- 27 May, 2015 36 commits
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Arnaldo Carvalho de Melo authored
Now that we have atomic.h, we should convert all of the existing refcounts to use it. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-quzeuy3jwsyod6e06o39cl6y@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Arnaldo Carvalho de Melo authored
To match the convention used elsewhere. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Ahern <dsahern@gmail.com> Cc: Don Zickus <dzickus@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-66oo6yn8upssfeuprwy0il1q@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Namhyung Kim authored
The evsel and sample arguments are to set iter for later use. As it also receives an iter as another argument, just set them before calling the function. Signed-off-by: Namhyung Kim <namhyung@kernel.org> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1432022650-18205-1-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Adrian Hunter authored
perf_session__peek_event() generally leverages there being a single mmap of the perf.data file, however on 32-bit platforms when there is more that 32MiB of data, then there are multiple mmaps, so perf_session__peek_event() reads from the file. In that case a couple of bugs were exposed (note how the seg. fault appears with >32M of data): $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 1000000 [ perf record: Woken up 13 times to write data ] [ perf record: Captured and wrote 24.568 MB perf.data ] $ perf script > /dev/null $ perf record --per-thread -e intel_bts// ../rtit-tests/loopy 10000000 [ perf record: Woken up 136 times to write data ] [ perf record: Captured and wrote 270.794 MB perf.data ] $ perf script > /dev/null Segmentation fault (core dumped) The wrong address was being passed to the readn() function and the buffer size was not being checked. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Link: http://lkml.kernel.org/r/1432040746-1755-5-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Adrian Hunter authored
The libunwind feature would never detect because of the following error: $ cat tools/build/feature/test-libunwind.make.output /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_buffer_decode' /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_uncompressed_size' /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_end' /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_buffer_decode' /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_stream_footer_decode' /usr/lib/gcc/i686-linux-gnu/4.8/../../../i386-linux-gnu/libunwind-x86.so: undefined reference to `lzma_index_size' collect2: error: ld returned 1 exit status Fix by adding -llzma and re-ordering to match the dependencies. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Link: http://lkml.kernel.org/r/1432040746-1755-3-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Adrian Hunter authored
Parse errors can be reported in struct parse_events_error but the pointer passed is optional and can be NULL. Ensure it is not NULL before dereferencing it. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Link: http://lkml.kernel.org/r/1432040746-1755-4-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Adrian Hunter authored
Patch "perf tools: Add location to pmu event terms" moved declarations for parse_events_term__num() and parse_events_term__str() so that they were no longer visible in parse-events.y. That can result in segfaults as the arguments no longer need match the function prototype. Move the declarations back, changing YYLTYPE pointers to pointers-to-void because YYLTYPE is not generated until parse-events.y is processed. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Link: http://lkml.kernel.org/r/1432040746-1755-2-git-send-email-adrian.hunter@intel.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Nam T. Nguyen authored
This refactors out install-bin to install-tests and install-tools so that downstream could opt to only install the tools, and not the tests. Signed-off-by: Nam T. Nguyen <namnguyen@chromium.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Simon Que <sque@chromium.org> Link: http://lkml.kernel.org/r/1431974247-22275-1-git-send-email-namnguyen@chromium.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Alexander Shishkin authored
There is a 'pt' variable in the outer scope of pt_event_stop() with the same type, we don't really need another one in the inner scope. This patch removes the redundant variable declaration. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1432308626-18845-8-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
Initially, we were trying to guard against scenarios where somebody attaches to the system with a hardware debugger while PT is enabled from software and pt_is_running() tries to make sure we handle this better, but the truth is, there is still a race window no matter what and people with hardware debuggers should really know what they are doing anyway. In other words, there is no point in keeping this one around, and it's one RDMSR instructions fewer in the fast path. The case when PT is enabled by the BIOS at boot time is handled in the driver initialization path and doesn't use pt_is_running(). This patch gets rid of it. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1429622177-22843-6-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
