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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/x86/oprofile/backtrace.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/x86/oprofile/backtrace.c')
-rw-r--r-- | kernel/arch/x86/oprofile/backtrace.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/kernel/arch/x86/oprofile/backtrace.c b/kernel/arch/x86/oprofile/backtrace.c new file mode 100644 index 000000000..4e664bdb5 --- /dev/null +++ b/kernel/arch/x86/oprofile/backtrace.c @@ -0,0 +1,127 @@ +/** + * @file backtrace.c + * + * @remark Copyright 2002 OProfile authors + * @remark Read the file COPYING + * + * @author John Levon + * @author David Smith + */ + +#include <linux/oprofile.h> +#include <linux/sched.h> +#include <linux/mm.h> +#include <linux/compat.h> +#include <linux/uaccess.h> + +#include <asm/ptrace.h> +#include <asm/stacktrace.h> + +static int backtrace_stack(void *data, char *name) +{ + /* Yes, we want all stacks */ + return 0; +} + +static void backtrace_address(void *data, unsigned long addr, int reliable) +{ + unsigned int *depth = data; + + if ((*depth)--) + oprofile_add_trace(addr); +} + +static struct stacktrace_ops backtrace_ops = { + .stack = backtrace_stack, + .address = backtrace_address, + .walk_stack = print_context_stack, +}; + +#ifdef CONFIG_COMPAT +static struct stack_frame_ia32 * +dump_user_backtrace_32(struct stack_frame_ia32 *head) +{ + /* Also check accessibility of one struct frame_head beyond: */ + struct stack_frame_ia32 bufhead[2]; + struct stack_frame_ia32 *fp; + unsigned long bytes; + + bytes = copy_from_user_nmi(bufhead, head, sizeof(bufhead)); + if (bytes != 0) + return NULL; + + fp = (struct stack_frame_ia32 *) compat_ptr(bufhead[0].next_frame); + + oprofile_add_trace(bufhead[0].return_address); + + /* frame pointers should strictly progress back up the stack + * (towards higher addresses) */ + if (head >= fp) + return NULL; + + return fp; +} + +static inline int +x86_backtrace_32(struct pt_regs * const regs, unsigned int depth) +{ + struct stack_frame_ia32 *head; + + /* User process is IA32 */ + if (!current || !test_thread_flag(TIF_IA32)) + return 0; + + head = (struct stack_frame_ia32 *) regs->bp; + while (depth-- && head) + head = dump_user_backtrace_32(head); + + return 1; +} + +#else +static inline int +x86_backtrace_32(struct pt_regs * const regs, unsigned int depth) +{ + return 0; +} +#endif /* CONFIG_COMPAT */ + +static struct stack_frame *dump_user_backtrace(struct stack_frame *head) +{ + /* Also check accessibility of one struct frame_head beyond: */ + struct stack_frame bufhead[2]; + unsigned long bytes; + + bytes = copy_from_user_nmi(bufhead, head, sizeof(bufhead)); + if (bytes != 0) + return NULL; + + oprofile_add_trace(bufhead[0].return_address); + + /* frame pointers should strictly progress back up the stack + * (towards higher addresses) */ + if (head >= bufhead[0].next_frame) + return NULL; + + return bufhead[0].next_frame; +} + +void +x86_backtrace(struct pt_regs * const regs, unsigned int depth) +{ + struct stack_frame *head = (struct stack_frame *)frame_pointer(regs); + + if (!user_mode(regs)) { + unsigned long stack = kernel_stack_pointer(regs); + if (depth) + dump_trace(NULL, regs, (unsigned long *)stack, 0, + &backtrace_ops, &depth); + return; + } + + if (x86_backtrace_32(regs, depth)) + return; + + while (depth-- && head) + head = dump_user_backtrace(head); +} |