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* Fix ia64 to not override the call stack bottom address with thekib2015-08-031-2/+1
| | | | | | | | | register stack bottom address, after the merge of r284956 in r285967. Note: this is a direct commit to stable/10. Reported and tested by: clusteradm (peter) Sponsored by: The FreeBSD Foundation
* MFC r284956:kib2015-07-281-1/+1
| | | | Do not calculate the stack's bottom address twice.
* MFC r282708:kib2015-05-241-47/+58
| | | | | On exec, single-threading must be enforced before arguments space is allocated from exec_map.
* MFC r272290 (by mjg):kib2015-04-271-22/+1
| | | | Use bzero instead of explicitly zeroing stuff in do_execve.
* MFC r281883:kib2015-04-251-1/+1
| | | | | Handle incorrect ELF images specifying size for PT_GNU_STACK not being multiple of page size.
* MFC r281548:kib2015-04-221-2/+15
| | | | | Implement support for binary to request specific stack size for the initial thread.
* Merge r263233 from HEAD to stable/10:rwatson2015-03-191-2/+2
| | | | | | | | | Update kernel inclusions of capability.h to use capsicum.h instead; some further refinement is required as some device drivers intended to be portable over FreeBSD versions rely on __FreeBSD_version to decide whether to include capability.h. Sponsored by: Google, Inc.
* MFC r277322:kib2015-01-251-0/+2
| | | | | Add procctl(2) PROC_TRACE_CTL command to enable or disable debugger attachment to the process.
* MFC r275745:kib2014-12-271-3/+3
| | | | | | | | | | Add facility to stop all userspace processes. MFC r275753: Fix gcc build. MFC r275820: Add missed break.
* Merge the fueword(9) and casueword(9). In particular,kib2014-11-181-9/+17
| | | | | | | | | | | | | | | | | | | | | | | MFC r273783: Add fueword(9) and casueword(9) functions. MFC note: ia64 is handled like arm, with NO_FUEWORD define. MFC r273784: Replace some calls to fuword() by fueword() with proper error checking. MFC r273785: Convert kern_umtx.c to use fueword() and casueword(). MFC note: the sys__umtx_lock and sys__umtx_unlock syscalls are not converted, they are removed from HEAD, and not used. The do_sem2*() family is not yet merged to stable/10, corresponding chunk will be merged after do_sem2* are committed. MFC r273788 (by jkim): Actually install casuword(9) to fix build. MFC r273911: Add type qualifier volatile to the base (userspace) address argument of fuword(9) and suword(9).
* MFC r269907:kib2014-08-201-0/+1
| | | | Fix leaks of unqueued unwired pages.
* MFC r268636:mjg2014-08-171-1/+1
| | | | Plug p_pptr null test in do_execve. It is always true.
* MFC r268365:mjg2014-08-171-2/+4
| | | | | | | | Don't call crdup nor uifind under vnode lock. A locked vnode can get into the way of satisyfing malloc with M_WATOK. This is a fixup to r268087.
* MFC r268136:mjg2014-08-171-1/+3
| | | | Plug gcc warning after r268074 about unitialized newsigacts
* MFC r268087:mjg2014-08-171-10/+10
| | | | Don't call crcopysafe or uifind unnecessarily in execve.
* MFC r268074:mjg2014-08-171-5/+4
| | | | | | | | | | Perform a lockless check in sigacts_shared. It is used only during execve (i.e. singlethreaded), so there is no fear of returning 'not shared' which soon becomes 'shared'. While here reorganize the code a little to avoid proc lock/unlock in shared case.
* MFC r268002:mjg2014-07-061-2/+2
| | | | | | Call fdcloseexec right after fdunshare. No functional changes.
* MFC r268001:mjg2014-07-061-1/+1
| | | | | | | Make fdunshare accept only td parameter. Proc had to match the thread anyway and 2 parameters were inconsistent with the rest.
* MFC r266464:kib2014-05-231-0/+9
| | | | | In execve(2), postpone the free of old vmspace until the threads are resumed and exited.
* MFC r263349:kib2014-03-261-21/+24
| | | | Make the array pointed to by AT_PAGESIZES auxv properly aligned.
