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path: root/drivers/oprofile/buffer_sync.c
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2008-12-31shrink struct dentryNick Piggin
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>
2008-12-10oprofile: port to the new ring_bufferRobert Richter
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>
2008-12-10oprofile: moving cpu_buffer_reset() to cpu_buffer.hRobert Richter
This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10oprofile: adding cpu_buffer_entries()Robert Richter
This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10oprofile: adding cpu buffer r/w access functionsRobert Richter
This is in preparation for changes in the cpu buffer implementation. Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10oprofile: implement switch/case in buffer_sync.cRobert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-10oprofile: fix typoRobert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-23Merge branch 'for-linus' of ↵Linus Torvalds
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}
2008-10-21powerpc/oprofile: Fix mutex locking for cell spu-oprofileCarl Love
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>
2008-10-20OProfile: Fix buffer synchronization for IBSBarry Kasindorf
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>
2008-10-15x86/oprofile: removing unused function parameter in add_ibs_begin()Robert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-15oprofile: whitespace fixesRobert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-07-26x86/oprofile: add CONFIG_OPROFILE_IBS optionRobert Richter
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>
2008-07-26x86/oprofile: add IBS support for AMD CPUs, IBS buffer handling routinesBarry Kasindorf
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>
2008-07-26OProfile: moving increment_tail() in buffer_sync.cRobert Richter
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>
2008-07-26drivers/oprofile: coding style fixes in buffer_sync.cRobert Richter
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>
2008-04-28oprofile: change cpu_buffer from array to per_cpu variableMike Travis
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>
2008-02-14d_path: Make get_dcookie() use a struct path argumentJan Blunck
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>
2007-07-20[CELL] oprofile: add support to OProfile for profiling CELL BE SPUsBob Nelson
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>
2007-05-21Detach sched.h from mm.hAlexey Dobriyan
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>
2006-12-08[PATCH] struct path: convert oprofileJosef Sipek
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>
2006-06-25[PATCH] oprofile: convert from semaphores to mutexesMarkus Armbruster
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>
2006-01-08[PATCH] Make RCU task_struct safe for oprofilePaul E. McKenney
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>
2005-06-24[PATCH] oprofile: report anonymous region samplesJohn Levon
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>
2005-06-21[PATCH] smp_processor_id() cleanupIngo Molnar
This patch implements a number of smp_processor_id() cleanup ideas that Arjan van de Ven and I came up with. The previous __smp_processor_id/_smp_processor_id/smp_processor_id API spaghetti was hard to follow both on the implementational and on the usage side. Some of the complexity arose from picking wrong names, some of the complexity comes from the fact that not all architectures defined __smp_processor_id. In the new code, there are two externally visible symbols: - smp_processor_id(): debug variant. - raw_smp_processor_id(): nondebug variant. Replaces all existing uses of _smp_processor_id() and __smp_processor_id(). Defined by every SMP architecture in include/asm-*/smp.h. There is one new internal symbol, dependent on DEBUG_PREEMPT: - debug_smp_processor_id(): internal debug variant, mapped to smp_processor_id(). Also, i moved debug_smp_processor_id() from lib/kernel_lock.c into a new lib/smp_processor_id.c file. All related comments got updated and/or clarified. I have build/boot tested the following 8 .config combinations on x86: {SMP,UP} x {PREEMPT,!PREEMPT} x {DEBUG_PREEMPT,!DEBUG_PREEMPT} I have also build/boot tested x64 on UP/PREEMPT/DEBUG_PREEMPT. (Other architectures are untested, but should work just fine.) Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!