summaryrefslogtreecommitdiff
path: root/arch/arm/kernel/ftrace.c
AgeCommit message (Collapse)Author
2017-06-18ARM: 8678/1: ftrace: Adds support for CONFIG_DYNAMIC_FTRACE_WITH_REGSAbel Vesa
The DYNAMIC_FTRACE_WITH_REGS configuration makes it possible for a ftrace operation to specify if registers need to saved/restored by the ftrace handler. This is needed by kgraft and possibly other ftrace-based tools, and the ARM architecture is currently lacking this feature. It would also be the first step to support the "Kprobes-on-ftrace" optimization on ARM. This patch introduces a new ftrace handler that stores the registers on the stack before calling the next stage. The registers are restored from the stack before going back to the instrumented function. A side-effect of this patch is to activate the support for ftrace_modify_call() as it defines ARCH_SUPPORTS_FTRACE_OPS for the ARM architecture. Signed-off-by: Abel Vesa <abelvesa@linux.com> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2017-05-08Merge branch 'akpm' (patches from Andrew)Linus Torvalds
Merge more updates from Andrew Morton: - the rest of MM - various misc things - procfs updates - lib/ updates - checkpatch updates - kdump/kexec updates - add kvmalloc helpers, use them - time helper updates for Y2038 issues. We're almost ready to remove current_fs_time() but that awaits a btrfs merge. - add tracepoints to DAX * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (114 commits) drivers/staging/ccree/ssi_hash.c: fix build with gcc-4.4.4 selftests/vm: add a test for virtual address range mapping dax: add tracepoint to dax_insert_mapping() dax: add tracepoint to dax_writeback_one() dax: add tracepoints to dax_writeback_mapping_range() dax: add tracepoints to dax_load_hole() dax: add tracepoints to dax_pfn_mkwrite() dax: add tracepoints to dax_iomap_pte_fault() mtd: nand: nandsim: convert to memalloc_noreclaim_*() treewide: convert PF_MEMALLOC manipulations to new helpers mm: introduce memalloc_noreclaim_{save,restore} mm: prevent potential recursive reclaim due to clearing PF_MEMALLOC mm/huge_memory.c: deposit a pgtable for DAX PMD faults when required mm/huge_memory.c: use zap_deposited_table() more time: delete CURRENT_TIME_SEC and CURRENT_TIME gfs2: replace CURRENT_TIME with current_time apparmorfs: replace CURRENT_TIME with current_time() lustre: replace CURRENT_TIME macro fs: ubifs: replace CURRENT_TIME_SEC with current_time fs: ufs: use ktime_get_real_ts64() for birthtime ...
2017-05-08arm: use set_memory.h headerLaura Abbott
set_memory_* functions have moved to set_memory.h. Switch to this explicitly Link: http://lkml.kernel.org/r/1488920133-27229-3-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-20ARM: 8668/1: ftrace: Fix dynamic ftrace with DEBUG_RODATA and !FRAME_POINTERAbel Vesa
The support for dynamic ftrace with CONFIG_DEBUG_RODATA involves overriding the weak arch_ftrace_update_code() with a variant which makes the kernel text writable around the patching. This override was however added under the CONFIG_OLD_MCOUNT ifdef, and CONFIG_OLD_MCOUNT is only enabled if frame pointers are enabled. This leads to non-functional dynamic ftrace (ftrace triggers a WARN_ON()) when CONFIG_DEBUG_RODATA is enabled and CONFIG_FRAME_POINTER is not. Move the override out of that ifdef and into the CONFIG_DYNAMIC_FTRACE ifdef where it belongs. Fixes: 80d6b0c2eed2a ("ARM: mm: allow text and rodata sections to be read-only") Suggested-by: Nicolai Stange <nicstange@gmail.com> Suggested-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Abel Vesa <abelvesa@gmail.com> Acked-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
2016-08-24ftrace: Add return address pointer to ftrace_ret_stackJosh Poimboeuf
Storing this value will help prevent unwinders from getting out of sync with the function graph tracer ret_stack. Now instead of needing a stateful iterator, they can compare the return address pointer to find the right ret_stack entry. Note that an array of 50 ftrace_ret_stack structs is allocated for every task. So when an arch implements this, it will add either 200 or 400 bytes of memory usage per task (depending on whether it's a 32-bit or 64-bit platform). Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nilay Vaish <nilayvaish@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/a95cfcc39e8f26b89a430c56926af0bb217bc0a1.1471607358.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2015-01-13ARM: kprobes: enable OPTPROBES for ARM 32Wang Nan