Currently, the description of pt_buffer_reset_offsets() lacks information about its calling constraints and ordering with regards to other buffer management functions. Add a clarification about when this function has to be called. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1429622177-22843-5-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
The comments in the driver don't make it absolutely clear as to what exactly is the calling order and other possible constraints of buffer management functions. Document constraints and calling order for the buffer configuration functions. While at it, replace a redundant check in pt_buffer_reset_markers() with an explanation why it is not needed. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1429622177-22843-4-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
Currently, there's a set-but-not-used variable in setup_topa_index(); this patch gets rid of it. And while at it, fixes a style issue with brackets around a one-line block. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1429622177-22843-2-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
Don't bother with taking locks if we're not actually going to do anything. Also, drop the _irqsave(), this is very much only called from IRQ-disabled context. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
!x && y == ! (x || !y) Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
For some obscure reason intel_{start,stop}_scheduling() copy the HT state to an intermediate array. This would make sense if we ever were to make changes to it which we'd have to discard. Except we don't. By the time we call intel_commit_scheduling() we're; as the name implies; committed to them. We'll never back out. A further hint its pointless is that stop_scheduling() unconditionally publishes the state. So the intermediate array is pointless, modify the state in place and kill the extra array. And remove the pointless array initialization: INTEL_EXCL_UNUSED == 0. Note; all is serialized by intel_excl_cntr::lock. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
Both intel_commit_scheduling() and intel_get_excl_contraints() test for cntr < 0. The only way that can happen (aside from a bug) is through validate_event(), however that is already captured by the cpuc->is_fake test. So remove these test and simplify the code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
Move the code of intel_commit_scheduling() to the right place, which is in between start() and stop(). No change in functionality. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
The intel_commit_scheduling() callback is pointlessly different from the start and stop scheduling callback. Furthermore, the constraint should never be NULL, so remove that test. Even though we'll never get called (because we NULL the callbacks) when !is_ht_workaround_enabled() put that test in. Collapse the (pointless) WARN_ON_ONCE() and bail on !cpuc->excl_cntrs -- this is doubly pointless, because its the same condition as is_ht_workaround_enabled() which was already pointless because the whole method won't ever be called. Furthremore, make all the !excl_cntrs test WARN_ON_ONCE(); they're all pointless, because the above, either the function ({get,put}_excl_constraint) are already predicated on it existing or the is_ht_workaround_enabled() thing is the same test. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
We have two 'struct event_constraint' local variables in intel_get_excl_constraints(): 'cx' and 'c'. Instead of using 'cx' after the dynamic allocation, put all 'cx' inside the dynamic allocation block and use 'c' outside of it. Also use direct assignment to copy the structure; let the compiler figure it out. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
Lockdep is very good at finding incorrect IRQ state while locking and is far better at telling us if we hold a lock than the _is_locked() API. It also generates less code for !DEBUG kernels. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
For some obscure reason the current code accounts the current SMT thread's state on the remote thread and reads the remote's state on the local SMT thread. While internally consistent, and 'correct' its pointless confusion we can do without. Flip them the right way around. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Matt Fleming authored
Since we write RMID values to MSRs the correct type to use is 'u32' because that clearly articulates we're writing a hardware register value. Fix up all uses of RMID in this code to consistently use the correct data type. Reported-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Matt Fleming <matt.fleming@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/1432285182-17180-1-git-send-email-matt@codeblueprint.co.ukSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
'closid' (CLass Of Service ID) is used for the Class based Cache Allocation Technology (CAT). Add explicit storage to the per cpu cache for it, so it can be used later with the CAT support (requires to move the per cpu data). While at it: - Rename the structure to intel_pqr_state which reflects the actual purpose of the struct: cache values which go into the PQR MSR - Rename 'cnt' to rmid_usecnt which reflects the actual purpose of the counter. - Document the structure and the struct members. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235150.240899319@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