* MFC r258622: dtrace sdt: remove the ugly sname parameter of SDT_PROBE_DEFINEavg2014-01-171-5/+5
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* MFC r256504:kib2013-10-251-0/+14
| | | | | | | | Add a sysctl kern.disallow_high_osrel which disables executing the images compiled on the world with higher major version number than the high version number of the booted kernel. Default to disable. Approved by: re (glebius)
* Change the cap_rights_t type from uint64_t to a structure that we can extendpjd2013-09-051-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | in the future in a backward compatible (API and ABI) way. The cap_rights_t represents capability rights. We used to use one bit to represent one right, but we are running out of spare bits. Currently the new structure provides place for 114 rights (so 50 more than the previous cap_rights_t), but it is possible to grow the structure to hold at least 285 rights, although we can make it even larger if 285 rights won't be enough. The structure definition looks like this: struct cap_rights { uint64_t cr_rights[CAP_RIGHTS_VERSION + 2]; }; The initial CAP_RIGHTS_VERSION is 0. The top two bits in the first element of the cr_rights[] array contain total number of elements in the array - 2. This means if those two bits are equal to 0, we have 2 array elements. The top two bits in all remaining array elements should be 0. The next five bits in all array elements contain array index. Only one bit is used and bit position in this five-bits range defines array index. This means there can be at most five array elements in the future. To define new right the CAPRIGHT() macro must be used. The macro takes two arguments - an array index and a bit to set, eg. #define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL) We still support aliases that combine few rights, but the rights have to belong to the same array element, eg: #define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL) #define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL) #define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP) There is new API to manage the new cap_rights_t structure: cap_rights_t *cap_rights_init(cap_rights_t *rights, ...); void cap_rights_set(cap_rights_t *rights, ...); void cap_rights_clear(cap_rights_t *rights, ...); bool cap_rights_is_set(const cap_rights_t *rights, ...); bool cap_rights_is_valid(const cap_rights_t *rights); void cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src); void cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src); bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little); Capability rights to the cap_rights_init(), cap_rights_set(), cap_rights_clear() and cap_rights_is_set() functions are provided by separating them with commas, eg: cap_rights_t rights; cap_rights_init(&rights, CAP_READ, CAP_WRITE, CAP_FSTAT); There is no need to terminate the list of rights, as those functions are actually macros that take care of the termination, eg: #define cap_rights_set(rights, ...) \ __cap_rights_set((rights), __VA_ARGS__, 0ULL) void __cap_rights_set(cap_rights_t *rights, ...); Thanks to using one bit as an array index we can assert in those functions that there are no two rights belonging to different array elements provided together. For example this is illegal and will be detected, because CAP_LOOKUP belongs to element 0 and CAP_PDKILL to element 1: cap_rights_init(&rights, CAP_LOOKUP | CAP_PDKILL); Providing several rights that belongs to the same array's element this way is correct, but is not advised. It should only be used for aliases definition. This commit also breaks compatibility with some existing Capsicum system calls, but I see no other way to do that. This should be fine as Capsicum is still experimental and this change is not going to 9.x. Sponsored by: The FreeBSD Foundation
* Remove the deprecated VM_ALLOC_RETRY flag for the vm_page_grab(9).kib2013-08-221-1/+1
| | | | | | | | The flag was mandatory since r209792, where vm_page_grab(9) was changed to only support the alloc retry semantic. Suggested and reviewed by: alc Sponsored by: The FreeBSD Foundation
* Specify SDT probe argument types in the probe definition itself rather thanmarkj2013-08-151-6/+3
| | | | | | | | | 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
