aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/fork.c (follow)
AgeCommit message (Collapse)AuthorFilesLines
2007-02-12[PATCH] tty: update the tty layer to work with struct pidEric W. Biederman1-1/+1
Of kernel subsystems that work with pids the tty layer is probably the largest consumer. But it has the nice virtue that the assiation with a session only lasts until the session leader exits. Which means that no reference counting is required. So using struct pid winds up being a simple optimization to avoid hash table lookups. In the long term the use of pid_nr also ensures that when we have multiple pid spaces mixed everything will work correctly. Signed-off-by: Eric W. Biederman <eric@maxwell.lnxi.com> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Oleg Nesterov <oleg@tv-sign.ru> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-11[PATCH] ifdef ->rchar, ->wchar, ->syscr, ->syscw from task_structAlexey Dobriyan1-0/+2
They are fat: 4x8 bytes in task_struct. They are uncoditionally updated in every fork, read, write and sendfile. They are used only if you have some "extended acct fields feature". And please, please, please, read(2) knows about bytes, not characters, why it is called "rchar"? Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-01[PATCH] fork_idle() should be __cpuinit, not __devinitAl Viro1-1/+1
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30Revert "[PATCH] namespaces: fix exit race by splitting exit"Linus Torvalds1-2/+2
This reverts commit 7a238fcba0629b6f2edbcd37458bae56fcf36be5 in preparation for a better and simpler fix proposed by Eric Biederman (and fixed up by Serge Hallyn) Acked-by: Serge E. Hallyn <serue@us.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30[PATCH] namespaces: fix exit race by splitting exitSerge E. Hallyn1-2/+2
Fix exit race by splitting the nsproxy putting into two pieces. First piece reduces the nsproxy refcount. If we dropped the last reference, then it puts the mnt_ns, and returns the nsproxy as a hint to the caller. Else it returns NULL. The second piece of exiting task namespaces sets tsk->nsproxy to NULL, and drops the references to other namespaces and frees the nsproxy only if an nsproxy was passed in. A little awkward and should probably be reworked, but hopefully it fixes the NFS oops. Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Oleg Nesterov <oleg@tv-sign.ru> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Daniel Hokka Zakrisson <daniel@hozac.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-13[PATCH] Optimize D-cache alias handling on forkRalf Baechle1-1/+1
Virtually index, physically tagged cache architectures can get away without cache flushing when forking. This patch adds a new cache flushing function flush_cache_dup_mm(struct mm_struct *) which for the moment I've implemented to do the same thing on all architectures except on MIPS where it's a no-op. Signed-off-by: Ralf Baechle <ralf@linux-mips.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10[PATCH] fdtable: Remove the free_files fieldVadim Lobanov1-1/+0
An fdtable can either be embedded inside a files_struct or standalone (after being expanded). When an fdtable is being discarded after all RCU references to it have expired, we must either free it directly, in the standalone case, or free the files_struct it is contained within, in the embedded case. Currently the free_files field controls this behavior, but we can get rid of it entirely, as all the necessary information is already recorded. We can distinguish embedded and standalone fdtables using max_fds, and if it is embedded we can divine the relevant files_struct using container_of(). Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10[PATCH] fdtable: Make fdarray and fdsets equal in sizeVadim Lobanov1-18/+6
Currently, each fdtable supports three dynamically-sized arrays of data: the fdarray and two fdsets. The code allows the number of fds supported by the fdarray (fdtable->max_fds) to differ from the number of fds supported by each of the fdsets (fdtable->max_fdset). In practice, it is wasteful for these two sizes to differ: whenever we hit a limit on the smaller-capacity structure, we will reallocate the entire fdtable and all the dynamic arrays within it, so any delta in the memory used by the larger-capacity structure will never be touched at all. Rather than hogging this excess, we shouldn't even allocate it in the first place, and keep the capacities of the fdarray and the fdsets equal. This patch removes fdtable->max_fdset. As an added bonus, most of the supporting code becomes simpler. Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Dipankar Sarma <dipankar@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10[PATCH] fdtable: Delete pointless code in dup_fd()Vadim Lobanov1-6/+5
