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author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-01-28 08:33:08 +0100 |
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committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-05-02 13:54:11 +0200 |
commit | 78c98f9074135d3dab4e39544e0a537f92388fce (patch) | |
tree | 6f6d96e8e0911fe2aa27ec89cca52d56d3ed6f7e /arch/s390/oprofile | |
parent | 1c705ad5efae9c712e763a47fbcc95b87b7347d2 (diff) | |
download | linux-78c98f9074135d3dab4e39544e0a537f92388fce.tar.bz2 |
s390/unwind: introduce stack unwind API
Rework the dump_trace() stack unwinder interface to support different
unwinding algorithms. The new interface looks like this:
struct unwind_state state;
unwind_for_each_frame(&state, task, regs, start_stack)
do_something(state.sp, state.ip, state.reliable);
The unwind_bc.c file contains the implementation for the classic
back-chain unwinder.
One positive side effect of the new code is it now handles ftraced
functions gracefully. It prints the real name of the return function
instead of 'return_to_handler'.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/oprofile')
-rw-r--r-- | arch/s390/oprofile/init.c | 22 |
1 files changed, 8 insertions, 14 deletions
diff --git a/arch/s390/oprofile/init.c b/arch/s390/oprofile/init.c index 43d9525c36fc..7441857df51b 100644 --- a/arch/s390/oprofile/init.c +++ b/arch/s390/oprofile/init.c @@ -13,23 +13,17 @@ #include <linux/oprofile.h> #include <linux/init.h> #include <asm/processor.h> - -static int __s390_backtrace(void *data, unsigned long address, int reliable) -{ - unsigned int *depth = data; - - if (*depth == 0) - return 1; - (*depth)--; - oprofile_add_trace(address); - return 0; -} +#include <asm/unwind.h> static void s390_backtrace(struct pt_regs *regs, unsigned int depth) { - if (user_mode(regs)) - return; - dump_trace(__s390_backtrace, &depth, NULL, regs->gprs[15]); + struct unwind_state state; + + unwind_for_each_frame(&state, current, regs, 0) { + if (depth-- == 0) + break; + oprofile_add_trace(state.ip); + } } int __init oprofile_arch_init(struct oprofile_operations *ops) |