On Mon, Aug 03, 2015 at 03:52:21AM -0700, Peter Wemm wrote: > On Monday, August 03, 2015 11:31:58 AM Steven Hartland wrote: > > On 03/08/2015 10:47, Slawa Olhovchenkov wrote: > > > On Mon, Aug 03, 2015 at 09:34:10AM +0000, Steven Hartland wrote: > > >> Author: smh > > >> Date: Mon Aug 3 09:34:09 2015 > > >> New Revision: 286223 > > >> URL: https://svnweb.freebsd.org/changeset/base/286223 > > >> > > >> Log: > > >> Fix KSTACK_PAGES check in ZFS module > > >> > > >> The check introduced by r285946 failed to add the dependency on > > >> opt_kstack_pages.h which meant the default value for the platform > > >> instead > > >> of the customised options KSTACK_PAGES=X was being tested. > > >> > > >> Also wrap in #ifdef __FreeBSD__ for portability. > > > > > > /usr/src/sys/kern/kern_proc.c:int kstack_pages = KSTACK_PAGES; > > > > > > May be check variable kstack_pages is best way? > > > Eliminate dependency on foreign opt_XXXX. > > > > I did think of that but as other modules such as dtrace, which is also > > cddl code, already have this dependency I went with this. > > > > I'm easy though, if there's a concusses that kstack_pages or possibly > > curthread->td_kstack_pages, which would take into account the > > possibility of varied thread stack sizes, then I can make that change. > > > > What do others think? > > The whole thing has missing the point. > > Changing the default for the entire kernel just because the zfs compat > wrappers can't be bothered requesting a suitable value is.. unfortunate.. > particularly when it is in freebsd-provided code, not upstream zfs code. > > Fix the kproc_kthread_add() calls in do_thread_create() and zvol_geom_run() > instead. Enforce a lower bound there for zfs threads instead of making the > entire rest of the kernel use more memory. > > eg: I'm thinking along these lines: > Index: cddl/compat/opensolaris/sys/proc.h > ==================================================== > --- cddl/compat/opensolaris/sys/proc.h (revision 286224) > +++ cddl/compat/opensolaris/sys/proc.h (working copy) > @@ -77,6 +77,8 @@ > ASSERT(state == TS_RUN); > ASSERT(pp == &p0); > > + if (stksize < 16384) > + stksize = 16384; /* Enforce lower bound on ZFS threads */ > error = kproc_kthread_add(proc, arg, &zfsproc, &td, RFSTOPPED, > stksize / PAGE_SIZE, "zfskern", "solthread %p", proc); > if (error == 0) { > > > Beware, some platforms have large pages (eg: ia64 in -stable has 8k, 16k or > 32k pages, from memory). Specifying an arbitrary number of pages in code > that's supposed to be portable isn't a good idea.
This would not help. Issue is the size of the thread0 stack, which overflows in this case. I looked at the possibility of making default kernel stack size configurable by a loader tunable, and the issue is that thread0 gets its stack set up too early (locore for i386, hammer_time() for amd64). I.e., it is possible to make the setting effective for all threads after thread0, but not for the one which causes the issue. I do not want to modify ABI between loader and kernel to pass the parameter. _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