The dup_fd() function creates a new files_struct and fdtable embedded inside that files_struct, and then possibly expands the fdtable using expand_files(). The out_release error path is invoked when expand_files() returns an error code. However, when this attempt to expand fails, the fdtable is left in its original embedded form, so it is pointless to try to free the associated fdarray and fdsets. Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net> Cc: Dipankar Sarma <dipankar@in.ibm.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-10[PATCH] io-accounting: core statisticsAndrew Morton1-0/+2
The present per-task IO accounting isn't very useful. It simply counts the number of bytes passed into read() and write(). So if a process reads 1MB from an already-cached file, it is accused of having performed 1MB of I/O, which is wrong. (David Wright had some comments on the applicability of the present logical IO accounting: For billing purposes it is useless but for workload analysis it is very useful read_bytes/read_calls average read request size write_bytes/write_calls average write request size read_bytes/read_blocks ie logical/physical can indicate hit rate or thrashing write_bytes/write_blocks ie logical/physical guess since pdflush writes can be missed I often look for logical larger than physical to see filesystem cache problems. And the bytes/cpusec can help find applications that are dominating the cache and causing slow interactive response from page cache contention. I want to find the IO intensive applications and make sure they are doing efficient IO. Thus the acctcms(sysV) or csacms command would give the high IO commands). This patchset adds new accounting which tries to be more accurate. We account for three things: reads: attempt to count the number of bytes which this process really did cause to be fetched from the storage layer. Done at the submit_bio() level, so it is accurate for block-backed filesystems. I also attempt to wire up NFS and CIFS. writes: attempt to count the number of bytes which this process caused to be sent to the storage layer. This is done at page-dirtying time. The big inaccuracy here is truncate. If a process writes 1MB to a file and then deletes the file, it will in fact perform no writeout. But it will have been accounted as having caused 1MB of write. So... cancelled_writes: account the number of bytes which this process caused to not happen, by truncating pagecache. We _could_ just subtract this from the process's `write' accounting. But that means that some processes would be reported to have done negative amounts of write IO, which is silly. So we just report the raw number and punt this decision up to userspace. Now, we _could_ account for writes at the physical I/O level. But - This would require that we track memory-dirtying tasks at the per-page level (would require a new pointer in struct page). - It would mean that IO statistics for a process are usually only available long after that process has exitted. Which means that we probably cannot communicate this info via taskstats. This patch: Wire up the kernel-private data structures and the accessor functions to manipulate them. Cc: Jay Lan <jlan@sgi.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Chris Sturtivant <csturtiv@sgi.com> Cc: Tony Ernst <tee@sgi.com> Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net> Cc: David Wright <daw@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] rename struct namespace to struct mnt_namespaceKirill Korotaev1-10/+11
Rename 'struct namespace' to 'struct mnt_namespace' to avoid confusion with other namespaces being developped for the containers : pid, uts, ipc, etc. 'namespace' variables and attributes are also renamed to 'mnt_ns' Signed-off-by: Kirill Korotaev <dev@sw.ru> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] add process_session() helper routine: deprecate old fieldCedric Le Goater1-1/+1
Add an anonymous union and ((deprecated)) to catch direct usage of the session field. [akpm@osdl.org: fix various missed conversions] [jdike@addtoit.com: fix UML bug] Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] add process_session() helper routineCedric Le Goater1-2/+2
