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path: root/drivers/oprofile/cpu_buffer.h
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2009-01-17oprofile: fix uninitialized use of struct op_entryRobert Richter
Impact: fix crash In case of losing samples struct op_entry could have been used uninitialized causing e.g. a wrong preemption count or NULL pointer access. This patch fixes this. Signed-off-by: Robert Richter <robert.richter@amd.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-01-07oprofile: make new cpu buffer functions part of the apiRobert Richter
This patch creates the new functions oprofile_write_reserve() oprofile_add_data() oprofile_write_commit() and makes them part of the oprofile api. Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07oprofile: use new data sample format for ibsRobert Richter
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>
2009-01-07oprofile: add op_cpu_buffer_get_data()Robert Richter
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>
2009-01-07oprofile: add op_cpu_buffer_add_data()Robert Richter
This function can be used to attach data to a sample. It returns the remaining free buffer size that has been reserved with op_cpu_buffer_write_reserve(). Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07oprofile: rework implementation of cpu buffer eventsRobert Richter
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>
2009-01-07oprofile: modify op_cpu_buffer_read_entry()Robert Richter
This implements the support of samples with attached data. Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07oprofile: add op_cpu_buffer_write_reserve()Robert Richter
This function prepares the cpu buffer to write a sample. Struct op_entry is used during operations on the ring buffer while struct op_sample contains the data that is stored in the ring buffer. Struct entry can be uninitialized. The function reserves a data array that is specified by size. Use op_cpu_buffer_write_commit() after preparing the sample. In case of errors a null pointer is returned, otherwise the pointer to the sample. Signed-off-by: Robert Richter <robert.richter@amd.com>
2009-01-07oprofile: remove unused components in struct oprofile_cpu_bufferRobert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29oprofile: remove ring buffer inline functions in cpu_buffer.hRobert Richter
This patch moves ring buffer inline functions to cpu_buffer.c. Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-12-29oprofile: rename cpu buffer functionsRobert Richter
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>
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_write_commit()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>
2008-10-16oprofile: fixing whitespaces in drivers/oprofile/*Robert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
2008-10-15oprofile: more whitespace fixesRobert Richter
Signed-off-by: Robert Richter <robert.richter@amd.com>
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>
2008-05-14oprofile: don't request cache line alignment for cpu_bufferEric Dumazet
Alignment was previously requested because cpu_buffer was an [NR_CPUS] array, to avoid cache line sharing between CPUS. After commit 608dfddd845da5ab6accef70154c8910529699f7 (oprofile: change cpu_buffer from array to per_cpu variable ), we dont need to force an alignement anymore since cpu_buffer sits in per_cpu zone. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Cc: Mike Travis <travis@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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>
2007-11-14oProfile: oops when profile_pc() returns ~0LUPhilippe Elie
Instruction pointer returned by profile_pc() can be a random value. This break the assumption than we can safely set struct op_sample.eip field to a magic value to signal to the per-cpu buffer reader side special event like task switch ending up in a segfault in get_task_mm() when profile_pc() return ~0UL. Fixed by sanitizing the sampled eip and reject/log invalid eip. Problem reported by Sami Farin, patch tested by him. Signed-off-by: Philippe Elie <phil.el@wanadoo.fr> Tested-by: Sami Farin <safari-kernel@safari.iki.fi> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-11-22WorkStruct: make allyesconfigDavid Howells
Fix up for make allyesconfig. Signed-Off-By: David Howells <dhowells@redhat.com>
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!