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* sched/headers: Prepare to move the get_task_struct()/put_task_struct() and ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | related APIs from <linux/sched.h> to <linux/sched/task.h> But first update usage sites with the new header dependency. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar2017-03-021-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | <linux/sched/mm.h> We are going to split <linux/sched/mm.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/mm.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. The APIs that are going to be moved first are: mm_alloc() __mmdrop() mmdrop() mmdrop_async_fn() mmdrop_async() mmget_not_zero() mmput() mmput_async() get_task_mm() mm_access() mm_release() Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
* constify get_dcookie() and friendsAl Viro2016-12-061-1/+1
| | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* oprofile: reduce mmap_sem hold for mm->exe_fileDavidlohr Bueso2015-04-171-14/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | sync_buffer() needs the mmap_sem for two distinct operations, both only occurring upon user context switch handling: 1) Dealing with the exe_file. 2) Adding the dcookie data as we need to lookup the vma that backs it. This is done via add_sample() and add_data(). This patch isolates 1), for it will no longer need the mmap_sem for serialization. However, for now, make of the more standard get_mm_exe_file(), requiring only holding the mmap_sem to read the value, and relying on reference counting to make sure that the exe file won't dissappear underneath us while doing the get dcookie. As a consequence, for 2) we move the mmap_sem locking into where we really need it, in lookup_dcookie(). The benefits are twofold: reduce mmap_sem hold times, and cleaner code. [akpm@linux-foundation.org: export get_mm_exe_file for arch/x86/oprofile/oprofile.ko] Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: Robert Richter <rric@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* mm: use mm->exe_file instead of first VM_EXECUTABLE vma->vm_fileKonstantin Khlebnikov2012-10-091-14/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some security modules and oprofile still uses VM_EXECUTABLE for retrieving a task's executable file. After this patch they will use mm->exe_file directly. mm->exe_file is protected with mm->mmap_sem, so locking stays the same. Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org> Acked-by: Chris Metcalf <cmetcalf@tilera.com> [arch/tile] Acked-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> [tomoyo] Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Carsten Otte <cotte@de.ibm.com> Cc: Cyrill Gorcunov <gorcunov@openvz.org> Cc: Eric Paris <eparis@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Hugh Dickins <hughd@google.com> Cc: Ingo Molnar <mingo@redhat.com> Acked-by: James Morris <james.l.morris@oracle.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Kentaro Takeda <takedakn@nttdata.co.jp> Cc: Matt Helsley <matthltc@us.ibm.com> Cc: Nick Piggin <npiggin@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Robert Richter <robert.richter@amd.com> Cc: Suresh Siddha <suresh.b.siddha@intel.com> Cc: Venkatesh Pallipadi <venki@google.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* oprofile: Fix locking dependency in sync_start()Robert Richter2011-05-311-6/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes the A->B/B->A locking dependency, see the warning below. The function task_exit_notify() is called with (task_exit_notifier) .rwsem set and then calls sync_buffer() which locks buffer_mutex. In sync_start() the buffer_mutex was set to prevent notifier functions to be started before sync_start() is finished. But when registering the notifier, (task_exit_notifier).rwsem is locked too, but now in different order than in sync_buffer(). In theory this causes a locking dependency, what does not occur in practice since task_exit_notify() is always called after the notifier is registered which means the lock is already released. However, after checking the notifier functions it turned out the buffer_mutex in sync_start() is unnecessary. This is because sync_buffer() may be called from the notifiers even if sync_start() did not finish yet, the buffers are already allocated but empty. No need to protect this with the mutex. So we fix this theoretical locking dependency by removing buffer_mutex in sync_start(). This is similar to the implementation before commit: 750d857 oprofile: fix crash when accessing freed task structs which introduced the locking dependency. Lockdep warning: oprofiled/4447 is trying to acquire lock: (buffer_mutex){+.