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* Merge branch 'perf-fixes-for-linus' of ↵Linus Torvalds2009-12-19
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf session: Make events_stats u64 to avoid overflow on 32-bit arches hw-breakpoints: Fix hardware breakpoints -> perf events dependency perf events: Dont report side-band events on each cpu for per-task-per-cpu events perf events, x86/stacktrace: Fix performance/softlockup by providing a special frame pointer-only stack walker perf events, x86/stacktrace: Make stack walking optional perf events: Remove unused perf_counter.h header file perf probe: Check new event name kprobe-tracer: Check new event/group name perf probe: Check whether debugfs path is correct perf probe: Fix libdwarf include path for Debian
| * perf session: Make events_stats u64 to avoid overflow on 32-bit archesArnaldo Carvalho de Melo2009-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pekka Enberg reported weird percentages in perf report. It turns out we are overflowing a 32-bit variables in struct events_stats on 32-bit architectures. Before: [acme@ana linux-2.6-tip]$ perf report -i pekka.perf.data 2> /dev/null | head -10 281.96% Xorg b710a561 [.] 0x000000b710a561 140.15% Xorg [kernel] [k] __initramfs_end 51.56% metacity libgobject-2.0.so.0.2000.1 [.] 0x00000000026e46 35.12% evolution libcairo.so.2.10800.6 [.] 0x000000000203bd 33.84% metacity libpthread-2.9.so [.] 0x00000000007a3d After: [acme@ana linux-2.6-tip]$ perf report -i pekka.perf.data 2> /dev/null | head -10 30.04% Xorg b710a561 [.] 0x000000b710a561 14.93% Xorg [kernel] [k] __initramfs_end 5.49% metacity libgobject-2.0.so.0.2000.1 [.] 0x00000000026e46 3.74% evolution libcairo.so.2.10800.6 [.] 0x000000000203bd 3.61% metacity libpthread-2.9.so [.] 0x00000000007a3d Reported-by: Pekka Enberg <penberg@cs.helsinki.fi> Tested-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1261148583-20395-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * hw-breakpoints: Fix hardware breakpoints -> perf events dependencyFrederic Weisbecker2009-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The kbuild's select command doesn't propagate through the config dependencies. Hence the current rules of hardware breakpoint's config can't ensure perf can never be disabled under us. We have: config X86 selects HAVE_HW_BREAKPOINTS config HAVE_HW_BREAKPOINTS select PERF_EVENTS config PERF_EVENTS [...] x86 will select the breakpoints but that won't propagate to perf events. The user can still disable the latter, but it is necessary for the breakpoints. What we need is: - x86 selects HAVE_HW_BREAKPOINTS and PERF_EVENTS - HAVE_HW_BREAKPOINTS depends on PERF_EVENTS so that we ensure PERF_EVENTS is enabled and frozen for x86. This fixes the following kind of build errors: In file included from arch/x86/kernel/hw_breakpoint.c:31: include/linux/hw_breakpoint.h: In function 'hw_breakpoint_addr': include/linux/hw_breakpoint.h:39: error: 'struct perf_event' has no member named 'attr' v2: Select also ANON_INODES from x86, required for perf Reported-by: Cyrill Gorcunov <gorcunov@gmail.com> Reported-by: Michal Marek <mmarek@suse.cz> Reported-by: Andrew Randrianasulu <randrik_a@yahoo.com> Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Randy Dunlap <randy.dunlap@oracle.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> LKML-Reference: <1261010034-7786-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf events: Dont report side-band events on each cpu for per-task-per-cpu ↵Peter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | events Acme noticed that his FORK/MMAP numbers were inflated by about the same factor as his cpu-count. This led to the discovery of a few more sites that need to respect the event->cpu filter. Reported-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <20091217121830.215333434@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf events, x86/stacktrace: Fix performance/softlockup by providing a ↵Frederic Weisbecker2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | special frame pointer-only stack walker It's just wasteful for stacktrace users like perf to walk through every entries on the stack whereas these only accept reliable ones, ie: that the frame pointer validates. Since perf requires pure reliable stacktraces, it needs a stack walker based on frame pointers-only to optimize the stacktrace processing. This might solve some near-lockup scenarios that can be triggered by call-graph tracing timer events. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1261024834-5336-2-git-send-regression-fweisbec@gmail.com> [ v2: fix for modular builds and small detail tidyup ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf events, x86/stacktrace: Make stack walking optionalFrederic Weisbecker2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current print_context_stack helper that does the stack walking job is good for usual stacktraces as it walks through all the stack and reports even addresses that look unreliable, which is nice when we don't have frame pointers for example. But we have users like perf that only require reliable stacktraces, and those may want a more adapted stack walker, so lets make this function a callback in stacktrace_ops that users can tune for their needs. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <1261024834-5336-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf events: Remove unused perf_counter.h header fileRobert P. J. Day2009-12-17
| | | | | | | | | | | | | | | | | | | | | | Since nothing includes the <linux/perf_counter.h> file and it's also not exported to user space, remove it. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> LKML-Reference: <alpine.LFD.2.00.0912161007430.8198@localhost> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf probe: Check new event nameMasami Hiramatsu2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Check new event name is same syntax as a C symbol in perf command. In other words, checking the name is as like as other tracepoint events. This can prevent user to create an event with useless name (e.g. foo|bar, foo*bar). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091216222415.14459.71383.stgit@dhcp-100-2-132.bos.redhat.com> [ v2: minor cleanups ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * kprobe-tracer: Check new event/group nameMasami Hiramatsu2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Check new event/group name is same syntax as a C symbol. In other words, checking the name is as like as other tracepoint events. This can prevent user to create an event with useless name (e.g. foo|bar, foo*bar). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091216222408.14459.68790.stgit@dhcp-100-2-132.bos.redhat.com> [ v2: minor cleanups ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf probe: Check whether debugfs path is correctMasami Hiramatsu2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Check whether the debugfs path is correct before executing a command, because perf-probe depends on debugfs. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Jason Baron <jbaron@redhat.com> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091216222400.14459.48162.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * perf probe: Fix libdwarf include path for DebianMasami Hiramatsu2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fix libdwarf include path to fit debian-like systems too. Borislav Petkov reported: > even after installing libdwarf-dev on my debian box here, > make in tools/perf/ still complains that it cannot find libdwarf: > > Makefile:491: No libdwarf.h found or old libdwarf.h found, disables dwarf > support. Please install libdwarf-dev/libdwarf-devel >= 20081231 > > The problem is that the include path on debian is not > /usr/include/libdwarf/ but simply /usr/include because the debian > package libdwarf-dev puts the headers straight into > /usr/include. This patch adds -I/usr/include/libdwarf to BASIC_CFLAGS and fix probe-finder.h to include just libdwarf.h/dwarf.h. This patch also adds a workaround for the undefined _MIPS_SZLONG bug in libdwarf.h. Reported-by: Borislav Petkov <borislav.petkov@amd.com> Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Gabor Gombas <gombasg@sztaki.hu> Cc: systemtap <systemtap@sources.redhat.com> Cc: DLE <dle-develop@lists.sourceforge.net> LKML-Reference: <20091216221618.13816.83296.stgit@dhcp-100-2-132.bos.redhat.com> [ v2: small stylistic fixlets to probe-finder.h ] Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | Merge branch 'x86-fixes-for-linus' of ↵Linus Torvalds2009-12-19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system Makefile: Unexport LC_ALL instead of clearing it x86: Fix objdump version check in arch/x86/tools/chkobjdump.awk x86: Reenable TSC sync check at boot, even with NONSTOP_TSC x86: Don't use POSIX character classes in gen-insn-attr-x86.awk Makefile: set LC_CTYPE, LC_COLLATE, LC_NUMERIC to C x86: Increase MAX_EARLY_RES; insufficient on 32-bit NUMA x86: Fix checking of SRAT when node 0 ram is not from 0 x86, cpuid: Add "volatile" to asm in native_cpuid() x86, msr: msrs_alloc/free for CONFIG_SMP=n x86, amd: Get multi-node CPU info from NodeId MSR instead of PCI config space x86: Add IA32_TSC_AUX MSR and use it x86, msr/cpuid: Register enough minors for the MSR and CPUID drivers initramfs: add missing decompressor error check bzip2: Add missing checks for malloc returning NULL bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failure
