklist. > > > > I am creating kernel threads in my init() driver function. These threads > > access the request queue paralelly by using IOKit's IOLock > > synchronization primitives. > > > > Each thread acquire the lock calling IOLockLock() function and check the > > request queue whether it is empty or not. If the request queue is empty > > then the thread release the lock by calling IOLockUnLock() function. So > > that other threads can access the request queue. > > > > After loading the driver, threads get created successfully and each > > thread goes in a big while loop and the loop goes on infinitely. > > > > Now I have to put each thread on a conditional wait. The conditional > > wait means that if there is no request in the request queue the thread > > delays for a nanosecond and release the lock from the request queue for > > that specified time delay, and as soon as the request comes in the > > request queue, thread wake ups, acquire the lock and process that > > specified request. > > > > Is there any mechanism in IOKit so that I can put the thread on > > conditional wait ?? > > After that condition met, wake up that thread to process the specified > > request ?? > > > > Thanks in advance, > > Yogesh Pahilwan > > > > > > On Wed, 2005-12-07 at 22:01, Herb Petschauer wrote: > > > Again, this email seems to be a new thread. Why not just reply to the > > > old thread? > > > > > > Anway: http://developer.apple.com/documentation/Darwin/Conceptual/KernelProgrammin… > > > > > > You will find the entire document enlightening actually :-) > > > > > > H. > > > > > > On 07 Dec 2005 18:22:18 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: > > > > Hi Herb, > > > > > > > > Thanks for your valuable suggestion about the threading and > > > > synchronization in Mac OS X. > > > > > > > > I am also thankful to Garth for his suggestions. > > > > > > > > > > > > Now my driver is not getting crash when I call the IOCreateThread() > > > > function. > > > > > > > > Is there any API to put the kernel thread in a wait for a nanosecond in > > > > sleep in IOKit?? > > > > > > > > Thanks, > > > > Yogesh > > > > > > > > > > > > > > > > _______________________________________________ > > > > Do not post admin requests to the list. They will be ignored. > > > > Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) > > > > Help/Unsubscribe/Update your Subscription: > > > > http://lists.apple.com/mailman/options/darwin-kernel/bogvardi%40gmail.com > > > > > > > > This email sent to bogvardi(a)gmail.com > > > > > > > > > > _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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pthread spinlock calls on mac os 10.3
by Amol Gajewar 13 Dec '05

13 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Importance: Normal Does pthread spinlock calls on mac os 10.3 are available. Whether they are available for kernel mode or user mode. Amol Gajewar _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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Re: what version of gcc is apple using for it's kernel these days?
by Sam Hart 12 Dec '05

12 Dec '05

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

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Re: KPI, mbuf, strange mbuf and mbuf_len strange definition
by Vincent Lubet 08 Dec '05

08 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Stéphane, On Dec 8, 2005, at 11:25 AM, Stephane Sudre wrote: Could there be a problem with the declaration of mbuf_len? size_t mbuf_len(mbuf_t mbuf); size_t is said to be a __darwin_size_t __darwin_size_t is said to be __SIZE_TYPE__ struct m_hdr { struct mbuf *mh_next; /* next buffer in chain */ struct mbuf *mh_nextpkt; /* next chain in queue/record */ long mh_len; /* amount of data in this mbuf */ so mh_len is signed if I'm not mistaken. p *((struct mbuf *) 0x3d1fd100) $3 = { m_hdr = { mh_next = 0x3d221700, mh_nextpkt = 0x0, mh_len = 0, mh_data = 0x3d1fd13b "@\002\001?\b>\006l!E", mh_type = 0, mh_flags = 0 }, .... p *((struct mbuf *) 0x3d221700) $5 = { m_hdr = { mh_next = 0x3d221600, mh_nextpkt = 0xfffffff7, mh_len = -1, mh_data = 0xffffffff <Address 0xffffffff out of bounds>, mh_type = 0, mh_flags = -1 }, Vincent _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… __SIZE_TYPE__ is said to be long unsigned int (from what I've found with google). The length field should have been unsigned in the first place but that's not how it was in BSD. Because the detail of mbuf structure is now opaque to the KPI, this inconsistency should not be a problem for kernel extensions. My problem is that the m_hdr struct is stating (in the xnu source code): This is a bit "funny" when you're trying to deal with this kind of weird mbuf chain : and you're testing if (mbuf_len( ) < 0) ... Two questions: Why are you testing for a negative size and how did you get this mbuf chain of free mbufs? This email sent to site_archiver(a)lists.apple.com

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Re: KPI, mbuf, strange mbuf and mbuf_len strange definition
by Josh Graessley 08 Dec '05

08 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com -josh On Dec 8, 2005, at 11:25 AM, Stephane Sudre wrote: Could there be a problem with the declaration of mbuf_len? size_t mbuf_len(mbuf_t mbuf); size_t is said to be a __darwin_size_t __darwin_size_t is said to be __SIZE_TYPE__ struct m_hdr { struct mbuf *mh_next; /* next buffer in chain */ struct mbuf *mh_nextpkt; /* next chain in queue/record */ long mh_len; /* amount of data in this mbuf */ so mh_len is signed if I'm not mistaken. p *((struct mbuf *) 0x3d1fd100) $3 = { m_hdr = { mh_next = 0x3d221700, mh_nextpkt = 0x0, mh_len = 0, mh_data = 0x3d1fd13b "@\002\001?\b>\006l!E", mh_type = 0, mh_flags = 0 }, .... p *((struct mbuf *) 0x3d221700) $5 = { m_hdr = { mh_next = 0x3d221600, mh_nextpkt = 0xfffffff7, mh_len = -1, mh_data = 0xffffffff <Address 0xffffffff out of bounds>, mh_type = 0, mh_flags = -1 }, and you're testing if (mbuf_len( ) < 0) ... This email sent to jgraessley(a)apple.com _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com The mismatch could lead to problems, however, an mbuf length of less than zero is invalid. The length is an absolute length. It makes no sense for it to be less than 0. The internal implementation hasn't switched over to an unsigned type yet. It is conceivable that there are bugs with the conversion between the two. In the long run, the length should be unsigned so the KPI is correct. __SIZE_TYPE__ is said to be long unsigned int (from what I've found with google). My problem is that the m_hdr struct is stating (in the xnu source code): This is a bit "funny" when you're trying to deal with this kind of weird mbuf chain : _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/jgraessley% 40apple.com smime.p7s