+...}, at: [<ffffffffa0000e55>] sync_buffer+0x31/0x3ec [oprofile] but task is already holding lock: ((task_exit_notifier).rwsem){++++..}, at: [<ffffffff81058026>] __blocking_notifier_call_chain+0x39/0x67 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 ((task_exit_notifier).rwsem){++++..}: [<ffffffff8106557f>] lock_acquire+0xf8/0x11e [<ffffffff81463a2b>] down_write+0x44/0x67 [<ffffffff810581c0>] blocking_notifier_chain_register+0x52/0x8b [<ffffffff8105a6ac>] profile_event_register+0x2d/0x2f [<ffffffffa00013c1>] sync_start+0x47/0xc6 [oprofile] [<ffffffffa00001bb>] oprofile_setup+0x60/0xa5 [oprofile] [<ffffffffa00014e3>] event_buffer_open+0x59/0x8c [oprofile] [<ffffffff810cd3b9>] __dentry_open+0x1eb/0x308 [<ffffffff810cd59d>] nameidata_to_filp+0x60/0x67 [<ffffffff810daad6>] do_last+0x5be/0x6b2 [<ffffffff810dbc33>] path_openat+0xc7/0x360 [<ffffffff810dbfc5>] do_filp_open+0x3d/0x8c [<ffffffff810ccfd2>] do_sys_open+0x110/0x1a9 [<ffffffff810cd09e>] sys_open+0x20/0x22 [<ffffffff8146ad4b>] system_call_fastpath+0x16/0x1b -> #0 (buffer_mutex){+.+...}: [<ffffffff81064dfb>] __lock_acquire+0x1085/0x1711 [<ffffffff8106557f>] lock_acquire+0xf8/0x11e [<ffffffff814634f0>] mutex_lock_nested+0x63/0x309 [<ffffffffa0000e55>] sync_buffer+0x31/0x3ec [oprofile] [<ffffffffa0001226>] task_exit_notify+0x16/0x1a [oprofile] [<ffffffff81467b96>] notifier_call_chain+0x37/0x63 [<ffffffff8105803d>] __blocking_notifier_call_chain+0x50/0x67 [<ffffffff81058068>] blocking_notifier_call_chain+0x14/0x16 [<ffffffff8105a718>] profile_task_exit+0x1a/0x1c [<ffffffff81039e8f>] do_exit+0x2a/0x6fc [<ffffffff8103a5e4>] do_group_exit+0x83/0xae [<ffffffff8103a626>] sys_exit_group+0x17/0x1b [<ffffffff8146ad4b>] system_call_fastpath+0x16/0x1b other info that might help us debug this: 1 lock held by oprofiled/4447: #0: ((task_exit_notifier).rwsem){++++..}, at: [<ffffffff81058026>] __blocking_notifier_call_chain+0x39/0x67 stack backtrace: Pid: 4447, comm: oprofiled Not tainted 2.6.39-00007-gcf4d8d4 #10 Call Trace: [<ffffffff81063193>] print_circular_bug+0xae/0xbc [<ffffffff81064dfb>] __lock_acquire+0x1085/0x1711 [<ffffffffa0000e55>] ? sync_buffer+0x31/0x3ec [oprofile] [<ffffffff8106557f>] lock_acquire+0xf8/0x11e [<ffffffffa0000e55>] ? sync_buffer+0x31/0x3ec [oprofile] [<ffffffff81062627>] ? mark_lock+0x42f/0x552 [<ffffffffa0000e55>] ? sync_buffer+0x31/0x3ec [oprofile] [<ffffffff814634f0>] mutex_lock_nested+0x63/0x309 [<ffffffffa0000e55>] ? sync_buffer+0x31/0x3ec [oprofile] [<ffffffffa0000e55>] sync_buffer+0x31/0x3ec [oprofile] [<ffffffff81058026>] ? __blocking_notifier_call_chain+0x39/0x67 [<ffffffff81058026>] ? __blocking_notifier_call_chain+0x39/0x67 [<ffffffffa0001226>] task_exit_notify+0x16/0x1a [oprofile] [<ffffffff81467b96>] notifier_call_chain+0x37/0x63 [<ffffffff8105803d>] __blocking_notifier_call_chain+0x50/0x67 [<ffffffff81058068>] blocking_notifier_call_chain+0x14/0x16 [<ffffffff8105a718>] profile_task_exit+0x1a/0x1c [<ffffffff81039e8f>] do_exit+0x2a/0x6fc [<ffffffff81465031>] ? retint_swapgs+0xe/0x13 [<ffffffff8103a5e4>] do_group_exit+0x83/0xae [<ffffffff8103a626>] sys_exit_group+0x17/0x1b [<ffffffff8146ad4b>] system_call_fastpath+0x16/0x1b Reported-by: Marcin Slusarz <marcin.slusarz@gmail.com> Cc: Carl Love <carll@us.ibm.com> Cc: <stable@kernel.org> # .36+ Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: Free potentially owned tasks in case of errorsRobert Richter2011-05-311-4/+9
| | | | | | | | | After registering the task free notifier we possibly have tasks in our dying_tasks list. Free them after unregistering the notifier in case of an error. Cc: <stable@kernel.org> # .36+ Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: Remove deprecated use of flush_scheduled_work()Tejun Heo2010-10-291-1/+1