Replace occurences of task->signal->session by a new process_session() helper routine. It will be useful for pid namespaces to abstract the session pid number. Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] kernel: change uses of f_{dentry, vfsmnt} to use f_pathJosef "Jeff" Sipek1-1/+1
Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in linux/kernel/. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-08[PATCH] sys_unshare: remove a broken CLONE_SIGHAND codeOleg Nesterov1-12/+4
sys_unshare(CLONE_SIGHAND) is broken, the code under 'if (new_sigh)' is never executed but very wrong. Just remove it to avoid a confusion, task_lock() has nothing to do with ->sighand changing. Also, change the comment in unshare_sighand(). Yes, CLONE_THREAD implies CLONE_SIGHAND, but still it looks confusing. Also, we don't need to check current->sighand != NULL. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07Merge branch 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6Linus Torvalds1-1/+1
* 'for-linus' of git://one.firstfloor.org/home/andi/git/linux-2.6: (156 commits) [PATCH] x86-64: Export smp_call_function_single [PATCH] i386: Clean up smp_tune_scheduling() [PATCH] unwinder: move .eh_frame to RODATA [PATCH] unwinder: fully support linker generated .eh_frame_hdr section [PATCH] x86-64: don't use set_irq_regs() [PATCH] x86-64: check vector in setup_ioapic_dest to verify if need setup_IO_APIC_irq [PATCH] x86-64: Make ix86 default to HIGHMEM4G instead of NOHIGHMEM [PATCH] i386: replace kmalloc+memset with kzalloc [PATCH] x86-64: remove remaining pc98 code [PATCH] x86-64: remove unused variable [PATCH] x86-64: Fix constraints in atomic_add_return() [PATCH] x86-64: fix asm constraints in i386 atomic_add_return [PATCH] x86-64: Correct documentation for bzImage protocol v2.05 [PATCH] x86-64: replace kmalloc+memset with kzalloc in MTRR code [PATCH] x86-64: Fix numaq build error [PATCH] x86-64: include/asm-x86_64/cpufeature.h isn't a userspace header [PATCH] unwinder: Add debugging output to the Dwarf2 unwinder [PATCH] x86-64: Clarify error message in GART code [PATCH] x86-64: Fix interrupt race in idle callback (3rd try) [PATCH] x86-64: Remove unwind stack pointer alignment forcing again ... Fixed conflict in include/linux/uaccess.h manually Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] taskstats: cleanup ->signal->stats allocationOleg Nesterov1-1/+0
Allocate ->signal->stats on demand in taskstats_exit(), this allows us to remove taskstats_tgid_alloc() (the last non-trivial inline) from taskstat's public interface. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] Disable CLONE_CHILD_CLEARTID for abnormal exitRoland McGrath1-1/+10
The CLONE_CHILD_CLEARTID flag is used by NPTL to have its threads communicate via memory/futex when they exit, so pthread_join can synchronize using a simple futex wait. The word of user memory where NPTL stores a thread's own TID is what it passes; this gets reset to zero at thread exit. It is not desireable to touch this user memory when threads are dying due to a fatal signal. A core dump is more usefully representative of the dying program state if the threads live at the time of the crash have their NPTL data structures unperturbed. The userland expectation of CLONE_CHILD_CLEARTID has only ever been that it works for a thread making an _exit system call. This problem was identified by Ernie Petrides <petrides@redhat.com>. Signed-off-by: Roland McGrath <roland@redhat.com> Cc: Ernie Petrides <petrides@redhat.com> Cc: Jakub Jelinek <jakub@redhat.com> Acked-by: Ingo Molnar <mingo@elte.hu> Cc: Ulrich Drepper <drepper@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] slab: remove kmem_cache_tChristoph Lameter1-8/+8
Replace all uses of kmem_cache_t with struct kmem_cache. The patch was generated using the following script: #!/bin/sh # # Replace one string by another in all the kernel sources. # set -e for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do quilt add $file sed -e "1,\$s/$1/$2/g" $file >/tmp/$$ mv /tmp/$$ $file quilt refresh done The script was run like this sh replace kmem_cache_t "struct kmem_cache" Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] slab: remove SLAB_KERNELChristoph Lameter1-3/+3
SLAB_KERNEL is an alias of GFP_KERNEL. Signed-off-by: Christoph Lameter <clameter@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] new scheme to preempt swap tokenAshwin Chaugule1-0/+8
