summaryrefslogtreecommitdiffstats
path: root/kernel/debug
Commit message (Collapse)AuthorAgeFilesLines
* mm: per-thread vma cachingDavidlohr Bueso2014-04-071-3/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch is a continuation of efforts trying to optimize find_vma(), avoiding potentially expensive rbtree walks to locate a vma upon faults. The original approach (https://lkml.org/lkml/2013/11/1/410), where the largest vma was also cached, ended up being too specific and random, thus further comparison with other approaches were needed. There are two things to consider when dealing with this, the cache hit rate and the latency of find_vma(). Improving the hit-rate does not necessarily translate in finding the vma any faster, as the overhead of any fancy caching schemes can be too high to consider. We currently cache the last used vma for the whole address space, which provides a nice optimization, reducing the total cycles in find_vma() by up to 250%, for workloads with good locality. On the other hand, this simple scheme is pretty much useless for workloads with poor locality. Analyzing ebizzy runs shows that, no matter how many threads are running, the mmap_cache hit rate is less than 2%, and in many situations below 1%. The proposed approach is to replace this scheme with a small per-thread cache, maximizing hit rates at a very low maintenance cost. Invalidations are performed by simply bumping up a 32-bit sequence number. The only expensive operation is in the rare case of a seq number overflow, where all caches that share the same address space are flushed. Upon a miss, the proposed replacement policy is based on the page number that contains the virtual address in question. Concretely, the following results are seen on an 80 core, 8 socket x86-64 box: 1) System bootup: Most programs are single threaded, so the per-thread scheme does improve ~50% hit rate by just adding a few more slots to the cache. +----------------+----------+------------------+ | caching scheme | hit-rate | cycles (billion) | +----------------+----------+------------------+ | baseline | 50.61% | 19.90 | | patched | 73.45% | 13.58 | +----------------+----------+------------------+ 2) Kernel build: This one is already pretty good with the current approach as we're dealing with good locality. +----------------+----------+------------------+ | caching scheme | hit-rate | cycles (billion) | +----------------+----------+------------------+ | baseline | 75.28% | 11.03 | | patched | 88.09% | 9.31 | +----------------+----------+------------------+ 3) Oracle 11g Data Mining (4k pages): Similar to the kernel build workload. +----------------+----------+------------------+ | caching scheme | hit-rate | cycles (billion) | +----------------+----------+------------------+ | baseline | 70.66% | 17.14 | | patched | 91.15% | 12.57 | +----------------+----------+------------------+ 4) Ebizzy: There's a fair amount of variation from run to run, but this approach always shows nearly perfect hit rates, while baseline is just about non-existent. The amounts of cycles can fluctuate between anywhere from ~60 to ~116 for the baseline scheme, but this approach reduces it considerably. For instance, with 80 threads: +----------------+----------+------------------+ | caching scheme | hit-rate | cycles (billion) | +----------------+----------+------------------+ | baseline | 1.06% | 91.54 | | patched | 99.97% | 14.18 | +----------------+----------+------------------+ [akpm@linux-foundation.org: fix nommu build, per Davidlohr] [akpm@linux-foundation.org: document vmacache_valid() logic] [akpm@linux-foundation.org: attempt to untangle header files] [akpm@linux-foundation.org: add vmacache_find() BUG_ON] [hughd@google.com: add vmacache_valid_mm() (from Oleg)] [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: adjust and enhance comments] Signed-off-by: Davidlohr Bueso <davidlohr@hp.com> Reviewed-by: Rik van Riel <riel@redhat.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: Michel Lespinasse <walken@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Tested-by: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* KGDB: make kgdb_breakpoint() as noinlineVijaya Kumar K2014-02-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | The function kgdb_breakpoint() sets up break point at compile time by calling arch_kgdb_breakpoint(); Though this call is surrounded by wmb() barrier, the compile can still re-order the break point, because this scheduling barrier is not a code motion barrier in gcc. Making kgdb_breakpoint() as noinline solves this problem of code reording around break point instruction and also avoids problem of being called as inline function from other places More details about discussion on this can be found here http://comments.gmane.org/gmane.linux.ports.arm.kernel/269732 Signed-off-by: Vijaya Kumar K <Vijaya.Kumar@caviumnetworks.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