This patch introduce kprobeopt for ARM 32. Limitations: - Currently only kernel compiled with ARM ISA is supported. - Offset between probe point and optinsn slot must not larger than 32MiB. Masami Hiramatsu suggests replacing 2 words, it will make things complex. Futher patch can make such optimization. Kprobe opt on ARM is relatively simpler than kprobe opt on x86 because ARM instruction is always 4 bytes aligned and 4 bytes long. This patch replace probed instruction by a 'b', branch to trampoline code and then calls optimized_callback(). optimized_callback() calls opt_pre_handler() to execute kprobe handler. It also emulate/simulate replaced instruction. When unregistering kprobe, the deferred manner of unoptimizer may leave branch instruction before optimizer is called. Different from x86_64, which only copy the probed insn after optprobe_template_end and reexecute them, this patch call singlestep to emulate/simulate the insn directly. Futher patch can optimize this behavior. Signed-off-by: Wang Nan <wangnan0@huawei.com> Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Jon Medhurst (Tixy) <tixy@linaro.org> Signed-off-by: Jon Medhurst <tixy@linaro.org>
2014-10-16ARM: mm: allow text and rodata sections to be read-onlyKees Cook
This introduces CONFIG_DEBUG_RODATA, making kernel text and rodata read-only. Additionally, this splits rodata from text so that rodata can also be NX, which may lead to wasted memory when aligning to SECTION_SIZE. The read-only areas are made writable during ftrace updates and kexec. Signed-off-by: Kees Cook <keescook@chromium.org> Tested-by: Laura Abbott <lauraa@codeaurora.org> Acked-by: Nicolas Pitre <nico@linaro.org>
2014-04-23ARM: 8022/1: ftrace: work with CONFIG_DEBUG_SET_MODULE_RONXRabin Vincent
Make ftrace work with CONFIG_DEBUG_SET_MODULE_RONX by making module text writable around the place where ftrace does its work, like it is done on x86 in the patch which introduced CONFIG_DEBUG_SET_MODULE_RONX, 84e1c6bb38eb ("x86: Add RO/NX protection for loadable kernel modules"). Tested-by: Mitchel Humpherys <mitchelh@codeaurora.org> Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2014-03-07ftrace: Do not pass data to ftrace_dyn_arch_initJiri Slaby
As the data parameter is not really used by any ftrace_dyn_arch_init, remove that from ftrace_dyn_arch_init. This also removes the addr local variable from ftrace_init which is now unused. Note the documentation was imprecise as it did not suggest to set (*data) to 0. Link: http://lkml.kernel.org/r/1393268401-24379-4-git-send-email-jslaby@suse.cz Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: linux-arch@vger.kernel.org Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2014-03-07ftrace: Pass retval through return in ftrace_dyn_arch_init()Jiri Slaby
No architecture uses the "data" parameter in ftrace_dyn_arch_init() in any way, it just sets the value to 0. And this is used as a return value in the caller -- ftrace_init, which just checks the retval against zero. Note there is also "return 0" in every ftrace_dyn_arch_init. So it is enough to check the retval and remove all the indirect sets of data on all archs. Link: http://lkml.kernel.org/r/1393268401-24379-3-git-send-email-jslaby@suse.cz Cc: linux-arch@vger.kernel.org Signed-off-by: Jiri Slaby <jslaby@suse.cz> Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2012-07-31ARM: 7468/1: ftrace: Trace function entry before updating indexColin Cross
Commit 722b3c74695377d11d18a52f3da08114d37f3f37 modified x86 ftrace to avoid tracing all functions called from irqs when function graph was used with a filter. Port the same fix to ARM. Acked-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-24ARM: 7331/1: extract out insn generation code from ftraceRabin Vincent
Extract out the instruction generation code so that it can be used for jump labels too. Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-24ARM: 7330/1: ftrace: use canonical Thumb-2 wide instruction formatRabin Vincent