* The soft and hard busy mechanism rely on the vm object lock to work.attilio2013-08-091-6/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unify the 2 concept into a real, minimal, sxlock where the shared acquisition represent the soft busy and the exclusive acquisition represent the hard busy. The old VPO_WANTED mechanism becames the hard-path for this new lock and it becomes per-page rather than per-object. The vm_object lock becames an interlock for this functionality: it can be held in both read or write mode. However, if the vm_object lock is held in read mode while acquiring or releasing the busy state, the thread owner cannot make any assumption on the busy state unless it is also busying it. Also: - Add a new flag to directly shared busy pages while vm_page_alloc and vm_page_grab are being executed. This will be very helpful once these functions happen under a read object lock. - Move the swapping sleep into its own per-object flag The KPI is heavilly changed this is why the version is bumped. It is very likely that some VM ports users will need to change their own code. Sponsored by: EMC / Isilon storage division Discussed with: alc Reviewed by: jeff, kib Tested by: gavin, bapt (older version) Tested by: pho, scottl
* Replace kernel virtual address space allocation with vmem. This providesjeff2013-08-071-2/+2
| | | | | | | | | | | | | transparent layering and better fragmentation. - Normalize functions that allocate memory to use kmem_* - Those that allocate address space are named kva_* - Those that operate on maps are named kmap_* - Implement recursive allocation handling for kmem_arena in vmem. Reviewed by: alc Tested by: pho Sponsored by: EMC / Isilon Storage Division
* Revert r253939:attilio2013-08-051-2/+2
| | | | | | | | | | | | | We cannot busy a page before doing pagefaults. Infact, it can deadlock against vnode lock, as it tries to vget(). Other functions, right now, have an opposite lock ordering, like vm_object_sync(), which acquires the vnode lock first and then sleeps on the busy mechanism. Before this patch is reinserted we need to break this ordering. Sponsored by: EMC / Isilon storage division Reported by: kib
* The page hold mechanism is fast but it has couple of fallouts:attilio2013-08-041-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | - It does not let pages respect the LRU policy - It bloats the active/inactive queues of few pages Try to avoid it as much as possible with the long-term target to completely remove it. Use the soft-busy mechanism to protect page content accesses during short-term operations (like uiomove_fromphys()). After this change only vm_fault_quick_hold_pages() is still using the hold mechanism for page content access. There is an additional complexity there as the quick path cannot immediately access the page object to busy the page and the slow path cannot however busy more than one page a time (to avoid deadlocks). Fixing such primitive can bring to complete removal of the page hold mechanism. Sponsored by: EMC / Isilon storage division Discussed with: alc Reviewed by: jeff Tested by: pho
* Don't busy the page unless we are likely to release the object lock.alc2013-06-061-2/+4
| | | | | Reviewed by: kib Sponsored by: EMC / Isilon Storage Division
* Do not map the shared page COW. If the process wired its addresskib2013-06-031-2/+3
| | | | | | | | | | | | | space, fork(2) would cause shadowing of the physical object and copying of the shared page into private copy, effectively preventing updates for the exported timehands structure and stopping the clock. Specify the maximum allowed permissions for the page to be read and execute, preventing write from the user mode. Reported and tested by: <huanghwh@yahoo.com> Sponsored by: The FreeBSD Foundation MFC after: 2 weeks
* MFCattilio2013-03-021-3/+0
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| * Merge Capsicum overhaul:pjd2013-03-021-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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
* | Rename VM_OBJECT_LOCK(), VM_OBJECT_UNLOCK() and VM_OBJECT_TRYLOCK() toattilio2013-02-201-3/+3
| | | | | | | | | | | | their "write" versions. Sponsored by: EMC / Isilon storage division
* | Switch vm_object lock to be a rwlock.attilio2013-02-201-0/+1
|/ | | | | | | | * VM_OBJECT_LOCK and VM_OBJECT_UNLOCK are mapped to write operations * VM_OBJECT_SLEEP() is introduced as a general purpose primitve to get a sleep operation using a VM_OBJECT_LOCK() as protection * The approach must bear with vm_pager.h namespace pollution so many files require including directly rwlock.h