* kgdb/kdb: Fix no KDB config problemMike Travis2014-01-252-4/+3
| | | | | | | | | | | | | | | | | | | Some code added to the debug_core module had KDB dependencies that it shouldn't have. Move the KDB dependent REASON back to the caller to remove the dependency in the debug core code. Update the call from the UV NMI handler to conform to the new interface. Signed-off-by: Mike Travis <travis@sgi.com> Reviewed-by: Hedi Berriche <hedi@sgi.com> Cc: Russ Anderson <rja@sgi.com> Cc: Jason Wessel <jason.wessel@windriver.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Link: http://lkml.kernel.org/r/20140114162551.318251993@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* kdb: Add support for external NMI handler to call KGDB/KDBMike Travis2013-10-034-3/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds a kgdb_nmicallin() interface that can be used by external NMI handlers to call the KGDB/KDB handler. The primary need for this is for those types of NMI interrupts where all the CPUs have already received the NMI signal. Therefore no send_IPI(NMI) is required, and in fact it will cause a 2nd unhandled NMI to occur. This generates the "Dazed and Confuzed" messages. Since all the CPUs are getting the NMI at roughly the same time, it's not guaranteed that the first CPU that hits the NMI handler will manage to enter KGDB and set the dbg_master_lock before the slaves start entering. The new argument "send_ready" was added for KGDB to signal the NMI handler to release the slave CPUs for entry into KGDB. Signed-off-by: Mike Travis <travis@sgi.com> Acked-by: Jason Wessel <jason.wessel@windriver.com> Reviewed-by: Dimitri Sivanich <sivanich@sgi.com> Reviewed-by: Hedi Berriche <hedi@sgi.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Paul Mackerras <paulus@samba.org> Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net> Link: http://lkml.kernel.org/r/20131002151417.928886849@asylum.americas.sgi.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
* kgdb/sysrq: fix inconstistent help message of sysrq keyzhangwei(Jovi)2013-04-301-1/+1
| | | | | | | | | | | | | | | | | | | | | Currently help message of /proc/sysrq-trigger highlight its upper-case characters, like below: SysRq : HELP : loglevel(0-9) reBoot Crash terminate-all-tasks(E) memory-full-oom-kill(F) kill-all-tasks(I) ... this would confuse user trigger sysrq by upper-case character, which is inconsistent with the real lower-case character registed key. This inconsistent help message will also lead more confused when 26 upper-case letters put into use in future. This patch fix kgdb sysrq key: "debug(g)" Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'for_linux-3.9' of ↵Linus Torvalds2013-03-026-127/+62
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull KGDB/KDB fixes and cleanups from Jason Wessel: "For a change we removed more code than we added. If people aren't using it we shouldn't be carrying it. :-) Cleanups: - Remove kdb ssb command - there is no in kernel disassembler to support it - Remove kdb ll command - Always caused a kernel oops and there were no bug reports so no one was using this command - Use kernel ARRAY_SIZE macro instead of array computations Fixes: - Stop oops in kdb if user executes kdb_defcmd with args - kdb help command truncated text - ppc64 support for kgdbts - Add missing kconfig option from original kdb port for dealing with catastrophic kernel crashes such that you can reboot automatically on continue from kdb" * tag 'for_linux-3.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: kdb: Remove unhandled ssb command kdb: Prevent kernel oops with kdb_defcmd kdb: Remove the ll command kdb_main: fix help print kdb: Fix overlap in buffers with strcpy Fixed dead ifdef block by adding missing Kconfig option. kdb: Setup basic kdb state before invoking commands via kgdb kdb: use ARRAY_SIZE where possible kgdb/kgdbts: support ppc64 kdb: A fix for kdb command table expansion
| * kdb: Remove unhandled ssb commandVincent2013-03-024-39/+2
| | | | | | | | | | | | | | | | The 'ssb' command can only be handled when we have a disassembler, to check for branches, so remove the 'ssb' command for now. Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Prevent kernel oops with kdb_defcmdJason Wessel2013-03-021-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | The kdb_defcmd can only be used to display the available command aliases while using the kernel debug shell. If you try to define a new macro while the kernel debugger is active it will oops. The debug shell macros must use pre-allocated memory set aside at the time kdb_init() is run, and the kdb_defcmd is restricted to only working at the time that the kdb_init sequence is being run, which only occurs if you actually activate the kernel debugger. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Remove the ll commandJason Wessel2013-03-021-65/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | Recently some code inspection was done after fixing a problem with kmalloc used while in the kernel debugger context (which is not legal), and it turned up the fact that kdb ll command will oops the kernel. Given that there have been zero bug reports on the command combined with the fact it will oops the kernel it is clearly not being used. Instead of fixing it, it will be removed. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb_main: fix help printJason Wessel2013-03-021-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The help command was chopping all the usage instructions such that they were not readable. Example: bta [D|R|S|T|C|Z|E|U|I| Backtrace all processes matching state flag per_cpu <sym> [<bytes>] [<c Display per_cpu variables Where as it should look like: bta [D|R|S|T|C|Z|E|U|I|M|A] Backtrace all processes matching state flag per_cpu <sym> [<bytes>] [<cpu>] Display per_cpu variables All that is needed is to check the how long the cmd_usage is and jump to the next line when appropriate. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Fix overlap in buffers with strcpyJason Wessel2013-03-021-9/+21
| | | | | | | | | | | | | | | | | | | | | | Maxime reported that strcpy(s->usage, s->usage+1) has no definitive guarantee that it will work on all archs the same way when you have overlapping memory. The fix is simple for the kdb code because we still have the original string memory in the function scope, so we just have to use that as the argument instead. Reported-by: Maxime Villard <rustyBSD@gmx.fr> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Setup basic kdb state before invoking commands via kgdbMatt Klein2013-03-023-6/+23
| | | | | | | | | | | | | | | | | | | | Although invasive kdb commands are not supported via kgdb, some useful non-invasive commands like bt* require basic kdb state to be setup before calling into the kdb code. Factor out some of this code and call it before and after executing kdb commands via kgdb. Signed-off-by: Matt Klein <mklein@twitter.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: use ARRAY_SIZE where possibleSasha Levin2013-03-021-2/+2
| | | | | | | | | | Signed-off-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: A fix for kdb command table expansionJohn Blackwood2013-03-021-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When locally adding in some additional kdb commands, I stumbled across an issue with the dynamic expansion of the kdb command table. When the number of kdb commands exceeds the size of the statically allocated kdb_base_commands[] array, additional space is allocated in the kdb_register_repeat() routine. The unused portion of the newly allocated array was not being initialized to zero properly and this would result in segfaults when help '?' was executed or when a search for a non-existing command would traverse the command table beyond the end of valid command entries and then attempt to use the non-zeroed area as actual command entries. Signed-off-by: John Blackwood <john.blackwood@ccur.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | kgdb: remove #include <linux/serial_8250.h> from kgdb.hGreg Kroah-Hartman2013-02-042-0/+2
|/ | | | | | | | | There's no reason kgdb.h itself needs to include the 8250 serial port header file. So push it down to the _very_ limited number of individual drivers that need the values in that file, and fix up the places where people really wanted serial_core.h and platform_device.h. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* module: add new state MODULE_STATE_UNFORMED.Rusty Russell2013-01-121-0/+2
| | | | | | | | | You should never look at such a module, so it's excised from all paths which traverse the modules list. We add the state at the end, to avoid gratuitous ABI break (ksplice). Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* Merge tag 'for_linus-3.7' of ↵Linus Torvalds2012-10-134-5/+50
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull KGDB/KDB fixes and cleanups from Jason Wessel: "Cleanups - Clean up compile warnings in kgdboc.c and x86/kernel/kgdb.c - Add module event hooks for simplified debugging with gdb Fixes - Fix kdb to stop paging with 'q' on bta and dmesg - Fix for data that scrolls off the vga console due to line wrapping when using the kdb pager New - The debug core registers for kernel module events which allows a kernel aware gdb to automatically load symbols and break on entry to a kernel module - Allow kgdboc=kdb to setup kdb on the vga console" * tag 'for_linus-3.7' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: tty/console: fix warnings in drivers/tty/serial/kgdboc.c kdb,vt_console: Fix missed data due to pager overruns kdb: Fix dmesg/bta scroll to quit with 'q' kgdboc: Accept either kbd or kdb to activate the vga + keyboard kdb shell kgdb,x86: fix warning about unused variable mips,kgdb: fix recursive page fault with CONFIG_KPROBES kgdb: Add module event hooks