The new swap token patches replace the current token traversal algo. The old algo had a crude timeout parameter that was used to handover the token from one task to another. This algo, transfers the token to the tasks that are in need of the token. The urgency for the token is based on the number of times a task is required to swap-in pages. Accordingly, the priority of a task is incremented if it has been badly affected due to swap-outs. To ensure that the token doesnt bounce around rapidly, the token holders are given a priority boost. The priority of tasks is also decremented, if their rate of swap-in's keeps reducing. This way, the condition to check whether to pre-empt the swap token, is a matter of comparing two task's priority fields. [akpm@osdl.org: cleanups] Signed-off-by: Ashwin Chaugule <ashwin.chaugule@celunite.com> Cc: Rik van Riel <riel@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-07[PATCH] i386: Use %gs as the PDA base-segment in the kernelJeremy Fitzhardinge1-1/+1
This patch is the meat of the PDA change. This patch makes several related changes: 1: Most significantly, %gs is now used in the kernel. This means that on entry, the old value of %gs is saved away, and it is reloaded with __KERNEL_PDA. 2: entry.S constructs the stack in the shape of struct pt_regs, and this is passed around the kernel so that the process's saved register state can be accessed. Unfortunately struct pt_regs doesn't currently have space for %gs (or %fs). This patch extends pt_regs to add space for gs (no space is allocated for %fs, since it won't be used, and it would just complicate the code in entry.S to work around the space). 3: Because %gs is now saved on the stack like %ds, %es and the integer registers, there are a number of places where it no longer needs to be handled specially; namely context switch, and saving/restoring the register state in a signal context. 4: And since kernel threads run in kernel space and call normal kernel code, they need to be created with their %gs == __KERNEL_PDA. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: Chuck Ebbert <76306.1226@compuserve.com> Cc: Zachary Amsden <zach@vmware.com> Cc: Jan Beulich <jbeulich@novell.com> Cc: Andi Kleen <ak@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org>
2006-11-25[PATCH] fix copy_process() error checkAkinobu Mita1-3/+2
The return value of copy_process() should be checked by IS_ERR(). Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-14Revert "[PATCH] fix Data Acess error in dup_fd"Linus Torvalds1-1/+0
This reverts commit 0130b0b32ee53dc7add773fcea984f6a26ef1da3. Sergey Vlasov points out (and Vadim Lobanov concurs) that the bug it was supposed to fix must be some unrelated memory corruption, and the "fix" actually causes more problems: "However, the new code does not look safe in all cases. If some other task has opened more files while dup_fd() released oldf->file_lock, the new code will update open_files to the new larger value. But newf was allocated with the old smaller value of open_files, therefore subsequent accesses to newf may try to write into unallocated memory." so revert it. Cc: Sharyathi Nagesh <sharyath@in.ibm.com> Cc: Sergey Vlasov <vsu@altlinux.ru> Cc: Vadim Lobanov <vlobanov@speakeasy.net> Cc: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-13[PATCH] fix Data Acess error in dup_fdSharyathi Nagesh1-0/+1
On running the Stress Test on machine for more than 72 hours following error message was observed. 0:mon> e cpu 0x0: Vector: 300 (Data Access) at [c00000007ce2f7f0] pc: c000000000060d90: .dup_fd+0x240/0x39c lr: c000000000060d6c: .dup_fd+0x21c/0x39c sp: c00000007ce2fa70 msr: 800000000000b032 dar: ffffffff00000028 dsisr: 40000000 current = 0xc000000074950980 paca = 0xc000000000454500 pid = 27330, comm = bash 0:mon> t [c00000007ce2fa70] c000000000060d28 .dup_fd+0x1d8/0x39c (unreliable) [c00000007ce2fb30] c000000000060f48 .copy_files+0x5c/0x88 [c00000007ce2fbd0] c000000000061f5c .copy_process+0x574/0x1520 [c00000007ce2fcd0] c000000000062f88 .do_fork+0x80/0x1c4 [c00000007ce2fdc0] c000000000011790 .sys_clone+0x5c/0x74 [c00000007ce2fe30] c000000000008950 .ppc_clone+0x8/0xc The problem is because of race window. When if(expand) block is executed in dup_fd unlocking of oldf->file_lock give a window for fdtable in oldf to be modified. So actual open_files in oldf may not match with open_files variable. Cc: Vadim Lobanov <vlobanov@speakeasy.net> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] taskstats: kill ->taskstats_lock in favor of ->siglockOleg Nesterov1-1/+1
