summaryrefslogtreecommitdiffstats
path: root/sys/kern/kern_fork.c
Commit message (Collapse)AuthorAgeFilesLines
* MFC r259535:markj2014-03-181-5/+5
| | | | | | | | | | | | | | | | | The fasttrap fork handler is responsible for removing tracepoints in the child process that were inherited from its parent. However, this should not be done in the case of a vfork, since the fork handler ends up removing the tracepoints from the shared vm space, and userland DTrace probes in the parent will no longer fire as a result. Now the child of a vfork may trigger userland DTrace probes enabled in its parent, so modify the fasttrap probe handler to handle this case and handle the child process in the same way that it would handle the traced process. In particular, if once traces function foo() in a process that vforks, and the child calls foo(), fasttrap will treat this call as having come from the parent. This is the behaviour of the upstream code. While here, add #ifdef guards to some code that isn't present upstream.
* MFC r258622: dtrace sdt: remove the ugly sname parameter of SDT_PROBE_DEFINEavg2014-01-171-1/+1
|
* Extend the support for exempting processes from being killed when swap isjhb2013-09-191-0/+6
| | | | | | | | | | | | | | | | | | | | | | exhausted. - Add a new protect(1) command that can be used to set or revoke protection from arbitrary processes. Similar to ktrace it can apply a change to all existing descendants of a process as well as future descendants. - Add a new procctl(2) system call that provides a generic interface for control operations on processes (as opposed to the debugger-specific operations provided by ptrace(2)). procctl(2) uses a combination of idtype_t and an id to identify the set of processes on which to operate similar to wait6(). - Add a PROC_SPROTECT control operation to manage the protection status of a set of processes. MADV_PROTECT still works for backwards compatability. - Add a p_flag2 to struct proc (and a corresponding ki_flag2 to kinfo_proc) the first bit of which is used to track if P_PROTECT should be inherited by new child processes. Reviewed by: kib, jilles (earlier version) Approved by: re (delphij) MFC after: 1 month
* Specify SDT probe argument types in the probe definition itself rather thanmarkj2013-08-151-4/+2
| | | | | | | | | using SDT_PROBE_ARGTYPE(). This will make it easy to extend the SDT(9) API to allow probes with dynamically-translated types. There is no functional change. MFC after: 2 weeks
* Include PID in the error message which is printed when the maxproc limitjh2013-04-191-2/+2
| | | | | | | is exceeded. Improve formatting of the message while here. PR: kern/60550 Submitted by: Lowell Gilbert, bde
* Merge Capsicum overhaul:pjd2013-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Capability is no longer separate descriptor type. Now every descriptor has set of its own capability rights. - The cap_new(2) system call is left, but it is no longer documented and should not be used in new code. - The new syscall cap_rights_limit(2) should be used instead of cap_new(2), which limits capability rights of the given descriptor without creating a new one. - The cap_getrights(2) syscall is renamed to cap_rights_get(2). - If CAP_IOCTL capability right is present we can further reduce allowed ioctls list with the new cap_ioctls_limit(2) syscall. List of allowed ioctls can be retrived with cap_ioctls_get(2) syscall. - If CAP_FCNTL capability right is present we can further reduce fcntls that can be used with the new cap_fcntls_limit(2) syscall and retrive them with cap_fcntls_get(2). - To support ioctl and fcntl white-listing the filedesc structure was heavly modified. - The audit subsystem, kdump and procstat tools were updated to recognize new syscalls. - Capability rights were revised and eventhough I tried hard to provide backward API and ABI compatibility there are some incompatible changes that are described in detail below: CAP_CREATE old behaviour: - Allow for openat(2)+O_CREAT. - Allow for linkat(2). - Allow for symlinkat(2). CAP_CREATE new behaviour: - Allow for openat(2)+O_CREAT. Added CAP_LINKAT: - Allow for linkat(2). ABI: Reuses CAP_RMDIR bit. - Allow