[Crash-utility] [PATCH RFC] Add "kmem -r" to display accumulated slab statistics like /proc/slabinfo
Kazuhito Hagio
k-hagio at ab.jp.nec.com
Thu Aug 23 20:11:22 UTC 2018
Nowadays, the "kmem -s" output can become very long vertically too,
due to the memcg kmem caches. It look like the longer a system has
run, the longer it becomes.
crash> kmem -s | wc -l
19855
On the other hand, since /proc/slabinfo accumulates the values of
each slab_root_caches and its children, it's still short relatively.
And I think there are many cases that support folks want to see the
accumulated values like /proc/slabinfo from vmcore, in order to
grasp the overview of slab activity quickly.
We can use something like the attached script to accumulate them,
but I believe it would be more useful to implement it in crash.
This patch introduces the "kmem -r" option to imitate /proc/slabinfo,
but it is limited to CONFIG_SLUB for now.
I tested this patch with the kmem-s2r.awk script:
crash> kmem -s | awk -f kmem-s2r.awk > kmem-s2r.txt
crash> kmem -r > kmem-r.txt
# diff -u kmem-s2r.txt kmem-r.txt
Supported:
crash> kmem -r
crash> kmem -r list
crash> kmem -r <slab name>
Signed-off-by: Kazuhito Hagio <k-hagio at ab.jp.nec.com>
---
defs.h | 5 ++
help.c | 10 +--
memory.c | 219 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++------
symbols.c | 9 +++
4 files changed, 220 insertions(+), 23 deletions(-)
diff --git a/defs.h b/defs.h
index 6fdb478..8687ff1 100644
--- a/defs.h
+++ b/defs.h
@@ -2032,6 +2032,10 @@ struct offset_table { /* stash of commonly-used offsets */
long bpf_prog_aux_user;
long user_struct_uid;
long idr_cur;
+ long kmem_cache_memcg_params;
+ long memcg_cache_params___root_caches_node;
+ long memcg_cache_params_children;
+ long memcg_cache_params_children_node;
};
struct size_table { /* stash of commonly-used sizes */
@@ -2438,6 +2442,7 @@ struct vm_table { /* kernel VM-related data */
#define PAGEFLAGS (0x4000000)
#define SLAB_OVERLOAD_PAGE (0x8000000)
#define SLAB_CPU_CACHE (0x10000000)
+#define SLAB_ROOT_CACHES (0x20000000)
#define IS_FLATMEM() (vt->flags & FLATMEM)
#define IS_DISCONTIGMEM() (vt->flags & DISCONTIGMEM)
diff --git a/help.c b/help.c
index aeeb056..ee8b999 100644
--- a/help.c
+++ b/help.c
@@ -6448,7 +6448,7 @@ char *help_kmem[] = {
"kmem",
"kernel memory",
"[-f|-F|-c|-C|-i|-v|-V|-n|-z|-o|-h] [-p | -m member[,member]]\n"
-" [[-s|-S] [slab] [-I slab[,slab]]] [-g [flags]] [[-P] address]]",
+" [[-s|-S|-r] [slab] [-I slab[,slab]]] [-g [flags]] [[-P] address]]",
" This command displays information about the use of kernel memory.\n",
" -f displays the contents of the system free memory headers.",
" also verifies that the page count equals nr_free_pages.",
@@ -6490,10 +6490,12 @@ char *help_kmem[] = {
" slab data for each per-cpu slab is displayed, along with the",
" address of each kmem_cache_node, its count of full and partial",
" slabs, and a list of all tracked slabs.",
-" slab when used with -s or -S, limits the command to only the slab cache",
-" of name \"slab\". If the slab argument is \"list\", then",
+" -r displays accumulated kmalloc() slab data of each slab_root_caches",
+" and its children. Available only if CONFIG_SLUB for now.",
