shinys000114/linux
1
0
Fork 0
mirror of https://github.com/hardkernel/linux.git synced 2026-06-06 10:58:48 +09:00
Code Issues Packages Projects Releases Wiki Activity

ANDROID: mm: Throttle rss_stat tracepoint

Browse Source 
Previously we were throttling rss_stat tracepoint by checking for 512KB
boundary cross over. We removed that because upstream suggested eBPF or
other ways. However right now, we don't have support for those. Let us
re introduce the patch to throttle and avoid large number of events
which are causing data loss.

Bug: 145972256

Change-Id: I4132133aa36163430069b3ca2f57443940fb90b3
Signed-off-by: Joel Fernandes <joelaf@google.com>
This commit is contained in:
Joel Fernandes
2019-12-10 10:45:34 -05:00
parent 5f39cd276b
commit b3ddf584b0
2 changed files with 19 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
include/linux/mm.h
View File

@@ -1646,27 +1646,28 @@ static inline unsigned long get_mm_counter(struct mm_struct *mm, int member)
return (unsigned long)val;
}
void mm_trace_rss_stat(struct mm_struct *mm, int member, long count);
void mm_trace_rss_stat(struct mm_struct *mm, int member, long count,
long value);
static inline void add_mm_counter(struct mm_struct *mm, int member, long value)
{
long count = atomic_long_add_return(value, &mm->rss_stat.count[member]);
mm_trace_rss_stat(mm, member, count);
mm_trace_rss_stat(mm, member, count, value);
}
static inline void inc_mm_counter(struct mm_struct *mm, int member)
{
long count = atomic_long_inc_return(&mm->rss_stat.count[member]);
mm_trace_rss_stat(mm, member, count);
mm_trace_rss_stat(mm, member, count, 1);
}
static inline void dec_mm_counter(struct mm_struct *mm, int member)
{
long count = atomic_long_dec_return(&mm->rss_stat.count[member]);
mm_trace_rss_stat(mm, member, count);
mm_trace_rss_stat(mm, member, count, -1);
}
/* Optimized variant when page is already known not to be PageAnon */

16
mm/memory.c
View File

@@ -140,9 +140,21 @@ static int __init init_zero_pfn(void)
}
core_initcall(init_zero_pfn);
void mm_trace_rss_stat(struct mm_struct *mm, int member, long count)
/*
* Only trace rss_stat when there is a 512kb cross over.
* Smaller changes may be lost unless every small change is
* crossing into or returning to a 512kb boundary.
*/
#define TRACE_MM_COUNTER_THRESHOLD 128
void mm_trace_rss_stat(struct mm_struct *mm, int member, long count,
long value)
{
trace_rss_stat(mm, member, count);
long thresh_mask = ~(TRACE_MM_COUNTER_THRESHOLD - 1);
/* Threshold roll-over, trace it */
if ((count & thresh_mask) != ((count - value) & thresh_mask))
trace_rss_stat(mm, member, count);
}
#if defined(SPLIT_RSS_COUNTING)