intel_cqm_event_del() is a 1:1 wrapper for intel_cqm_event_stop(). Remove the useless indirection. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235150.159779847@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
If the usage counter is non-zero there is no point to update the rmid in the PQR MSR. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235150.080844281@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
'struct intel_cqm_state' is a strict per CPU cache of the rmid and the usage counter. It can never be modified from a remote CPU. The three functions which modify the content: intel_cqm_event[start|stop|del] (del maps to stop) are called from the perf core with interrupts disabled which is enough protection for the per CPU state values. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235150.001006529@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
'int' is really not a proper data type for an MSR. Use u32 to make it clear that we are dealing with a 32-bit unsigned hardware value. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235149.919350144@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Thomas Gleixner authored
The CQM code acts like it owns the PQR MSR completely. That's not true because only the lower 10 bits are used for CQM. The upper 32 bits are used for the 'CLass Of Service ID' (CLOSID). Document the abuse. Will be fixed in a later patch. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Matt Fleming <matt.fleming@intel.com> Cc: Kanaka Juvva <kanaka.d.juvva@intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com> Cc: Will Auld <will.auld@intel.com> Link: http://lkml.kernel.org/r/20150518235149.823214798@linutronix.deSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Ingo Molnar authored
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Don Zickus authored
I stumbled upon an AMD box that had the BIOS using a hardware performance counter. Instead of printing out a warning and continuing, it failed and blocked further perf counter usage. Looking through the history, I found this commit: a5ebe0ba ("perf/x86: Check all MSRs before passing hw check") which tweaked the rules for a Xen guest on an almost identical box and now changed the behaviour. Unfortunately the rules were tweaked incorrectly and will always lead to MSR failures even though the MSRs are completely fine. What happens now is in arch/x86/kernel/cpu/perf_event.c::check_hw_exists(): <snip> for (i = 0; i < x86_pmu.num_counters; i++) { reg = x86_pmu_config_addr(i); ret = rdmsrl_safe(reg, &val); if (ret) goto msr_fail; if (val & ARCH_PERFMON_EVENTSEL_ENABLE) { bios_fail = 1; val_fail = val; reg_fail = reg; } } <snip> /* * Read the current value, change it and read it back to see if it * matches, this is needed to detect certain hardware emulators * (qemu/kvm) that don't trap on the MSR access and always return 0s. */ reg = x86_pmu_event_addr(0); ^^^^ if the first perf counter is enabled, then this routine will always fail because the counter is running. :-( if (rdmsrl_safe(reg, &val)) goto msr_fail; val ^= 0xffffUL; ret = wrmsrl_safe(reg, val); ret |= rdmsrl_safe(reg, &val_new); if (ret || val != val_new) goto msr_fail; The above bios_fail used to be a 'goto' which is why it worked in the past. Further, most vendors have migrated to using fixed counters to hide their evilness hence this problem rarely shows up now days except on a few old boxes. I fixed my problem and kept the spirit of the original Xen fix, by recording a safe non-enable register to be used safely for the reading/writing check. Because it is not enabled, this passes on bare metal boxes (like metal), but should continue to throw an msr_fail on Xen guests because the register isn't emulated yet. Now I get a proper bios_fail error message and Xen should still see their msr_fail message (untested). Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: george.dunlap@eu.citrix.com Cc: konrad.wilk@oracle.com Link: http://lkml.kernel.org/r/1431976608-56970-1-git-send-email-dzickus@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
Currently, pt_buffer_reset_markers() is a difficult to read knot of arithmetics with a redundant check for multiple-entry TOPA capability, a commented out wakeup marker placement and a logical error wrt to stop marker placement. The latter happens when write head is not page aligned and results in stop marker being placed one page earlier than it actually should. All these problems only affect PT implementations that support multiple-entry TOPA tables (read: proper scatter-gather). For single-entry TOPA implementations, there is no functional impact. This patch deals with all of the above. Tested on both single-entry and multiple-entry TOPA PT implementations. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1432308626-18845-4-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Alexander Shishkin authored
PMUs that don't support hardware scatter tables require big contiguous chunks of memory and a PMI to switch between them. However, in overwrite using a PMI for this purpose adds extra overhead that the users would like to avoid. Thus, in overwrite mode for such PMUs we can only allow one contiguous chunk for the entire requested buffer. This patch changes the behavior accordingly, so that if the buddy allocator fails to come up with a single high-order chunk for the entire requested buffer, the allocation will fail. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: acme@infradead.org Cc: adrian.hunter@intel.com Cc: hpa@zytor.com Link: http://lkml.kernel.org/r/1432308626-18845-2-git-send-email-alexander.shishkin@linux.intel.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
