Hello Dave,
Please check the patch.
--
Regards
Qiao Nuohan
From 3d313aaf5d9fedd91e81ac596fe407614dd57de1 Mon Sep 17 00:00:00 2001
From: Qiao Nuohan <qiaonuohan@xxxxxxxxxxxxxx>
Date: Wed, 11 Jun 2014 10:01:21 +0800
Subject: [PATCH] Fix ksm.c
Because of the following kernel patch, 'root_stable_tree' and
'struct stable_node' are changed.
<cut>
ef53d16cded7f89b3843b7a96970dab897843ea5
90bd6fd31c8097ee4ddcb74b7e08363134863de5
4146d2d673e8d6abf9b30a5b5dd8cd95f29632eb
<cut>
Another two change are listed below.
1. add mm_struct's address for the task.
ksm displayed ksm page's messages like below
<cut>
PAGE: ffffea000451f180
STABLE_NODE: ffff88004866b6c0
PHYSICAL ADDRESS: 1147c6000
PID: 1318 MAPPINGS: 7707
PID: 1297 MAPPINGS: 4965
<cut>
Now, MM item is added to show the mm_struct's address related to task, like
below
<cut>
PAGE: ffffea000451f180
STABLE_NODE: ffff88004866b6c0
PHYSICAL ADDRESS: 1147c6000
PID: 1318 MAPPINGS: 7707 MM: ffff88007f8abe80
PID: 1297 MAPPINGS: 4965 MM: ffff88007f8aa580
<cut>
2. the task that uses ksm pages may have exited. this patch will change to
show the exited task's "MAPPINGS" and "MM" like below
<cut>
PAGE: ffffea000292ca40
STABLE_NODE: ffff88009fe8e9c0
PHYSICAL ADDRESS: a4b29000
PID: - MAPPINGS: 1 MM: ffff880115f28000
PID: - MAPPINGS: 1 MM: ffff8800cdd7a580
<cut>
task has exited, so PID is "-"
Signed-off-by: Qiao Nuohan <qiaonuohan@xxxxxxxxxxxxxx>
---
extensions/ksm.c | 289 ++++++++++++++++++++++++++++++++++++-------------------
1 file changed, 192 insertions(+), 97 deletions(-)
diff --git a/extensions/ksm.c b/extensions/ksm.c
index ce02318..ef97c92 100644
--- a/extensions/ksm.c
+++ b/extensions/ksm.c
@@ -1,6 +1,7 @@
/*
- * Copyright (C) 2013 FUJITSU LIMITED
+ * Copyright (C) 2013-2014 FUJITSU LIMITED
* Author: Zhang Yanfei <zhangyanfei@xxxxxxxxxxxxxx>
+ * Signed-off-by: Qiao Nuohan <qiaonuohan@xxxxxxxxxxxxxx>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -22,7 +23,7 @@ void cmd_ksm(void);
char *help_ksm[];
static struct command_table_entry command_table[] = {
- { "ksm", cmd_ksm, help_ksm, 0},
+ { "ksm", cmd_ksm, help_ksm, 0},
{ NULL },
};
@@ -35,7 +36,8 @@ struct ksm_offset_table {
long rmap_item_hlist;
} ksm_offset_table;
-#define KSM_ASSIGN_OFFSET(X) (ksm_offset_table.X)
+#define KSM_ASSIGN_OFFSET(X) (ksm_offset_table.X)
+#define KSM_INVALID_MEMBER(X) (ksm_offset_table.X == INVALID_OFFSET)
#define KSM_MEMBER_OFFSET_INIT(X, Y, Z) (KSM_ASSIGN_OFFSET(X) = MEMBER_OFFSET(Y, Z))
#define KSM_ANON_MEMBER_OFFSET_INIT(X, Y, Z) (KSM_ASSIGN_OFFSET(X) = ANON_MEMBER_OFFSET(Y, Z))
#define KSM_OFFSET(X) (OFFSET_verify(ksm_offset_table.X, (char *)__FUNCTION__, __FILE__, __LINE__, #X))
@@ -50,27 +52,30 @@ struct page_ref {
ulong mm;
ulong pid;
int ref;
+ struct page_ref *next;
};
static void dump_ksm(struct meminfo *);
void __attribute__((constructor))
ksm_init(void) /* Register the command set. */
-{
+{
if (STRUCT_EXISTS("stable_node")) {
KSM_MEMBER_OFFSET_INIT(stable_node_node, "stable_node", "node");
+ if (KSM_INVALID_MEMBER(stable_node_node))
+ KSM_ANON_MEMBER_OFFSET_INIT(stable_node_node, "stable_node", "node");
+
KSM_MEMBER_OFFSET_INIT(stable_node_hlist, "stable_node", "hlist");
KSM_MEMBER_OFFSET_INIT(stable_node_kpfn, "stable_node", "kpfn");
- KSM_MEMBER_OFFSET_INIT(stable_node_node, "stable_node", "node");
KSM_MEMBER_OFFSET_INIT(rmap_item_mm, "rmap_item", "mm");
KSM_MEMBER_OFFSET_INIT(rmap_item_address, "rmap_item", "address");
KSM_ANON_MEMBER_OFFSET_INIT(rmap_item_hlist, "rmap_item", "hlist");
} else
- error(FATAL, "ksm_init: stable_node does not exist\n");
+ error(FATAL, "ksm_init: stable_node does not exist\n");
