From: tip-bot for Masami Hiramatsu <mhiramat@redhat.com>
To: linux-tip-commits@vger.kernel.org
Cc: mingo@redhat.com, andersk@ksplice.com, fweisbec@gmail.com,
dle-develop@lists.sourceforge.net, rostedt@goodmis.org,
compudj@krystal.dyndns.org, jbaron@redhat.com,
tglx@linutronix.de, mhiramat@redhat.com,
systemtap@sources.redhat.com,
linux-kernel@vger.kernel.org, hpa@zytor.com,
jkenisto@us.ibm.com, andi@firstfloor.org,
tabbott@ksplice.com, hch@infradead.org,
ananth@in.ibm.com, srikar@linux.vnet.ibm.com,
mingo@elte.hu
Subject: [tip:perf/probes] kprobes: Introduce generic insn_slot framework
Date: Thu, 25 Feb 2010 19:29:00 -0000 [thread overview]
Message-ID: <tip-4610ee1d3638fa05ba8e87ccfa971db8e4033ae7@git.kernel.org> (raw)
In-Reply-To: <20100225133358.6725.82430.stgit@localhost6.localdomain6>
Commit-ID: 4610ee1d3638fa05ba8e87ccfa971db8e4033ae7
Gitweb: http://git.kernel.org/tip/4610ee1d3638fa05ba8e87ccfa971db8e4033ae7
Author: Masami Hiramatsu <mhiramat@redhat.com>
AuthorDate: Thu, 25 Feb 2010 08:33:59 -0500
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Thu, 25 Feb 2010 17:49:24 +0100
kprobes: Introduce generic insn_slot framework
Make insn_slot framework support various size slots.
Current insn_slot just supports one-size instruction buffer
slot. However, kprobes jump optimization needs larger size
buffers.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Anders Kaseorg <andersk@ksplice.com>
Cc: Tim Abbott <tabbott@ksplice.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
LKML-Reference: <20100225133358.6725.82430.stgit@localhost6.localdomain6>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Anders Kaseorg <andersk@ksplice.com>
Cc: Tim Abbott <tabbott@ksplice.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Mathieu Desnoyers <compudj@krystal.dyndns.org>
---
kernel/kprobes.c | 104 +++++++++++++++++++++++++++++++++--------------------
1 files changed, 65 insertions(+), 39 deletions(-)
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ccec774..7810562 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -105,57 +105,74 @@ static struct kprobe_blackpoint kprobe_blacklist[] = {
* stepping on the instruction on a vmalloced/kmalloced/data page
* is a recipe for disaster
*/
-#define INSNS_PER_PAGE (PAGE_SIZE/(MAX_INSN_SIZE * sizeof(kprobe_opcode_t)))
-
struct kprobe_insn_page {
struct list_head list;
kprobe_opcode_t *insns; /* Page of instruction slots */
- char slot_used[INSNS_PER_PAGE];
int nused;
int ngarbage;
+ char slot_used[];
+};
+
+#define KPROBE_INSN_PAGE_SIZE(slots) \
+ (offsetof(struct kprobe_insn_page, slot_used) + \
+ (sizeof(char) * (slots)))
+
+struct kprobe_insn_cache {
+ struct list_head pages; /* list of kprobe_insn_page */
+ size_t insn_size; /* size of instruction slot */
+ int nr_garbage;
};
+static int slots_per_page(struct kprobe_insn_cache *c)
+{
+ return PAGE_SIZE/(c->insn_size * sizeof(kprobe_opcode_t));
+}
+
enum kprobe_slot_state {
SLOT_CLEAN = 0,
SLOT_DIRTY = 1,
SLOT_USED = 2,
};
-static DEFINE_MUTEX(kprobe_insn_mutex); /* Protects kprobe_insn_pages */
-static LIST_HEAD(kprobe_insn_pages);
-static int kprobe_garbage_slots;
-static int collect_garbage_slots(void);
+static DEFINE_MUTEX(kprobe_insn_mutex); /* Protects kprobe_insn_slots */
+static struct kprobe_insn_cache kprobe_insn_slots = {
+ .pages = LIST_HEAD_INIT(kprobe_insn_slots.pages),
+ .insn_size = MAX_INSN_SIZE,
+ .nr_garbage = 0,
+};
+static int __kprobes collect_garbage_slots(struct kprobe_insn_cache *c);
/**
* __get_insn_slot() - Find a slot on an executable page for an instruction.
* We allocate an executable page if there's no room on existing ones.