+" slab when used with -s, -S or -r, limits the command to only the slab",
+" cache of name \"slab\". If the slab argument is \"list\", then",
" all slab cache names and addresses are listed.",
-" -I slab when used with -s or -S, one or more slab cache names in a",
+" -I slab when used with -s, -S or -r, one or more slab cache names in a",
" comma-separated list may be specified as slab caches to ignore.",
" -g displays the enumerator value of all bits in the page structure's",
" \"flags\" field.",
diff --git a/memory.c b/memory.c
index e02ba68..1501b21 100644
--- a/memory.c
+++ b/memory.c
@@ -167,12 +167,12 @@ static int kmem_cache_downsize(void);
static int ignore_cache(struct meminfo *, char *);
static char *is_kmem_cache_addr(ulong, char *);
static char *is_kmem_cache_addr_common(ulong, char *);
-static void kmem_cache_list(void);
+static void kmem_cache_list(struct meminfo *);
static void dump_kmem_cache(struct meminfo *);
static void dump_kmem_cache_percpu_v1(struct meminfo *);
static void dump_kmem_cache_percpu_v2(struct meminfo *);
static void dump_kmem_cache_slub(struct meminfo *);
-static void kmem_cache_list_common(void);
+static void kmem_cache_list_common(struct meminfo *);
static ulong get_cpu_slab_ptr(struct meminfo *, int, ulong *);
static unsigned int oo_order(ulong);
static unsigned int oo_objects(ulong);
@@ -276,6 +276,8 @@ static int generic_read_dumpfile(ulonglong, void *, long, char *, ulong);
static int generic_write_dumpfile(ulonglong, void *, long, char *, ulong);
static int page_to_nid(ulong);
static int get_kmem_cache_list(ulong **);
+static int get_kmem_cache_root_list(ulong **);
+static int get_kmem_cache_child_list(ulong **, ulong);
static int get_kmem_cache_slub_data(long, struct meminfo *);
static ulong compound_head(ulong);
static long count_partial(ulong, struct meminfo *, ulong *);
@@ -815,6 +817,23 @@ vm_init(void)
"kmem_slab_s", "s_magic");
}
+ if (kernel_symbol_exists("slab_root_caches")) {
+ MEMBER_OFFSET_INIT(kmem_cache_memcg_params,
+ "kmem_cache", "memcg_params");
+ MEMBER_OFFSET_INIT(memcg_cache_params___root_caches_node,
+ "memcg_cache_params", "__root_caches_node");
+ MEMBER_OFFSET_INIT(memcg_cache_params_children,
+ "memcg_cache_params", "children");
+ MEMBER_OFFSET_INIT(memcg_cache_params_children_node,
+ "memcg_cache_params", "children_node");
+
+ if (VALID_MEMBER(kmem_cache_memcg_params)
+ && VALID_MEMBER(memcg_cache_params___root_caches_node)
+ && VALID_MEMBER(memcg_cache_params_children)
+ && VALID_MEMBER(memcg_cache_params_children_node))
+ vt->flags |= SLAB_ROOT_CACHES;
+ }
+
if (!kt->kernel_NR_CPUS) {
if (enumerator_value("WORK_CPU_UNBOUND", (long *)&value1))
kt->kernel_NR_CPUS = (int)value1;
@@ -4713,6 +4732,7 @@ get_task_mem_usage(ulong task, struct task_mem_usage *tm)
#define SLAB_OVERLOAD_PAGE_PTR (ADDRESS_SPECIFIED << 24)
#define SLAB_BITFIELD (ADDRESS_SPECIFIED << 25)
#define SLAB_GATHER_FAILURE (ADDRESS_SPECIFIED << 26)
+#define GET_SLAB_ROOT_CACHES (ADDRESS_SPECIFIED << 27)
#define GET_ALL \
(GET_SHARED_PAGES|GET_TOTALRAM_PAGES|GET_BUFFERS_PAGES|GET_SLAB_PAGES)
@@ -4724,6 +4744,7 @@ cmd_kmem(void)
int c;