to be target for renameat(2). Added CAP_SYMLINKAT: - Allow for symlinkat(2). Removed CAP_DELETE. Old behaviour: - Allow for unlinkat(2) when removing non-directory object. - Allow to be source for renameat(2). Removed CAP_RMDIR. Old behaviour: - Allow for unlinkat(2) when removing directory. Added CAP_RENAMEAT: - Required for source directory for the renameat(2) syscall. Added CAP_UNLINKAT (effectively it replaces CAP_DELETE and CAP_RMDIR): - Allow for unlinkat(2) on any object. - Required if target of renameat(2) exists and will be removed by this call. Removed CAP_MAPEXEC. CAP_MMAP old behaviour: - Allow for mmap(2) with any combination of PROT_NONE, PROT_READ and PROT_WRITE. CAP_MMAP new behaviour: - Allow for mmap(2)+PROT_NONE. Added CAP_MMAP_R: - Allow for mmap(PROT_READ). Added CAP_MMAP_W: - Allow for mmap(PROT_WRITE). Added CAP_MMAP_X: - Allow for mmap(PROT_EXEC). Added CAP_MMAP_RW: - Allow for mmap(PROT_READ | PROT_WRITE). Added CAP_MMAP_RX: - Allow for mmap(PROT_READ | PROT_EXEC). Added CAP_MMAP_WX: - Allow for mmap(PROT_WRITE | PROT_EXEC). Added CAP_MMAP_RWX: - Allow for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). Renamed CAP_MKDIR to CAP_MKDIRAT. Renamed CAP_MKFIFO to CAP_MKFIFOAT. Renamed CAP_MKNODE to CAP_MKNODEAT. CAP_READ old behaviour: - Allow pread(2). - Disallow read(2), readv(2) (if there is no CAP_SEEK). CAP_READ new behaviour: - Allow read(2), readv(2). - Disallow pread(2) (CAP_SEEK was also required). CAP_WRITE old behaviour: - Allow pwrite(2). - Disallow write(2), writev(2) (if there is no CAP_SEEK). CAP_WRITE new behaviour: - Allow write(2), writev(2). - Disallow pwrite(2) (CAP_SEEK was also required). Added convinient defines: #define CAP_PREAD (CAP_SEEK | CAP_READ) #define CAP_PWRITE (CAP_SEEK | CAP_WRITE) #define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ) #define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE) #define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000008ULL) #define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W) #define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X) #define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X) #define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X) #define CAP_RECV CAP_READ #define CAP_SEND CAP_WRITE #define CAP_SOCK_CLIENT \ (CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \ CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN) #define CAP_SOCK_SERVER \ (CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \ CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \ CAP_SETSOCKOPT | CAP_SHUTDOWN) Added defines for backward API compatibility: #define CAP_MAPEXEC CAP_MMAP_X #define CAP_DELETE CAP_UNLINKAT #define CAP_MKDIR CAP_MKDIRAT #define CAP_RMDIR CAP_UNLINKAT #define CAP_MKFIFO CAP_MKFIFOAT #define CAP_MKNOD CAP_MKNODAT #define CAP_SOCK_ALL (CAP_SOCK_CLIENT | CAP_SOCK_SERVER) Sponsored by: The FreeBSD Foundation Reviewed by: Christoph Mallon <christoph.mallon@gmx.de> Many aspects discussed with: rwatson, benl, jonathan ABI compatibility discussed with: kib
* Remove redundant parenthesis.pjd2013-02-171-1/+1
|
* Remove a special case for XEN, which is erronous and makes vfork(2)kib2012-12-151-4/+0
| | | | | | | behaviour to differ from the documented, only on XEN. If there are any issues with XEN pmap left, they should be fixed in pmap. MFC after: 2 weeks
* Fix a race between kern_setitimer() and realitexpire(), where thekib2012-12-041-1/+1
| | | | | | | | | | | | | | | | | | | | | callout is started before kern_setitimer() acquires process mutex, but looses a race and kern_setitimer() gets the process mutex before the callout. Then, assuming that new specified struct itimerval has it_interval zero, but it_value non-zero, the callout, after it starts executing again, clears p->p_realtimer.it_value, but kern_setitimer() already rescheduled the callout. As the result of the race, both p_realtimer is zero, and the callout is rescheduled. Then, in the exit1(), the exit code sees that it_value is zero and does not even try to stop the callout. This allows the struct proc to be reused and eventually the armed callout is re-initialized. The consequence is the corrupted callwheel tailq. Use process mutex to interlock the callout start, which fixes the race. Reported and tested by: pho Reviewed by: jhb MFC after: 2 weeks