*/
-static kprobe_opcode_t __kprobes *__get_insn_slot(void)
+static kprobe_opcode_t __kprobes *__get_insn_slot(struct kprobe_insn_cache *c)
{
struct kprobe_insn_page *kip;
retry:
- list_for_each_entry(kip, &kprobe_insn_pages, list) {
- if (kip->nused < INSNS_PER_PAGE) {
+ list_for_each_entry(kip, &c->pages, list) {
+ if (kip->nused < slots_per_page(c)) {
int i;
- for (i = 0; i < INSNS_PER_PAGE; i++) {
+ for (i = 0; i < slots_per_page(c); i++) {
if (kip->slot_used[i] == SLOT_CLEAN) {
kip->slot_used[i] = SLOT_USED;
kip->nused++;
- return kip->insns + (i * MAX_INSN_SIZE);
+ return kip->insns + (i * c->insn_size);
}
}
- /* Surprise! No unused slots. Fix kip->nused. */
- kip->nused = INSNS_PER_PAGE;
+ /* kip->nused is broken. Fix it. */
+ kip->nused = slots_per_page(c);
+ WARN_ON(1);
}
}
/* If there are any garbage slots, collect it and try again. */
- if (kprobe_garbage_slots && collect_garbage_slots() == 0) {
+ if (c->nr_garbage && collect_garbage_slots(c) == 0)
goto retry;
- }
- /* All out of space. Need to allocate a new page. Use slot 0. */
- kip = kmalloc(sizeof(struct kprobe_insn_page), GFP_KERNEL);
+
+ /* All out of space. Need to allocate a new page. */
+ kip = kmalloc(KPROBE_INSN_PAGE_SIZE(slots_per_page(c)), GFP_KERNEL);
if (!kip)
return NULL;
@@ -170,20 +187,23 @@ static kprobe_opcode_t __kprobes *__get_insn_slot(void)
return NULL;
}
INIT_LIST_HEAD(&kip->list);
- list_add(&kip->list, &kprobe_insn_pages);
- memset(kip->slot_used, SLOT_CLEAN, INSNS_PER_PAGE);
+ memset(kip->slot_used, SLOT_CLEAN, slots_per_page(c));
kip->slot_used[0] = SLOT_USED;
kip->nused = 1;
kip->ngarbage = 0;
+ list_add(&kip->list, &c->pages);
return kip->insns;
}
+
kprobe_opcode_t __kprobes *get_insn_slot(void)
{
- kprobe_opcode_t *ret;
+ kprobe_opcode_t *ret = NULL;
+
mutex_lock(&kprobe_insn_mutex);
- ret = __get_insn_slot();
+ ret = __get_insn_slot(&kprobe_insn_slots);
mutex_unlock(&kprobe_insn_mutex);
+
return ret;
}
@@ -199,7 +219,7 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx)
* so as not to have to set it up again the
* next time somebody inserts a probe.
*/
- if (!list_is_singular(&kprobe_insn_pages)) {
+ if (!list_is_singular(&kip->list)) {
list_del(&kip->list);
module_free(NULL, kip->insns);
kfree(kip);
@@ -209,49 +229,55 @@ static int __kprobes collect_one_slot(struct kprobe_insn_page *kip, int idx)
return 0;
}
-static int __kprobes collect_garbage_slots(void)
+static int __kprobes collect_garbage_slots(struct kprobe_insn_cache *c)
{
struct kprobe_insn_page *kip, *next;
/* Ensure no-one is interrupted on the garbages */
synchronize_sched();
- list_for_each_entry_safe(kip, next, &kprobe_insn_pages, list) {
+ list_for_each_entry_safe(kip, next, &c->pages, list) {
int i;
if (kip->ngarbage == 0)
continue;
kip->ngarbage = 0; /* we will collect all garbages */
- for (i = 0; i < INSNS_PER_PAGE; i++) {
+ for (i = 0; i < slots_per_page(c); i++) {
if (kip->slot_used[i] == SLOT_DIRTY &&
collect_one_slot(kip, i))
break;
}
}
- kprobe_garbage_slots = 0;
+ c->nr_garbage = 0;
return 0;
}
-void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty)
+static void __kprobes __free_insn_slot(struct kprobe_insn_cache *c,
+ kprobe_opcode_t *slot, int dirty)
{
struct kprobe_insn_page *kip;
- mutex_lock(&kprobe_insn_mutex);
- list_for_each_entry(kip, &kprobe_insn_pages, list) {
- if (kip->insns <= slot &&
- slot < kip->insns + (INSNS_PER_PAGE * MAX_INSN_SIZE)) {
- int i = (slot - kip->insns) / MAX_INSN_SIZE;
+ list_for_each_entry(kip, &c->pages, list) {
+ long idx = ((long)slot - (long)kip->insns) / c->insn_size;
+ if (idx >= 0 && idx < slots_per_page(c)) {
+ WARN_ON(kip->slot_used[idx] != SLOT_USED);
if (dirty) {
- kip->slot_used[i] = SLOT_DIRTY;
+ kip->slot_used[idx] = SLOT_DIRTY;
kip->ngarbage++;
+ if (++c->nr_garbage > slots_per_page(c))
+ collect_garbage_slots(c);
} else
- collect_one_slot(kip, i);
- break;
+ collect_one_slot(kip, idx);
+ return;
}
}
+ /* Could not free this slot. */
+ WARN_ON(1);
+}
- if (dirty && ++kprobe_garbage_slots > INSNS_PER_PAGE)
- collect_garbage_slots();
-
+void __kprobes free_insn_slot(kprobe_opcode_t * slot, int dirty)
+{
+ mutex_lock(&kprobe_insn_mutex);
+ __free_insn_slot(&kprobe_insn_slots, slot, dirty);
mutex_unlock(&kprobe_insn_mutex);
}
#endif
