- 24 Sep, 2014 7 commits
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Andi Kleen authored
On Broadwell INST_RETIRED.ALL cannot be used with any period that doesn't have the lowest 6 bits cleared. And the period should not be smaller than 128. Add a new callback to enforce this, and set it for Broadwell. This is erratum BDM57 and BDM11. How does this handle the case when an app requests a specific period with some of the bottom bits set The apps thinks it is sampling at X occurences per sample, when it is in fact at X - 63 (worst case). Short answer: Any useful instruction sampling period needs to be 4-6 orders of magnitude larger than 128, as an PMI every 128 instructions would instantly overwhelm the system and be throttled. So the +-64 error from this is really small compared to the period, much smaller than normal system jitter. Long answer: <write up by Peter:> IFF we guarantee perf_event_attr::sample_period >= 128. Suppose we start out with sample_period=192; then we'll set period_left to 192, we'll end up with left = 128 (we truncate the lower bits). We get an interrupt, find that period_left = 64 (>0 so we return 0 and don't get an overflow handler), up that to 128. Then we trigger again, at n=256. Then we find period_left = -64 (<=0 so we return 1 and do get an overflow). We increment with sample_period so we get left = 128. We fire again, at n=384, period_left = 0 (<=0 so we return 1 and get an overflow). And on and on. So while the individual interrupts are 'wrong' we get then with interval=256,128 in exactly the right ratio to average out at 192. And this works for everything >=128. So the num_samples*fixed_period thing is still entirely correct +- 127, which is good enough I'd say, as you already have that error anyhow. So no need to 'fix' the tools, al we need to do is refuse to create INST_RETIRED:ALL events with sample_period < 128. Signed-off-by:
Andi Kleen <ak@linux.intel.com> Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Maria Dimakopoulou <maria.n.dimakopoulou@gmail.com> Cc: Mark Davies <junk@eslaf.co.uk> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1409683455-29168-4-git-send-email-andi@firstfloor.orgSigned-off-by:
Ingo Molnar <mingo@kernel.org>
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Andi Kleen authored
Add Broadwell support for Broadwell Client to perf. This is very similar to Haswell. It uses a new cache event table, because there were various changes there. The constraint list has one new event that needs to be handled over Haswell. The PEBS event list is the same, so we reuse Haswell's. [fengguang.wu: make intel_bdw_event_constraints[] static] Signed-off-by:
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Andi Kleen authored
Add names for each Haswell model as requested by Peter. Signed-off-by:
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Andi Kleen authored
71 is a Broadwell, not a Haswell. The model number was added by mistake earlier. Remove it for now, until it can be re-added later with real Broadwell support. In practice it does not cause a lot of issues because the Broadwell PMU is very similar to Haswell, but some details were wrong, and it's better to handle it correctly. Signed-off-by:
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Jiri Olsa authored
This reverts commit 1f9a7268. With the fix of the initial state for the cloned event we now correctly handle the error described in: 1f9a7268 perf: Do not allow optimized switch for non-cloned events so we can revert it. I made an automated test for this, but its not suitable for automated perf tests framework. It needs to be customized for each machine (the more cpu the higher numbers for GROUPS/WORKERS/BYTES) and it could take longer time to hit the issue. Signed-off-by:
Jiri Olsa <jolsa@kernel.org> Signed-off-by:
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Jiri Olsa authored
Currently we initialize the child event based on the original parent state. This is wrong, because the original parent event (and its state) is not related to current fork and also could be already gone. We need to initialize the child state based on the immediate parent event state. Signed-off-by:
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Jiri Olsa authored
Currently we return POLLHUP in event polling if the monitored process is done, but we didn't consider possible children, that might be still running and producing data. Before returning POLLHUP making sure that: 1) the monitored task has exited and that 2) we don't have any children to monitor Also adding parent wakeup when the child event is gone. Suggested-by:
Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by:
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- 19 Sep, 2014 1 commit
