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-rw-r--r--Documentation/kernel-parameters.txt10
-rw-r--r--MAINTAINERS6
-rw-r--r--include/linux/kmemtrace.h85
-rw-r--r--init/main.c2
-rw-r--r--lib/Kconfig.debug28
-rw-r--r--mm/Makefile1
-rw-r--r--mm/kmemtrace.c335
7 files changed, 467 insertions, 0 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index e0f346d..542c2d88 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -49,6 +49,7 @@ parameter is applicable:
ISAPNP ISA PnP code is enabled.
ISDN Appropriate ISDN support is enabled.
JOY Appropriate joystick support is enabled.
+ KMEMTRACE kmemtrace is enabled.
LIBATA Libata driver is enabled
LP Printer support is enabled.
LOOP Loopback device support is enabled.
@@ -1018,6 +1019,15 @@ and is between 256 and 4096 characters. It is defined in the file
use the HighMem zone if it exists, and the Normal
zone if it does not.
+ kmemtrace.enable= [KNL,KMEMTRACE] Format: { yes | no }
+ Controls whether kmemtrace is enabled
+ at boot-time.
+
+ kmemtrace.subbufs=n [KNL,KMEMTRACE] Overrides the number of
+ subbufs kmemtrace's relay channel has. Set this
+ higher than default (KMEMTRACE_N_SUBBUFS in code) if
+ you experience buffer overruns.
+
movablecore=nn[KMG] [KNL,X86-32,IA-64,PPC,X86-64] This parameter
is similar to kernelcore except it specifies the
amount of memory used for migratable allocations.
diff --git a/MAINTAINERS b/MAINTAINERS
index 618c1ef..e2b3c85 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2565,6 +2565,12 @@ M: jason.wessel@windriver.com
L: kgdb-bugreport@lists.sourceforge.net
S: Maintained
+KMEMTRACE
+P: Eduard - Gabriel Munteanu
+M: eduard.munteanu@linux360.ro
+L: linux-kernel@vger.kernel.org
+S: Maintained
+
KPROBES
P: Ananth N Mavinakayanahalli
M: ananth@in.ibm.com
diff --git a/include/linux/kmemtrace.h b/include/linux/kmemtrace.h
new file mode 100644
index 0000000..2c33201
--- /dev/null
+++ b/include/linux/kmemtrace.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2008 Eduard - Gabriel Munteanu
+ *
+ * This file is released under GPL version 2.
+ */
+
+#ifndef _LINUX_KMEMTRACE_H
+#define _LINUX_KMEMTRACE_H
+
+#ifdef __KERNEL__
+
+#include <linux/types.h>
+#include <linux/marker.h>
+
+enum kmemtrace_type_id {
+ KMEMTRACE_TYPE_KMALLOC = 0, /* kmalloc() or kfree(). */
+ KMEMTRACE_TYPE_CACHE, /* kmem_cache_*(). */
+ KMEMTRACE_TYPE_PAGES, /* __get_free_pages() and friends. */
+};
+
+#ifdef CONFIG_KMEMTRACE
+
+extern void kmemtrace_init(void);
+
+static inline void kmemtrace_mark_alloc_node(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr,
+ size_t bytes_req,
+ size_t bytes_alloc,
+ gfp_t gfp_flags,
+ int node)
+{
+ trace_mark(kmemtrace_alloc, "type_id %d call_site %lu ptr %lu "
+ "bytes_req %lu bytes_alloc %lu gfp_flags %lu node %d",
+ type_id, call_site, (unsigned long) ptr,
+ bytes_req, bytes_alloc, (unsigned long) gfp_flags, node);
+}
+
+static inline void kmemtrace_mark_free(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr)
+{
+ trace_mark(kmemtrace_free, "type_id %d call_site %lu ptr %lu",
+ type_id, call_site, (unsigned long) ptr);
+}
+
+#else /* CONFIG_KMEMTRACE */
+
+static inline void kmemtrace_init(void)
+{
+}
+
+static inline void kmemtrace_mark_alloc_node(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr,
+ size_t bytes_req,
+ size_t bytes_alloc,
+ gfp_t gfp_flags,
+ int node)
+{
+}
+
+static inline void kmemtrace_mark_free(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr)
+{
+}
+
+#endif /* CONFIG_KMEMTRACE */
+
+static inline void kmemtrace_mark_alloc(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr,
+ size_t bytes_req,
+ size_t bytes_alloc,
+ gfp_t gfp_flags)
+{
+ kmemtrace_mark_alloc_node(type_id, call_site, ptr,
+ bytes_req, bytes_alloc, gfp_flags, -1);
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* _LINUX_KMEMTRACE_H */
+
diff --git a/init/main.c b/init/main.c
index 7e117a2..be1fe224 100644
--- a/init/main.c
+++ b/init/main.c
@@ -69,6 +69,7 @@
#include <asm/setup.h>
#include <asm/sections.h>
#include <asm/cacheflush.h>
+#include <linux/kmemtrace.h>
#ifdef CONFIG_X86_LOCAL_APIC
#include <asm/smp.h>
@@ -653,6 +654,7 @@ asmlinkage void __init start_kernel(void)
enable_debug_pagealloc();
cpu_hotplug_init();
kmem_cache_init();
+ kmemtrace_init();
debug_objects_mem_init();
idr_init_cache();
setup_per_cpu_pageset();
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index b0f239e..78d669b 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -803,6 +803,34 @@ config FIREWIRE_OHCI_REMOTE_DMA
If unsure, say N.
