# SPDX-License-Identifier: GPL-2.0
#
# Copyright (c) 2023 MediaTek Inc.
#
# Authors:
# Kuan-Ying Lee <[email protected]>
#
import gdb
from linux import utils, stackdepot, constants, mm
if constants.LX_CONFIG_PAGE_OWNER:
page_ext_t = utils.CachedType('struct page_ext')
page_owner_t = utils.CachedType('struct page_owner')
PAGE_OWNER_STACK_DEPTH = 16
PAGE_EXT_OWNER = constants.LX_PAGE_EXT_OWNER
PAGE_EXT_INVALID = 0x1
PAGE_EXT_OWNER_ALLOCATED = constants.LX_PAGE_EXT_OWNER_ALLOCATED
def help():
t = """Usage: lx-dump-page-owner [Option]
Option:
--pfn [Decimal pfn]
Example:
lx-dump-page-owner --pfn 655360\n"""
gdb.write("Unrecognized command\n")
raise gdb.GdbError(t)
class DumpPageOwner(gdb.Command):
"""Dump page owner"""
min_pfn = None
max_pfn = None
p_ops = None
migrate_reason_names = None
def __init__(self):
super(DumpPageOwner, self).__init__("lx-dump-page-owner", gdb.COMMAND_SUPPORT)
def invoke(self, args, from_tty):
if not constants.LX_CONFIG_PAGE_OWNER:
raise gdb.GdbError('CONFIG_PAGE_OWNER does not enable')
page_owner_inited = gdb.parse_and_eval('page_owner_inited')
if page_owner_inited['key']['enabled']['counter'] != 0x1:
raise gdb.GdbError('page_owner_inited is not enabled')
self.p_ops = mm.page_ops().ops
self.get_page_owner_info()
argv = gdb.string_to_argv(args)
if len(argv) == 0:
self.read_page_owner()
elif len(argv) == 2:
if argv[0] == "--pfn":
pfn = int(argv[1])
self.read_page_owner_by_addr(self.p_ops.pfn_to_page(pfn))
else:
help()
else:
help()
def get_page_owner_info(self):
self.min_pfn = int(gdb.parse_and_eval("min_low_pfn"))
self.max_pfn = int(gdb.parse_and_eval("max_pfn"))
self.page_ext_size = int(gdb.parse_and_eval("page_ext_size"))
self.migrate_reason_names = gdb.parse_and_eval('migrate_reason_names')
def page_ext_invalid(self, page_ext):
if page_ext == gdb.Value(0):
return True
if page_ext.cast(utils.get_ulong_type()) & PAGE_EXT_INVALID == PAGE_EXT_INVALID:
return True
return False
def get_entry(self, base, index):
return (base.cast(utils.get_ulong_type()) + self.page_ext_size * index).cast(page_ext_t.get_type().pointer())
def lookup_page_ext(self, page):
pfn = self.p_ops.page_to_pfn(page)
section = self.p_ops.pfn_to_section(pfn)
page_ext = section["page_ext"]
if self.page_ext_invalid(page_ext):
return gdb.Value(0)
return self.get_entry(page_ext, pfn)
def page_ext_get(self, page):
page_ext = self.lookup_page_ext(page)
if page_ext != gdb.Value(0):
return page_ext
else:
return gdb.Value(0)
def get_page_owner(self, page_ext):
addr = page_ext.cast(utils.get_ulong_type()) + gdb.parse_and_eval("page_owner_ops")["offset"].cast(utils.get_ulong_type())
return addr.cast(page_owner_t.get_type().pointer())
def read_page_owner_by_addr(self, struct_page_addr):
page = gdb.Value(struct_page_addr).cast(utils.get_page_type().pointer())
pfn = self.p_ops.page_to_pfn(page)
if pfn < self.min_pfn or pfn > self.max_pfn or (not self.p_ops.pfn_valid(pfn)):
gdb.write("pfn is invalid\n")
return
page = self.p_ops.pfn_to_page(pfn)
page_ext = self.page_ext_get(page)
if page_ext == gdb.Value(0):
gdb.write("page_ext is null\n")
return
if not (page_ext['flags'] & (1 << PAGE_EXT_OWNER)):
gdb.write("page_owner flag is invalid\n")
raise gdb.GdbError('page_owner info is not present (never set?)\n')
if mm.test_bit(PAGE_EXT_OWNER_ALLOCATED, page_ext['flags'].address):
gdb.write('page_owner tracks the page as allocated\n')
else:
gdb.write('page_owner tracks the page as freed\n')
if not (page_ext['flags'] & (1 << PAGE_EXT_OWNER_ALLOCATED)):
gdb.write("page_owner is not allocated\n")
page_owner = self.get_page_owner(page_ext)
gdb.write("Page last allocated via order %d, gfp_mask: 0x%x, pid: %d, tgid: %d (%s), ts %u ns, free_ts %u ns\n" %\
(page_owner["order"], page_owner["gfp_mask"],\
page_owner["pid"], page_owner["tgid"], page_owner["comm"].string(),\
page_owner["ts_nsec"], page_owner["free_ts_nsec"]))
gdb.write("PFN: %d, Flags: 0x%x\n" % (pfn, page['flags']))
if page_owner["handle"] == 0:
gdb.write('page_owner allocation stack trace missing\n')
else:
stackdepot.stack_depot_print(page_owner["handle"])
if page_owner["free_handle"] == 0:
gdb.write('page_owner free stack trace missing\n')
else:
gdb.write('page last free stack trace:\n')
stackdepot.stack_depot_print(page_owner["free_handle"])
if page_owner['last_migrate_reason'] != -1:
gdb.write('page has been migrated, last migrate reason: %s\n' % self.migrate_reason_names[page_owner['last_migrate_reason']])
def read_page_owner(self):
pfn = self.min_pfn
# Find a valid PFN or the start of a MAX_ORDER_NR_PAGES area
while ((not self.p_ops.pfn_valid(pfn)) and (pfn & (self.p_ops.MAX_ORDER_NR_PAGES - 1))) != 0:
pfn += 1
while pfn < self.max_pfn:
#
# If the new page is in a new MAX_ORDER_NR_PAGES area,
# validate the area as existing, skip it if not
#
if ((pfn & (self.p_ops.MAX_ORDER_NR_PAGES - 1)) == 0) and (not self.p_ops.pfn_valid(pfn)):
pfn += (self.p_ops.MAX_ORDER_NR_PAGES - 1)
continue;
page = self.p_ops.pfn_to_page(pfn)
page_ext = self.page_ext_get(page)
if page_ext == gdb.Value(0):
pfn += 1
continue
if not (page_ext['flags'] & (1 << PAGE_EXT_OWNER)):
pfn += 1
continue
if not (page_ext['flags'] & (1 << PAGE_EXT_OWNER_ALLOCATED)):
pfn += 1
continue
page_owner = self.get_page_owner(page_ext)
gdb.write("Page allocated via order %d, gfp_mask: 0x%x, pid: %d, tgid: %d (%s), ts %u ns, free_ts %u ns\n" %\
(page_owner["order"], page_owner["gfp_mask"],\
page_owner["pid"], page_owner["tgid"], page_owner["comm"].string(),\
page_owner["ts_nsec"], page_owner["free_ts_nsec"]))
gdb.write("PFN: %d, Flags: 0x%x\n" % (pfn, page['flags']))
stackdepot.stack_depot_print(page_owner["handle"])
pfn += (1 << page_owner["order"])
DumpPageOwner()
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