From: Yinan Zhang zhangyinan2019@email.szu.edu.cn
mainline inclusion from mainline-v5.18-rc1 commit cd75ea0e32620c622aeaef531ef7b9f59c67f7a6 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9GSSR
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Culling by comparing stacktrace would casue loss of some information. For example, if there exists 2 blocks which have the same stacktrace and the different head info
Page allocated via order 0, mask 0x108c48(...), pid 73696, ts 1578829190639010 ns, free_ts 1576583851324450 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8
Page allocated via order 0, mask 0x108c48(...), pid 61806, ts 1354113726046100 ns, free_ts 1354104926841400 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8
After culling, it would be like this
2 times, 2 pages: Page allocated via order 0, mask 0x108c48(...), pid 73696, ts 1578829190639010 ns, free_ts 1576583851324450 ns prep_new_page+0x80/0xb8 get_page_from_freelist+0x924/0xee8 __alloc_pages+0x138/0xc18 alloc_pages+0x80/0xf0 __page_cache_alloc+0x90/0xc8
The info of second block missed. So, add -c to turn on culling by stacktrace. By default, it will cull by txt.
Link: https://lkml.kernel.org/r/20211129145658.2491-1-zhangyinan2019@email.szu.edu... Signed-off-by: Yinan Zhang zhangyinan2019@email.szu.edu.cn Cc: Changhee Han ch0.han@lge.com Cc: Sean Anderson seanga2@gmail.com Cc: Stephen Rothwell sfr@canb.auug.org.au Cc: Tang Bin tangbin@cmss.chinamobile.com Cc: Zhang Shengju zhangshengju@cmss.chinamobile.com Cc: Zhenliang Wei weizhenliang@huawei.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Jinjiang Tu tujinjiang@huawei.com --- tools/vm/page_owner_sort.c | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-)
diff --git a/tools/vm/page_owner_sort.c b/tools/vm/page_owner_sort.c index 1b2acf02d3cd..492be7f752c0 100644 --- a/tools/vm/page_owner_sort.c +++ b/tools/vm/page_owner_sort.c @@ -51,6 +51,13 @@ int read_block(char *buf, int buf_size, FILE *fin) return -1; /* EOF or no space left in buf. */ }
+static int compare_txt(const void *p1, const void *p2) +{ + const struct block_list *l1 = p1, *l2 = p2; + + return strcmp(l1->txt, l2->txt); +} + static int compare_stacktrace(const void *p1, const void *p2) { const struct block_list *l1 = p1, *l2 = p2; @@ -137,12 +144,14 @@ static void usage(void) "-m Sort by total memory.\n" "-s Sort by the stack trace.\n" "-t Sort by times (default).\n" + "-c cull by comparing stacktrace instead of total block.\n" ); }
int main(int argc, char **argv) { int (*cmp)(const void *, const void *) = compare_num; + int cull_st = 0; FILE *fin, *fout; char *buf; int ret, i, count; @@ -151,7 +160,7 @@ int main(int argc, char **argv) int err; int opt;
- while ((opt = getopt(argc, argv, "mst")) != -1) + while ((opt = getopt(argc, argv, "mstc")) != -1) switch (opt) { case 'm': cmp = compare_page_num; @@ -162,6 +171,9 @@ int main(int argc, char **argv) case 't': cmp = compare_num; break; + case 'c': + cull_st = 1; + break; default: usage(); exit(1); @@ -209,7 +221,10 @@ int main(int argc, char **argv)
printf("sorting ....\n");
- qsort(list, list_size, sizeof(list[0]), compare_stacktrace); + if (cull_st == 1) + qsort(list, list_size, sizeof(list[0]), compare_stacktrace); + else + qsort(list, list_size, sizeof(list[0]), compare_txt);
list2 = malloc(sizeof(*list) * list_size); if (!list2) { @@ -219,9 +234,11 @@ int main(int argc, char **argv)
printf("culling\n");
+ long offset = cull_st ? &list[0].stacktrace - &list[0].txt : 0; + for (i = count = 0; i < list_size; i++) { if (count == 0 || - strcmp(list2[count-1].stacktrace, list[i].stacktrace) != 0) { + strcmp(*(&list2[count-1].txt+offset), *(&list[i].txt+offset)) != 0) { list2[count++] = list[i]; } else { list2[count-1].num += list[i].num;