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KPI, mbuf, strange mbuf and mbuf_len strange definition
by Stephane Sudre 08 Dec '05

08 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Could there be a problem with the declaration of mbuf_len? size_t mbuf_len(mbuf_t mbuf); size_t is said to be a __darwin_size_t __darwin_size_t is said to be __SIZE_TYPE__ My problem is that the m_hdr struct is stating (in the xnu source code): struct m_hdr { struct mbuf *mh_next; /* next buffer in chain */ struct mbuf *mh_nextpkt; /* next chain in queue/record */ long mh_len; /* amount of data in this mbuf */ so mh_len is signed if I'm not mistaken. p *((struct mbuf *) 0x3d1fd100) $3 = { m_hdr = { mh_next = 0x3d221700, mh_nextpkt = 0x0, mh_len = 0, mh_data = 0x3d1fd13b "@\002\001?\b>\006l!E", mh_type = 0, mh_flags = 0 }, .... p *((struct mbuf *) 0x3d221700) $5 = { m_hdr = { mh_next = 0x3d221600, mh_nextpkt = 0xfffffff7, mh_len = -1, mh_data = 0xffffffff <Address 0xffffffff out of bounds>, mh_type = 0, mh_flags = -1 }, and you're testing if (mbuf_len( ) < 0) ... _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… __SIZE_TYPE__ is said to be long unsigned int (from what I've found with google). This is a bit "funny" when you're trying to deal with this kind of weird mbuf chain : This email sent to site_archiver(a)lists.apple.com

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Re: Threading and Synchronization in Mass storage driver
by Herb Petschauer 08 Dec '05

08 Dec '05

site_archiver(a)lists.apple.com Delivered-To: darwin-kernel(a)lists.apple.com Domainkey-signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=nYjl3JKNBym8gjK6oemxCp0H+015FPplu45bx4FxcD5FSOZ3BrVHjXhy1UrAsjR8lx/l4lrpuQDHybw7RQGPC39zxP85fVfOrH08WAYiL+2wQ2c8JDasqWPai/fymhHwID8Lx2KHlNX36zZbsTeSC5Si7ah+r5hzcnUuI64xyz4= No worries, the less confusion that my addled brain is exposed to, the better... Have you looked at IOLockSleep()? Same header file as IOLockLock(). Depending on what kind of driver you are implementing you may want to search the docs and the list archives (and developer.apple.com) for "primary interrupt" and "secondary interrupt". Cheers, H. On 08 Dec 2005 18:31:02 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: > Hi Herb, > > Sorry Herb. > > Now I am replying to the old thread. > > I am actually implementing a threading and synchronization mechanism for > accessing a request queue which is a queue of write data structure > having singly linklist. > > I am creating kernel threads in my init() driver function. These threads > access the request queue paralelly by using IOKit's IOLock > synchronization primitives. > > Each thread acquire the lock calling IOLockLock() function and check the > request queue whether it is empty or not. If the request queue is empty > then the thread release the lock by calling IOLockUnLock() function. So > that other threads can access the request queue. > > After loading the driver, threads get created successfully and each > thread goes in a big while loop and the loop goes on infinitely. > > Now I have to put each thread on a conditional wait. The conditional > wait means that if there is no request in the request queue the thread > delays for a nanosecond and release the lock from the request queue for > that specified time delay, and as soon as the request comes in the > request queue, thread wake ups, acquire the lock and process that > specified request. > > Is there any mechanism in IOKit so that I can put the thread on > conditional wait ?? > After that condition met, wake up that thread to process the specified > request ?? > > Thanks in advance, > Yogesh Pahilwan > > > On Wed, 2005-12-07 at 22:01, Herb Petschauer wrote: > > Again, this email seems to be a new thread. Why not just reply to the > > old thread? > > > > Anway: http://developer.apple.com/documentation/Darwin/Conceptual/KernelProgrammin… > > > > You will find the entire document enlightening actually :-) > > > > H. > > > > On 07 Dec 2005 18:22:18 +0530, Yogesh P <pahilwan.yogesh(a)spsoftindia.com> wrote: > > > Hi Herb, > > > > > > Thanks for your valuable suggestion about the threading and > > > synchronization in Mac OS X. > > > > > > I am also thankful to Garth for his suggestions. > > > > > > > > > Now my driver is not getting crash when I call the IOCreateThread() > > > function. > > > > > > Is there any API to put the kernel thread in a wait for a nanosecond in > > > sleep in IOKit?? > > > > > > Thanks, > > > Yogesh > > > > > > > > > > > > _______________________________________________ > > > Do not post admin requests to the list. They will be ignored. > > > Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) > > > Help/Unsubscribe/Update your Subscription: > > > http://lists.apple.com/mailman/options/darwin-kernel/bogvardi%40gmail.com > > > > > > This email sent to bogvardi(a)gmail.com > > > > > > _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel(a)lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.… This email sent to site_archiver(a)lists.apple.com

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