* userret() already checks for td_locks when INVARIANTS is enabled, soattilio2012-09-081-1/+0
| | | | | | | there is no need to check if Giant is acquired after it. Reviewed by: kib MFC after: 1 week
* Add a sysctl kern.pid_max, which limits the maximum pid the system iskib2012-08-151-4/+4
| | | | | | | allowed to allocate, and corresponding tunable with the same name. Note that existing processes with higher pids are left intact. MFC after: 1 week
* The falloc() function obtains two references to newly created 'fp'.pjd2012-06-191-2/+6
| | | | | | | | | | | | On success we have to drop one after procdesc_finit() and on failure we have to close allocated slot with fdclose(), which also drops one reference for us and drop the remaining reference with fdrop(). Without this change closing process descriptor didn't result in killing pdfork(2)ed child. Reviewed by: rwatson MFC after: 1 month
* Stop treating td_sigmask specially for the purposes of new threadkib2012-05-261-1/+0
| | | | | | | | | creation. Move it into the copied region of the struct thread. Update some comments. Requested by: bde X-MFC after: never
* Fix panic with RACCT that could occur in low memory (or out of swap)trasz2012-05-221-1/+1
| | | | | | | | situations, due to fork1() calling racct_proc_exit() without calling racct_proc_fork() first. Submitted by: Mateusz Guzik <mjguzik at gmail dot com> (earlier version) Reviewed by: Mateusz Guzik <mjguzik at gmail dot com>
* Currently, the debugger attached to the process executing vfork() doeskib2012-02-271-8/+4
| | | | | | | | | | not get syscall exit notification until the child performed exec of exit. Swap the order of doing ptracestop() and waiting for P_PPWAIT clearing, by postponing the wait into syscallret after ptracestop() notification is done. Reported, tested and reviewed by: Dmitry Mikulin <dmitrym juniper net> MFC after: 2 weeks
* Allow the parent to gather the exit status of the children reparentedkib2012-02-231-0/+1
| | | | | | | | | | to the debugger. When reparenting for debugging, keep the child in the new orphan list of old parent. When looping over the children in kern_wait(), iterate over both children list and orphan list to search for the process by pid. Submitted by: Dmitry Mikulin <dmitrym juniper.net> MFC after: 2 weeks
* Mark the automatically attached child with PL_FLAG_CHILD in structkib2012-02-101-0/+2
| | | | | | | lwpinfo flags, for PT_FOLLOWFORK auto-attachment. In collaboration with: Dmitry Mikulin <dmitrym juniper net> MFC after: 1 week
* Move some code inside the racct_proc_fork(); it spares a few lock operationstrasz2011-10-031-11/+0
| | | | | | and it's more logical this way. MFC after: 3 days
* Fix another bug introduced in r225641, which caused rctl to access certaintrasz2011-10-031-0/+1
| | | | | | fields in 'struct proc' before they got initialized in do_fork(). MFC after: 3 days
* Fix error handling bug that would prevent MAC structures from gettingtrasz2011-09-171-20/+18
| | | | | | freed properly if resource limit got exceeded. Approved by: re (kib)
* Fix long-standing thinko regarding maxproc accounting. Basically,trasz2011-09-171-21/+3
| | | | | | | | | | we were accounting the newly created process to its parent instead of the child itself. This caused problems later, when the child changed its credentials - the per-uid, per-jail etc counters were not properly updated, because the maxproc counter in the child process was 0. Approved by: re (kib)
* In order to maximize the re-usability of kernel code in user space thiskmacy2011-09-161-5/+5
| | | | | | | | | | | | | patch modifies makesyscalls.sh to prefix all of the non-compatibility calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel entry points and all places in the code that use them. It also fixes an additional name space collision between the kernel function psignal and the libc function of the same name by renaming the kernel psignal kern_psignal(). By introducing this change now we will ease future MFCs that change syscalls. Reviewed by: rwatson Approved by: re (bz)