int sflag, Sflag, pflag, fflag, Fflag, vflag, zflag, oflag, gflag;
int nflag, cflag, Cflag, iflag, lflag, Lflag, Pflag, Vflag, hflag;
+ int rflag;
struct meminfo meminfo;
ulonglong value[MAXARGS];
char buf[BUFSIZE];
@@ -4733,13 +4754,13 @@ cmd_kmem(void)
spec_addr = 0;
sflag = Sflag = pflag = fflag = Fflag = Pflag = zflag = oflag = 0;
vflag = Cflag = cflag = iflag = nflag = lflag = Lflag = Vflag = 0;
- gflag = hflag = 0;
+ gflag = hflag = rflag = 0;
escape = FALSE;
BZERO(&meminfo, sizeof(struct meminfo));
BZERO(&value[0], sizeof(ulonglong)*MAXARGS);
pc->curcmd_flags &= ~HEADER_PRINTED;
- while ((c = getopt(argcnt, args, "gI:sSFfm:pvczCinl:L:PVoh")) != EOF) {
+ while ((c = getopt(argcnt, args, "gI:sSrFfm:pvczCinl:L:PVoh")) != EOF) {
switch(c)
{
case 'V':
@@ -4775,11 +4796,15 @@ cmd_kmem(void)
break;
case 's':
- sflag = 1; Sflag = 0;
+ sflag = 1; Sflag = rflag = 0;
break;
case 'S':
- Sflag = 1; sflag = 0;
+ Sflag = 1; sflag = rflag = 0;
+ break;
+
+ case 'r':
+ rflag = 1; sflag = Sflag = 0;
break;
case 'F':
@@ -4859,12 +4884,13 @@ cmd_kmem(void)
cmd_usage(pc->curcmd, SYNOPSIS);
if ((sflag + Sflag + pflag + fflag + Fflag + Vflag + oflag +
- vflag + Cflag + cflag + iflag + lflag + Lflag + gflag + hflag) > 1) {
+ vflag + Cflag + cflag + iflag + lflag + Lflag + gflag +
+ hflag + rflag) > 1) {
error(INFO, "only one flag allowed!\n");
cmd_usage(pc->curcmd, SYNOPSIS);
}
- if (sflag || Sflag || !(vt->flags & KMEM_CACHE_INIT))
+ if (sflag || Sflag || rflag || !(vt->flags & KMEM_CACHE_INIT))
kmem_cache_init();
while (args[optind]) {
@@ -4881,7 +4907,7 @@ cmd_kmem(void)
escape = TRUE;
} else
meminfo.reqname = args[optind];
- if (!sflag && !Sflag)
+ if (!sflag && !Sflag && !rflag)
cmd_usage(pc->curcmd, SYNOPSIS);
}
@@ -4994,7 +5020,7 @@ cmd_kmem(void)
* no value arguments allowed!
*/
if (zflag || nflag || iflag || Fflag || Cflag || Lflag ||
- Vflag || oflag || hflag) {
+ Vflag || oflag || hflag || rflag) {
error(INFO,
"no address arguments allowed with this option\n");
cmd_usage(pc->curcmd, SYNOPSIS);
@@ -5030,9 +5056,17 @@ cmd_kmem(void)
if (hflag == 1)
dump_hstates();
- if (sflag == 1) {
+ if (sflag == 1 || rflag == 1) {
+ if (rflag) {
+ if (!((vt->flags & KMALLOC_SLUB)
+ && (vt->flags & SLAB_ROOT_CACHES)))
+ error(FATAL,
+ "-r option doesn't support this kernel\n");
+
+ meminfo.flags = GET_SLAB_ROOT_CACHES;
+ }
if (!escape && STREQ(meminfo.reqname, "list"))
- kmem_cache_list();
+ kmem_cache_list(&meminfo);
else if (vt->flags & KMEM_CACHE_UNAVAIL)
error(FATAL,
"kmem cache slab subsystem not available\n");
@@ -5042,7 +5076,7 @@ cmd_kmem(void)
if (Sflag == 1) {
if (STREQ(meminfo.reqname, "list"))
- kmem_cache_list();
+ kmem_cache_list(&meminfo);
else if (vt->flags & KMEM_CACHE_UNAVAIL)
error(FATAL,
"kmem cache slab subsystem not available\n");
@@ -5092,7 +5126,8 @@ cmd_kmem(void)
if (!(sflag + Sflag + pflag + fflag + Fflag + vflag +
Vflag + zflag + oflag + cflag + Cflag + iflag +
- nflag + lflag + Lflag + gflag + hflag + meminfo.calls))
+ nflag + lflag + Lflag + gflag + hflag + rflag +
+ meminfo.calls))
cmd_usage(pc->curcmd, SYNOPSIS);
}
@@ -9117,7 +9152,7 @@ is_kmem_cache_addr(ulong vaddr, char *kbuf)
* dumps all slab cache names and their addresses.