| | | | | | | | | | | | | | flush_scheduled_work() is deprecated and scheduled to be removed. sync_stop() currently cancels cpu_buffer works inside buffer_mutex and flushes the system workqueue outside. Instead, split end_cpu_work() into two parts - stopping further work enqueues and flushing works - and do the former inside buffer_mutex and latter outside. For stable kernels v2.6.35.y and v2.6.36.y. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@kernel.org Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: fix crash when accessing freed task structsRobert Richter2010-08-251-13/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch fixes a crash during shutdown reported below. The crash is caused by accessing already freed task structs. The fix changes the order for registering and unregistering notifier callbacks. All notifiers must be initialized before buffers start working. To stop buffer synchronization we cancel all workqueues, unregister the notifier callback and then flush all buffers. After all of this we finally can free all tasks listed. This should avoid accessing freed tasks. On 22.07.10 01:14:40, Benjamin Herrenschmidt wrote: > So the initial observation is a spinlock bad magic followed by a crash > in the spinlock debug code: > > [ 1541.586531] BUG: spinlock bad magic on CPU#5, events/5/136 > [ 1541.597564] Unable to handle kernel paging request for data at address 0x6b6b6b6b6b6b6d03 > > Backtrace looks like: > > spin_bug+0x74/0xd4 > ._raw_spin_lock+0x48/0x184 > ._spin_lock+0x10/0x24 > .get_task_mm+0x28/0x8c > .sync_buffer+0x1b4/0x598 > .wq_sync_buffer+0xa0/0xdc > .worker_thread+0x1d8/0x2a8 > .kthread+0xa8/0xb4 > .kernel_thread+0x54/0x70 > > So we are accessing a freed task struct in the work queue when > processing the samples. Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: stable@kernel.org Signed-off-by: Robert Richter <robert.richter@amd.com>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* cpumask: use zalloc_cpumask_var() where possibleLi Zefan2009-09-241-2/+1
| | | | | | | Remove open-coded zalloc_cpumask_var() and zalloc_cpumask_var_node(). Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* cpumask: modifiy oprofile initializationRobert Richter2009-01-221-14/+6
| | | | | | | | | | | Delta patch to f7df8ed164996cd2c6aca9674388be6ef78d8b37 for tip/cpus4096. Moved initialization to sync_start()/sync_stop(). No changes needed in buffer_sync.h and oprof.c anymore. Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* cpumask: convert misc driver functionsRusty Russell2009-01-111-4/+18
| | | | | | | | | | | | | | | | | | | | | | Impact: use new cpumask API. Convert misc driver functions to use struct cpumask. To Do: - Convert iucv_buffer_cpumask to cpumask_var_t. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Dean Nelson <dcn@sgi.com> Cc: Robert Richter <robert.richter@amd.com> Cc: oprofile-list@lists.sf.net Cc: Jeremy Fitzhardinge <jeremy@xensource.com> Cc: Chris Wright <chrisw@sous-sol.org> Cc: virtualization@lists.osdl.org Cc: xen-devel@lists.xensource.com Cc: Ursula Braun <ursula.braun@de.ibm.com> Cc: linux390@de.ibm.com Cc: linux-s390@vger.kernel.org
* Merge branch 'for-linus' of ↵Linus Torvalds2009-01-091-109/+79
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile: (31 commits) powerpc/oprofile: fix whitespaces in op_model_cell.c powerpc/oprofile: IBM CELL: add SPU event profiling support powerpc/oprofile: fix cell/pr_util.h powerpc/oprofile: IBM CELL: cleanup and restructuring oprofile: make new cpu buffer functions part of the api oprofile: remove #ifdef CONFIG_OPROFILE_IBS in non-ibs code ring_buffer: fix ring_buffer_event_length() oprofile: use new data sample format for ibs oprofile: add op_cpu_buffer_get_data() oprofile: add op_cpu_buffer_add_data() oprofile: rework implementation of cpu buffer events oprofile: modify op_cpu_buffer_read_entry() oprofile: add op_cpu_buffer_write_reserve() oprofile: rename variables in add_ibs_begin() oprofile: rename add_sample() in cpu_buffer.c oprofile: rename variable ibs_allowed to has_ibs in op_model_amd.c oprofile: making add_sample_entry() inline oprofile: remove backtrace code for ibs oprofile: remove unused ibs macro oprofile: remove unused components in struct oprofile_cpu_buffer ...