+config KMEMTRACE
+ bool "Kernel memory tracer (kmemtrace)"
+ depends on RELAY && DEBUG_FS && MARKERS
+ help
+ kmemtrace provides tracing for slab allocator functions, such as
+ kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected
+ data is then fed to the userspace application in order to analyse
+ allocation hotspots, internal fragmentation and so on, making it
+ possible to see how well an allocator performs, as well as debug
+ and profile kernel code.
+
+ This requires an userspace application to use. See
+ Documentation/vm/kmemtrace.txt for more information.
+
+ Saying Y will make the kernel somewhat larger and slower. However,
+ if you disable kmemtrace at run-time or boot-time, the performance
+ impact is minimal (depending on the arch the kernel is built for).
+
+ If unsure, say N.
+
+config KMEMTRACE_DEFAULT_ENABLED
+ bool "Enabled by default at boot"
+ depends on KMEMTRACE
+ help
+ Say Y here to enable kmemtrace at boot-time by default. Whatever
+ the choice, the behavior can be overridden by a kernel parameter,
+ as described in documentation.
+
menuconfig BUILD_DOCSRC
bool "Build targets in Documentation/ tree"
depends on HEADERS_CHECK
diff --git a/mm/Makefile b/mm/Makefile
index c06b45a..3782eb6 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -34,3 +34,4 @@ obj-$(CONFIG_MIGRATION) += migrate.o
obj-$(CONFIG_SMP) += allocpercpu.o
obj-$(CONFIG_QUICKLIST) += quicklist.o
obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o
+obj-$(CONFIG_KMEMTRACE) += kmemtrace.o
diff --git a/mm/kmemtrace.c b/mm/kmemtrace.c
new file mode 100644
index 0000000..83ad1cc
--- /dev/null
+++ b/mm/kmemtrace.c
@@ -0,0 +1,335 @@
+/*
+ * Copyright (C) 2008 Pekka Enberg, Eduard - Gabriel Munteanu
+ *
+ * This file is released under GPL version 2.
+ */
+
+#include <linux/string.h>
+#include <linux/debugfs.h>
+#include <linux/relay.h>
+#include <linux/module.h>
+#include <linux/marker.h>
+#include <linux/gfp.h>
+#include <linux/kmemtrace.h>
+
+#define KMEMTRACE_SUBBUF_SIZE 524288
+#define KMEMTRACE_DEF_N_SUBBUFS 20
+
+static struct rchan *kmemtrace_chan;
+static u32 kmemtrace_buf_overruns;
+
+static unsigned int kmemtrace_n_subbufs;
+#ifdef CONFIG_KMEMTRACE_DEFAULT_ENABLED
+static unsigned int kmemtrace_enabled = 1;
+#else
+static unsigned int kmemtrace_enabled = 0;
+#endif
+
+/*
+ * The sequence number is used for reordering kmemtrace packets
+ * in userspace, since they are logged as per-CPU data.
+ *
+ * atomic_t should always be a 32-bit signed integer. Wraparound is not
+ * likely to occur, but userspace can deal with it by expecting a certain
+ * sequence number in the next packet that will be read.