* When vforked child is traced, the debugging events are not generatedkib2013-02-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | until child performs exec(). The behaviour is reasonable when a debugger is the real parent, because the parent is stopped until exec(), and sending a debugging event to the debugger would deadlock both parent and child. On the other hand, when debugger is not the parent of the vforked child, not sending debugging signals makes it impossible to debug across vfork. Fix the issue by declining generating debug signals only when vfork() was done and child called ptrace(PT_TRACEME). Set a new process flag P_PPTRACE from the attach code for PT_TRACEME, if P_PPWAIT flag is set, which indicates that the process was created with vfork() and still did not execed. Check P_PPTRACE from issignal(), instead of refusing the trace outright for the P_PPWAIT case. The scope of P_PPTRACE is exactly contained in the scope of P_PPWAIT. Found and tested by: zont Reviewed by: pluknet MFC after: 2 weeks
* The r241025 fixed the case when a binary, executed from nullfs mount,kib2012-11-021-2/+5
| | | | | | | | | | | | | | | | | | | | | | | was still possible to open for write from the lower filesystem. There is a symmetric situation where the binary could already has file descriptors opened for write, but it can be executed from the nullfs overlay. Handle the issue by passing one v_writecount reference to the lower vnode if nullfs vnode has non-zero v_writecount. Note that only one write reference can be donated, since nullfs only keeps one use reference on the lower vnode. Always use the lower vnode v_writecount for the checks. Introduce the VOP_GET_WRITECOUNT to read v_writecount, which is currently always bypassed to the lower vnode, and VOP_ADD_WRITECOUNT to manipulate the v_writecount value, which manages a single bypass reference to the lower vnode. Caling the VOPs instead of directly accessing v_writecount provide the fix described in the previous paragraph. Tested by: pho MFC after: 3 weeks
* Remove the support for using non-mpsafe filesystem modules.kib2012-10-221-21/+4
| | | | | | | | | | | | In particular, do not lock Giant conditionally when calling into the filesystem module, remove the VFS_LOCK_GIANT() and related macros. Stop handling buffers belonging to non-mpsafe filesystems. The VFS_VERSION is bumped to indicate the interface change which does not result in the interface signatures changes. Conducted and reviewed by: attilio Tested by: pho
* ktrace/kern_exec: check p_tracecred instead of p_credavg2012-10-061-1/+2
| | | | | | | | | .. when deciding whether to continue tracing across suid/sgid exec. Otherwise if root ktrace-d an unprivileged process and the processed exec-ed a suid program, then tracing didn't continue across exec. Reviewed by: bde, kib MFC after: 22 days
* Fix the mis-handling of the VV_TEXT on the nullfs vnodes.kib2012-09-281-8/+5
| | | | | | | | | | | | | | | | If you have a binary on a filesystem which is also mounted over by nullfs, you could execute the binary from the lower filesystem, or from the nullfs mount. When executed from lower filesystem, the lower vnode gets VV_TEXT flag set, and the file cannot be modified while the binary is active. But, if executed as the nullfs alias, only the nullfs vnode gets VV_TEXT set, and you still can open the lower vnode for write. Add a set of VOPs for the VV_TEXT query, set and clear operations, which are correctly bypassed to lower vnode. Tested by: pho (previous version) MFC after: 2 weeks
* Revert r240931, as the previous comment was actually in sync with POSIX.pjd2012-09-271-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | I have to note that POSIX is simply stupid in how it describes O_EXEC/fexecve and friends. Yes, not only inconsistent, but stupid. In the open(2) description, O_RDONLY flag is described as: O_RDONLY Open for reading only. Taken from: http://pubs.opengroup.org/onlinepubs/9699919799/functions/open.html Note "for reading only". Not "for reading or executing"! In the fexecve(2) description you can find: The fexecve() function shall fail if: [EBADF] The fd argument is not a valid file descriptor open for executing. Taken from: http://pubs.opengroup.org/onlinepubs/9699919799/functions/exec.html As you can see the function shall fail if the file was not open with O_EXEC! And yet, if you look closer you can find this mess in the exec.html: Since execute permission is checked by fexecve(), the file description fd need not have been opened with the O_EXEC flag. Yes, O_EXEC flag doesn't have to be specified after all. You can open a file with O_RDONLY and you still be able to fexecve(2) it.
