diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-09 16:39:15 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-09 16:39:15 -0700 |
commit | 214b93132023cc9305d5801add812515bea4d7d0 (patch) | |
tree | bb8db8677dd80b6ef570b8aa59475b072b81db11 /arch/x86/kernel | |
parent | 14208b0ec56919f5333dd654b1a7d10765d0ad05 (diff) | |
parent | a9fcaaac37b3baba1343f906f52aeb65c4d4e356 (diff) |
Merge tag 'trace-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"Lots of tweaks, small fixes, optimizations, and some helper functions
to help out the rest of the kernel to ease their use of trace events.
The big change for this release is the allowing of other tracers, such
as the latency tracers, to be used in the trace instances and allow
for function or function graph tracing to be in the top level
simultaneously"
* tag 'trace-3.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits)
tracing: Fix memory leak on instance deletion
tracing: Fix leak of ring buffer data when new instances creation fails
tracing/kprobes: Avoid self tests if tracing is disabled on boot up
tracing: Return error if ftrace_trace_arrays list is empty
tracing: Only calculate stats of tracepoint benchmarks for 2^32 times
tracing: Convert stddev into u64 in tracepoint benchmark
tracing: Introduce saved_cmdlines_size file
tracing: Add __get_dynamic_array_len() macro for trace events
tracing: Remove unused variable in trace_benchmark
tracing: Eliminate double free on failure of allocation on boot up
ftrace/x86: Call text_ip_addr() instead of the duplicated code
tracing: Print max callstack on stacktrace bug
tracing: Move locking of trace_cmdline_lock into start/stop seq calls
tracing: Try again for saved cmdline if failed due to locking
tracing: Have saved_cmdlines use the seq_read infrastructure
tracing: Add tracepoint benchmark tracepoint
tracing: Print nasty banner when trace_printk() is in use
tracing: Add funcgraph_tail option to print function name after closing braces
tracing: Eliminate duplicate TRACE_GRAPH_PRINT_xx defines
tracing: Add __bitmask() macro to trace events to cpumasks and other bitmasks
...
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r-- | arch/x86/kernel/Makefile | 1 | ||||
-rw-r--r-- | arch/x86/kernel/entry_64.S | 204 | ||||
-rw-r--r-- | arch/x86/kernel/ftrace.c | 56 | ||||
-rw-r--r-- | arch/x86/kernel/mcount_64.S | 217 |
4 files changed, 226 insertions, 252 deletions
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 491ef3e59850..047f9ff2e36c 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_IRQ_WORK) += irq_work.o obj-y += probe_roms.o obj-$(CONFIG_X86_32) += i386_ksyms_32.o obj-$(CONFIG_X86_64) += sys_x86_64.o x8664_ksyms_64.o +obj-$(CONFIG_X86_64) += mcount_64.o obj-y += syscall_$(BITS).o vsyscall_gtod.o obj-$(CONFIG_X86_64) += vsyscall_64.o obj-$(CONFIG_X86_64) += vsyscall_emu_64.o diff --git a/arch/x86/kernel/entry_64.S b/arch/x86/kernel/entry_64.S index 96987987c5de..48a2644a082a 100644 --- a/arch/x86/kernel/entry_64.S +++ b/arch/x86/kernel/entry_64.S @@ -53,7 +53,6 @@ #include <asm/page_types.h> #include <asm/irqflags.h> #include <asm/paravirt.h> -#include <asm/ftrace.h> #include <asm/percpu.h> #include <asm/asm.h> #include <asm/context_tracking.h> @@ -70,209 +69,6 @@ .code64 .section .entry.text, "ax" -#ifdef CONFIG_FUNCTION_TRACER - -#ifdef CC_USING_FENTRY -# define function_hook __fentry__ -#else -# define function_hook mcount -#endif - -#ifdef CONFIG_DYNAMIC_FTRACE - -ENTRY(function_hook) - retq -END(function_hook) - -/* skip is set if stack has been adjusted */ -.macro ftrace_caller_setup skip=0 - MCOUNT_SAVE_FRAME \skip - - /* Load the ftrace_ops into the 3rd parameter */ - movq function_trace_op(%rip), %rdx - - /* Load ip into the first parameter */ - movq RIP(%rsp), %rdi - subq $MCOUNT_INSN_SIZE, %rdi - /* Load the parent_ip into the second parameter */ -#ifdef CC_USING_FENTRY - movq SS+16(%rsp), %rsi -#else - movq 8(%rbp), %rsi -#endif -.endm - -ENTRY(ftrace_caller) - /* Check if tracing was disabled (quick check) */ - cmpl $0, function_trace_stop - jne ftrace_stub - - ftrace_caller_setup - /* regs go into 4th parameter (but make it NULL) */ - movq $0, %rcx - -GLOBAL(ftrace_call) - call ftrace_stub - - MCOUNT_RESTORE_FRAME -ftrace_return: - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -GLOBAL(ftrace_graph_call) - jmp ftrace_stub -#endif - -GLOBAL(ftrace_stub) - retq -END(ftrace_caller) - -ENTRY(ftrace_regs_caller) - /* Save the current flags before compare (in SS location)*/ - pushfq - - /* Check if tracing was disabled (quick check) */ - cmpl $0, function_trace_stop - jne ftrace_restore_flags - - /* skip=8 to skip flags saved in SS */ - ftrace_caller_setup 8 - - /* Save the rest of pt_regs */ - movq %r15, R15(%rsp) - movq %r14, R14(%rsp) - movq %r13, R13(%rsp) - movq %r12, R12(%rsp) - movq %r11, R11(%rsp) - movq %r10, R10(%rsp) - movq %rbp, RBP(%rsp) - movq %rbx, RBX(%rsp) - /* Copy saved flags */ - movq SS(%rsp), %rcx - movq %rcx, EFLAGS(%rsp) - /* Kernel segments */ - movq $__KERNEL_DS, %rcx - movq %rcx, SS(%rsp) - movq $__KERNEL_CS, %rcx - movq %rcx, CS(%rsp) - /* Stack - skipping return address */ - leaq SS+16(%rsp), %rcx - movq %rcx, RSP(%rsp) - - /* regs go into 4th parameter */ - leaq (%rsp), %rcx - -GLOBAL(ftrace_regs_call) - call ftrace_stub - - /* Copy flags back to SS, to restore them */ - movq EFLAGS(%rsp), %rax - movq %rax, SS(%rsp) - - /* Handlers can change the RIP */ - movq RIP(%rsp), %rax - movq %rax, SS+8(%rsp) - - /* restore the rest of pt_regs */ - movq R15(%rsp), %r15 - movq R14(%rsp), %r14 - movq R13(%rsp), %r13 - movq R12(%rsp), %r12 - movq R10(%rsp), %r10 - movq RBP(%rsp), %rbp - movq RBX(%rsp), %rbx - - /* skip=8 to skip flags saved in SS */ - MCOUNT_RESTORE_FRAME 8 - - /* Restore flags */ - popfq - - jmp ftrace_return -ftrace_restore_flags: - popfq - jmp ftrace_stub - -END(ftrace_regs_caller) - - -#else /* ! CONFIG_DYNAMIC_FTRACE */ - -ENTRY(function_hook) - cmpl $0, function_trace_stop - jne ftrace_stub - - cmpq $ftrace_stub, ftrace_trace_function - jnz trace - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - cmpq $ftrace_stub, ftrace_graph_return - jnz ftrace_graph_caller - - cmpq $ftrace_graph_entry_stub, ftrace_graph_entry - jnz ftrace_graph_caller -#endif - -GLOBAL(ftrace_stub) - retq - -trace: - MCOUNT_SAVE_FRAME - - movq RIP(%rsp), %rdi -#ifdef CC_USING_FENTRY - movq SS+16(%rsp), %rsi -#else - movq 8(%rbp), %rsi -#endif - subq $MCOUNT_INSN_SIZE, %rdi - - call *ftrace_trace_function - - MCOUNT_RESTORE_FRAME - - jmp ftrace_stub -END(function_hook) -#endif /* CONFIG_DYNAMIC_FTRACE */ -#endif /* CONFIG_FUNCTION_TRACER */ - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -ENTRY(ftrace_graph_caller) - MCOUNT_SAVE_FRAME - -#ifdef CC_USING_FENTRY - leaq SS+16(%rsp), %rdi - movq $0, %rdx /* No framepointers needed */ -#else - leaq 8(%rbp), %rdi - movq (%rbp), %rdx -#endif - movq RIP(%rsp), %rsi - subq $MCOUNT_INSN_SIZE, %rsi - - call prepare_ftrace_return - - MCOUNT_RESTORE_FRAME - - retq -END(ftrace_graph_caller) - -GLOBAL(return_to_handler) - subq $24, %rsp - - /* Save the return values */ - movq %rax, (%rsp) - movq %rdx, 8(%rsp) - movq %rbp, %rdi - - call ftrace_return_to_handler - - movq %rax, %rdi - movq 8(%rsp), %rdx - movq (%rsp), %rax - addq $24, %rsp - jmp *%rdi -#endif - #ifndef CONFIG_PREEMPT #define retint_kernel retint_restore_args diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index 52819e816f87..cbc4a91b131e 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -297,16 +297,7 @@ int ftrace_int3_handler(struct pt_regs *regs) static int ftrace_write(unsigned long ip, const char *val, int size) { - /* - * On x86_64, kernel text mappings are mapped read-only with - * CONFIG_DEBUG_RODATA. So we use the kernel identity mapping instead - * of the kernel text mapping to modify the kernel text. - * - * For 32bit kernels, these mappings are same and we can use - * kernel identity mapping to modify code. - */ - if (within(ip, (unsigned long)_text, (unsigned long)_etext)) - ip = (unsigned long)__va(__pa_symbol(ip)); + ip = text_ip_addr(ip); if (probe_kernel_write((void *)ip, val, size)) return -EPERM; @@ -349,40 +340,14 @@ static int add_brk_on_nop(struct dyn_ftrace *rec) return add_break(rec->ip, old); } -/* - * If the record has the FTRACE_FL_REGS set, that means that it - * wants to convert to a callback that saves all regs. If FTRACE_FL_REGS - * is not not set, then it wants to convert to the normal callback. - */ -static unsigned long get_ftrace_addr(struct dyn_ftrace *rec) -{ - if (rec->flags & FTRACE_FL_REGS) - return (unsigned long)FTRACE_REGS_ADDR; - else - return (unsigned long)FTRACE_ADDR; -} - -/* - * The FTRACE_FL_REGS_EN is set when the record already points to - * a function that saves all the regs. Basically the '_EN' version - * represents the current state of the function. - */ -static unsigned long get_ftrace_old_addr(struct dyn_ftrace *rec) -{ - if (rec->flags & FTRACE_FL_REGS_EN) - return (unsigned long)FTRACE_REGS_ADDR; - else - return (unsigned long)FTRACE_ADDR; -} - static int add_breakpoints(struct dyn_ftrace *rec, int enable) { unsigned long ftrace_addr; int ret; - ret = ftrace_test_record(rec, enable); + ftrace_addr = ftrace_get_addr_curr(rec); - ftrace_addr = get_ftrace_addr(rec); + ret = ftrace_test_record(rec, enable); switch (ret) { case FTRACE_UPDATE_IGNORE: @@ -392,10 +357,7 @@ static int add_breakpoints(struct dyn_ftrace *rec, int enable) /* converting nop to call */ return add_brk_on_nop(rec); - case