signal_struct is (mostly) protected by ->sighand->siglock, I think we don't need ->taskstats_lock to protect ->stats. This also allows us to simplify the locking in fill_tgid(). Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-28[PATCH] taskstats_tgid_free: fix usageOleg Nesterov1-1/+0
taskstats_tgid_free() is called on copy_process's error path. This is wrong. IF (clone_flags & CLONE_THREAD) We should not clear ->signal->taskstats, current uses it, it probably has a valid accumulated info. ELSE taskstats_tgid_init() set ->signal->taskstats = NULL, there is nothing to free. Move the callsite to __exit_signal(). We don't need any locking, entire thread group is exiting, nobody should have a reference to soon to be released ->signal. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-17[PATCH] rt-mutex: fixup rt-mutex debug codePeter Zijlstra1-2/+2
BUG: warning at kernel/rtmutex-debug.c:125/rt_mutex_debug_task_free() (Not tainted) [<c04051e3>] show_trace_log_lvl+0x58/0x16a [<c04057f0>] show_trace+0xd/0x10 [<c0405900>] dump_stack+0x19/0x1b [<c043f03d>] rt_mutex_debug_task_free+0x35/0x6a [<c04224c0>] free_task+0x15/0x24 [<c042378c>] copy_process+0x12bd/0x1324 [<c0423835>] do_fork+0x42/0x113 [<c04021dd>] sys_fork+0x19/0x1b [<c0403fb7>] syscall_call+0x7/0xb In copy_process(), dup_task_struct() also duplicates the ->pi_lock, ->pi_waiters and ->pi_blocked_on members. rt_mutex_debug_task_free() called from free_task() validates these members. However free_task() can be invoked before these members are reset for the new task. Move the initialization code before the first bail that can hit free_task(). Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] IPC namespace - utilsKirill Korotaev1-0/+10
This patch adds basic IPC namespace functionality to IPC utils: - init_ipc_ns - copy/clone/unshare/free IPC ns - /proc preparations Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] IPC namespace coreKirill Korotaev1-4/+18
This patch set allows to unshare IPCs and have a private set of IPC objects (sem, shm, msg) inside namespace. Basically, it is another building block of containers functionality. This patch implements core IPC namespace changes: - ipc_namespace structure - new config option CONFIG_IPC_NS - adds CLONE_NEWIPC flag - unshare support [clg@fr.ibm.com: small fix for unshare of ipc namespace] [akpm@osdl.org: build fix] Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: Kirill Korotaev <dev@openvz.org> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] uts: copy nsproxy only when neededSerge Hallyn1-6/+14
The nsproxy was being copied in unshare() when anything was being unshared, even if it was something not referenced from nsproxy. This should end up in some cases with far more memory usage than necessary. Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] namespaces: utsname: implement CLONE_NEWUTS flagSerge E. Hallyn1-3/+17
Implement a CLONE_NEWUTS flag, and use it at clone and sys_unshare. [clg@fr.ibm.com: IPC unshare fix] [bunk@stusta.de: cleanup] Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] namespaces: incorporate fs namespace into nsproxySerge E. Hallyn1-11/+6
This moves the mount namespace into the nsproxy. The mount namespace count now refers to the number of nsproxies point to it, rather than the number of tasks. As a result, the unshare_namespace() function in kernel/fork.c no longer checks whether it is being shared. Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02[PATCH] namespaces: add nsproxySerge E. Hallyn1-1/+17
This patch adds a nsproxy structure to the task struct. Later patches will move the fs namespace pointer into this structure, and introduce a new utsname namespace into the nsproxy. The vserver and openvz functionality, then, would be implemented in large part by virtualizing/isolating more and more resources into namespaces, each contained in the nsproxy. [akpm@osdl.org: build fix] Signed-off-by: Serge Hallyn <serue@us.ibm.com> Cc: Kirill Korotaev <dev@openvz.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Cc: Herbert Poetzl <herbert@13thfloor.at> Cc: Andrey Savochkin <saw@sw.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] csa: convert CONFIG tag for extended accounting routinesJay Lan1-0/+1