* We cannot open file for reading and executing (O_RDONLY | O_EXEC).pjd2012-09-251-3/+3
| | | | | | | | | | Well, in theory we can pass those two flags, because O_RDONLY is 0, but we won't be able to read from a descriptor opened with O_EXEC. Update the comment. Sponsored by: FreeBSD Foundation MFC after: 2 weeks
* Unbreak handling of descriptors opened with O_EXEC by fexecve(2).mjg2012-07-081-1/+3
| | | | | | | | | | | While here return EBADF for descriptors opened for writing (previously it was ETXTBSY). Add fgetvp_exec function which performs appropriate checks. PR: kern/169651 In collaboration with: kib Approved by: trasz (mentor) MFC after: 1 week
* Move the code dealing with shared page into a dedicatedkib2012-06-231-192/+0
| | | | | | kern_sharedpage.c source file from kern_exec.c. MFC after: 29 days
* Stop updating the struct vdso_timehands from even handler executed inkib2012-06-231-54/+43
| | | | | | | | | | | | | | | | | | | | | | the scheduled task from tc_windup(). Do it directly from tc_windup in interrupt context [1]. Establish the permanent mapping of the shared page into the kernel address space, avoiding the potential need to sleep waiting for allocation of sf buffer during vdso_timehands update. As a consequence, shared_page_write_start() and shared_page_write_end() functions are not needed anymore. Guess and memorize the pointers to native host and compat32 sysentvec during initialization, to avoid the need to get shared_page_alloc_sx lock during the update. In tc_fill_vdso_timehands(), do not loop waiting for timehands generation to stabilize, since vdso_timehands is written in the same interrupt context which wrote timehands. Requested by: mav [1] MFC after: 29 days
* Implement mechanism to export some kernel timekeeping data tokib2012-06-221-0/+93
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | usermode, using shared page. The structures and functions have vdso prefix, to indicate the intended location of the code in some future. The versioned per-algorithm data is exported in the format of struct vdso_timehands, which mostly repeats the content of in-kernel struct timehands. Usermode reading of the structure can be lockless. Compatibility export for 32bit processes on 64bit host is also provided. Kernel also provides usermode with indication about currently used timecounter, so that libc can fall back to syscall if configured timecounter is unknown to usermode code. The shared data updates are initiated both from the tc_windup(), where a fast task is queued to do the update, and from sysctl handlers which change timecounter. A manual override switch kern.timecounter.fast_gettime allows to turn off the mechanism. Only x86 architectures export the real algorithm data, and there, only for tsc timecounter. HPET counters page could be exported as well, but I prefer to not further glue the kernel and libc ABI there until proper vdso-based solution is developed. Minimal stubs neccessary for non-x86 architectures to still compile are provided. Discussed with: bde Reviewed by: jhb Tested by: flo MFC after: 1 month
* Enchance the shared page chunk allocator.kib2012-06-221-14/+63
| | | | | | | | | | | | | | | | Do not rely on the busy state of the page from which we allocate the chunk, to protect allocator state. Use statically allocated sx lock instead. Provide more flexible KPI. In particular, allow to allocate chunk without providing initial data, and allow writes into existing allocation. Allow to get an sf buf which temporary maps the chunk, to allow sequential updates to shared page content without unmapping in between. Reviewed by: jhb Tested by: flo MFC after: 1 month
* Add a new sched_clear_name() method to the scheduler interface to clearjhb2012-03-081-0/+4
| | | | | | | | the cached name used for KTR_SCHED traces when a thread's name changes. This way KTR_SCHED traces (and thus schedgraph) will notice when a thread's name changes, most commonly via execve(). MFC after: 2 weeks
* Use shared lock for the executable vnode in the exec path after thekib2012-01-191-5/+8
| | | | | | | | VV_TEXT changes are handled. Assert that vnode is exclusively locked at the places that modify VV_TEXT. Discussed with: alc MFC after: 3 weeks
* Do not deliver SIGTRAP on exec as the normal signal, use ptracestop() onkib2011-09-271-10/+0
| | | | | | | | | | syscall exit path. Otherwise, if SIGTRAP is ignored, that tdsendsignal() do not want to deliver the signal, and debugger never get a notification of exec. Found and tested by: Anton Yuzhaninov <citrin citrin ru> Discussed with: jhb MFC after: 2 weeks
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