kmemtrace: Remove the relay version of kmemtrace

Impact: cleanup

kmemtrace now uses ftrace. This patch removes the relay version.
Signed-off-by: NEduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

kernel/trace/Kconfig

@@ -267,8 +267,6 @@ config HW_BRANCH_TRACER
 config KMEMTRACE
 	bool "Trace SLAB allocations"
 	select TRACING
-	select MARKERS
-	select RELAY
 	help
 	  kmemtrace provides tracing for slab allocator functions, such as
 	  kmalloc, kfree, kmem_cache_alloc, kmem_cache_free etc.. Collected

mm/Makefile

@@ -35,4 +35,3 @@ 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

mm/kmemtrace.c

-/*
- * 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 <trace/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;
-
-/* disabled by default */
-static unsigned int kmemtrace_enabled;
-
-/*
- * 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_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 (!kmemtrace_chan) {
-		printk(KERN_ERR "kmemtrace: could not open relay channel.\n");
-		return;
-	}
-
-	if (!kmemtrace_enabled) {
-		printk(KERN_INFO "kmemtrace: disabled. Pass "
-			"kemtrace.enable=yes as kernel parameter for "
-			"boot-time tracing.\n");
-		return;
-	}
-	if (kmemtrace_start_probes()) {
-		printk(KERN_ERR "kmemtrace: could not register marker probes!\n");
-		kmemtrace_cleanup();
-		return;
-	}
-
-	printk(KERN_INFO "kmemtrace: enabled.\n");
-}
-