*/
static void
-kmem_cache_list(void)
+kmem_cache_list(struct meminfo *mi)
{
ulong cache, cache_cache, name;
long next_offset, name_offset;
@@ -9132,7 +9167,7 @@ kmem_cache_list(void)
}
if (vt->flags & (KMALLOC_SLUB|KMALLOC_COMMON)) {
- kmem_cache_list_common();
+ kmem_cache_list_common(mi);
return;
}
@@ -13564,6 +13599,8 @@ dump_vm_table(int verbose)
fprintf(fp, "%sSLAB_OVERLOAD_PAGE", others++ ? "|" : "");\
if (vt->flags & SLAB_CPU_CACHE)
fprintf(fp, "%sSLAB_CPU_CACHE", others++ ? "|" : "");\
+ if (vt->flags & SLAB_ROOT_CACHES)
+ fprintf(fp, "%sSLAB_ROOT_CACHES", others++ ? "|" : "");\
if (vt->flags & USE_VMAP_AREA)
fprintf(fp, "%sUSE_VMAP_AREA", others++ ? "|" : "");\
if (vt->flags & CONFIG_NUMA)
@@ -18044,14 +18081,17 @@ kmem_cache_init_slub(void)
}
static void
-kmem_cache_list_common(void)
+kmem_cache_list_common(struct meminfo *mi)
{
int i, cnt;
ulong *cache_list;
ulong name;
char buf[BUFSIZE];
- cnt = get_kmem_cache_list(&cache_list);
+ if (mi->flags & GET_SLAB_ROOT_CACHES)
+ cnt = get_kmem_cache_root_list(&cache_list);
+ else
+ cnt = get_kmem_cache_list(&cache_list);
for (i = 0; i < cnt; i++) {
fprintf(fp, "%lx ", cache_list[i]);
@@ -18087,7 +18127,11 @@ dump_kmem_cache_slub(struct meminfo *si)
}
order = objects = 0;
- si->cache_count = get_kmem_cache_list(&si->cache_list);
+ if (si->flags & GET_SLAB_ROOT_CACHES)
+ si->cache_count = get_kmem_cache_root_list(&si->cache_list);
+ else
+ si->cache_count = get_kmem_cache_list(&si->cache_list);
+
si->cache_buf = GETBUF(SIZE(kmem_cache));
if (VALID_MEMBER(page_objects) &&
@@ -18168,6 +18212,79 @@ dump_kmem_cache_slub(struct meminfo *si)
!get_kmem_cache_slub_data(GET_SLUB_OBJECTS, si))
si->flags |= SLAB_GATHER_FAILURE;
+ /* accumulate children's slabinfo */
+ if (si->flags & GET_SLAB_ROOT_CACHES) {
+ struct meminfo *mi;
+ int j;
+ char buf2[BUFSIZE];
+
+ mi = (struct meminfo *)GETBUF(sizeof(struct meminfo));
+ memcpy(mi, si, sizeof(struct meminfo));
+
+ mi->cache_count = get_kmem_cache_child_list(&mi->cache_list,
+ si->cache_list[i]);
+
+ if (!mi->cache_count)
+ goto no_children;
+
+ mi->cache_buf = GETBUF(SIZE(kmem_cache));
+
+ for (j = 0; j < mi->cache_count; j++) {
+ BZERO(mi->cache_buf, SIZE(kmem_cache));
+ if (!readmem(mi->cache_list[j], KVADDR, mi->cache_buf,
+ SIZE(kmem_cache), "kmem_cache buffer",
+ RETURN_ON_ERROR|RETURN_PARTIAL))
+ continue;
+
+ name = ULONG(mi->cache_buf + OFFSET(kmem_cache_name));
+ if (!read_string(name, buf2, BUFSIZE-1))
+ sprintf(buf2, "(unknown)");
+
+ objsize = UINT(mi->cache_buf + OFFSET(kmem_cache_objsize));
+ size = UINT(mi->cache_buf + OFFSET(kmem_cache_size));
+ offset = UINT(mi->cache_buf + OFFSET(kmem_cache_offset));
+ if (VALID_MEMBER(kmem_cache_objects)) {
+ objects = UINT(mi->cache_buf +
+ OFFSET(kmem_cache_objects));
+ order = UINT(mi->cache_buf + OFFSET(kmem_cache_order));
+ } else if (VALID_MEMBER(kmem_cache_oo)) {
+ oo = ULONG(mi->cache_buf + OFFSET(kmem_cache_oo));
+ objects = oo_objects(oo);
+ order = oo_order(oo);
+ } else
+ error(FATAL, "cannot determine "
+ "kmem_cache objects/order values\n");
+
+ mi->cache = mi->cache_list[j];
+ mi->curname = buf2;
+ mi->objsize = objsize;
+ mi->size = size;
+ mi->objects = objects;
+ mi->slabsize = (PAGESIZE() << order);
+ mi->inuse = mi->num_slabs = 0;
+ mi->slab_offset = offset;
+ mi->random = VALID_MEMBER(kmem_cache_random) ?