There were a few accounting data/macros that are used in CSA but are #ifdef'ed inside CONFIG_BSD_PROCESS_ACCT. This patch is to change those ifdef's from CONFIG_BSD_PROCESS_ACCT to CONFIG_TASK_XACCT. A few defines are moved from kernel/acct.c and include/linux/acct.h to kernel/tsacct.c and include/linux/tsacct_kern.h. Signed-off-by: Jay Lan <jlan@sgi.com> Cc: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Chris Sturtivant <csturtiv@sgi.com> Cc: Tony Ernst <tee@sgi.com> Cc: Guillaume Thouvenin <guillaume.thouvenin@bull.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] copy_process: cosmetic ->ioprio tweakOleg Nesterov1-6/+3
copy_process: // holds tasklist_lock + ->siglock /* * inherit ioprio */ p->ioprio = current->ioprio; Why? ->ioprio was already copied in dup_task_struct(). I guess this is needed to ensure that the child can't escape sys_ioprio_set(IOPRIO_WHO_{PGRP,USER}), yes? In that case we don't need ->siglock held, and the comment should be updated. Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru> Cc: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-29[PATCH] ifdef blktrace debugging fieldsAlexey Dobriyan1-0/+2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-28Merge branch 'devel' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds1-0/+4
* 'devel' of master.kernel.org:/home/rmk/linux-2.6-arm: (130 commits) [ARM] 3856/1: Add clocksource for Intel IXP4xx platforms [ARM] 3855/1: Add generic time support [ARM] 3873/1: S3C24XX: Add irq_chip names [ARM] 3872/1: S3C24XX: Apply consistant tabbing to irq_chips [ARM] 3871/1: S3C24XX: Fix ordering of EINT4..23 [ARM] nommu: confirms the CR_V bit in nommu mode [ARM] nommu: abort handler fixup for !CPU_CP15_MMU cores. [ARM] 3870/1: AT91: Start removing static memory mappings [ARM] 3869/1: AT91: NAND support for DK and KB9202 boards [ARM] 3868/1: AT91 hardware header update [ARM] 3867/1: AT91 GPIO update [ARM] 3866/1: AT91 clock update [ARM] 3865/1: AT91RM9200 header updates [ARM] 3862/2: S3C2410 - add basic power management support for AML M5900 series [ARM] kthread: switch arch/arm/kernel/apm.c [ARM] Off-by-one in arch/arm/common/icst* [ARM] 3864/1: Refactore sharpsl_pm [ARM] 3863/1: Add Locomo SPI Device [ARM] 3847/2: Convert LOMOMO to use struct device for GPIOs [ARM] Use CPU_CACHE_* where possible in asm/cacheflush.h ...
2006-09-26[PATCH] Add the canary field to the PDA area and the task structArjan van de Ven1-0/+5
This patch adds the per thread cookie field to the task struct and the PDA. Also it makes sure that the PDA value gets the new cookie value at context switch, and that a new task gets a new cookie at task creation time. Signed-off-by: Arjan van Ven <arjan@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andi Kleen <ak@suse.de> CC: Andi Kleen <ak@suse.de>
2006-09-20[ARM] Fix kernel/fork.c for lockdep on ARMRussell King1-0/+4
ARM has interrupts enabled over context switches (iow, has __ARCH_WANT_INTERRUPTS_ON_CTXSW defined.) The lockdep code in fork.c assumes that interrupts are always disabled. Fix this wrong assumption by making the initialisation of 'p->hardirqs_enabled' depend on __ARCH_WANT_INTERRUPTS_ON_CTXSW. Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-09-01[PATCH] task delay accounting fixesShailabh Nagar1-2/+4
Cleanup allocation and freeing of tsk->delays used by delay accounting. This solves two problems reported for delay accounting: 1. oops in __delayacct_blkio_ticks http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1844.html Currently tsk->delays is getting freed too early in task exit which can cause a NULL tsk->delays to get accessed via reading of /proc/<tgid>/stats. The patch fixes this problem by freeing tsk->delays closer to when task_struct itself is freed up. As a result, it also eliminates the use of tsk->delays_lock which was only being used (inadequately) to safeguard access to tsk->delays while a task was exiting. 2. Possible memory leak in kernel/delayacct.c http://www.uwsg.indiana.edu/hypermail/linux/kernel/0608.2/1389.html The patch cleans up tsk->delays allocations after a bad fork which was missing earlier. The patch has been tested to fix the problems listed above and stress tested with rapid calls to delay accounting's taskstats command interface (which is the other path that can access the same data, besides the /proc interface causing the oops above). Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com> Cc: Balbir Singh <balbir@in.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-08-06[PATCH] ptrace: make pid of child process available for PTRACE_EVENT_VFORK_DONEChuck Ebbert1-1/+3