FTRACE_UPDATE_MODIFY_CALL_REGS: case FTRACE_UPDATE_MODIFY_CALL: - ftrace_addr = get_ftrace_old_addr(rec); - /* fall through */ case FTRACE_UPDATE_MAKE_NOP: /* converting a call to a nop */ return add_brk_on_call(rec, ftrace_addr); @@ -440,14 +402,14 @@ static int remove_breakpoint(struct dyn_ftrace *rec) * If not, don't touch the breakpoint, we make just create * a disaster. */ - ftrace_addr = get_ftrace_addr(rec); + ftrace_addr = ftrace_get_addr_new(rec); nop = ftrace_call_replace(ip, ftrace_addr); if (memcmp(&ins[1], &nop[1], MCOUNT_INSN_SIZE - 1) == 0) goto update; /* Check both ftrace_addr and ftrace_old_addr */ - ftrace_addr = get_ftrace_old_addr(rec); + ftrace_addr = ftrace_get_addr_curr(rec); nop = ftrace_call_replace(ip, ftrace_addr); if (memcmp(&ins[1], &nop[1], MCOUNT_INSN_SIZE - 1) != 0) @@ -491,13 +453,12 @@ static int add_update(struct dyn_ftrace *rec, int enable) ret = ftrace_test_record(rec, enable); - ftrace_addr = get_ftrace_addr(rec); + ftrace_addr = ftrace_get_addr_new(rec); switch (ret) { case FTRACE_UPDATE_IGNORE: return 0; - case FTRACE_UPDATE_MODIFY_CALL_REGS: case FTRACE_UPDATE_MODIFY_CALL: case FTRACE_UPDATE_MAKE_CALL: /* converting nop to call */ @@ -538,13 +499,12 @@ static int finish_update(struct dyn_ftrace *rec, int enable) ret = ftrace_update_record(rec, enable); - ftrace_addr = get_ftrace_addr(rec); + ftrace_addr = ftrace_get_addr_new(rec); switch (ret) { case FTRACE_UPDATE_IGNORE: return 0; - case FTRACE_UPDATE_MODIFY_CALL_REGS: case FTRACE_UPDATE_MODIFY_CALL: case FTRACE_UPDATE_MAKE_CALL: /* converting nop to call */ @@ -621,8 +581,8 @@ void ftrace_replace_code(int enable) return; remove_breakpoints: + pr_warn("Failed on %s (%d):\n", report, count); ftrace_bug(ret, rec ? rec->ip : 0); - printk(KERN_WARNING "Failed on %s (%d):\n", report, count); for_ftrace_rec_iter(iter) { rec = ftrace_rec_iter_record(iter); /* diff --git a/arch/x86/kernel/mcount_64.S b/arch/x86/kernel/mcount_64.S new file mode 100644 index 000000000000..c050a0153168 --- /dev/null +++ b/arch/x86/kernel/mcount_64.S @@ -0,0 +1,217 @@ +/* + * linux/arch/x86_64/mcount_64.S + * + * Copyright (C) 2014 Steven Rostedt, Red Hat Inc + */ + +#include <linux/linkage.h> +#include <asm/ptrace.h> +#include <asm/ftrace.h> + + + .code64 + .section .entry.text, "ax" + + +#ifdef CONFIG_FUNCTION_TRACER + +#ifdef CC_USING_FENTRY +# define function_hook __fentry__ +#else +# define function_hook mcount +#endif + +#ifdef CONFIG_DYNAMIC_FTRACE + +ENTRY(function_hook) + retq +END(function_hook) + +/* skip is set if stack has been adjusted */ +.macro ftrace_caller_setup skip=0 + MCOUNT_SAVE_FRAME \skip + + /* Load the ftrace_ops into the 3rd parameter */ + movq function_trace_op(%rip), %rdx + + /* Load ip into the first parameter */ + movq RIP(%rsp), %rdi + subq $MCOUNT_INSN_SIZE, %rdi + /* Load the parent_ip into the second parameter */ +#ifdef CC_USING_FENTRY + movq SS+16(%rsp), %rsi +#else + movq 8(%rbp), %rsi +#endif +.endm + +ENTRY(ftrace_caller) + /* Check if tracing was disabled (quick check) */ + cmpl $0, function_trace_stop + jne ftrace_stub + + ftrace_caller_setup + /* regs go into 4th parameter (but make it