* Add experimental support for process descriptorsjonathan2011-08-181-6/+90
| | | | | | | | | | | | | | | | | | | | | | | | | | A "process descriptor" file descriptor is used to manage processes without using the PID namespace. This is required for Capsicum's Capability Mode, where the PID namespace is unavailable. New system calls pdfork(2) and pdkill(2) offer the functional equivalents of fork(2) and kill(2). pdgetpid(2) allows querying the PID of the remote process for debugging purposes. The currently-unimplemented pdwait(2) will, in the future, allow querying rusage/exit status. In the interim, poll(2) may be used to check (and wait for) process termination. When a process is referenced by a process descriptor, it does not issue SIGCHLD to the parent, making it suitable for use in libraries---a common scenario when using library compartmentalisation from within large applications (such as web browsers). Some observers may note a similarity to Mach task ports; process descriptors provide a subset of this behaviour, but in a UNIX style. This feature is enabled by "options PROCDESC", but as with several other Capsicum kernel features, is not enabled by default in GENERIC 9.0. Reviewed by: jhb, kib Approved by: re (kib), mentor (rwatson) Sponsored by: Google Inc
* Implement an RFTSIGZMB flag to rfork(2) to specify a signal that iskib2011-07-121-1/+16
| | | | | | | | delivered to parent when the child exists. Submitted by: Petr Salinger <Petr.Salinger seznam cz> (Debian/kFreeBSD) MFC after: 1 week X-MFC-note: bump __FreeBSD_version
* All the racct_*() calls need to happen with the proc locked. Fixing thistrasz2011-07-061-0/+6
| | | | | | won't happen before 9.0. This commit adds "#ifdef RACCT" around all the "PROC_LOCK(p); racct_whatever(p, ...); PROC_UNLOCK(p)" instances, in order to avoid useless locking/unlocking in kernels built without "options RACCT".
* Enable accounting for RACCT_NPROC and RACCT_NTHR.trasz2011-03-311-0/+20
| | | | | Sponsored by: The FreeBSD Foundation Reviewed by: kib (earlier version)
* Add racct. It's an API to keep per-process, per-jail, per-loginclasstrasz2011-03-291-0/+17
| | | | | | | | | and per-loginclass resource accounting information, to be used by the new resource limits code. It's connected to the build, but the code that actually calls the new functions will come later. Sponsored by: The FreeBSD Foundation Reviewed by: kib (earlier version)
* Fix some locking nits with the p_state field of struct proc:jhb2011-03-241-7/+4
| | | | | | | | | | | | | | | | | | - Hold the proc lock while changing the state from PRS_NEW to PRS_NORMAL in fork to honor the locking requirements. While here, expand the scope of the PROC_LOCK() on the new process (p2) to avoid some LORs. Previously the code was locking the new child process (p2) after it had locked the parent process (p1). However, when locking two processes, the safe order is to lock the child first, then the parent. - Fix various places that were checking p_state against PRS_NEW without having the process locked to use PROC_LOCK(). Every place was already locking the process, just after the PRS_NEW check. - Remove or reduce the use of PROC_SLOCK() for places that were checking p_state against PRS_NEW. The PROC_LOCK() alone is sufficient for reading the current state. - Reorder fill_kinfo_proc() slightly so it only acquires PROC_SLOCK() once. MFC after: 1 week
* Extend struct sysvec with new method sv_schedtail, which is used for andchagin2011-03-081-1/+3
| | | | | | | | | | | | | | | explicit process at fork trampoline path instead of eventhadler(schedtail) invocation for each child process. Remove eventhandler(schedtail) code and change linux ABI to use newly added sysvec method. While here replace explicit comparing of module sysentvec structure with the newly created process sysentvec to detect the linux ABI. Discussed with: kib MFC after: 2 Week
* Introduce preliminary support of the show description of the ABI ofdchagin2011-02-251-4/+4
| | | | | | | traced process by adding two new events which records value of process sv_flags to the trace file at process creation/execing/exiting time. MFC after: 1 Month.
