From 3d4cd9c94191f60cbb741cfbaa770d442c4680aa Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Tue, 17 Feb 2015 13:47:27 -0800 Subject: [PATCH] scripts/gdb: add class to iterate over CPU masks Will be used first to count module references. It is optimized to read the mask only once per stop. Signed-off-by: Jan Kiszka Cc: Thomas Gleixner Cc: Jason Wessel Cc: Andi Kleen Cc: Ben Widawsky Cc: Borislav Petkov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- scripts/gdb/linux/cpus.py | 54 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) diff --git a/scripts/gdb/linux/cpus.py b/scripts/gdb/linux/cpus.py index b683da92f194..c1441f23c0c2 100644 --- a/scripts/gdb/linux/cpus.py +++ b/scripts/gdb/linux/cpus.py @@ -50,6 +50,60 @@ def per_cpu(var_ptr, cpu): return pointer.cast(var_ptr.type).dereference() +cpu_mask = {} + + +def cpu_mask_invalidate(event): + global cpu_mask + cpu_mask = {} + gdb.events.stop.disconnect(cpu_mask_invalidate) + if hasattr(gdb.events, 'new_objfile'): + gdb.events.new_objfile.disconnect(cpu_mask_invalidate) + + +class CpuList(): + def __init__(self, mask_name): + global cpu_mask + self.mask = None + if mask_name in cpu_mask: + self.mask = cpu_mask[mask_name] + if self.mask is None: + self.mask = gdb.parse_and_eval(mask_name + ".bits") + if hasattr(gdb, 'events'): + cpu_mask[mask_name] = self.mask + gdb.events.stop.connect(cpu_mask_invalidate) + if hasattr(gdb.events, 'new_objfile'): + gdb.events.new_objfile.connect(cpu_mask_invalidate) + self.bits_per_entry = self.mask[0].type.sizeof * 8 + self.num_entries = self.mask.type.sizeof * 8 / self.bits_per_entry + self.entry = -1 + self.bits = 0 + + def __iter__(self): + return self + + def next(self): + while self.bits == 0: + self.entry += 1 + if self.entry == self.num_entries: + raise StopIteration + self.bits = self.mask[self.entry] + if self.bits != 0: + self.bit = 0 + break + + while self.bits & 1 == 0: + self.bits >>= 1 + self.bit += 1 + + cpu = self.entry * self.bits_per_entry + self.bit + + self.bits >>= 1 + self.bit += 1 + + return cpu + + class PerCpu(gdb.Function): """Return per-cpu variable.