register_extension(command_table);
}
-
+
void __attribute__((destructor))
ksm_fini(void) { }
@@ -139,15 +144,17 @@ cmd_ksm(void)
}
char *help_ksm[] = {
- "ksm",
+ "ksm",
"kernel samepage merging (KSM) information",
- "[-v] [[-p] address ...]",
-
+ "[-v] [[-p] address ...]",
+
" This command displays information about all KSM pages currently",
" in use. For each KSM page, the display includes its stable_node",
- " address, its page struct address, its physical address, the TGID/PID",
- " for each task that is using the page, and the number of mappings in",
- " the task's address space for the page.",
+ " address, its page struct address, its physical address, the TGID/PID",
+ " for each task that is using the page, the number of mappings in the",
+ " task's address space for the page, and the mm_struct address of the",
+ " task. If pid is '-', the task has exited and the ksm page has not",
+ " been removed.",
" ",
" -v also dump each virtual address in a PID's virtual address",
" space that maps the KSM page.",
@@ -159,88 +166,129 @@ char *help_ksm[] = {
"\nEXAMPLE",
" Display information about all KSM pages:\n",
" %s> ksm",
-// " STABLE_NODE : ffff8806248c2d80",
-// " PAGE : ffffea000ae7f6a8",
-// " PHYSICAL ADDRESS: 31db43000",
- " PAGE: ffffea000ae7f6a8",
- " STABLE_NODE: ffff8806248c2d80",
- " PHYSICAL ADDRESS: 31db43000",
- " PID: 2205 MAPPINGS: 2",
+ " PAGE: ffffea000451f180",
+ " STABLE_NODE: ffff88004866b6c0",
+ " PHYSICAL ADDRESS: 1147c6000",
+ " PID: 1318 MAPPINGS: 7707 MM: ffff88007f8abe80",
+ " PID: 1297 MAPPINGS: 4965 MM: ffff88007f8aa580",
"",
-// " STABLE_NODE : ffff880624aa57b8",
-// " PAGE : ffffea000ae800f0",
-// " PHYSICAL ADDRESS: 31db72000",
- " PAGE: ffffea000ae800f0",
- " STABLE_NODE: ffff880624aa57b8",
- " PHYSICAL ADDRESS: 31db72000",
- " PID: 2205 MAPPINGS: 2",
+ " PAGE: ffffea0003413c40",
+ " STABLE_NODE: ffff880117bfbfc0",
+ " PHYSICAL ADDRESS: d04f1000",
+ " PID: 1297 MAPPINGS: 1 MM: ffff88007f8aa580",
+ " PID: 1318 MAPPINGS: 1 MM: ffff88007f8abe80",
"",
-// " STABLE_NODE : ffff8806248c2dd0",
-// " PAGE : ffffea000ae7f8d8",
-// " PHYSICAL ADDRESS: 31db4d000",
- " PAGE: ffffea000ae7f8d8",
- " STABLE_NODE: ffff8806248c2dd0",
- " PHYSICAL ADDRESS: 31db4d000",
- " PID: 2205 MAPPINGS: 2",
+ " PAGE: ffffea00021e9880",
+ " STABLE_NODE: ffff880054ee1f30",
+ " PHYSICAL ADDRESS: 87a62000",
+ " PID: 1297 MAPPINGS: 2 MM: ffff88007f8aa580",
" ...",
"",
" Display all information about the KSM page whose physical",
- " address is 0x626e60000:\n",
- " %s> ksm -v 626e60000",
- " PAGE: ffffea0015882500",
- " STABLE_NODE: ffff88028b2af3d0",
- " PHYSICAL ADDRESS: 626e60000",
- " PID: 2603 MAPPINGS: 8",
+ " address is 0xffffea000168cd00:\n",
+ " %s> ksm -v ffffea000168cd00",
+ " PAGE: ffffea000168cd00",
+ " STABLE_NODE: ffff88007153ce10",
+ " PHYSICAL ADDRESS: 5a334000",
+ " PID: 1297 MAPPINGS: 4 MM: ffff88007f8aa580",
" VIRTUAL:",
- " 7ff46bcb4000",
- " 7ff46bcad000",
- " 7ff46bc9f000",
- " 7ff46bc7c000",
- " 7ff46bc6e000",
- " 7ff46bc67000",
- " 7ff46bc60000",
- " 7ff46bc59000",
+ " 7f8cb91f9000",
+ " 7f8cb8f28000",
+ " 7f8cb7abf000",
+ " 7f8cb79c7000",
+ "",
+ " PID: 1318 MAPPINGS: 4 MM: ffff88007f8abe80",
+ " VIRTUAL:",
+ " 7f7ca0703000",
+ " 7f7c9f15e000",
+ " 7f7c9ef8f000",
+ " 7f7c9e96b000",
NULL
};
+/*
+ * find the page_ref whose mm is same as mm
+ */
+static struct page_ref *
+find_match_ref(struct page_ref *ref_list, ulong mm)
+{
+ struct page_ref *next_ref = ref_list;
+
+ while (next_ref) {
+ if (next_ref->mm == mm) {
+ break;
+ } else {
+ next_ref = next_ref->next;
+ }
+ }
+
+ return next_ref;
+}
/*
- * dump_ksm() displays information of ksm pages.