| * kdb,vt_console: Fix missed data due to pager overrunsJason Wessel2012-10-121-5/+28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | It is possible to miss data when using the kdb pager. The kdb pager does not pay attention to the maximum column constraint of the screen or serial terminal. This result is not incrementing the shown lines correctly and the pager will print more lines that fit on the screen. Obviously that is less than useful when using a VGA console where you cannot scroll back. The pager will now look at the kdb_buffer string to see how many characters are printed. It might not be perfect considering you can output ASCII that might move the cursor position, but it is a substantially better approximation for viewing dmesg and trace logs. This also means that the vt screen needs to set the kdb COLUMNS variable. Cc: <stable@vger.kernel.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Fix dmesg/bta scroll to quit with 'q'Jason Wessel2012-10-122-0/+4
| | | | | | | | | | | | | | | | | | If you press 'q' the pager should exit instead of printing everything from dmesg which can really bog down a 9600 baud serial link. The same is true for the bta command. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kgdb: Add module event hooksJason Wessel2012-10-121-0/+18
| | | | | | | | | | | | | | | | Allow gdb to auto load kernel modules when it is attached, which makes it trivially easy to debug module init functions or pre-set breakpoints in a kernel module that has not loaded yet. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | kdb: Implement disable_nmi commandAnton Vorontsov2012-09-261-0/+31
| | | | | | | | | | | | | | | | | | | | | | | | | | | | This command disables NMI-entry. If NMI source has been previously shared with a serial console ("debug port"), this effectively releases the port from KDB exclusive use, and makes the console available for normal use. Of course, NMI can be reenabled, enable_nmi modparam is used for that: echo 1 > /sys/module/kdb/parameters/enable_nmi Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* | kernel/debug: Mask KGDB NMI upon entryAnton Vorontsov2012-09-261-3/+11
|/ | | | | | | | | | | | | | The new arch callback should manage NMIs that usually cause KGDB to enter. That is, not all NMIs should be enabled/disabled, but only those that issue kgdb_handle_exception(). We must mask it as serial-line interrupt can be used as an NMI, so if the original KGDB-entry cause was say a breakpoint, then every input to KDB console will cause KGDB to reenter, which we don't want. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Acked-by: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* kernel/debug: Make use of KGDB_REASON_NMIAnton Vorontsov2012-07-311-0/+4
| | | | | | | | | | | | Currently kernel never set KGDB_REASON_NMI. We do now, when we enter KGDB/KDB from an NMI. This is not to be confused with kgdb_nmicallback(), NMI callback is an entry for the slave CPUs during CPUs roundup, but REASON_NMI is the entry for the master CPU. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* kdb: Remove cpu from the more promptJason Wessel2012-07-311-11/+0
| | | | | | | Having the CPU in the more prompt is completely redundent vs the standard kdb prompt, and it also wastes 32 bytes on the stack. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* kdb: Remove unused KDB_FLAG_ONLY_DO_DUMPJason Wessel2012-07-311-14/+1
| | | | | | | | This code cleanup was missed in the original kdb merge, and this code is simply not used at all. The code that was previously used to set the KDB_FLAG_ONLY_DO_DUMP was removed prior to the initial kdb merge. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* kdb: Switch to nolock variants of kmsg_dump functionsAnton Vorontsov2012-07-211-4/+4
| | | | | | | | The locked variants are prone to deadlocks (suppose we got to the debugger w/ the logbuf lock held), so let's switch to nolock variants. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* printk: Remove kdb_syslog_dataAnton Vorontsov2012-07-211-1/+0
| | | | | | | The function is no longer needed, so remove it. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* kdb: Revive dmesg commandAnton Vorontsov2012-07-211-58/+33
| | | | | | | | | | | | | The kgdb dmesg command is broken after the printk rework. The old logic in kdb code makes no sense in terms of current printk/logging storage format, and KDB simply hangs forever. This patch revives the command by switching to kmsg_dumper iterator. The code is now much more simpler and shorter. Signed-off-by: Anton Vorontsov <anton.vorontsov@linaro.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge tag 'for_linus-3.4-rc2' of ↵Linus Torvalds2012-04-042-30/+25
