mm: use stack_depot for recording kmemleak's backtrace

Using stack_depot to record kmemleak's backtrace which has been
implemented on slub for reducing redundant information.

[akpm@linux-foundation.org: fix build - remove now-unused __save_stack_trace()]
[zhaoyang.huang@unisoc.com: v3]
  Link: https://lkml.kernel.org/r/1667101354-4669-1-git-send-email-zhaoyang.huang@unisoc.com
[akpm@linux-foundation.org: fix v3 layout oddities]
[akpm@linux-foundation.org: coding-style cleanups]
Link: https://lkml.kernel.org/r/1666864224-27541-1-git-send-email-zhaoyang.huang@unisoc.com
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: ke.wang <ke.wang@unisoc.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zhaoyang Huang <huangzhaoyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Zhaoyang Huang 2022-10-27 17:50:24 +08:00 committed by Andrew Morton
parent 9102b78b6f
commit 56a61617dd
2 changed files with 29 additions and 18 deletions

View File

@ -728,6 +728,7 @@ config DEBUG_KMEMLEAK
select STACKTRACE if STACKTRACE_SUPPORT
select KALLSYMS
select CRC32
select STACKDEPOT
help
Say Y here if you want to enable the memory leak
detector. The memory allocation/freeing is traced in a way

View File

@ -79,6 +79,7 @@
#include <linux/mutex.h>
#include <linux/rcupdate.h>
#include <linux/stacktrace.h>
#include <linux/stackdepot.h>
#include <linux/cache.h>
#include <linux/percpu.h>
#include <linux/memblock.h>
@ -159,8 +160,7 @@ struct kmemleak_object {
u32 checksum;
/* memory ranges to be scanned inside an object (empty for all) */
struct hlist_head area_list;
unsigned long trace[MAX_TRACE];
unsigned int trace_len;
depot_stack_handle_t trace_handle;
unsigned long jiffies; /* creation timestamp */
pid_t pid; /* pid of the current task */
char comm[TASK_COMM_LEN]; /* executable name */
@ -346,18 +346,21 @@ static void print_unreferenced(struct seq_file *seq,
struct kmemleak_object *object)
{
int i;
unsigned long *entries;
unsigned int nr_entries;
unsigned int msecs_age = jiffies_to_msecs(jiffies - object->jiffies);
nr_entries = stack_depot_fetch(object->trace_handle, &entries);
warn_or_seq_printf(seq, "unreferenced object 0x%08lx (size %zu):\n",
object->pointer, object->size);
object->pointer, object->size);
warn_or_seq_printf(seq, " comm \"%s\", pid %d, jiffies %lu (age %d.%03ds)\n",
object->comm, object->pid, object->jiffies,
msecs_age / 1000, msecs_age % 1000);
object->comm, object->pid, object->jiffies,
msecs_age / 1000, msecs_age % 1000);
hex_dump_object(seq, object);
warn_or_seq_printf(seq, " backtrace:\n");
for (i = 0; i < object->trace_len; i++) {
void *ptr = (void *)object->trace[i];
for (i = 0; i < nr_entries; i++) {
void *ptr = (void *)entries[i];
warn_or_seq_printf(seq, " [<%p>] %pS\n", ptr, ptr);
}
}
@ -370,15 +373,16 @@ static void print_unreferenced(struct seq_file *seq,
static void dump_object_info(struct kmemleak_object *object)
{
pr_notice("Object 0x%08lx (size %zu):\n",
object->pointer, object->size);
object->pointer, object->size);
pr_notice(" comm \"%s\", pid %d, jiffies %lu\n",
object->comm, object->pid, object->jiffies);
object->comm, object->pid, object->jiffies);
pr_notice(" min_count = %d\n", object->min_count);
pr_notice(" count = %d\n", object->count);
pr_notice(" flags = 0x%x\n", object->flags);
pr_notice(" checksum = %u\n", object->checksum);
pr_notice(" backtrace:\n");
stack_trace_print(object->trace, object->trace_len, 4);
if (object->trace_handle)
stack_depot_print(object->trace_handle);
}
/*
@ -591,12 +595,18 @@ static struct kmemleak_object *find_and_remove_object(unsigned long ptr, int ali
return object;
}
/*
* Save stack trace to the given array of MAX_TRACE size.
*/
static int __save_stack_trace(unsigned long *trace)
static noinline depot_stack_handle_t set_track_prepare(void)
{
return stack_trace_save(trace, MAX_TRACE, 2);
depot_stack_handle_t trace_handle;
unsigned long entries[MAX_TRACE];
unsigned int nr_entries;
if (!kmemleak_initialized)
return 0;
nr_entries = stack_trace_save(entries, ARRAY_SIZE(entries), 3);
trace_handle = stack_depot_save(entries, nr_entries, GFP_NOWAIT);
return trace_handle;
}
/*
@ -653,7 +663,7 @@ static void __create_object(unsigned long ptr, size_t size,
}
/* kernel backtrace */
object->trace_len = __save_stack_trace(object->trace);
object->trace_handle = set_track_prepare();
raw_spin_lock_irqsave(&kmemleak_lock, flags);
@ -692,7 +702,6 @@ static void __create_object(unsigned long ptr, size_t size,
rb_link_node(&object->rb_node, rb_parent, link);
rb_insert_color(&object->rb_node, is_phys ? &object_phys_tree_root :
&object_tree_root);
list_add_tail_rcu(&object->object_list, &object_list);
out:
raw_spin_unlock_irqrestore(&kmemleak_lock, flags);
@ -1091,7 +1100,7 @@ void __ref kmemleak_update_trace(const void *ptr)
}
raw_spin_lock_irqsave(&object->lock, flags);
object->trace_len = __save_stack_trace(object->trace);
object->trace_handle = set_track_prepare();
raw_spin_unlock_irqrestore(&object->lock, flags);
put_object(object);
@ -2084,6 +2093,7 @@ void __init kmemleak_init(void)
if (kmemleak_error)
return;
stack_depot_init();
jiffies_min_age = msecs_to_jiffies(MSECS_MIN_AGE);
jiffies_scan_wait = msecs_to_jiffies(SECS_SCAN_WAIT * 1000);