next prev parent reply other threads:[~2010-02-25 19:29 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-02-25 13:29 [PATCH -tip v3&10 00/18] perf-probe updates - optprobe, elfutils and lazy matching Masami Hiramatsu
2010-02-25 13:29 ` [PATCH -tip v3&10 06/18] kprobes/x86: Cleanup save/restore registers Masami Hiramatsu
2010-02-25 19:30 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:29 ` [PATCH -tip v3&10 04/18] kprobes: Jump optimization sysctl interface Masami Hiramatsu
2010-02-25 19:29 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:29 ` [PATCH -tip v3&10 02/18] kprobes: Introduce generic insn_slot framework Masami Hiramatsu
2010-02-25 15:21 ` Mathieu Desnoyers
2010-03-02 2:55 ` Masami Hiramatsu
2010-03-03 0:19 ` Masami Hiramatsu
2010-03-03 0:37 ` Mathieu Desnoyers
2010-03-03 0:36 ` Masami Hiramatsu
2010-02-25 19:29 ` tip-bot for Masami Hiramatsu [this message]
2010-02-25 13:29 ` [PATCH -tip v3&10 05/18] kprobes/x86: Boost probes when reentering Masami Hiramatsu
2010-02-25 19:30 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:29 ` [PATCH -tip v3&10 03/18] kprobes: Introduce kprobes jump optimization Masami Hiramatsu
2010-02-25 19:30 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:29 ` [PATCH -tip v3&10 01/18] kprobes/x86: Cleanup RELATIVEJUMP_INSTRUCTION to RELATIVEJUMP_OPCODE Masami Hiramatsu
2010-02-25 15:16 ` Mathieu Desnoyers
2010-02-25 19:29 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 10/18] perf probe: Do not show --line option without dwarf support Masami Hiramatsu
2010-02-25 19:31 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 12/18] perf probe: Fix bugs in line range finder Masami Hiramatsu
2010-02-25 19:32 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 11/18] perf probe: Update perf probe document Masami Hiramatsu
2010-02-25 19:31 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 08/18] kprobes/x86: Support kprobes jump optimization on x86 Masami Hiramatsu
2010-02-25 19:31 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 07/18] x86: Add text_poke_smp for SMP cross modifying code Masami Hiramatsu
2010-02-25 15:38 ` Mathieu Desnoyers
2010-02-26 3:50 ` Masami Hiramatsu
2010-03-03 0:48 ` Mathieu Desnoyers
2010-03-03 0:57 ` Masami Hiramatsu
2010-02-25 19:31 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:30 ` [PATCH -tip v3&10 09/18] kprobes: Add documents of jump optimization Masami Hiramatsu
2010-02-25 19:31 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:31 ` [PATCH -tip v3&10 18/18] perf probe: Add lazy line matching support Masami Hiramatsu
2010-02-25 19:33 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:31 ` [PATCH -tip v3&10 15/18] perf probe: Use libdw callback routines Masami Hiramatsu
2010-02-25 19:33 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:31 ` [PATCH -tip v3&10 13/18] perf probe: Rename probe finder functions Masami Hiramatsu
2010-02-25 19:32 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 13:31 ` [PATCH -tip v3&10 17/18] perf probe: show more lines after last line Masami Hiramatsu
2010-02-25 19:33 ` [tip:perf/probes] perf probe: Show " tip-bot for Masami Hiramatsu
2010-02-25 13:31 ` [PATCH -tip v3&10 14/18] perf probe: Use elfutils-libdw for analyzing debuginfo Masami Hiramatsu
2010-02-25 19:32 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
2010-02-25 14:12 ` [PATCH -tip v3&10 16/18] perf probe: Check function address range strictly in line finder Masami Hiramatsu
2010-02-25 19:33 ` [tip:perf/probes] " tip-bot for Masami Hiramatsu
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=tip-4610ee1d3638fa05ba8e87ccfa971db8e4033ae7@git.kernel.org \
--to=mhiramat@redhat.com \
--cc=ananth@in.ibm.com \
--cc=andersk@ksplice.com \
--cc=andi@firstfloor.org \
--cc=compudj@krystal.dyndns.org \
--cc=dle-develop@lists.sourceforge.net \
--cc=fweisbec@gmail.com \
--cc=hch@infradead.org \
--cc=hpa@zytor.com \
--cc=jbaron@redhat.com \
--cc=jkenisto@us.ibm.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-tip-commits@vger.kernel.org \
--cc=mingo@elte.hu \
--cc=mingo@redhat.com \
--cc=rostedt@goodmis.org \
--cc=srikar@linux.vnet.ibm.com \
--cc=systemtap@sources.redhat.com \
--cc=tabbott@ksplice.com \
--cc=tglx@linutronix.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).