| * | x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu systemSuresh Siddha2009-12-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | John Blackwood reported: > on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded), > and 32 bit (x86) kernel, once you change the irq smp_affinity of an irq > to be less than all cpus in the system, you can never change really the > irq smp_affinity back to be all cpus in the system (0xff) again, > even though no error status is returned on the "/bin/echo ff > > /proc/irq/[n]/smp_affinity" operation. > > This is due to that fact that BAD_APICID has the same value as > all cpus (0xff) on 32bit kernels, and thus the value returned from > set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated > as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes > are made. set_desc_affinity() is already checking if the incoming cpu mask intersects with the cpu online mask or not. So there is no need for the apic op cpu_mask_to_apicid_and() to check again and return BAD_APICID. Remove the BAD_APICID return value from cpu_mask_to_apicid_and() and also fix set_desc_affinity() to return -1 instead of using BAD_APICID to represent error conditions (as cpu_mask_to_apicid_and() can return logical or physical apicid values and BAD_APICID is really to represent bad physical apic id). Reported-by: John Blackwood <john.blackwood@ccur.com> Root-caused-by: John Blackwood <john.blackwood@ccur.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <1261103386.2535.409.camel@sbs-t61> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | Makefile: Unexport LC_ALL instead of clearing itH. Peter Anvin2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Apparently not all versions of glibc and utilities treat an empty LC_ALL as nonexistent, causing error messages to be garbled. Instead, explicitly unexport it from the environment. Reported-and-tested-by: Masami Hiramatsu <mhiramat@redhat.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <4B2AC394.4030108@redhat.com> Cc: Michal Marek <mmarek@sues.cz> Cc: Roland Dreier <rdreier@cisco.com> Cc: Sam Ravnborg <sam@ravnborg.org>
| * | x86: Fix objdump version check in arch/x86/tools/chkobjdump.awkakpm@linux-foundation.org2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It says Warning: objdump version is older than 2.19 Warning: Skipping posttest. because it used the wrong field from `objdump -v': akpm:/usr/src/25> /opt/crosstool/gcc-4.0.2-glibc-2.3.6/x86_64-unknown-linux-gnu/bin/x86_64-unknown-linux-gnu-objdump -v GNU objdump 2.16.1 Copyright 2005 Free Software Foundation, Inc. This program is free software; you may redistribute it under the terms of the GNU General Public License. This program has absolutely no warranty. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> LKML-Reference: <200912172326.nBHNQaQl024796@imap1.linux-foundation.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com> Cc: Masami Hiramatsu <mhiramat@redhat.com>
| * | x86: Reenable TSC sync check at boot, even with NONSTOP_TSCPallipadi, Venkatesh2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 83ce4009 did the following change If the TSC is constant and non-stop, also set it reliable. But, there seems to be few systems that will end up with TSC warp across sockets, depending on how the cpus come out of reset. Skipping TSC sync test on such systems may result in time inconsistency later. So, reenable TSC sync test even on constant and non-stop TSC systems. Set, sched_clock_stable to 1 by default and reset it in mark_tsc_unstable, if TSC sync fails. This change still gives perf benefit mentioned in 83ce4009 for systems where TSC is reliable. Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com> Acked-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <20091217202702.GA18015@linux-os.sc.intel.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86: Don't use POSIX character classes in gen-insn-attr-x86.awkRoland Dreier2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Not all awk implementations (including the default awk in Ubuntu 9.10) support POSIX character classes. Since x86-opcode-map.txt is plain ASCII, we can just use explicit ranges for lower case, alphabetic, and alphanumeric characters instead. Signed-off-by: Roland Dreier <rolandd@cisco.com> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> LKML-Reference: <adabphy750b.fsf@roland-alpha.cisco.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | Makefile: set LC_CTYPE, LC_COLLATE, LC_NUMERIC to CH. Peter Anvin2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are a number of common Unix constructs like character ranges in grep/sed/awk which don't work as expected with LC_COLLATE set to other than C. Similarly, set LC_CTYPE and LC_NUMERIC to C to avoid other nasty surprises. In order to make sure these actually take effect we also have to clear LC_ALL. Signed-off-by: H. Peter Anvin <hpa@zytor.com> Acked-by: Michal Marek <mmarek@sues.cz> Acked-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Roland Dreier <rdreier@cisco.com> Cc: Sam Ravnborg <sam@ravnborg.org> LKML-Reference: <4B2A1761.4070904@suse.cz>