When delivering PTRACE_EVENT_VFORK_DONE, provide pid of the child process when tracer calls ptrace(PTRACE_GETEVENTMSG). This is already (accidentally) available when the tracer is tracing VFORK in addition to VFORK_DONE. Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com> Cc: Daniel Jacobowitz <dan@debian.org> Cc: Albert Cahalan <acahalan@gmail.com> Cc: Roland McGrath <roland@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14[PATCH] delay accounting taskstats interface send tgid onceShailabh Nagar1-0/+4
Send per-tgid data only once during exit of a thread group instead of once with each member thread exit. Currently, when a thread exits, besides its per-tid data, the per-tgid data of its thread group is also sent out, if its thread group is non-empty. The per-tgid data sent consists of the sum of per-tid stats for all *remaining* threads of the thread group. This patch modifies this sending in two ways: - the per-tgid data is sent only when the last thread of a thread group exits. This cuts down heavily on the overhead of sending/receiving per-tgid data, especially when other exploiters of the taskstats interface aren't interested in per-tgid stats - the semantics of the per-tgid data sent are changed. Instead of being the sum of per-tid data for remaining threads, the value now sent is the true total accumalated statistics for all threads that are/were part of the thread group. The patch also addresses a minor issue where failure of one accounting subsystem to fill in the taskstats structure was causing the send of taskstats to not be sent at all. The patch has been tested for stability and run cerberus for over 4 hours on an SMP. [akpm@osdl.org: bugfixes] Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by: Balbir Singh <balbir@in.ibm.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-14[PATCH] per-task-delay-accounting: setupShailabh Nagar1-0/+2
Initialization code related to collection of per-task "delay" statistics which measure how long it had to wait for cpu, sync block io, swapping etc. The collection of statistics and the interface are in other patches. This patch sets up the data structures and allows the statistics collection to be disabled through a kernel boot parameter. Signed-off-by: Shailabh Nagar <nagar@watson.ibm.com> Signed-off-by: Balbir Singh <balbir@in.ibm.com> Cc: Jes Sorensen <jes@sgi.com> Cc: Peter Chubb <peterc@gelato.unsw.edu.au> Cc: Erich Focht <efocht@ess.nec.de> Cc: Levent Serinol <lserinol@gmail.com> Cc: Jay Lan <jlan@engr.sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10[PATCH] remove the tasklist_lock exportChristoph Hellwig1-3/+1
As announced half a year ago this patch will remove the tasklist_lock export. The previous two patches got rid of the remaining modular users. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] sched: cleanup, remove task_t, convert to struct task_structIngo Molnar1-9/+9
cleanup: remove task_t and convert all the uses to struct task_struct. I introduced it for the scheduler anno and it was a mistake. Conversion was mostly scripted, the result was reviewed and all secondary whitespace and style impact (if any) was fixed up by hand. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: annotate ->mmap_semIngo Molnar1-1/+4
Teach special (recursive) locking code to the lock validator. Has no effect on non-lockdep kernels. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: coreIngo Molnar1-0/+5
Do 'make oldconfig' and accept all the defaults for new config options - reboot into the kernel and if everything goes well it should boot up fine and you should have /proc/lockdep and /proc/lockdep_stats files. Typically if the lock validator finds some problem it will print out voluminous debug output that begins with "BUG: ..." and which syslog output can be used by kernel developers to figure out the precise locking scenario. What does the lock validator do? It "observes" and maps all locking rules as they occur dynamically (as triggered by the kernel's natural use of spinlocks, rwlocks, mutexes and rwsems). Whenever the lock validator subsystem detects a new locking scenario, it validates this new rule against the existing set of rules. If this new rule is consistent with the existing set of rules then the new rule is added transparently and the kernel continues as normal. If the new rule could create a deadlock scenario then this condition is printed out. When determining validity of locking, all possible "deadlock scenarios" are considered: assuming arbitrary number of CPUs, arbitrary irq context and task