Simplify the stack retrieval code by using the storage array based interface.
Signed-off-by: Thomas Gleixner <t...@linutronix.de> --- kernel/trace/trace_stack.c | 42 ++++++++++++++++-------------------------- 1 file changed, 16 insertions(+), 26 deletions(-) --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -23,16 +23,7 @@ static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES]; static unsigned stack_trace_index[STACK_TRACE_ENTRIES]; -/* - * Reserve one entry for the passed in ip. This will allow - * us to remove most or all of the stack size overhead - * added by the stack tracer itself. - */ -struct stack_trace stack_trace_max = { - .max_entries = STACK_TRACE_ENTRIES - 1, - .entries = &stack_dump_trace[0], -}; - +static unsigned int stack_trace_entries; static unsigned long stack_trace_max_size; static arch_spinlock_t stack_trace_max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; @@ -49,10 +40,10 @@ static void print_max_stack(void) pr_emerg(" Depth Size Location (%d entries)\n" " ----- ---- --------\n", - stack_trace_max.nr_entries); + stack_trace_entries); - for (i = 0; i < stack_trace_max.nr_entries; i++) { - if (i + 1 == stack_trace_max.nr_entries) + for (i = 0; i < stack_trace_entries; i++) { + if (i + 1 == stack_trace_entries) size = stack_trace_index[i]; else size = stack_trace_index[i] - stack_trace_index[i+1]; @@ -98,13 +89,12 @@ static void check_stack(unsigned long ip stack_trace_max_size = this_size; - stack_trace_max.nr_entries = 0; - stack_trace_max.skip = 0; - - save_stack_trace(&stack_trace_max); + stack_trace_entries = stack_trace_save(stack_dump_trace, + ARRAY_SIZE(stack_dump_trace) - 1, + 0); /* Skip over the overhead of the stack tracer itself */ - for (i = 0; i < stack_trace_max.nr_entries; i++) { + for (i = 0; i < stack_trace_entries; i++) { if (stack_dump_trace[i] == ip) break; } @@ -113,7 +103,7 @@ static void check_stack(unsigned long ip * Some archs may not have the passed in ip in the dump. * If that happens, we need to show everything. */ - if (i == stack_trace_max.nr_entries) + if (i == stack_trace_entries) i = 0; /* @@ -131,13 +121,13 @@ static void check_stack(unsigned long ip * loop will only happen once. This code only takes place * on a new max, so it is far from a fast path. */ - while (i < stack_trace_max.nr_entries) { + while (i < stack_trace_entries) { int found = 0; stack_trace_index[x] = this_size; p = start; - for (; p < top && i < stack_trace_max.nr_entries; p++) { + for (; p < top && i < stack_trace_entries; p++) { /* * The READ_ONCE_NOCHECK is used to let KASAN know that * this is not a stack-out-of-bounds error. @@ -168,7 +158,7 @@ static void check_stack(unsigned long ip i++; } - stack_trace_max.nr_entries = x; + stack_trace_entries = x; if (task_stack_end_corrupted(current)) { print_max_stack(); @@ -270,7 +260,7 @@ static void * { long n = *pos - 1; - if (n >= stack_trace_max.nr_entries) + if (n >= stack_trace_entries) return NULL; m->private = (void *)n; @@ -334,7 +324,7 @@ static int t_show(struct seq_file *m, vo seq_printf(m, " Depth Size Location" " (%d entries)\n" " ----- ---- --------\n", - stack_trace_max.nr_entries); + stack_trace_entries); if (!stack_tracer_enabled && !stack_trace_max_size) print_disabled(m); @@ -344,10 +334,10 @@ static int t_show(struct seq_file *m, vo i = *(long *)v; - if (i >= stack_trace_max.nr_entries) + if (i >= stack_trace_entries) return 0; - if (i + 1 == stack_trace_max.nr_entries) + if (i + 1 == stack_trace_entries) size = stack_trace_index[i]; else size = stack_trace_index[i] - stack_trace_index[i+1]; -- dm-devel mailing list dm-devel@redhat.com https://www.redhat.com/mailman/listinfo/dm-devel