| * | x86: Increase MAX_EARLY_RES; insufficient on 32-bit NUMAYinghai Lu2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | Due to recent changes wakeup and mptable, we run out of early reservations on 32-bit NUMA. Thus, adjust the available number. Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4B22D754.2020706@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86: Fix checking of SRAT when node 0 ram is not from 0Yinghai Lu2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Found one system that boot from socket1 instead of socket0, SRAT get rejected... [ 0.000000] SRAT: Node 1 PXM 0 0-a0000 [ 0.000000] SRAT: Node 1 PXM 0 100000-80000000 [ 0.000000] SRAT: Node 1 PXM 0 100000000-2080000000 [ 0.000000] SRAT: Node 0 PXM 1 2080000000-4080000000 [ 0.000000] SRAT: Node 2 PXM 2 4080000000-6080000000 [ 0.000000] SRAT: Node 3 PXM 3 6080000000-8080000000 [ 0.000000] SRAT: Node 4 PXM 4 8080000000-a080000000 [ 0.000000] SRAT: Node 5 PXM 5 a080000000-c080000000 [ 0.000000] SRAT: Node 6 PXM 6 c080000000-e080000000 [ 0.000000] SRAT: Node 7 PXM 7 e080000000-10080000000 ... [ 0.000000] NUMA: Allocated memnodemap from 500000 - 701040 [ 0.000000] NUMA: Using 20 for the hash shift. [ 0.000000] Adding active range (0, 0x2080000, 0x4080000) 0 entries of 3200 used [ 0.000000] Adding active range (1, 0x0, 0x96) 1 entries of 3200 used [ 0.000000] Adding active range (1, 0x100, 0x7f750) 2 entries of 3200 used [ 0.000000] Adding active range (1, 0x100000, 0x2080000) 3 entries of 3200 used [ 0.000000] Adding active range (2, 0x4080000, 0x6080000) 4 entries of 3200 used [ 0.000000] Adding active range (3, 0x6080000, 0x8080000) 5 entries of 3200 used [ 0.000000] Adding active range (4, 0x8080000, 0xa080000) 6 entries of 3200 used [ 0.000000] Adding active range (5, 0xa080000, 0xc080000) 7 entries of 3200 used [ 0.000000] Adding active range (6, 0xc080000, 0xe080000) 8 entries of 3200 used [ 0.000000] Adding active range (7, 0xe080000, 0x10080000) 9 entries of 3200 used [ 0.000000] SRAT: PXMs only cover 917504MB of your 1048566MB e820 RAM. Not used. [ 0.000000] SRAT: SRAT not used. the early_node_map is not sorted because node0 with non zero start come first. so try to sort it right away after all regions are registered. also fixs refression by 8716273c (x86: Export srat physical topology) -v2: make it more solid to handle cross node case like node0 [0,4g), [8,12g) and node1 [4g, 8g), [12g, 16g) -v3: update comments. Reported-and-tested-by: Jens Axboe <jens.axboe@oracle.com> Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <4B2579D2.3010201@kernel.org> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, cpuid: Add "volatile" to asm in native_cpuid()Suresh Siddha2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xsave_cntxt_init() does something like: cpuid(0xd, ..); // find out what features FP/SSE/.. etc are supported xsetbv(); // enable the features known to OS cpuid(0xd, ..); // find out the size of the context for features enabled Depending on what features get enabled in xsetbv(), value of the cpuid.eax=0xd.ecx=0.ebx changes correspondingly (representing the size of the context that is enabled). As we don't have volatile keyword for native_cpuid(), gcc 4.1.2 optimizes away the second cpuid and the kernel continues to use the cpuid information obtained before xsetbv(), ultimately leading to kernel crash on processors supporting more state than the legacy FP/SSE. Add "volatile" for native_cpuid(). Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> LKML-Reference: <1261009542.2745.55.camel@sbs-t61.sc.intel.com> Cc: stable@kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, msr: msrs_alloc/free for CONFIG_SMP=nBorislav Petkov2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Randy Dunlap reported the following build error: "When CONFIG_SMP=n, CONFIG_X86_MSR=m: ERROR: "msrs_free" [drivers/edac/amd64_edac_mod.ko] undefined! ERROR: "msrs_alloc" [drivers/edac/amd64_edac_mod.ko] undefined!" This is due to the fact that <arch/x86/lib/msr.c> is conditioned on CONFIG_SMP and in the UP case we have only the stubs in the header. Fork off SMP functionality into a new file (msr-smp.c) and build msrs_{alloc,free} unconditionally. Reported-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: H. Peter Anvin <hpa@zytor.com> Signed-off-by: Borislav Petkov <petkovbb@gmail.com> LKML-Reference: <20091216231625.GD27228@liondog.tnic> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86, amd: Get multi-node CPU info from NodeId MSR instead of PCI config spaceAndreas Herrmann2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | Use NodeId MSR to get NodeId and number of nodes per processor. Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com> LKML-Reference: <20091216144355.GB28798@alberich.amd.com> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | x86: Add IA32_TSC_AUX MSR and use itSheng Yang2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Clean up write_tsc() and write_tscp_aux() by replacing hardcoded values. No change in functionality. Signed-off-by: Sheng Yang <sheng@linux.intel.com> Cc: Avi Kivity <avi@redhat.com> Cc: Marcelo Tosatti <mtosatti@redhat.com> LKML-Reference: <1260942485-19156-4-git-send-email-sheng@linux.intel.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | x86, msr/cpuid: Register enough minors for the MSR and CPUID driversH. Peter Anvin2009-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | register_chrdev() hardcodes registering 256 minors, presumably to avoid breaking old drivers. However, we need to register enough minors so that we have all possible CPUs. checkpatch warns on this patch, but the patch is correct: NR_CPUS here is a static *upper bound* on the *maximum CPU index* (not *number of CPUs!*) and that is what we want. Reported-and-tested-by: Russ Anderson <rja@sgi.com> Cc: Tejun Heo <tj@kernel.org> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Takashi Iwai <tiwai@suse.de> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com> LKML-Reference: <tip-*@git.kernel.org>
| * | initramfs: add missing decompressor error checkPhillip Lougher2009-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The decompressors return error by calling a supplied error function, and/or by returning an error return value. The initramfs code, however, fails to check the exit code returned by the decompressor, and only checks the error status set by calling the error function. This patch adds a return code check and calls the error function. Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> LKML-Reference: <4b26b1ef.0+ZWxT6886olqcSc%phillip@lougher.demon.co.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | bzip2: Add missing checks for malloc returning NULLPhillip Lougher2009-12-15
| | | | | | | | | | | | | | | | | | Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> LKML-Reference: <4b26b1ef.ln20bM9Mn4gzB21L%phillip@lougher.demon.co.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
| * | bzip2/lzma/gzip: pre-boot malloc doesn't return NULL on failurePhillip Lougher2009-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The trivial malloc implementation used in the pre-boot environment by the decompressors returns a bad pointer on failure (falling through after calling error). This is doubly wrong - the callers expect malloc to return NULL on failure, second the error function is intended to be used by the decompressors to propagate errors to *their* callers. The decompressors have no access to any state set by the error function. Signed-off-by: Phillip Lougher <phillip@lougher.demon.co.uk> LKML-Reference: <4b26b1ef.hIInb2AYPMtImAJO%phillip@lougher.demon.co.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
* | | Merge branch 'sched-fixes-for-linus' of ↵Linus Torvalds2009-12-19
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits) sched: Fix broken assertion sched: Assert task state bits at build time sched: Update task_state_arraypwith new states sched: Add missing state chars to TASK_STATE_TO_CHAR_STR sched: Move TASK_STATE_TO_CHAR_STR near the TASK_state bits sched: Teach might_sleep() about preemptible RCU sched: Make warning less noisy sched: Simplify set_task_cpu() sched: Remove the cfs_rq dependency from set_task_cpu() sched: Add pre and post wakeup hooks sched: Move kthread_bind() back to kthread.c sched: Fix select_task_rq() vs hotplug issues sched: Fix sched_exec() balancing sched: Ensure set_task_cpu() is never called on blocked tasks sched: Use TASK_WAKING for fork wakups sched: Select_task_rq_fair() must honour SD_LOAD_BALANCE sched: Fix task_hot() test order sched: Fix set_cpu_active() in cpu_down() sched: Mark boot-cpu active before smp_init() sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCK ...