As commit 592201a9f15 (ARM: Thumb-2: Support Thumb-2 in undefined instruction handler) says: 32-bit Thumb instructions are specified in the form: ((first_half << 16 ) | second_half) which matches the layout used by the ARM ARM. Convert the ftrace code to use the same format to avoid the usage of different formats in kernel code. Acked-by: Dave Martin <dave.martin@linaro.org> Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2012-03-24ARM: 7351/1: ftrace: remove useless memory checksRabin Vincent
Before replacing an instruction, the ftrace code determines what the old instruction should be and verifies that that's what's really there in memory before replacing it. This is useful if for example a bug in mcountrecord causes it to record wrong locations. However, in cases where we replace call sites in entry-common.S, these checks are not needed. For these, we currently just memcpy() the memory content and then "verify" it -- this is quite useless and can be removed. Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-11-19ARM: ftrace: graph tracer + dynamic ftraceRabin Vincent
Support the graph tracer + dynamic ftrace combination on ARM. Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-11-19ARM: ftrace: function graph tracer supportTim Bird
Cc: Tim Bird <tim.bird@am.sony.com> [rabin@rab.in: rebase on top of latest code, keep code in ftrace.c instead of separate file, check for ftrace_graph_entry also] Signed-off-by: Rabin Vincent <rabin@rab.in>
2010-09-02ARM: 6319/1: ftrace: add Thumb-2 support to dynamic ftraceRabin Vincent
Handle the different nop and call instructions for Thumb-2. Also, we need to adjust the recorded mcount_loc addresses because they have the lsb set. Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change] Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-09-02ARM: 6318/1: ftrace: fix and update dynamic ftraceRabin Vincent
This adds mcount recording and updates dynamic ftrace for ARM to work with the new ftrace dyamic tracing implementation. It also adds support for the mcount format used by newer ARM compilers. With dynamic tracing, mcount() is implemented as a nop. Callsites are patched on startup with nops, and dynamically patched to call to the ftrace_caller() routine as needed. Acked-by: Steven Rostedt <rostedt@goodmis.org> [recordmcount.pl change] Signed-off-by: Rabin Vincent <rabin@rab.in> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2010-04-21ARM: fix build error in arch/arm/kernel/process.cRussell King
/tmp/ccJ3ssZW.s: Assembler messages: /tmp/ccJ3ssZW.s:1952: Error: can't resolve `.text' {.text section} - `.LFB1077' This is caused because: .section .data .section .text .section .text .previous does not return us to the .text section, but the .data section; this makes use of .previous dangerous if the ordering of previous sections is not known. Fix up the other users of .previous; .pushsection and .popsection are a safer pairing to use than .section and .previous. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-12-12small doc fix: ftrace_dyn_arch_init is called by ftrace_initUwe Kleine-König
... not kstop_machine. Add a note that irqs are disabled. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2008-10-23ftrace: remove mcount setSteven Rostedt
The arch dependent function ftrace_mcount_set was only used by the daemon start up code. This patch removes it. Signed-off-by: Steven Rostedt <srostedt@redhat.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-23ftrace: store mcount address in rec->ipAbhishek Sagar
Record the address of the mcount call-site. Currently all archs except sparc64 record the address of the instruction following the mcount call-site. Some general cleanups are entailed. Storing mcount addresses in rec->ip enables looking them up in the kprobe hash table later on to check if they're kprobe'd. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Cc: davem@davemloft.net Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-10ftrace: remove ftrace_ip_converted()Abhishek Sagar
Remove the unneeded function ftrace_ip_converted(). Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-06-02ftrace: core support for ARMAbhishek Sagar
Core ftrace support for the ARM architecture, which includes support for dynamic function tracing. Signed-off-by: Abhishek Sagar <sagar.abhishek@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>