| * oprofile: remove #ifdef CONFIG_OPROFILE_IBS in non-ibs codeRobert Richter2009-01-071-6/+0
| | | | | | | | | | | | | | | | The ifdefs can be removed since the code is no longer ibs specific and can be used for other purposes as well. IBS specific code is only in op_model_amd.c. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: use new data sample format for ibsRobert Richter2009-01-071-41/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | The new ring buffer implementation allows the storage of samples with different size. This patch implements the usage of the new sample format to store ibs samples in the cpu buffer. Until now, writing to the cpu buffer could lead to incomplete sampling sequences since IBS samples were transfered in multiple samples. Due to a full buffer, data could be lost at any time. This can't happen any more since the complete data is reserved in advance and then stored in a single sample. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: add op_cpu_buffer_get_data()Robert Richter2009-01-071-2/+4
| | | | | | | | | | | | | | | | | | This function provides access to attached data of a sample. It returns the size of data including the current value. Also, op_cpu_buffer_get_size() is available to check if there is data attached. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: rework implementation of cpu buffer eventsRobert Richter2009-01-071-22/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Special events such as task or context switches are marked with an escape code in the cpu buffer followed by an event code or a task identifier. There is one escape code per event. To make escape sequences also available for data samples the internal cpu buffer format must be changed. The current implementation does not allow the extension of event codes since this would lead to collisions with the task identifiers. To avoid this, this patch introduces an event mask that allows the storage of multiple events with one escape code. Now, task identifiers are stored in the data section of the sample. The implementation also allows the usage of custom data in a sample. As a side effect the new code is much more readable and easier to understand. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: modify op_cpu_buffer_read_entry()Robert Richter2009-01-071-10/+13
| | | | | | | | | | | | This implements the support of samples with attached data. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: rename variables in add_ibs_begin()Robert Richter2009-01-071-13/+13
| | | | | | | | | | | | This unifies usage of variable names within oprofile. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: making add_sample_entry() inlineRobert Richter2009-01-071-1/+1
| | | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: remove backtrace code for ibsRobert Richter2009-01-071-2/+0
| | | | | | | | | | | | | | | | This code is broken since a TRACE_BEGIN_CODE is never sent to the daemon. The data becomes corrupt since the backtrace is interpreted as ibs sample. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: simplify add_ibs_begin()Robert Richter2009-01-071-5/+2
| | | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: simplify sync_buffer()Robert Richter2008-12-291-6/+14
| | | | | | | | | | | | Make code more readable. No functional changes. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: simplify add_sample()Robert Richter2008-12-291-20/+19
| | | | | | | | | | | | | | This patch removes add_us_sample() and simplifies add_sample(). Code is much more readable now. Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: rename cpu buffer functionsRobert Richter2008-12-291-5/+5
| | | | | | | | | | | | | | | | This patch renames cpu buffer functions to something more oprofile specific names. Functions will be moved to the global name space. Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Robert Richter <robert.richter@amd.com>