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Ingo Molnar authored
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: o Add +field argument support for --sort option (Jiri Olsa) o Do not access kallsyms when analyzing user binaries with 'probe' (Masami Hiramatsu) o Ignore stripped vmlinux and fallback to kallsyms (Anton Blanchard) o Add path to Ubuntu kernel debuginfo file (Anton Blanchard) o Disable kernel symbol demangling by default (Avi Kivity) Infrastructure changes: o More intel PT prep work, from Adrian Hunter, including: - Let a user specify a PMU event without any config terms - Add perf-with-kcore script - Let default config be defined for a PMU - Add perf_pmu__scan_file() o "perf kvm stat report" improvements by Alexander Yarygin: o Save pid string in opts.target.pid o Enable the target.system_wide flag o Unify the title bar output o Fix build issue on powerpc when DWARF support is disabled (Anton Blanchard) o Allow to specify lib compile variable for spec usage (Jiri Olsa) o Fix build on ARM (Stephane Eranian) o Fix build on powerpc when DWARF support is disabled (Anton Blanchard) o Don't include sys/poll.h directly (Arnaldo Carvalho de Melo) o Use ring buffer consume method to look like other tools (Arnaldo Carvalho de Melo) o Allow to specify lib compile variable for spec usage (Jiri Olsa) o Fix GNU-only grep usage in Makefile (John Spencer) Signed-off-by:
Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by:
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- 17 Sep, 2014 20 commits
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Arnaldo Carvalho de Melo authored
All builtins that consume events from perf's ring buffer now end up calling perf_evlist__mmap_consume(), which will allow unmapping the ring buffer when all the fds gets closed and all events in the buffer consumed. This is in preparation for the patchkit that will notice POLLHUP on perf events file descriptors. Cc: Adrian Hunter <adrian.hunter@intel.com> 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: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/n/tip-8vhaeeoq11ppz0713el4xcps@git.kernel.orgSigned-off-by:
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Masami Hiramatsu authored
Do not use dwfl_module_addrsym if dwarf_diename can find the symbol name, since dwfl_module_addrsym can be failed on shared libraries. Without this patch ---- $ perf probe -x ../lib/traceevent/libtraceevent.so -V create_arg_op Failed to find symbol at 0x11df1 Failed to find the address of create_arg_op Error: Failed to show vars. ---- With this patch ---- $ perf probe -x ../lib/traceevent/libtraceevent.so -V create_arg_op Available variables at create_arg_op @<create_arg_op+0> enum filter_op_type btype struct filter_arg* arg ---- This bug was reported on linux-perf-users@vger.kernel.org. Reported-by:david lerner <dlernerdroid@gmail.com> Signed-off-by:
Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: david lerner <dlernerdroid@gmail.com> Cc: linux-perf-user@vger.kernel.org Cc: yrl.pp-manager.tt@hitachi.com Link: http://permalink.gmane.org/gmane.linux.kernel.perf.user/1691 Link: http://lkml.kernel.org/r/20140917084101.3722.25299.stgit@kbuild-f20.novalocalSigned-off-by:
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Masami Hiramatsu authored
Do not access kallsyms to show available variables and show source lines in user binaries. This behavior always requires the root privilege when sysctl sets kernel.kptr_restrict=1, but we don't need it just for analyzing user binaries. Without this patch (by normal user, kptr_restrict=1): ---- $ perf probe -x ./perf -V add_cmdname Failed to init vmlinux path. Error: Failed to show vars. $ perf probe -x ./perf -L add_cmdname Failed to init vmlinux path. Error: Failed to show lines. ---- With this patch: ---- $ perf probe -x ./perf -V add_cmdname Available variables at add_cmdname @<perf_unknown_cmd_config+144> (No matched variables) @<list_commands_in_dir+160> (No matched variables) @<add_cmdname+0> char* name size_t len struct cmdnames* cmds $ perf probe -x ./perf -L add_cmdname <add_cmdname@/home/fedora/ksrc/linux-3/tools/perf/util/help.c:0> 0 void add_cmdname(struct cmdnames *cmds, const char *name, size_t len) 1 { 2 struct cmdname *ent = malloc(sizeof(*ent) + len + 1); 4 ent->len = len; 5 memcpy(ent->name, name, len); 6 ent->name[len] = 0; ... ---- Signed-off-by: -
Anton Blanchard authored
Ubuntu places the kernel debuginfo in /usr/lib/debug/boot/vmlinux-* Signed-off-by:
Anton Blanchard <anton@samba.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> echo Link: http://lkml.kernel.org/n/tip-`ranpwd -l 24`@git.kernel.org Link: http://lkml.kernel.org/r/20140909091152.2698c0f7@kryten [ Adapted it to use the perf.data file kernel version as in 0a7e6d1b ] Signed-off-by:
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Anton Blanchard authored
If a vmlinux is stripped, perf will use it and ignore kallsyms. We end up with useless profiles where everything maps to a few runtime symbols: 63.39% swapper [kernel.kallsyms] [k] hcall_real_table 4.90% beam.smp [kernel.kallsyms] [k] hcall_real_table 4.44% beam.smp [kernel.kallsyms] [k] __sched_text_start 3.72% beam.smp [kernel.kallsyms] [k] __run_at_kexec Detect this case and fallback to using kallsyms. This fixes the issue: 62.81% swapper [kernel.kallsyms] [k] snooze_loop 4.44% beam.smp [kernel.kallsyms] [k] __schedule 0.91% beam.smp [kernel.kallsyms] [k] _switch 0.73% beam.smp [kernel.kallsyms] [k] put_prev_entity Signed-off-by:Namhyung Kim <namhyung@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20140909085929.4a5a81f0@krytenSigned-off-by:
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Chanho Park authored
_BSD_SOURCE was deprecated in favour of _DEFAULT_SOURCE since glibc 2.20[1]. To avoid build warning on glibc2.20, _DEFAULT_SOURCE should also be defined. [1]: https://sourceware.org/glibc/wiki/Release/2.20Signed-off-by:
Chanho Park <chanho61.park@samsung.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1410487817-13403-1-git-send-email-chanho61.park@samsung.comSigned-off-by:
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Arnaldo Carvalho de Melo authored
Include poll.h instead. Fixes the following warning in systems with musl's libc: /usr/include/sys/poll.h:1:2: warning: #warning redirecting incorrect #include <sys/poll.h> to <poll.h> [-Wcpp] Reported-by:
John Spencer <maillist-linux@barfooze.de> Cc: Adrian Hunter <adrian.hunter@intel.com> 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: Mike Galbraith <efault@gmx.de> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://thread.gmane.org/gmane.linux.kernel.perf.user/1687/focus=1690 Link: http://lkml.kernel.org/n/tip-k4ocrq1de3fk146oevy346bi@git.kernel.orgSigned-off-by:
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John Spencer authored
This makes it work with non-GNU grep's as well. Signed-off-by:
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Avi Kivity authored
Some Linux symbols (for example __vt_event_wait) are interpreted by the demangler as C++ mangled names, which of course they aren't. Disable kernel symbol demangling by default to avoid this, and allow enabling it with a new option --demangle-kernel for those who wish it. Reported-by:
Jiri Olsa <jolsa@redhat.com> Signed-off-by:
Avi Kivity <avi@cloudius-systems.com> Acked-by:
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Stephane Eranian authored
This patch fixes ARM compile of the perf tool. The debug.h header file was missing from a couple of unwind related modules. Signed-off-by:
Stephane Eranian <eranian@google.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20140905042103.GA3091@quadSigned-off-by:
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Adrian Hunter authored
Add a function to scan a sysfs file within the pmu device directory. This will be used to read capability values from the PMU 'caps' subdirectory. Signed-off-by:
Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Namhyung Kim <namhyung@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Link: http://lkml.kernel.org/r/1406786474-9306-8-git-send-email-adrian.hunter@intel.comSigned-off-by:
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Adrian Hunter authored
This allows default config terms to be provided for a PMU. So, for example, when the Intel PT PMU is added, it will be possible to specify: intel_pt// which will be the same as: intel_pt/tsc=1,noretcomp=0/ meaning that the trace should contain TSC timestamps and perform 'return compression'. An important consideration of this patch is that it must be possible to overwrite the default values. That has meant changing the logic so that a zero value can replace a non-zero value. Signed-off-by:
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Adrian Hunter authored
