Yes, this is just for debug purposes. I added the code to my module, but it wouldn't compile: # make make -C /lib/modules/2.6.5-1.358/build SUBDIRS=/test/mydriver modules make[1]: Entering directory `/lib/modules/2.6.5-1.358/build' CC [M] /test/mydriver/igg.o /test/mydriver/igg.c: In function `igg_ioctl': /test/mydriver/igg.c:2106: warning: asm operand 1 probably doesn't match constraints /test/mydriver/igg.c:2106: error: impossible constraint in `asm' /test/mydriver/igg.c:2104: warning: `esp' might be used uninitialized in this function make[2]: *** [/test/mydriver/igg.o] Error 1 make[1]: *** [/test/mydriver] Error 2 make[1]: Leaving directory `/lib/modules/2.6.5-1.358/build' make: *** [default] Error 2 # The 2106 lines is the __asm__ line. I see that there are other lines of code like this is the kernel, so I'm stumped as to why this won't compile ? I'm using the kernels Kbuild system so I would have thought that it would have all the right compile flags set. Any help appreciated. Thanks dom -----Original Message----- From: Arjan van de Ven [mailto:arjan@xxxxxxxxxxxxx] Sent: Sunday, February 27, 2005 5:12 AM To: Curran, Dominic Cc: kernelnewbies@xxxxxxxxxxxx Subject: Re: Simple question about getting stack size On Sat, 2005-02-26 at 20:28 -0600, Curran, Dominic wrote: > Hi > > Trying to do something very simple and failing miserably... > > I want to dump out the amount of stack size I have left at different > points in my LKM driver. as a debugging aid I assume > In order to do this I believe I need to know the value of 'current' > and 'esp'. Just copy the following code into yours (your module is gpl so that you can copy such things I assume): 58 #ifdef CONFIG_DEBUG_STACKOVERFLOW 59 /* Debugging check for stack overflow: is there less than 1KB free? */ 60 { 61 long esp; 62 63 __asm__ __volatile__("andl %%esp,%0" : 64 "=r" (esp) : "" (THREAD_SIZE - 1)); 65 if (unlikely(esp < (sizeof(struct thread_info) + STACK_WARN))) { 66 printk("do_IRQ: stack overflow: %ld\n", 67 esp - sizeof(struct thread_info)); 68 dump_stack(); 69 } 70 } 71 #endif -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