* | shrink struct dentryNick Piggin2009-01-011-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | struct dentry is one of the most critical structures in the kernel. So it's sad to see it going neglected. With CONFIG_PROFILING turned on (which is probably the common case at least for distros and kernel developers), sizeof(struct dcache) == 208 here (64-bit). This gives 19 objects per slab. I packed d_mounted into a hole, and took another 4 bytes off the inline name length to take the padding out from the end of the structure. This shinks it to 200 bytes. I could have gone the other way and increased the length to 40, but I'm aiming for a magic number, read on... I then got rid of the d_cookie pointer. This shrinks it to 192 bytes. Rant: why was this ever a good idea? The cookie system should increase its hash size or use a tree or something if lookups are a problem. Also the "fast dcookie lookups" in oprofile should be moved into the dcookie code -- how can oprofile possibly care about the dcookie_mutex? It gets dropped after get_dcookie() returns so it can't be providing any sort of protection. At 192 bytes, 21 objects fit into a 4K page, saving about 3MB on my system with ~140 000 entries allocated. 192 is also a multiple of 64, so we get nice cacheline alignment on 64 and 32 byte line systems -- any given dentry will now require 3 cachelines to touch all fields wheras previously it would require 4. I know the inline name size was chosen quite carefully, however with the reduction in cacheline footprint, it should actually be just about as fast to do a name lookup for a 36 character name as it was before the patch (and faster for other sizes). The memory footprint savings for names which are <= 32 or > 36 bytes long should more than make up for the memory cost for 33-36 byte names. Performance is a feature... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* oprofile: port to the new ring_bufferRobert Richter2008-12-101-40/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch replaces the current oprofile cpu buffer implementation with the ring buffer provided by the tracing framework. The motivation here is to leave the pain of implementing ring buffers to others. Oh, no, there are more advantages. Main reason is the support of different sample sizes that could be stored in the buffer. Use cases for this are IBS and Cell spu profiling. Using the new ring buffer ensures valid and complete samples and allows copying the cpu buffer stateless without knowing its content. Second it will use generic kernel API and also reduce code size. And hopefully, there are less bugs. Since the new tracing ring buffer implementation uses spin locks to protect the buffer during read/write access, it is difficult to use the buffer in an NMI handler. In this case, writing to the buffer by the NMI handler (x86) could occur also during critical sections when reading the buffer. To avoid this, there are 2 buffers for independent read and write access. Read access is in process context only, write access only in the NMI handler. If the read buffer runs empty, both buffers are swapped atomically. There is potentially a small window during swapping where the buffers are disabled and samples could be lost. Using 2 buffers is a little bit overhead, but the solution is clear and does not require changes in the ring buffer implementation. It can be changed to a single buffer solution when the ring buffer access is implemented as non-locking atomic code. The new buffer requires more size to store the same amount of samples because each sample includes an u32 header. Also, there is more code to execute for buffer access. Nonetheless, the buffer implementation is proven in the ftrace environment and worth to use also in oprofile. Patches that changes the internal IBS buffer usage will follow. Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: moving cpu_buffer_reset() to cpu_buffer.hRobert Richter2008-12-101-0/+1
| | | | | | This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: adding cpu_buffer_entries()Robert Richter2008-12-101-29/+2
| | | | | | This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: adding cpu buffer r/w access functionsRobert Richter2008-12-101-11/+9
| | | | | | This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: implement switch/case in buffer_sync.cRobert Richter2008-12-101-8/+14
| | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
* oprofile: fix typoRobert Richter2008-12-101-1/+1
| | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2008-10-231-7/+10
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile: (21 commits) OProfile: Fix buffer synchronization for IBS oprofile: hotplug cpu fix oprofile: fixing whitespaces in arch/x86/oprofile/* oprofile: fixing whitespaces in arch/x86/oprofile/* oprofile: fixing whitespaces in drivers/oprofile/* x86/oprofile: add the logic for enabling additional IBS bits x86/oprofile: reordering functions in nmi_int.c x86/oprofile: removing unused function parameter in add_ibs_begin() oprofile: more whitespace fixes oprofile: whitespace fixes OProfile: Rename IBS sysfs dir into "ibs_op" OProfile: Rework string handling in setup_ibs_files() OProfile: Rework oprofile_add_ibs_sample() function oprofile: discover counters for op ppro too oprofile: Implement Intel architectural perfmon support oprofile: Don't report Nehalem as core_2 oprofile: drop const in num counters field Revert "Oprofile Multiplexing Patch" x86, oprofile: BUG: using smp_processor_id() in preemptible code x86/oprofile: fix on_each_cpu build error ... Manually fixed trivial conflicts in drivers/oprofile/{cpu_buffer.c,event_buffer.h}