The (SNB/IVB/HSW) HT bug only affects events that can be programmed onto GP counters, therefore we should only limit the number of GP counters that can be used per cpu -- iow we should not constrain the FP counters. Furthermore, we should only enfore such a limit when there are in fact exclusive events being scheduled on either sibling. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> [ Fixed build fail for the !CONFIG_CPU_SUP_INTEL case. ] Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Peter Zijlstra authored
Commit 43b45780 ("perf/x86: Reduce stack usage of x86_schedule_events()") violated the rule that 'fake' scheduling; as used for event/group validation; should not change the event state. This went mostly un-noticed because repeated calls of x86_pmu::get_event_constraints() would give the same result. And x86_pmu::put_event_constraints() would mostly not do anything. Commit e979121b ("perf/x86/intel: Implement cross-HT corruption bug workaround") made the situation much worse by actually setting the event->hw.constraint value to NULL, so when validation and actual scheduling interact we get NULL ptr derefs. Fix it by removing the constraint pointer from the event and move it back to an array, this time in cpuc instead of on the stack. validate_group() x86_schedule_events() event->hw.constraint = c; # store <context switch> perf_task_event_sched_in() ... x86_schedule_events(); event->hw.constraint = c2; # store ... put_event_constraints(event); # assume failure to schedule intel_put_event_constraints() event->hw.constraint = NULL; <context switch end> c = event->hw.constraint; # read -> NULL if (!test_bit(hwc->idx, c->idxmsk)) # <- *BOOM* NULL deref This in particular is possible when the event in question is a cpu-wide event and group-leader, where the validate_group() tries to add an event to the group. Reported-by: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Hunter <ahh@google.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Fixes: 43b45780 ("perf/x86: Reduce stack usage of x86_schedule_events()") Fixes: e979121b ("perf/x86/intel: Implement cross-HT corruption bug workaround") Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Alexei Starovoitov authored
there is a race between perf_event_free_bpf_prog() and free_trace_kprobe(): __free_event() event->destroy(event) tp_perf_event_destroy() perf_trace_destroy() perf_trace_event_unreg() which is dropping event->tp_event->perf_refcount and allows to proceed in: unregister_trace_kprobe() unregister_kprobe_event() trace_remove_event_call() probe_remove_event_call() free_trace_kprobe() while __free_event does: call_rcu(&event->rcu_head, free_event_rcu); free_event_rcu() perf_event_free_bpf_prog() To fix the race simply move perf_event_free_bpf_prog() before event->destroy(), since event->tp_event is still valid at that point. Note, perf_trace_destroy() is not racing with trace_remove_event_call() since they both grab event_mutex. Reported-by: Wang Nan <wangnan0@huawei.com> Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: lizefan@huawei.com Cc: pi3orama@163.com Fixes: 2541517c ("tracing, perf: Implement BPF programs attached to kprobes") Link: http://lkml.kernel.org/r/1431717321-28772-1-git-send-email-ast@plumgrid.comSigned-off-by: Ingo Molnar <mingo@kernel.org>
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- 25 May, 2015 1 commit
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Linus Torvalds authored
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- 24 May, 2015 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds authored
Pull SCSI fixes from James Bottomley: "This is a set of five fixes: Two MAINTAINER email updates (urgent because the non-avagotech emails will start bouncing) an lpfc big endian oops fix, a 256 byte sector hang fix (to eliminate 256 byte sectors) and a storvsc fix which could cause test unit ready failures on bringup" * tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: MAINTAINERS: Revise lpfc maintainers for Avago Technologies ownership of Emulex MAINTAINERS, be2iscsi: change email domain sd: Disable support for 256 byte/sector disks lpfc: Fix breakage on big endian kernels storvsc: Set the SRB flags correctly when no data transfer is needed
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull timer fix from Thomas Gleixner: "One more fix from the timer departement: - Handle division of negative nanosecond values proper on 32bit. A recent cleanup wrecked the sign handling of the dividend and dropped the check for negative divisors" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: ktime: Fix ktime_divns to do signed division
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipLinus Torvalds authored
Pull irqchip fix from Thomas Gleixner: "A fix for a GIC-V3 irqchip regression which prevents some systems from booting" * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqchip/gicv3-its: ITS table size should not be smaller than PSZ
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