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull KGDB/KDB regression fixes from Jason Wessel: - Fix a Smatch warning that appeared in the 3.4 merge window - Fix kgdb test suite with SMP for all archs without HW single stepping - Fix kgdb sw breakpoints with CONFIG_DEBUG_RODATA=y limitations on x86 - Fix oops on kgdb test suite with CONFIG_DEBUG_RODATA - Fix kgdb test suite with SMP for all archs with HW single stepping * tag 'for_linus-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: x86,kgdb: Fix DEBUG_RODATA limitation using text_poke() kgdb,debug_core: pass the breakpoint struct instead of address and memory kgdbts: (2 of 2) fix single step awareness to work correctly with SMP kgdbts: (1 of 2) fix single step awareness to work correctly with SMP kgdbts: Fix kernel oops with CONFIG_DEBUG_RODATA kdb: Fix smatch warning on dbg_io_ops->is_console
| * kgdb,debug_core: pass the breakpoint struct instead of address and memoryJason Wessel2012-03-291-29/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is extra state information that needs to be exposed in the kgdb_bpt structure for tracking how a breakpoint was installed. The debug_core only uses the the probe_kernel_write() to install breakpoints, but this is not enough for all the archs. Some arch such as x86 need to use text_poke() in order to install a breakpoint into a read only page. Passing the kgdb_bpt structure to kgdb_arch_set_breakpoint() and kgdb_arch_remove_breakpoint() allows other archs to set the type variable which indicates how the breakpoint was installed. Cc: stable@vger.kernel.org # >= 2.6.36 Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Fix smatch warning on dbg_io_ops->is_consoleJason Wessel2012-03-291-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The Smatch tool warned that the change from commit b8adde8dd (kdb: Avoid using dbg_io_ops until it is initialized) should add another null check later in the kdb_printf(). It is worth noting that the second use of dbg_io_ops->is_console is protected by the KDB_PAGER state variable which would only get set when kdb is fully active and initialized. If we ever encounter changes or defects in the KDB_PAGER state we do not want to crash the kernel in a kdb_printf/printk. CC: Tim Bird <tim.bird@am.sony.com> Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | Merge tag 'split-asm_system_h-for-linus-20120328' of ↵Linus Torvalds2012-03-282-2/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system Pull "Disintegrate and delete asm/system.h" from David Howells: "Here are a bunch of patches to disintegrate asm/system.h into a set of separate bits to relieve the problem of circular inclusion dependencies. I've built all the working defconfigs from all the arches that I can and made sure that they don't break. The reason for these patches is that I recently encountered a circular dependency problem that came about when I produced some patches to optimise get_order() by rewriting it to use ilog2(). This uses bitops - and on the SH arch asm/bitops.h drags in asm-generic/get_order.h by a circuituous route involving asm/system.h. The main difficulty seems to be asm/system.h. It holds a number of low level bits with no/few dependencies that are commonly used (eg. memory barriers) and a number of bits with more dependencies that aren't used in many places (eg. switch_to()). These patches break asm/system.h up into the following core pieces: (1) asm/barrier.h Move memory barriers here. This already done for MIPS and Alpha. (2) asm/switch_to.h Move switch_to() and related stuff here. (3) asm/exec.h Move arch_align_stack() here. Other process execution related bits could perhaps go here from asm/processor.h. (4) asm/cmpxchg.h Move xchg() and cmpxchg() here as they're full word atomic ops and frequently used by atomic_xchg() and atomic_cmpxchg(). (5) asm/bug.h Move die() and related bits. (6) asm/auxvec.h Move AT_VECTOR_SIZE_ARCH here. Other arch headers are created as needed on a per-arch basis." Fixed up some conflicts from other header file cleanups and moving code around that has happened in the meantime, so David's testing is somewhat weakened by that. We'll find out anything that got broken and fix it.. * tag 'split-asm_system_h-for-linus-20120328' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-asm_system: (38 commits) Delete all instances of asm/system.h Remove all #inclusions of asm/system.h Add #includes needed to permit the removal of asm/system.h Move all declarations of free_initmem() to linux/mm.h Disintegrate asm/system.h for OpenRISC Split arch_align_stack() out from asm-generic/system.h Split the switch_to() wrapper out of asm-generic/system.h Move the asm-generic/system.h xchg() implementation to asm-generic/cmpxchg.h Create asm-generic/barrier.h Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h Disintegrate asm/system.h for Xtensa Disintegrate asm/system.h for Unicore32 [based on ver #3, changed by gxt] Disintegrate asm/system.h for Tile Disintegrate asm/system.h for Sparc Disintegrate asm/system.h for SH Disintegrate asm/system.h for Score Disintegrate asm/system.h for S390 Disintegrate asm/system.h for PowerPC Disintegrate asm/system.h for PA-RISC Disintegrate asm/system.h for MN10300 ...