| * OProfile: Fix buffer synchronization for IBSBarry Kasindorf2008-10-201-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | The patch is needed since there is some IBS code in add_ibs_begin() that handles more than one sample per iteration. This requires calling get_slots() during each loop. This fixes the current problem, but a proper solution that reworks the cpu buffer synchronization is needed here in the future. Signed-off-by: Barry Kasindorf <barry.kasindorf@amd.com> Signed-off-by: Robert Richter <robert.richter@amd.com>
| * x86/oprofile: removing unused function parameter in add_ibs_begin()Robert Richter2008-10-151-5/+3
| | | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
| * oprofile: whitespace fixesRobert Richter2008-10-151-1/+0
| | | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com>
* | powerpc/oprofile: Fix mutex locking for cell spu-oprofileCarl Love2008-10-211-0/+24
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The issue is the SPU code is not holding the kernel mutex lock while adding samples to the kernel buffer. This patch creates per SPU buffers to hold the data. Data is added to the buffers from in interrupt context. The data is periodically pushed to the kernel buffer via a new Oprofile function oprofile_put_buff(). The oprofile_put_buff() function is called via a work queue enabling the funtion to acquire the mutex lock. The existing user controls for adjusting the per CPU buffer size is used to control the size of the per SPU buffers. Similarly, overflows of the SPU buffers are reported by incrementing the per CPU buffer stats. This eliminates the need to have architecture specific controls for the per SPU buffers which is not acceptable to the OProfile user tool maintainer. The export of the oprofile add_event_entry() is removed as it is no longer needed given this patch. Note, this patch has not addressed the issue of indexing arrays by the spu number. This still needs to be fixed as the spu numbering is not guarenteed to be 0 to max_num_spus-1. Signed-off-by: Carl Love <carll@us.ibm.com> Signed-off-by: Maynard Johnson <maynardj@us.ibm.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Acked-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
* x86/oprofile: add CONFIG_OPROFILE_IBS optionRobert Richter2008-07-261-0/+6
| | | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: oprofile-list <oprofile-list@lists.sourceforge.net> Cc: Robert Richter <robert.richter@amd.com> Cc: Barry Kasindorf <barry.kasindorf@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* x86/oprofile: add IBS support for AMD CPUs, IBS buffer handling routinesBarry Kasindorf2008-07-261-1/+71
| | | | | | | | | | This patchset supports the new profiling hardware available in the latest AMD CPUs in the oProfile driver. Signed-off-by: Barry Kasindorf <barry.kasindorf@amd.com> Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: oprofile-list <oprofile-list@lists.sourceforge.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* OProfile: moving increment_tail() in buffer_sync.cRobert Richter2008-07-261-13/+11
| | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: oprofile-list <oprofile-list@lists.sourceforge.net> Cc: Barry Kasindorf <barry.kasindorf@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* drivers/oprofile: coding style fixes in buffer_sync.cRobert Richter2008-07-261-54/+57
| | | | | | | Signed-off-by: Robert Richter <robert.richter@amd.com> Cc: oprofile-list <oprofile-list@lists.sourceforge.net> Cc: Barry Kasindorf <barry.kasindorf@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
* oprofile: change cpu_buffer from array to per_cpu variableMike Travis2008-04-281-1/+1
| | | | | | | | | | Change cpu_buffer from array to per_cpu variable in oprofile functions. [akpm@linux-foundation.org: coding-style fixes] Cc: Philippe Elie <phil.el@wanadoo.fr> Signed-off-by: Mike Travis <travis@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* d_path: Make get_dcookie() use a struct path argumentJan Blunck2008-02-151-12/+9