+ */
+static atomic_t kmemtrace_seq_num;
+
+#define KMEMTRACE_ABI_VERSION 1
+
+static u32 kmemtrace_abi_version __read_mostly = KMEMTRACE_ABI_VERSION;
+
+enum kmemtrace_event_id {
+ KMEMTRACE_EVENT_ALLOC = 0,
+ KMEMTRACE_EVENT_FREE,
+};
+
+struct kmemtrace_event {
+ u8 event_id;
+ u8 type_id;
+ u16 event_size;
+ s32 seq_num;
+ u64 call_site;
+ u64 ptr;
+} __attribute__ ((__packed__));
+
+struct kmemtrace_stats_alloc {
+ u64 bytes_req;
+ u64 bytes_alloc;
+ u32 gfp_flags;
+ s32 numa_node;
+} __attribute__ ((__packed__));
+
+static void kmemtrace_probe_alloc(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ unsigned long flags;
+ struct kmemtrace_event *ev;
+ struct kmemtrace_stats_alloc *stats;
+ void *buf;
+
+ local_irq_save(flags);
+
+ buf = relay_reserve(kmemtrace_chan,
+ sizeof(struct kmemtrace_event) +
+ sizeof(struct kmemtrace_stats_alloc));
+ if (!buf)
+ goto failed;
+
+ /*
+ * Don't convert this to use structure initializers,
+ * C99 does not guarantee the rvalues evaluation order.
+ */
+
+ ev = buf;
+ ev->event_id = KMEMTRACE_EVENT_ALLOC;
+ ev->type_id = va_arg(*args, int);
+ ev->event_size = sizeof(struct kmemtrace_event) +
+ sizeof(struct kmemtrace_stats_alloc);
+ ev->seq_num = atomic_add_return(1, &kmemtrace_seq_num);
+ ev->call_site = va_arg(*args, unsigned long);
+ ev->ptr = va_arg(*args, unsigned long);
+
+ stats = buf + sizeof(struct kmemtrace_event);
+ stats->bytes_req = va_arg(*args, unsigned long);
+ stats->bytes_alloc = va_arg(*args, unsigned long);
+ stats->gfp_flags = va_arg(*args, unsigned long);
+ stats->numa_node = va_arg(*args, int);
+
+failed:
+ local_irq_restore(flags);
+}
+
+static void kmemtrace_probe_free(void *probe_data, void *call_data,
+ const char *format, va_list *args)
+{
+ unsigned long flags;
+ struct kmemtrace_event *ev;
+
+ local_irq_save(flags);
+
+ ev = relay_reserve(kmemtrace_chan, sizeof(struct kmemtrace_event));
+ if (!ev)
+ goto failed;
+
+ /*
+ * Don't convert this to use structure initializers,
+ * C99 does not guarantee the rvalues evaluation order.
+ */
+ ev->event_id = KMEMTRACE_EVENT_FREE;
+ ev->type_id = va_arg(*args, int);
+ ev->event_size = sizeof(struct kmemtrace_event);
+ ev->seq_num = atomic_add_return(1, &kmemtrace_seq_num);
+ ev->call_site = va_arg(*args, unsigned long);
+ ev->ptr = va_arg(*args, unsigned long);
+
+failed:
+ local_irq_restore(flags);
+}
+
+static struct dentry *
+kmemtrace_create_buf_file(const char *filename, struct dentry *parent,
+ int mode, struct rchan_buf *buf, int *is_global)
+{
+ return debugfs_create_file(filename, mode, parent, buf,
+ &relay_file_operations);
+}
+
+static int kmemtrace_remove_buf_file(struct dentry *dentry)
+{
+ debugfs_remove(dentry);
+
+ return 0;
+}
+
+static int kmemtrace_subbuf_start(struct rchan_buf *buf,
+ void *subbuf,
+ void *prev_subbuf,
+ size_t prev_padding)
+{
+ if (relay_buf_full(buf)) {
+ /*
+ * We know it's not SMP-safe, but neither
+ * debugfs_create_u32() is.