| * | Remove all #inclusions of asm/system.hDavid Howells2012-03-282-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | Remove all #inclusions of asm/system.h preparatory to splitting and killing it. Performed with the following command: perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *` Signed-off-by: David Howells <dhowells@redhat.com>
* | | Merge tag 'for_linus-3.4-rc1' of ↵Linus Torvalds2012-03-237-24/+133
|\ \ \ | |/ / |/| / | |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb Pull KGDB/KDB updates from Jason Wessel: "Fixes: - Fix KDB keyboard repeat scan codes and leaked keyboard events - Fix kernel crash with kdb_printf() for users who compile new kdb_printf()'s in early code - Return all segment registers to gdb on x86_64 Features: - KDB/KGDB hook the reboot notifier and end user can control if it stops, detaches or does nothing (updated docs as well) - Notify users who use CONFIG_DEBUG_RODATA to use hw breakpoints" * tag 'for_linus-3.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/kgdb: kdb: Add message about CONFIG_DEBUG_RODATA on failure to install breakpoint kdb: Avoid using dbg_io_ops until it is initialized kgdb,debug_core: add the ability to control the reboot notifier KDB: Fix usability issues relating to the 'enter' key. kgdb,debug-core,gdbstub: Hook the reboot notifier for debugger detach kgdb: Respect that flush op is optional kgdb: x86: Return all segment registers also in 64-bit mode
| * kdb: Add message about CONFIG_DEBUG_RODATA on failure to install breakpointJason Wessel2012-03-221-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | On x86, if CONFIG_DEBUG_RODATA is set, one cannot set breakpoints via KDB. Apparently this is a well-known problem, as at least one distribution now ships with both KDB enabled and CONFIG_DEBUG_RODATA=y for security reasons. This patch adds an printk message to the breakpoint failure case, in order to provide suggestions about how to use the debugger. Reported-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com> Acked-by: Tim Bird <tim.bird@am.sony.com>
| * kdb: Avoid using dbg_io_ops until it is initializedTim Bird2012-03-221-1/+1
| | | | | | | | | | | | | | | | | | | | | | This fixes a bug with setting a breakpoint during kdb initialization (from kdb_cmds). Any call to kdb_printf() before the initialization of the kgdboc serial console driver (which happens much later during bootup than kdb_init), results in kernel panic due to the use of dbg_io_ops before it is initialized. Signed-off-by: Tim Bird <tim.bird@am.sony.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kgdb,debug_core: add the ability to control the reboot notifierJason Wessel2012-03-221-0/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sometimes it is desirable to stop the kernel debugger before allowing a system to reboot either with kdb or kgdb. This patch adds the ability to turn the reboot notifier on and off or enter the debugger and stop kernel execution before rebooting. It is possible to change the setting after booting the kernel with the following: echo 1 > /sys/module/debug_core/parameters/kgdbreboot It is also possible to change this setting using kdb / kgdb to manipulate the variable directly. Using KDB: mm kgdbreboot 1 Using gdb: set kgdbreboot=1 Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * KDB: Fix usability issues relating to the 'enter' key.Andrei Warkentin2012-03-223-22/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This fixes the following problems: 1) Typematic-repeat of 'enter' gives warning message and leaks make/break if KDB exits. Repeats look something like 0x1c 0x1c .... 0x9c 2) Use of 'keypad enter' gives warning message and leaks the ENTER break/make code out if KDB exits. KP ENTER repeats look someting like 0xe0 0x1c 0xe0 0x1c ... 0xe0 0x9c. 3) Lag on the order of seconds between "break" and "make" when expecting the enter "break" code. Seen under virtualized environments such as VMware ESX. The existing special enter handler tries to glob the enter break code, but this fails if the other (KP) enter was used, or if there was a key repeat. It also fails if you mashed some keys along with enter, and you ended up with a non-enter make or non-enter break code coming after the enter make code. So first, we modify the handler to handle these cases. But performing these actions on every enter is annoying since now you can't hold ENTER down to scroll <more>d messages in KDB. Since this special behaviour is only necessary to handle the exiting KDB ('g' + ENTER) without leaking scancodes to the OS. This cleanup needs to get executed anytime the kdb_main loop exits. Tested on QEMU. Set a bp on atkbd.c to verify no scan code was leaked. Cc: Andrei Warkentin <andreiw@vmware.com> [jason.wessel@windriver.com: move cleanup calls to kdb_main.c] Signed-off-by: Andrei Warkentin <andrey.warkentin@gmail.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kgdb,debug-core,gdbstub: Hook the reboot notifier for debugger detachJason Wessel2012-03-222-0/+24