| | | | | | | | | | | | | | get_dcookie() is always called with a dentry and a vfsmount from a struct path. Make get_dcookie() take it directly as an argument. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Jan Blunck <jblunck@suse.de> Acked-by: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: "J. Bruce Fields" <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [CELL] oprofile: add support to OProfile for profiling CELL BE SPUsBob Nelson2007-07-201-1/+2
| | | | | | | | | | | | | | | | | | | | | | | From: Maynard Johnson <mpjohn@us.ibm.com> This patch updates the existing arch/powerpc/oprofile/op_model_cell.c to add in the SPU profiling capabilities. In addition, a 'cell' subdirectory was added to arch/powerpc/oprofile to hold Cell-specific SPU profiling code. Exports spu_set_profile_private_kref and spu_get_profile_private_kref which are used by OProfile to store private profile information in spufs data structures. Also incorporated several fixes from other patches (rrn). Check pointer returned from kzalloc. Eliminated unnecessary cast. Better error handling and cleanup in the related area. 64-bit unsigned long parameter was being demoted to 32-bit unsigned int and eventually promoted back to unsigned long. Signed-off-by: Carl Love <carll@us.ibm.com> Signed-off-by: Maynard Johnson <mpjohn@us.ibm.com> Signed-off-by: Bob Nelson <rrnelson@us.ibm.com> Signed-off-by: Arnd Bergmann <arnd.bergmann@de.ibm.com> Acked-by: Paul Mackerras <paulus@samba.org>
* Detach sched.h from mm.hAlexey Dobriyan2007-05-211-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | First thing mm.h does is including sched.h solely for can_do_mlock() inline function which has "current" dereference inside. By dealing with can_do_mlock() mm.h can be detached from sched.h which is good. See below, why. This patch a) removes unconditional inclusion of sched.h from mm.h b) makes can_do_mlock() normal function in mm/mlock.c c) exports can_do_mlock() to not break compilation d) adds sched.h inclusions back to files that were getting it indirectly. e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were getting them indirectly Net result is: a) mm.h users would get less code to open, read, preprocess, parse, ... if they don't need sched.h b) sched.h stops being dependency for significant number of files: on x86_64 allmodconfig touching sched.h results in recompile of 4083 files, after patch it's only 3744 (-8.3%). Cross-compile tested on all arm defconfigs, all mips defconfigs, all powerpc defconfigs, alpha alpha-up arm i386 i386-up i386-defconfig i386-allnoconfig ia64 ia64-up m68k mips parisc parisc-up powerpc powerpc-up s390 s390-up sparc sparc-up sparc64 sparc64-up um-x86_64 x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig as well as my two usual configs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] struct path: convert oprofileJosef Sipek2006-12-081-4/+4
| | | | | | Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] oprofile: convert from semaphores to mutexesMarkus Armbruster2006-06-251-4/+4
| | | | | | | | Signed-off-by: Markus Armbruster <armbru@redhat.com> Cc: Philippe Elie <phil.el@wanadoo.fr> Cc: John Levon <levon@movementarian.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] Make RCU task_struct safe for oprofilePaul E. McKenney2006-01-091-15/+15
| | | | | | | | | | | | | | | | | | Applying RCU to the task structure broke oprofile, because free_task_notify() can now be called from softirq. This means that the task_mortuary lock must be acquired with irq disabled in order to avoid intermittent self-deadlock. Since irq is now disabled, the critical section within process_task_mortuary() has been restructured to be O(1) in order to maximize scalability and minimize realtime latency degradation. Kudos to Wu Fengguang for finding this problem! CC: Wu Fengguang <wfg@mail.ustc.edu.cn> Cc: Philippe Elie <phil.el@wanadoo.fr> Cc: John Levon <levon@movementarian.org> Signed-off-by: "Paul E. McKenney" <paulmck@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] oprofile: report anonymous region samplesJohn Levon2005-06-241-11/+18
| | | | | | | | | | | | | | | | The below patch passes samples from anonymous regions to userspace instead of just dropping them. This provides the support needed for reporting anonymous-region code samples (today: basic accumulated results; later: Java and other dynamically compiled code). As this changes the format, an upgrade to the just-released 0.9 release of the userspace tools is required. This patch is based upon an earlier one by Will Cohen <wcohen@redhat.com> Signed-off-by: John Levon <levon@movementarian.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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