From 7ad3f188aac15772c97523dc4ca3e8e5b6294b9c Mon Sep 17 00:00:00 2001 From: Yang Shi Date: Wed, 15 Nov 2017 17:31:59 -0800 Subject: tools: slabinfo: add "-U" option to show unreclaimable slabs only Patch series "oom: capture unreclaimable slab info in oom message", v10. Recently we ran into a oom issue, kernel panic due to no killable process. The dmesg shows huge unreclaimable slabs used almost 100% memory, but kdump doesn't capture vmcore due to some reason. So, it may sound better to capture unreclaimable slab info in oom message when kernel panic to aid trouble shooting and cover the corner case. Since kernel already panic, so capturing more information sounds worthy and doesn't bother normal oom killer. With the patchset, tools/vm/slabinfo has a new option, "-U", to show unreclaimable slab only. And, oom will print all non zero (num_objs * size != 0) unreclaimable slabs in oom killer message. This patch (of 3): Add "-U" option to show unreclaimable slabs only. "-U" and "-S" together can tell us what unreclaimable slabs use the most memory to help debug huge unreclaimable slabs issue. Link: http://lkml.kernel.org/r/1507152550-46205-2-git-send-email-yang.s@alibaba-inc.com Signed-off-by: Yang Shi Acked-by: Christoph Lameter Acked-by: David Rientjes Cc: Pekka Enberg Cc: Joonsoo Kim Cc: Michal Hocko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/vm/slabinfo.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'tools') diff --git a/tools/vm/slabinfo.c b/tools/vm/slabinfo.c index b0b7ef6d0de1..f82c2eaa859d 100644 --- a/tools/vm/slabinfo.c +++ b/tools/vm/slabinfo.c @@ -84,6 +84,7 @@ int output_lines = -1; int sort_loss; int extended_totals; int show_bytes; +int unreclaim_only; /* Debug options */ int sanity; @@ -133,6 +134,7 @@ static void usage(void) "-L|--Loss Sort by loss\n" "-X|--Xtotals Show extended summary information\n" "-B|--Bytes Show size in bytes\n" + "-U|--Unreclaim Show unreclaimable slabs only\n" "\nValid debug options (FZPUT may be combined)\n" "a / A Switch on all debug options (=FZUP)\n" "- Switch off all debug options\n" @@ -569,6 +571,9 @@ static void slabcache(struct slabinfo *s) if (strcmp(s->name, "*") == 0) return; + if (unreclaim_only && s->reclaim_account) + return; + if (actual_slabs == 1) { report(s); return; @@ -1347,6 +1352,7 @@ struct option opts[] = { { "Loss", no_argument, NULL, 'L'}, { "Xtotals", no_argument, NULL, 'X'}, { "Bytes", no_argument, NULL, 'B'}, + { "Unreclaim", no_argument, NULL, 'U'}, { NULL, 0, NULL, 0 } }; @@ -1358,7 +1364,7 @@ int main(int argc, char *argv[]) page_size = getpagesize(); - while ((c = getopt_long(argc, argv, "aAd::Defhil1noprstvzTSN:LXB", + while ((c = getopt_long(argc, argv, "aAd::Defhil1noprstvzTSN:LXBU", opts, NULL)) != -1) switch (c) { case '1': @@ -1439,6 +1445,9 @@ int main(int argc, char *argv[]) case 'B': show_bytes = 1; break; + case 'U': + unreclaim_only = 1; + break; default: fatal("%s: Invalid option '%c'\n", argv[0], optopt); -- cgit v1.2.3-59-g8ed1b