+ * get the pid of the task that mm_struct belongs to, if not find,
+ * return (ulong)-1
*/
+static ulong
+find_pid(ulong mm)
+{
+ struct task_context *tc;
+ int i;
+ ulong pid = -1;
+
+ tc = FIRST_CONTEXT();
+ for (i = 0; i < RUNNING_TASKS(); i++, tc++) {
+ if (tc->mm_struct == mm) {
+ pid = tc->pid;
+ break;
+ }
+ }
+
+ return pid;
+}
+
static void
-dump_ksm(struct meminfo *mi)
+add_to_ref_list(struct page_ref **ref_list_ptr, struct page_ref *ref)
{
- ulong root_stable_tree, stable_node, kpfn;
+ ref->next = *ref_list_ptr;
+ *ref_list_ptr = ref;
+}
+
+static void
+clean_ref_list(struct page_ref *ref_list)
+{
+ struct page_ref *tmp_ref, *next_ref;
+
+ tmp_ref = ref_list;
+
+ while (tmp_ref) {
+ next_ref = tmp_ref->next;
+ FREEBUF(tmp_ref);
+ tmp_ref = next_ref;
+ }
+}
+
+/*
+ * dump the ksm pages from the stable tree
+ */
+static void
+dump_stable_tree(struct meminfo *mi, struct rb_root *root)
+{
+ ulong stable_node, kpfn;
ulong rmap_item, mm, paddr;
- struct rb_root *root;
struct rb_node *node;
ulong first, next;
- struct task_context *tc;
- int i, ref_size, refs, found;
- struct page_ref *ref;
+ int found;
+ struct page_ref *ref_list;
ulong page, address;
- if (!symbol_exists("root_stable_tree")) {
- error(INFO, "cannot determine ksm stable tree address from root_stable_tree\n");
- return;
- }
- root_stable_tree = symbol_value("root_stable_tree");
- root = (struct rb_root *)root_stable_tree;
-
- refs = 0;
- ref_size = sizeof(struct page_ref) * RUNNING_TASKS();
- ref = (struct page_ref *)GETBUF(ref_size);
- BZERO(ref, ref_size);
-
found = (mi && mi->flags & ADDRESS_SPECIFIED) ? 0 : -1;
+
for (node = rb_first(root); node; node = rb_next(node)) {
stable_node = (ulong) node - KSM_OFFSET(stable_node_node);
if (CRASHDEBUG(1))
fprintf(fp, " stable_node = %lx\n", stable_node);
- readmem(stable_node + KSM_OFFSET(stable_node_hlist),
- KVADDR, &first, sizeof(ulong),
- "stable_node hlist", FAULT_ON_ERROR);
readmem(stable_node + KSM_OFFSET(stable_node_kpfn),
KVADDR, &kpfn, sizeof(ulong),
"stable_node kpfn", FAULT_ON_ERROR);
@@ -259,10 +307,6 @@ dump_ksm(struct meminfo *mi)
if (found == 0)
continue;
-// fprintf(fp, "STABLE_NODE : %lx\n", stable_node);
-// fprintf(fp, "PAGE : %lx\n", page);
-// fprintf(fp, "PHYSICAL ADDRESS: %lx\n\n", paddr);
-
fprintf(fp, " PAGE: %lx\n", page);
fprintf(fp, " STABLE_NODE: %lx\n", stable_node);
fprintf(fp, "PHYSICAL ADDRESS: %lx\n", paddr);
@@ -272,41 +316,51 @@ dump_ksm(struct meminfo *mi)
"stable_node hlist", FAULT_ON_ERROR);
next = first;
+ ref_list = NULL;
+ struct page_ref *tmp_ref = NULL;
+
while (next) {
rmap_item = next - KSM_OFFSET(rmap_item_hlist);
readmem(rmap_item + KSM_OFFSET(rmap_item_mm),
KVADDR, &mm, sizeof(ulong),
"rmap_item mm", FAULT_ON_ERROR);
- for (i = 0; i < refs; i++) {
- if (ref[i].mm == mm) {
- ref[i].ref += 1;
- goto next;
- }
- }
-
- tc = FIRST_CONTEXT();
- for (i = 0; i < RUNNING_TASKS(); i++, tc++) {