NULL) */ + movq $0, %rcx + +GLOBAL(ftrace_call) + call ftrace_stub + + MCOUNT_RESTORE_FRAME +ftrace_return: + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +GLOBAL(ftrace_graph_call) + jmp ftrace_stub +#endif + +GLOBAL(ftrace_stub) + retq +END(ftrace_caller) + +ENTRY(ftrace_regs_caller) + /* Save the current flags before compare (in SS location)*/ + pushfq + + /* Check if tracing was disabled (quick check) */ + cmpl $0, function_trace_stop + jne ftrace_restore_flags + + /* skip=8 to skip flags saved in SS */ + ftrace_caller_setup 8 + + /* Save the rest of pt_regs */ + movq %r15, R15(%rsp) + movq %r14, R14(%rsp) + movq %r13, R13(%rsp) + movq %r12, R12(%rsp) + movq %r11, R11(%rsp) + movq %r10, R10(%rsp) + movq %rbp, RBP(%rsp) + movq %rbx, RBX(%rsp) + /* Copy saved flags */ + movq SS(%rsp), %rcx + movq %rcx, EFLAGS(%rsp) + /* Kernel segments */ + movq $__KERNEL_DS, %rcx + movq %rcx, SS(%rsp) + movq $__KERNEL_CS, %rcx + movq %rcx, CS(%rsp) + /* Stack - skipping return address */ + leaq SS+16(%rsp), %rcx + movq %rcx, RSP(%rsp) + + /* regs go into 4th parameter */ + leaq (%rsp), %rcx + +GLOBAL(ftrace_regs_call) + call ftrace_stub + + /* Copy flags back to SS, to restore them */ + movq EFLAGS(%rsp), %rax + movq %rax, SS(%rsp) + + /* Handlers can change the RIP */ + movq RIP(%rsp), %rax + movq %rax, SS+8(%rsp) + + /* restore the rest of pt_regs */ + movq R15(%rsp), %r15 + movq R14(%rsp), %r14 + movq R13(%rsp), %r13 + movq R12(%rsp), %r12 + movq R10(%rsp), %r10 + movq RBP(%rsp), %rbp + movq RBX(%rsp), %rbx + + /* skip=8 to skip flags saved in SS */ + MCOUNT_RESTORE_FRAME 8 + + /* Restore flags */ + popfq + + jmp ftrace_return +ftrace_restore_flags: + popfq + jmp ftrace_stub + +END(ftrace_regs_caller) + + +#else /* ! CONFIG_DYNAMIC_FTRACE */ + +ENTRY(function_hook) + cmpl $0, function_trace_stop + jne ftrace_stub + + cmpq $ftrace_stub, ftrace_trace_function + jnz trace + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + cmpq $ftrace_stub, ftrace_graph_return + jnz ftrace_graph_caller + + cmpq $ftrace_graph_entry_stub, ftrace_graph_entry + jnz ftrace_graph_caller +#endif + +GLOBAL(ftrace_stub) + retq + +trace: + MCOUNT_SAVE_FRAME + + movq RIP(%rsp), %rdi +#ifdef CC_USING_FENTRY + movq SS+16(%rsp), %rsi +#else + movq 8(%rbp), %rsi +#endif + subq $MCOUNT_INSN_SIZE, %rdi + + call *ftrace_trace_function + + MCOUNT_RESTORE_FRAME + + jmp ftrace_stub +END(function_hook) +#endif /* CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_FUNCTION_TRACER */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +ENTRY(ftrace_graph_caller) + MCOUNT_SAVE_FRAME + +#ifdef CC_USING_FENTRY + leaq SS+16(%rsp), %rdi + movq $0, %rdx /* No framepointers needed */ +#else + leaq 8(%rbp), %rdi + movq (%rbp), %rdx +#endif + movq RIP(%rsp), %rsi + subq $MCOUNT_INSN_SIZE, %rsi + + call prepare_ftrace_return + + MCOUNT_RESTORE_FRAME + + retq +END(ftrace_graph_caller) + +GLOBAL(return_to_handler) + subq $24, %rsp + + /* Save the return values */ + movq %rax, (%rsp) + movq %rdx, 8(%rsp) + movq %rbp, %rdi + + call ftrace_return_to_handler + + movq %rax, %rdi + movq 8(%rsp), %rdx + movq (%rsp), %rax + addq $24, %rsp + jmp *%rdi +#endif |