+ */
+ kmemtrace_buf_overruns++;
+ return 0;
+ }
+
+ return 1;
+}
+
+static struct rchan_callbacks relay_callbacks = {
+ .create_buf_file = kmemtrace_create_buf_file,
+ .remove_buf_file = kmemtrace_remove_buf_file,
+ .subbuf_start = kmemtrace_subbuf_start,
+};
+
+static struct dentry *kmemtrace_dir;
+static struct dentry *kmemtrace_overruns_dentry;
+static struct dentry *kmemtrace_abi_version_dentry;
+
+static struct dentry *kmemtrace_enabled_dentry;
+
+static int kmemtrace_start_probes(void)
+{
+ int err;
+
+ err = marker_probe_register("kmemtrace_alloc", "type_id %d "
+ "call_site %lu ptr %lu "
+ "bytes_req %lu bytes_alloc %lu "
+ "gfp_flags %lu node %d",
+ kmemtrace_probe_alloc, NULL);
+ if (err)
+ return err;
+ err = marker_probe_register("kmemtrace_free", "type_id %d "
+ "call_site %lu ptr %lu",
+ kmemtrace_probe_free, NULL);
+
+ return err;
+}
+
+static void kmemtrace_stop_probes(void)
+{
+ marker_probe_unregister("kmemtrace_alloc",
+ kmemtrace_probe_alloc, NULL);
+ marker_probe_unregister("kmemtrace_free",
+ kmemtrace_probe_free, NULL);
+}
+
+static int kmemtrace_enabled_get(void *data, u64 *val)
+{
+ *val = *((int *) data);
+
+ return 0;
+}
+
+static int kmemtrace_enabled_set(void *data, u64 val)
+{
+ u64 old_val = kmemtrace_enabled;
+
+ *((int *) data) = !!val;
+
+ if (old_val == val)
+ return 0;
+ if (val)
+ kmemtrace_start_probes();
+ else
+ kmemtrace_stop_probes();
+
+ return 0;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(kmemtrace_enabled_fops,
+ kmemtrace_enabled_get,
+ kmemtrace_enabled_set, "%llu\n");
+
+static void kmemtrace_cleanup(void)
+{
+ if (kmemtrace_enabled_dentry)
+ debugfs_remove(kmemtrace_enabled_dentry);
+
+ kmemtrace_stop_probes();
+
+ if (kmemtrace_abi_version_dentry)
+ debugfs_remove(kmemtrace_abi_version_dentry);
+ if (kmemtrace_overruns_dentry)
+ debugfs_remove(kmemtrace_overruns_dentry);
+
+ relay_close(kmemtrace_chan);
+ kmemtrace_chan = NULL;
+
+ if (kmemtrace_dir)
+ debugfs_remove(kmemtrace_dir);
+}
+
+static int __init kmemtrace_setup_late(void)
+{
+ if (!kmemtrace_chan)
+ goto failed;
+
+ kmemtrace_dir = debugfs_create_dir("kmemtrace", NULL);
+ if (!kmemtrace_dir)
+ goto cleanup;
+
+ kmemtrace_abi_version_dentry =
+ debugfs_create_u32("abi_version", S_IRUSR,
+ kmemtrace_dir, &kmemtrace_abi_version);
+ kmemtrace_overruns_dentry =
+ debugfs_create_u32("total_overruns", S_IRUSR,
+ kmemtrace_dir, &kmemtrace_buf_overruns);
+ if (!kmemtrace_overruns_dentry || !kmemtrace_abi_version_dentry)
+ goto cleanup;
+
+ kmemtrace_enabled_dentry =
+ debugfs_create_file("enabled", S_IRUSR | S_IWUSR,
+ kmemtrace_dir, &kmemtrace_enabled,
+ &kmemtrace_enabled_fops);
+ if (!kmemtrace_enabled_dentry)
+ goto cleanup;
+
+ if (relay_late_setup_files(kmemtrace_chan, "cpu", kmemtrace_dir))
+ goto cleanup;
+
+ printk(KERN_INFO "kmemtrace: fully up.\n");
+
+ return 0;
+
+cleanup:
+ kmemtrace_cleanup();
+failed:
+ return 1;
+}
+late_initcall(kmemtrace_setup_late);
+
+static int __init kmemtrace_set_boot_enabled(char *str)
+{
+ if (!str)
+ return -EINVAL;
+
+ if (!strcmp(str, "yes"))
+ kmemtrace_enabled = 1;
+ else if (!strcmp(str, "no"))
+ kmemtrace_enabled = 0;
+ else
+ return -EINVAL;
+
+ return 0;
+}
+early_param("kmemtrace.enable", kmemtrace_set_boot_enabled);
+
+static int __init kmemtrace_set_subbufs(char *str)
+{
+ get_option(&str, &kmemtrace_n_subbufs);
+ return 0;
+}
+early_param("kmemtrace.subbufs", kmemtrace_set_subbufs);
+
+void kmemtrace_init(void)
+{
+ if (!kmemtrace_enabled)
+ return;
+
+ if (!kmemtrace_n_subbufs)
+ kmemtrace_n_subbufs = KMEMTRACE_DEF_N_SUBBUFS;
+
+ kmemtrace_chan = relay_open(NULL, NULL, KMEMTRACE_SUBBUF_SIZE,
+ kmemtrace_n_subbufs, &relay_callbacks,
+ NULL);
+ if (unlikely(!kmemtrace_chan)) {
+ printk(KERN_ERR "kmemtrace: could not open relay channel.\n");
+ return;
+ }
+
+ if (unlikely(kmemtrace_start_probes()))
+ goto probe_fail;
+
+ printk(KERN_INFO "kmemtrace: early init successful.\n");
+
+ return;
+
+probe_fail:
+ printk(KERN_ERR "kmemtrace: could not register marker probes!\n");
+ kmemtrace_cleanup();
+}
+
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