| | | | | | | | | | | | | | | | | | | | | | | | The gdbstub and kdb should get detached if the system is rebooting. Calling gdbstub_exit() will set the proper debug core state and send a message to any debugger that is connected to correctly detach. An attached debugger will receive the exit code from include/linux/reboot.h based on SYS_HALT, SYS_REBOOT, etc... Reported-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kgdb: Respect that flush op is optionalJan Kiszka2012-03-221-1/+2
| | | | | | | | | | | | | | | | Not all kgdb I/O drivers implement a flush operation. Adjust gdbstub_exit accordingly. Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
* | kdb: remove the second argument of k[un]map_atomic()Cong Wang2012-03-201-2/+2
|/ | | | Signed-off-by: Cong Wang <amwang@redhat.com>
* module: struct module_ref should contains long fieldsEric Dumazet2012-01-131-1/+1
| | | | | | | | | | | | | | | | | | | module_ref contains two "unsigned int" fields. Thats now too small, since some machines can open more than 2^32 files. Check commit 518de9b39e8 (fs: allow for more than 2^31 files) for reference. We can add an aligned(2 * sizeof(unsigned long)) attribute to force alloc_percpu() allocating module_ref areas in single cache lines. Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com> CC: Rusty Russell <rusty@rustcorp.com.au> CC: Tejun Heo <tj@kernel.org> CC: Robin Holt <holt@sgi.com> CC: David Miller <davem@davemloft.net> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* kdb: Make KDB use the new is_idle_task() APIPaul E. McKenney2011-12-111-1/+1
| | | | | | | | | Change from direct comparison of ->pid with zero to is_idle_task(). Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Jason Wessel <jason.wessel@windriver.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
* Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds2011-11-061-0/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
| * kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructurePaul Gortmaker2011-10-311-0/+1
| | | | | | | | | | | | | | | | | | | | These files were getting <linux/module.h> via an implicit non-obvious path, but we want to crush those out of existence since they cost time during compiles of processing thousands of lines of headers for no reason. Give them the lightweight header that just contains the EXPORT_SYMBOL infrastructure. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | kgdb: follow rename pack_hex_byte() to hex_byte_pack()Andy Shevchenko2011-10-311-6/+6
|/ | | | | | | | | | | | There is no functional change. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jesper Nilsson <jesper.nilsson@axis.com> Cc: David Howells <dhowells@redhat.com> Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com> Cc: Jason Wessel <jason.wessel@windriver.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* Merge branch 'for_linus' of ↵Linus Torvalds2011-08-017-42/+53
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb: kdb,kgdb: Allow arbitrary kgdb magic knock sequences kdb: Remove all references to DOING_KGDB2 kdb,kgdb: Implement switch and pass buffer from kdb -> gdb kdb: cleanup unused variables missed in the original kdb merge
| * kdb,kgdb: Allow arbitrary kgdb magic knock sequencesJason Wessel2011-08-011-8/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The first packet that gdb sends when the kernel is in kdb mode seems to change with every release of gdb. Instead of continuing to add many different gdb packets, change kdb to automatically look for any thing that looks like a gdb packet. Example 1 cold start test: echo g > /proc/sysrq-trigger $D#44+ Example 2 cold start test: echo g > /proc/sysrq-trigger $3#33 The second one should re-enter kdb's shell right away and is purely a test. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb: Remove all references to DOING_KGDB2Jason Wessel2011-08-014-7/+3
| | | | | | | | | | | | | | | | The DOING_KGDB2 was originally a state variable for one of the two ways to automatically transition from kdb to kgdb. Purge all these variables and just use one single state for the transition. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
| * kdb,kgdb: Implement switch and pass buffer from kdb -> gdbJason Wessel2011-08-014-21/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | When switching from kdb mode to kgdb mode packets were getting lost depending on the size of the fifo queue of the serial chip. When gdb initially connects if it is in kdb mode it should entirely send any character buffer over to the gdbstub when switching connections. Previously kdb was zero'ing out the character buffer and this could lead to gdb failing to connect at all, or a lengthy pause could occur on the initial connect. Signed-off-by: Jason Wessel <jason.wessel@windriver.com>
OpenPOWER on IntegriCloud