+ ULONG(mi->cache_buf + OFFSET(kmem_cache_random)) : 0;
+
+ if (!get_kmem_cache_slub_data(GET_SLUB_SLABS, mi) ||
+ !get_kmem_cache_slub_data(GET_SLUB_OBJECTS, mi)) {
+ si->flags |= SLAB_GATHER_FAILURE;
+ continue;
+ }
+
+ si->inuse += mi->inuse;
+ si->free += mi->free;
+ si->num_slabs += mi->num_slabs;
+
+ if (CRASHDEBUG(1))
+ dump_kmem_cache_info(mi);
+ }
+ FREEBUF(mi->cache_buf);
+ FREEBUF(mi->cache_list);
+no_children:
+ FREEBUF(mi);
+ }
+
DUMP_KMEM_CACHE_INFO();
if (si->flags & SLAB_GATHER_FAILURE) {
@@ -18964,6 +19081,70 @@ get_kmem_cache_list(ulong **cache_buf)
return cnt;
}
+static int
+get_kmem_cache_root_list(ulong **cache_buf)
+{
+ int cnt;
+ ulong vaddr;
+ struct list_data list_data, *ld;
+
+ get_symbol_data("slab_root_caches", sizeof(void *), &vaddr);
+
+ ld = &list_data;
+ BZERO(ld, sizeof(struct list_data));
+ ld->flags |= LIST_ALLOCATE;
+ ld->start = vaddr;
+ ld->list_head_offset = OFFSET(kmem_cache_memcg_params)
+ + OFFSET(memcg_cache_params___root_caches_node);
+ ld->end = symbol_value("slab_root_caches");
+ if (CRASHDEBUG(3))
+ ld->flags |= VERBOSE;
+
+ cnt = do_list(ld);
+ *cache_buf = ld->list_ptr;
+
+ return cnt;
+}
+
+static int
+get_kmem_cache_child_list(ulong **cache_buf, ulong root)
+{
+ int cnt;
+ ulong vaddr, children;
+ struct list_data list_data, *ld;
+
+ children = root + OFFSET(kmem_cache_memcg_params)
+ + OFFSET(memcg_cache_params_children);
+
+ readmem(children, KVADDR, &vaddr, sizeof(ulong),
+ "kmem_cache.memcg_params.children",
+ FAULT_ON_ERROR);
+
+ /*
+ * When no children, since there is the difference of offset
+ * of children list between root and child, do_list returns
+ * an incorrect cache_buf[0]. So we determine wheather it has
+ * children or not with the value of list_head.next.
+ */
+ if (children == vaddr)
+ return 0;
+
+ ld = &list_data;
+ BZERO(ld, sizeof(struct list_data));
+ ld->flags |= LIST_ALLOCATE;
+ ld->start = vaddr;
+ ld->list_head_offset =
+ OFFSET(kmem_cache_memcg_params)
+ + OFFSET(memcg_cache_params_children_node);
+ ld->end = children;
+ if (CRASHDEBUG(3))
+ ld->flags |= VERBOSE;
+
+ cnt = do_list(ld);
+ *cache_buf = ld->list_ptr;
+
+ return cnt;
+}
/*
* Get the address of the head page of a compound page.
diff --git a/symbols.c b/symbols.c
index bee60ba..2e6713a 100644
--- a/symbols.c
+++ b/symbols.c
@@ -9451,6 +9451,15 @@ dump_offset_table(char *spec, ulong makestruct)
fprintf(fp, " kmem_cache_flags: %ld\n",
OFFSET(kmem_cache_flags));
+ fprintf(fp, " kmem_cache_memcg_params: %ld\n",
+ OFFSET(kmem_cache_memcg_params));
+ fprintf(fp, "memcg_cache_params___root_caches_node: %ld\n",
+ OFFSET(memcg_cache_params___root_caches_node));
+ fprintf(fp, " memcg_cache_params_children: %ld\n",
+ OFFSET(memcg_cache_params_children));
+ fprintf(fp, " memcg_cache_params_children_node: %ld\n",
+ OFFSET(memcg_cache_params_children_node));
+
fprintf(fp, " net_device_next: %ld\n",
OFFSET(net_device_next));
fprintf(fp, " net_device_name: %ld\n",
--
1.8.3.1
-------------- next part --------------
#!/bin/gawk -f
NR > 1 {
if (!sub(/\([0-9]+:.*\)$/, "", $7)) {
# should be root
name[i++] = $7
cache[$7] = $1
objsize[$7] = $2
ssize[$7] = $6
}
alloc[$7] += $3
total[$7] += $4
slabs[$7] += $5
}
END {
printf("%-16s %8s %9s %8s %5s %4s %s\n",
"CACHE", "OBJSIZE", "ALLOCATED", "TOTAL",
"SLABS", "SSIZE", "NAME")
for (j = 0; j < i; j++) {
n = name[j]
printf("%16s %8d %9d %8d %5d %4dk %s\n",
cache[n], objsize[n], alloc[n],
total[n], slabs[n], ssize[n], n)
}
}
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