- if (tc->mm_struct == mm) {
- ref[refs].mm = mm;
- ref[refs].pid = tc->pid;
- ref[refs++].ref = 1;
- break;
- }
+ //get the page_ref whose mm is equal to rmap_item's mm
+ tmp_ref = find_match_ref(ref_list, mm);
+ if (tmp_ref) {
+ tmp_ref->ref += 1;
+ } else {
+ //create a new page_ref
+ tmp_ref = (struct page_ref *)GETBUF(
+ sizeof(struct page_ref));
+ tmp_ref->mm = mm;
+ tmp_ref->pid = find_pid(mm);
+ tmp_ref->ref = 1;
+
+ add_to_ref_list(&ref_list, tmp_ref);
}
-next:
readmem(next + OFFSET(hlist_node_next),
KVADDR, &next, sizeof(ulong),
"hlist_node next", FAULT_ON_ERROR);
};
- for (i = 0; i < refs; i++) {
- fprintf(fp, " PID: %ld ", ref[i].pid);
- fprintf(fp, " MAPPINGS: %d\n", ref[i].ref);
+ tmp_ref = ref_list;
+ while (tmp_ref) {
+ if (tmp_ref->pid == (ulong)-1) {
+ /*
+ * the task has exited, but the ksm pages has
+ * not been cleared yet.
+ */
+ fprintf(fp, " PID: - ");
+ } else {
+ fprintf(fp, " PID: %ld ", tmp_ref->pid);
+ }
+ fprintf(fp, " MAPPINGS: %d ", tmp_ref->ref);
+ fprintf(fp, " MM: %lx\n", tmp_ref->mm);
if (!(mi && mi->flags & VERBOSE))
- continue;
+ goto next_ref;
fprintf(fp, " VIRTUAL:\n");
next = first;
@@ -315,7 +369,7 @@ next:
readmem(rmap_item + KSM_OFFSET(rmap_item_mm),
KVADDR, &mm, sizeof(ulong),
"rmap_item mm", FAULT_ON_ERROR);
- if (ref[i].mm == mm) {
+ if (tmp_ref->mm == mm) {
readmem(rmap_item + KSM_OFFSET(rmap_item_address),
KVADDR, &address, sizeof(ulong),
"rmap_item address", FAULT_ON_ERROR);
@@ -327,10 +381,16 @@ next:
"hlist_node next", FAULT_ON_ERROR);
}
fprintf(fp, "\n");
+
+next_ref:
+ tmp_ref = tmp_ref->next;
}
+
+ //clear all page_ref
+ clean_ref_list(ref_list);
+
if (!(mi && mi->flags & VERBOSE))
fprintf(fp, "\n");
- refs = 0;
if (found == 1)
break;
@@ -339,6 +399,41 @@ next:
if (found == 0)
fprintf(fp, "address 0x%llx cannot specify a ksm stable tree node\n",
mi->spec_addr);
+}
- FREEBUF(ref);
+/*
+ * dump_ksm() displays information of ksm pages.
+ */
+static void
+dump_ksm(struct meminfo *mi)
+{
+ ulong root_stable_tree_ptr;
+ ulong ksm_nr_node_ids_ptr;
+ int ksm_nr_node_ids;
+ struct rb_root *root;
+ int i;
+
+ if (!symbol_exists("root_stable_tree")) {
+ error(INFO, "cannot determine ksm stable tree address from root_stable_tree\n");
+ return;
+ }
+ root_stable_tree_ptr = symbol_value("root_stable_tree");
+
+ if (symbol_exists("ksm_nr_node_ids")) {
+ //root_stable_tree_ptr is an array of stable tree root
+ ksm_nr_node_ids_ptr = symbol_value("ksm_nr_node_ids");
+ readmem(ksm_nr_node_ids_ptr, KVADDR, &ksm_nr_node_ids,
+ sizeof(ksm_nr_node_ids), "ksm_nr_node_ids",
+ FAULT_ON_ERROR);
+
+ readmem(root_stable_tree_ptr, KVADDR, &root, sizeof(ulong),
+ "first stable tree root", FAULT_ON_ERROR);
+
+ for (i = 0; i < ksm_nr_node_ids; i++) {
+ dump_stable_tree(mi, root + i);
+ }
+ } else {
+ root = (struct rb_root *)root_stable_tree_ptr;
+ dump_stable_tree(mi, root);
+ }
}
--
1.8.5.3
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