Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: lockdep: Avoid out of bounds array reference in save_trace() futex: Take mmap_sem for get_user_pages in fault_in_user_writeable lockstat: Add usage info to Documentation/lockstat.txt lockstat: Fix min, max times in /proc/lock_stats
This commit is contained in:
commit
1e57c2186f
|
@ -62,8 +62,20 @@ applicable).
|
|||
It also tracks 4 contention points per class. A contention point is a call site
|
||||
that had to wait on lock acquisition.
|
||||
|
||||
- CONFIGURATION
|
||||
|
||||
Lock statistics are enabled via CONFIG_LOCK_STATS.
|
||||
|
||||
- USAGE
|
||||
|
||||
Enable collection of statistics:
|
||||
|
||||
# echo 1 >/proc/sys/kernel/lock_stat
|
||||
|
||||
Disable collection of statistics:
|
||||
|
||||
# echo 0 >/proc/sys/kernel/lock_stat
|
||||
|
||||
Look at the current lock statistics:
|
||||
|
||||
( line numbers not part of actual output, done for clarity in the explanation
|
||||
|
|
|
@ -304,8 +304,14 @@ void put_futex_key(int fshared, union futex_key *key)
|
|||
*/
|
||||
static int fault_in_user_writeable(u32 __user *uaddr)
|
||||
{
|
||||
int ret = get_user_pages(current, current->mm, (unsigned long)uaddr,
|
||||
1, 1, 0, NULL, NULL);
|
||||
struct mm_struct *mm = current->mm;
|
||||
int ret;
|
||||
|
||||
down_read(&mm->mmap_sem);
|
||||
ret = get_user_pages(current, mm, (unsigned long)uaddr,
|
||||
1, 1, 0, NULL, NULL);
|
||||
up_read(&mm->mmap_sem);
|
||||
|
||||
return ret < 0 ? ret : 0;
|
||||
}
|
||||
|
||||
|
|
|
@ -168,7 +168,7 @@ static void lock_time_inc(struct lock_time *lt, u64 time)
|
|||
if (time > lt->max)
|
||||
lt->max = time;
|
||||
|
||||
if (time < lt->min || !lt->min)
|
||||
if (time < lt->min || !lt->nr)
|
||||
lt->min = time;
|
||||
|
||||
lt->total += time;
|
||||
|
@ -177,8 +177,15 @@ static void lock_time_inc(struct lock_time *lt, u64 time)
|
|||
|
||||
static inline void lock_time_add(struct lock_time *src, struct lock_time *dst)
|
||||
{
|
||||
dst->min += src->min;
|
||||
dst->max += src->max;
|
||||
if (!src->nr)
|
||||
return;
|
||||
|
||||
if (src->max > dst->max)
|
||||
dst->max = src->max;
|
||||
|
||||
if (src->min < dst->min || !dst->nr)
|
||||
dst->min = src->min;
|
||||
|
||||
dst->total += src->total;
|
||||
dst->nr += src->nr;
|
||||
}
|
||||
|
@ -379,7 +386,8 @@ static int save_trace(struct stack_trace *trace)
|
|||
* complete trace that maxes out the entries provided will be reported
|
||||
* as incomplete, friggin useless </rant>
|
||||
*/
|
||||
if (trace->entries[trace->nr_entries-1] == ULONG_MAX)
|
||||
if (trace->nr_entries != 0 &&
|
||||
trace->entries[trace->nr_entries-1] == ULONG_MAX)
|
||||
trace->nr_entries--;
|
||||
|
||||
trace->max_entries = trace->nr_entries;
|
||||
|
|
Loading…
Reference in a new issue