* Allow debugger to specify that children of the traced process should bekib2011-01-251-10/+63
| | | | | | | | automatically traced. Extend the ptrace(PL_LWPINFO) to report that child just forked. Reviewed by: davidxu, jhb MFC after: 2 weeks
* - Move sched_fork() later in fork() after the various sections of the newjhb2011-01-061-6/+7
| | | | | | | | | | | | | | thread and proc have been copied and zeroed from the old thread and proc. Otherwise attempts to modify thread or process data in sched_fork() could be undone. - Don't copy td_{base,}_user_pri from the old thread to the new thread in sched_fork_thread() in ULE. This is already done courtesy the bcopy() of the thread copy region. - Always initialize the real priority (td_priority) of new threads to the new thread's base priority (td_base_pri) to avoid bogusly inheriting a borrowed priority from the parent thread. MFC after: 2 weeks
* Finishing touches to fork1() - ANSIfy missed function definition, style(9)trasz2011-01-021-27/+20
| | | | | fixes, removal of few comments that didn't really make sense and addition of fork_findpid() locking requirements.
* Refactor fork1() to make it easier to follow. No functional changes.trasz2010-12-101-191/+220
| | | | | Reviewed by: kib (earlier version) Tested by: pho
* MFp4:davidxu2010-12-091-0/+1
| | | | | | | | | It is possible a lower priority thread lending priority to higher priority thread, in old code, it is ignored, however the lending should always be recorded, add field td_lend_user_pri to fix the problem, if a thread does not have borrowed priority, its value is PRI_MAX. MFC after: 1 week
* Add a KASSERT to make it obvious when fork_norfproc() is to be called,trasz2010-12-061-1/+3
| | | | | | | | and set *procp to NULL in all cases. Previously, it was not being set in the ERESTART case. This is effectively no-op, since its value is ignored by callers in the error case. Reviewed by: kib@
* Fix style bug introduced by previous commit.trasz2010-12-061-1/+1
|
* Improve readability by factoring out the !RFPROC case. While here,trasz2010-12-061-59/+57
| | | | | | turn K&R function definitions into ANSI. No functional changes. Reviewed by: kib@
* - When disabling ktracing on a process, free any pending requests thatjhb2010-10-211-15/+1
| | | | | | | | | | | | | | | may be left. This fixes a memory leak that can occur when tracing is disabled on a process via disabling tracing of a specific file (or if an I/O error occurs with the tracefile) if the process's next system call is exit(). The trace disabling code clears p_traceflag, so exit1() doesn't do any KTRACE-related cleanup leading to the leak. I chose to make the free'ing of pending records synchronous rather than patching exit1(). - Move KTRACE-specific logic out of kern_(exec|exit|fork).c and into kern_ktrace.c instead. Make ktrace_mtx private to kern_ktrace.c as a result. MFC after: 1 month
* Create a global thread hash table to speed up thread lookup, usedavidxu2010-10-091-1/+1
| | | | | | | | | | rwlock to protect the table. In old code, thread lookup is done with process lock held, to find a thread, kernel has to iterate through process and thread list, this is quite inefficient. With this change, test shows in extreme case performance is dramatically improved. Earlier patch was reviewed by: jhb, julian
* Fix two bugs in DTrace:rpaulo2010-09-091-9/+15
| | | | | | | * when the process exits, remove the associated USDT probes * when the process forks, duplicate the USDT probes. Sponsored by: The FreeBSD Foundation
* Add an extra comment to the SDT probes definition. This allows us to getrpaulo2010-08-221-1/+1
| | | | | | | | | use '-' in probe names, matching the probe names in Solaris.[1] Add userland SDT probes definitions to sys/sdt.h. Sponsored by: The FreeBSD Foundation Discussed with: rwaston [1]
* Reintroduce the r196640, after fixing the problem with my testing.kib2009-09-011-10/+15
| | | | | | | | | | | | | | | | | | | | | | | | | Remove the altkstacks, instead instantiate threads with kernel stack allocated with the right size from the start. For the thread that has kernel stack cached, verify that requested stack size is equial to the actual, and reallocate the stack if sizes differ [1]. This fixes the bug introduced by r173361 that was committed several days after r173004 and consisted of kthread_add(9) ignoring the non-default kernel stack size. Also, r173361 removed the caching of the kernel stacks for a non-first thread in the process. Introduce separate kernel stack cache that keeps some limited amount of preallocated kernel stacks to lower the latency of thread allocation. Add vm_lowmem handler to prune the cache on low memory condition. This way, system with reasonable amount of the threads get lower latency of thread creation, while still not exhausting significant portion of KVA for unused kstacks. Submitted by: peter [1] Discussed with: jhb, julian, peter Reviewed by: jhb Tested by: pho (and retested according to new test scenarious) MFC after: 1 week