| * | | sched: Fix broken assertionPeter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's a preemption race in the set_task_cpu() debug check in that when we get preempted after setting task->state we'd still be on the rq proper, but fail the test. Check for preempted tasks, since those are always on the RQ. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121830.137155561@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Assert task state bits at build timePeter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since everybody is lazy and prone to forgetting things, make the compiler help us a bit. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121830.060186433@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Update task_state_arraypwith new statesPeter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Neglected because its hidden... (who reads comments anyway) Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121829.970166036@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Add missing state chars to TASK_STATE_TO_CHAR_STRPeter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We grew 3 new task states since the last time someone touched it. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121829.892737686@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Move TASK_STATE_TO_CHAR_STR near the TASK_state bitsPeter Zijlstra2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | So that we don't keep forgetting about it. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> LKML-Reference: <20091217121829.815779372@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Teach might_sleep() about preemptible RCUFrederic Weisbecker2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In practice, it is harmless to voluntarily sleep in a rcu_read_lock() section if we are running under preempt rcu, but it is illegal if we build a kernel running non-preemptable rcu. Currently, might_sleep() doesn't notice sleepable operations under rcu_read_lock() sections if we are running under preemptable rcu because preempt_count() is left untouched after rcu_read_lock() in this case. But we want developers who test their changes under such config to notice the "sleeping while atomic" issues. So we add rcu_read_lock_nesting to prempt_count() in might_sleep() checks. [ v2: Handle rcu-tiny ] Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> LKML-Reference: <1260991265-8451-1-git-send-regression-fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Make warning less noisyIngo Molnar2009-12-17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.807938893@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Simplify set_task_cpu()Peter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rearrange code a bit now that its a simpler function. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.269101883@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Remove the cfs_rq dependency from set_task_cpu()Peter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to remove the cfs_rq dependency from set_task_cpu() we need to ensure the task is cfs_rq invariant for all callsites. The simple approach is to substract cfs_rq->min_vruntime from se->vruntime on dequeue, and add cfs_rq->min_vruntime on enqueue. However, this has the downside of breaking FAIR_SLEEPERS since we loose the old vruntime as we only maintain the relative position. To solve this, we observe that we only migrate runnable tasks, we do this using deactivate_task(.sleep=0) and activate_task(.wakeup=0), therefore we can restrain the min_vruntime invariance to that state. The only other case is wakeup balancing, since we want to maintain the old vruntime we cannot make it relative on dequeue, but since we don't migrate inactive tasks, we can do so right before we activate it again. This is where we need the new pre-wakeup hook, we need to call this while still holding the old rq->lock. We could fold it into ->select_task_rq(), but since that has multiple callsites and would obfuscate the locking requirements, that seems like a fudge. This leaves the fork() case, simply make sure that ->task_fork() leaves the ->vruntime in a relative state. This covers all cases where set_task_cpu() gets called, and ensures it sees a relative vruntime. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.191697025@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Add pre and post wakeup hooksPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As will be apparent in the next patch, we need a pre wakeup hook for sched_fair task migration, hence rename the post wakeup hook and one pre wakeup. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.114746117@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Move kthread_bind() back to kthread.cPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since kthread_bind() lost its dependencies on sched.c, move it back where it came from. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170518.039524041@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix select_task_rq() vs hotplug issuesPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since select_task_rq() is now responsible for guaranteeing ->cpus_allowed and cpu_active_mask, we need to verify this. select_task_rq_rt() can blindly return smp_processor_id()/task_cpu() without checking the valid masks, select_task_rq_fair() can do the same in the rare case that all SD_flags are disabled. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.961475466@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix sched_exec() balancingPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since we access ->cpus_allowed without holding rq->lock we need a retry loop to validate the result, this comes for near free when we merge sched_migrate_task() into sched_exec() since that already does the needed check. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.884743662@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Ensure set_task_cpu() is never called on blocked tasksPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to clean up the set_task_cpu() rq dependencies we need to ensure it is never called on blocked tasks because such usage does not pair with consistent rq->lock usage. This puts the migration burden on ttwu(). Furthermore we need to close a race against changing ->cpus_allowed, since select_task_rq() runs with only preemption disabled. For sched_fork() this is safe because the child isn't in the tasklist yet, for wakeup we fix this by synchronizing set_cpus_allowed_ptr() against TASK_WAKING, which leaves sched_exec to be a problem This also closes a hole in (6ad4c1888 sched: Fix balance vs hotplug race) where ->select_task_rq() doesn't validate the result against the sched_domain/root_domain. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.807938893@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Use TASK_WAKING for fork wakupsPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For later convenience use TASK_WAKING for fresh tasks. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.732561278@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Select_task_rq_fair() must honour SD_LOAD_BALANCEPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We should skip !SD_LOAD_BALANCE domains. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.653578430@chello.nl> CC: stable@kernel.org Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix task_hot() test orderPeter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make sure not to access sched_fair fields before verifying it is indeed a sched_fair task. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> CC: stable@kernel.org LKML-Reference: <20091216170517.577998058@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Fix set_cpu_active() in cpu_down()Xiaotian Feng2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sachin found cpu hotplug test failures on powerpc, which made the kernel hang on his POWER box. The problem is that we fail to re-activate a cpu when a hot-unplug fails. Fix this by moving the de-activation into _cpu_down after doing the initial checks. Remove the synchronize_sched() calls and rely on those implied by rebuilding the sched domains using the new mask. Reported-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Tested-by: Sachin Sant <sachinp@in.ibm.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.500272612@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | sched: Mark boot-cpu active before smp_init()Peter Zijlstra2009-12-16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A UP machine has 1 active cpu, not having the boot-cpu in the active map when starting the scheduler confuses things. Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091216170517.423469527@chello.nl> Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | Merge branch 'linus' into sched/urgentIngo Molnar2009-12-16
| |\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Conflicts: kernel/sched_idletask.c Merge reason: resolve the conflicts, pick up latest changes. Signed-off-by: Ingo Molnar <mingo@elte.hu>
| * | | | sched: Fix cpu_clock() in NMIs, on !CONFIG_HAVE_UNSTABLE_SCHED_CLOCKDavid Miller2009-12-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Relax stable-sched-clock architectures to not save/disable/restore hardirqs in cpu_clock(). The background is that I was trying to resolve a sparc64 perf issue when I discovered this problem. On sparc64 I implement pseudo NMIs by simply running the kernel at IRQ level 14 when local_irq_disable() is called, this allows performance counter events to still come in at IRQ level 15. This doesn't work if any code in an NMI handler does local_irq_save() or local_irq_disable() since the "disable" will kick us back to cpu IRQ level 14 thus letting NMIs back in and we recurse. The only path which that does that in the perf event IRQ handling path is the code supporting frequency based events. It uses cpu_clock(). cpu_clock() simply invokes sched_clock() with IRQs disabled. And that's a fundamental bug all on it's own, particularly for the HAVE_UNSTABLE_SCHED_CLOCK case. NMIs can thus get into the sched_clock() code interrupting the local IRQ disable code sections of it. Furthermore, for the not-HAVE_UNSTABLE_SCHED_CLOCK case, the IRQ disabling done by cpu_clock() is just pure overhead and completely unnecessary. So the core problem is that sched_clock() is not NMI safe, but we are invoking it from NMI contexts in the perf events code (via cpu_clock()). A less important issue is the overhead of IRQ disabling when it isn't necessary in cpu_clock(). CONFIG_HAVE_UNSTABLE_SCHED_CLOCK architectures are not affected by this patch. Signed-off-by: David S. Miller <davem@davemloft.net> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Mike Galbraith <efault@gmx.de> LKML-Reference: <20091213.182502.215092085.davem@davemloft.net> Signed-off-by: Ingo Molnar <mingo@elte.hu>
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