Decoding an Intel PT trace of the kernel requires an accurate kernel object image. This is provided by making a copy of kcore. However the copy needs to be made under the same conditions as the original recording, and then it needs to be associated with the perf.data file. The perf-with-kcore script does that. The script also checks the permissions on the buildid cache and can be used to fix them. That is needed for distributions where root does not have a home directory and consequently writes to the same buildid cache as the user, resulting in cached files that the user does not have access to. Example: $ ./perf-with-kcore Usage: perf-with-kcore <perf sub-command> <perf.data directory> [<sub-command options> [ -- <workload>]] <perf sub-command> can be record, script, report or inject or: perf-with-kcore fix_buildid_cache_permissions $ ./perf-with-kcore record pt_uname -e intel_pt// -- uname Recording Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf record -o pt_uname/perf.data -e intel_pt// -- uname Linux [ perf record: Woken up 3 times to write data ] [ perf record: Captured and wrote 0.023 MB pt_uname/perf.data ] Copying kcore [sudo] password for ahunter: Done $ tools/perf/perf-with-kcore.sh script pt_uname | head Using /home/ahunter/bin/perf perf version 3.15.rc3.g4549ba /home/ahunter/bin/perf script -i pt_uname/perf.data --kallsyms=pt_uname/kcore_dir/kallsyms swapper 0 [002] 161533.969666: sched:sched_switch: swapper/2:0 [120] R ==> perf:11316 [120] :11315 11315 [003] 161533.969704: sched:sched_switch: perf:11315 [120] S ==> swapper/3:0 [120] :11316 11316 [002] 161533.969783: sched:sched_switch: perf:11316 [120] R ==> migration/2:33 [0] :33 33 [002] 161533.969791: sched:sched_switch: migration/2:33 [0] S ==> swapper/2:0 [120] swapper 0 [003] 161533.969792: sched:sched_switch: swapper/3:0 [120] R ==> perf:11316 [120] :11316 11316 [003] 161533.970062: branches: 0 [unknown] ([unknown]) => ffffffff810532fa native_write_msr_safe ([kernel.kallsyms]) :11316 11316 [003] 161533.970062: branches: ffffffff810532fd native_write_msr_safe ([kernel.kallsyms]) => ffffffff81035b31 pt_config_start ([kernel.kallsyms]) Signed-off-by: -
Adrian Hunter authored
This enables a PMU event to be specified in the form: pmu// which is effectively the same as: pmu/config=0/ This patch is a precursor to defining default config for a PMU. Further explanation extracted from lkml thread: Imagine that the 'tsc' term did not exist. Intel PT trace data would not contain TSC packets, and the decoder would not know how to decode them. Then imagine that a new version of the hardware adds 'tsc'. It is such a useful feature that we want it by default, but older versions of the tools don't know how to decode it, so the kernel cannot turn it on by default. It is similar to why the kernel does not select perf_event_attr.mmap2 by default. The kernel doesn't know whether the tool supports it. Signed-off-by:
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Jiri Olsa authored
We need a way to specify $(lib) part of the installation path for traceevent plugin libraries. Currently we use 'lib64' for x86_64 and 'lib' otherwise. Instead of listing all possible values, this change allows the rpm spec code to specify the correct $(lib) part based on processed architecture, like $ make ... lib=%{_lib} Signed-off-by:Kyle McMartin <kyle@mcmartin.ca> Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1408978552-17131-1-git-send-email-jolsa@kernel.orgSigned-off-by:
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Alexander Yarygin authored
The 'live' command prints additional information to the "Analyze events for " title bar about the current target. Let's print the same title for the 'report' command. Signed-off-by:
Alexander Yarygin <yarygin@linux.vnet.ibm.com> Acked-by:
David Ahern <dsahern@gmail.com> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: David Ahern <dsahern@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/1409579095-12963-4-git-send-email-yarygin@linux.vnet.ibm.comSigned-off-by:
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Alexander Yarygin authored
The 'perf kvm stat report' command can be used to analyze events either for system wide or for specific pids. Let's enable kvm->opts.target.system_wide flag when 'report' command is running for system-wide analyzing. This helps to sync kvm->opts.target values in 'report' and 'live' commands. Signed-off-by:
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Alexander Yarygin authored
The 'perf kvm stat report' command uses the kvm->pid_str field to keep the value of the --pid option. Let's use kvm->opts.target.pid instead. Signed-off-by:
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Anton Blanchard authored
The powerpc skip callchain code uses DWARF, so we must disable it if DWARF is disabled. Signed-off-by:
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Jiri Olsa authored
Adding support to add field(s) to default sort order via using the '+' prefix, like for report: $ perf report Samples: 2K of event 'cycles', Event count (approx.): 882172583 Overhead Command Shared Object Symbol 7.39% swapper [kernel.kallsyms] [k] intel_idle 1.97% firefox libpthread-2.17.so [.] pthread_mutex_lock 1.39% firefox [snd_hda_intel] [k] azx_get_position 1.11% firefox libpthread-2.17.so [.] pthread_mutex_unlock $ perf report -s +cpu Samples: 2K of event 'cycles', Event count (approx.): 882172583 Overhead Command Shared Object Symbol CPU 2.89% swapper [kernel.kallsyms] [k] intel_idle 000 2.61% swapper [kernel.kallsyms] [k] intel_idle 002 1.20% swapper [kernel.kallsyms] [k] intel_idle 001 0.82% firefox libpthread-2.17.so [.] pthread_mutex_lock 002 Works in general for commands using --sort option. v2 with changes suggested: - Use dynamic memory instead static buffer - Fix error message typo Signed-off-by:
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- 16 Sep, 2014 1 commit
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Jiri Olsa authored
Revert PERF_EVENT_STATE_EXIT check on read syscall path. It breaks standard way to read counter, which is to open the counter, wait for the monitored process to die and read the counter. Reported-by:
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- 09 Sep, 2014 5 commits
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Andi Kleen authored
The new split Intel uncore driver code that recently went into tip added a section mismatch, which the build process complains about. uncore_pmu_register() can be called from uncore_pci_probe,() which is not __init and can be called from pci driver ->probe. I'm not fully sure if it's actually possible to call the probe function later, but it seems safer to mark uncore_pmu_register not __init. This also fixes the warning. Signed-off-by:
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Mathias Krause authored
A few of the initialization functions are missing the __init annotation. Fix this and thereby allow ~680 additional bytes of code to be released after initialization. Signed-off-by:
Mathias Krause <minipli@googlemail.com> Signed-off-by:
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Andreea-Cristina Bernat authored
The use of "rcu_assign_pointer()" is NULLing out the pointer. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Signed-off-by:Andreea-Cristina Bernat <bernat.ada@gmail.com> Signed-off-by:
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Andreea-Cristina Bernat authored
The use of "rcu_assign_pointer()" is NULLing out the pointer. According to RCU_INIT_POINTER()'s block comment: "1. This use of RCU_INIT_POINTER() is NULLing out the pointer" it is better to use it instead of rcu_assign_pointer() because it has a smaller overhead. The following Coccinelle semantic patch was used: @@ @@ - rcu_assign_pointer + RCU_INIT_POINTER (..., NULL) Signed-off-by:
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Ingo Molnar authored
Signed-off-by:
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- 07 Sep, 2014 6 commits
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Linus Torvalds authored
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Sudip Mukherjee authored
new link for - How to piss off a Linux kernel subsystem maintainer Signed-off-by:
Sudip Mukherjee <sudip@vectorindia.org> Signed-off-by:
Randy Dunlap <rdunlap@infradead.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org>
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Paul Bolle authored
The NFS/RDMA Kconfig symbol was split into separate options for client and server in commit 2e8c12e1 ("xprtrdma: add separate Kconfig options for NFSoRDMA client and server support"). Update the documentation to reflect this split. Signed-off-by:
Paul Bolle <pebolle@tiscali.nl> Reviewed-by:
Jeff Layton <jlayton@redhat.com> Signed-off-by:
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Masanari Iida authored
hpfall.c was renamed to freefall.c in 3.16, but this file still refer to hpfall.c instead of freefall.c Signed-off-by:
Masanari Iida <standby24x7@gmail.com> Signed-off-by:
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Jose Manuel Alarcon Roldan authored
The example code provided with the i2c device interface documentation won't compile since it uses the reserved word "register" to name a variable. The compiler fails with this error message: error: expected identifier or '(' before '=' token __u8 register = 0x20; /* Device register to access */ ^ Rename the variable "register" to simply "reg" in the example code. Another couple of typos has been fixed as well. [Change "! =" to "!=".] Signed-off-by:Jose Alarcon Roldan <jose.alarcon.roldan@gmail.com> Signed-off-by:
Wolfram Sang <wsa@the-dreams.de> Signed-off-by:
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Rob Jones authored
Despite the fact that these functions have been around for years, they are little used (only 15 uses in 13 files at the preseht time) even though many other files use work-arounds to achieve the same result. By documenting them, hopefully they will become more widely used. Signed-off-by:
Rob Jones <rob.jones@codethink.co.uk> Acked-by:
Steven Whitehouse <swhiteho@redhat.com> Signed-off-by:
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