* Reverse r196640 and r196644 for now.kib2009-08-291-15/+10
|
* Dispose the kernel stack of the proper thread.kib2009-08-291-1/+1
| | | | | Submitted by: alc MFC after: 1 week
* Remove the altkstacks, instead instantiate threads with kernel stackkib2009-08-291-10/+15
| | | | | | | | | | | | | | | | | | | | | | | | allocated with the right size from the start. For the thread that has kernel stack cached, verify that requested stack size is equial to the actual, and reallocate the stack if sizes differ [1]. This fixes the bug introduced by r173361 that was committed several days after r173004 and consisted of kthread_add(9) ignoring the non-default kernel stack size. Also, r173361 removed the caching of the kernel stacks for a non-first thread in the process. Introduce separate kernel stack cache that keeps some limited amount of preallocated kernel stacks to lower the latency of thread allocation. Add vm_lowmem handler to prune the cache on low memory condition. This way, system with reasonable amount of the threads get lower latency of thread creation, while still not exhausting significant portion of KVA for unused kstacks. Submitted by: peter [1] Discussed with: jhb, julian, peter Reviewed by: jhb Tested by: pho MFC after: 1 week
* Remove the interim vimage containers, struct vimage and struct procg,jamie2009-07-171-4/+0
| | | | | | and the ioctl-based interface that supported them. Approved by: re (kib), bz (mentor)
* Replace AUDIT_ARG() with variable argument macros with a set more morerwatson2009-06-271-2/+2
| | | | | | | | | | | | | | specific macros for each audit argument type. This makes it easier to follow call-graphs, especially for automated analysis tools (such as fxr). In MFC, we should leave the existing AUDIT_ARG() macros as they may be used by third-party kernel modules. Suggested by: brooks Approved by: re (kib) Obtained from: TrustedBSD Project MFC after: 1 week
* Implement global and per-uid accounting of the anonymous memory. Addkib2009-06-231-2/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved for the uid. The accounting information (charge) is associated with either map entry, or vm object backing the entry, assuming the object is the first one in the shadow chain and entry does not require COW. Charge is moved from entry to object on allocation of the object, e.g. during the mmap, assuming the object is allocated, or on the first page fault on the entry. It moves back to the entry on forks due to COW setup. The per-entry granularity of accounting makes the charge process fair for processes that change uid during lifetime, and decrements charge for proper uid when region is unmapped. The interface of vm_pager_allocate(9) is extended by adding struct ucred *, that is used to charge appropriate uid when allocation if performed by kernel, e.g. md(4). Several syscalls, among them is fork(2), may now return ENOMEM when global or per-uid limits are enforced. In collaboration with: pho Reviewed by: alc Approved by: re (kensmith)
* Adapt vfs kqfilter to the shared vnode lock used by zfs write vop. Usekib2009-06-101-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | vnode interlock to protect the knote fields [1]. The locking assumes that shared vnode lock is held, thus we get exclusive access to knote either by exclusive vnode lock protection, or by shared vnode lock + vnode interlock. Do not use kl_locked() method to assert either lock ownership or the fact that curthread does not own the lock. For shared locks, ownership is not recorded, e.g. VOP_ISLOCKED can return LK_SHARED for the shared lock not owned by curthread, causing false positives in kqueue subsystem assertions about knlist lock. Remove kl_locked method from knlist lock vector, and add two separate assertion methods kl_assert_locked and kl_assert_unlocked, that are supposed to use proper asserts. Change knlist_init accordingly. Add convenience function knlist_init_mtx to reduce number of arguments for typical knlist initialization. Submitted by: jhb [1] Noted by: jhb [2] Reviewed by: jhb Tested by: rnoland
OpenPOWER on IntegriCloud