context constellations, running arbitrary combinations of all the existing locking scenarios. In a typical system this means millions of separate scenarios. This is why we call it a "locking correctness" validator - for all rules that are observed the lock validator proves it with mathematical certainty that a deadlock could not occur (assuming that the lock validator implementation itself is correct and its internal data structures are not corrupted by some other kernel subsystem). [see more details and conditionals of this statement in include/linux/lockdep.h and Documentation/lockdep-design.txt] Furthermore, this "all possible scenarios" property of the validator also enables the finding of complex, highly unlikely multi-CPU multi-context races via single single-context rules, increasing the likelyhood of finding bugs drastically. In practical terms: the lock validator already found a bug in the upstream kernel that could only occur on systems with 3 or more CPUs, and which needed 3 very unlikely code sequences to occur at once on the 3 CPUs. That bug was found and reported on a single-CPU system (!). So in essence a race will be found "piecemail-wise", triggering all the necessary components for the race, without having to reproduce the race scenario itself! In its short existence the lock validator found and reported many bugs before they actually caused a real deadlock. To further increase the efficiency of the validator, the mapping is not per "lock instance", but per "lock-class". For example, all struct inode objects in the kernel have inode->inotify_mutex. If there are 10,000 inodes cached, then there are 10,000 lock objects. But ->inotify_mutex is a single "lock type", and all locking activities that occur against ->inotify_mutex are "unified" into this single lock-class. The advantage of the lock-class approach is that all historical ->inotify_mutex uses are mapped into a single (and as narrow as possible) set of locking rules - regardless of how many different tasks or inode structures it took to build this set of rules. The set of rules persist during the lifetime of the kernel. To see the rough magnitude of checking that the lock validator does, here's a portion of /proc/lockdep_stats, fresh after bootup: lock-classes: 694 [max: 2048] direct dependencies: 1598 [max: 8192] indirect dependencies: 17896 all direct dependencies: 16206 dependency chains: 1910 [max: 8192] in-hardirq chains: 17 in-softirq chains: 105 in-process chains: 1065 stack-trace entries: 38761 [max: 131072] combined max dependencies: 2033928 hardirq-safe locks: 24 hardirq-unsafe locks: 176 softirq-safe locks: 53 softirq-unsafe locks: 137 irq-safe locks: 59 irq-unsafe locks: 176 The lock validator has observed 1598 actual single-thread locking patterns, and has validated all possible 2033928 distinct locking scenarios. More details about the design of the lock validator can be found in Documentation/lockdep-design.txt, which can also found at: http://redhat.com/~mingo/lockdep-patches/lockdep-design.txt [bunk@stusta.de: cleanups] Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: irqtrace subsystem, coreIngo Molnar1-0/+19
Accurate hard-IRQ-flags and softirq-flags state tracing. This allows us to attach extra functionality to IRQ flags on/off events (such as trace-on/off). Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-03[PATCH] lockdep: better lock debuggingIngo Molnar1-4/+0
Generic lock debugging: - generalized lock debugging framework. For example, a bug in one lock subsystem turns off debugging in all lock subsystems. - got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from the mutex/rtmutex debugging code: it caused way too much prototype hackery, and lockdep will give the same information anyway. - ability to do silent tests - check lock freeing in vfree too. - more finegrained debugging options, to allow distributions to turn off more expensive debugging features. There's no separate 'held mutexes' list anymore - but there's a 'held locks' stack within lockdep, which unifies deadlock detection across all lock classes. (this is independent of the lockdep validation stuff - lockdep first checks whether we are holding a lock already) Here are the current debugging options: CONFIG_DEBUG_MUTEXES=y CONFIG_DEBUG_LOCK_ALLOC=y which do: config DEBUG_MUTEXES bool "Mutex debugging, basic checks" config DEBUG_LOCK_ALLOC bool "Detect incorrect freeing of live mutexes" Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>