summaryrefslogtreecommitdiffstats
path: root/kernel/trace
diff options
context:
space:
mode:
authorFrederic Weisbecker <fweisbec@gmail.com>2008-12-29 13:42:23 -0800
committerIngo Molnar <mingo@elte.hu>2008-12-30 09:36:13 +0100
commit36994e58a48fb8f9651c7dc845a6de298aba5bfc (patch)
treefac4b8a1c30560e91460651487f3a57ef7f2b5cc /kernel/trace
parent7a51cffbd10886c0557677dd916c090097c691ef (diff)
tracing/kmemtrace: normalize the raw tracer event to the unified tracing API
Impact: new tracer plugin This patch adapts kmemtrace raw events tracing to the unified tracing API. To enable and use this tracer, just do the following: echo kmemtrace > /debugfs/tracing/current_tracer cat /debugfs/tracing/trace You will have the following output: # tracer: kmemtrace # # # ALLOC TYPE REQ GIVEN FLAGS POINTER NODE CALLER # FREE | | | | | | | | # | type_id 1 call_site 18446744071565527833 ptr 18446612134395152256 type_id 0 call_site 18446744071565585597 ptr 18446612134405955584 bytes_req 4096 bytes_alloc 4096 gfp_flags 208 node -1 type_id 1 call_site 18446744071565585534 ptr 18446612134405955584 type_id 0 call_site 18446744071565585597 ptr 18446612134405955584 bytes_req 4096 bytes_alloc 4096 gfp_flags 208 node -1 type_id 0 call_site 18446744071565636711 ptr 18446612134345164672 bytes_req 240 bytes_alloc 240 gfp_flags 208 node -1 type_id 1 call_site 18446744071565585534 ptr 18446612134405955584 type_id 0 call_site 18446744071565585597 ptr 18446612134405955584 bytes_req 4096 bytes_alloc 4096 gfp_flags 208 node -1 type_id 0 call_site 18446744071565636711 ptr 18446612134345164912 bytes_req 240 bytes_alloc 240 gfp_flags 208 node -1 type_id 1 call_site 18446744071565585534 ptr 18446612134405955584 type_id 0 call_site 18446744071565585597 ptr 18446612134405955584 bytes_req 4096 bytes_alloc 4096 gfp_flags 208 node -1 type_id 0 call_site 18446744071565636711 ptr 18446612134345165152 bytes_req 240 bytes_alloc 240 gfp_flags 208 node -1 type_id 0 call_site 18446744071566144042 ptr 18446612134346191680 bytes_req 1304 bytes_alloc 1312 gfp_flags 208 node -1 type_id 1 call_site 18446744071565585534 ptr 18446612134405955584 type_id 0 call_site 18446744071565585597 ptr 18446612134405955584 bytes_req 4096 bytes_alloc 4096 gfp_flags 208 node -1 type_id 1 call_site 18446744071565585534 ptr 18446612134405955584 That was to stay backward compatible with the format output produced in inux/tracepoint.h. This is the default ouput, but note that I tried something else. If you change an option: echo kmem_minimalistic > /debugfs/trace_options and then cat /debugfs/trace, you will have the following output: # tracer: kmemtrace # # # ALLOC TYPE REQ GIVEN FLAGS POINTER NODE CALLER # FREE | | | | | | | | # | - C 0xffff88007c088780 file_free_rcu + K 4096 4096 000000d0 0xffff88007cad6000 -1 getname - C 0xffff88007cad6000 putname + K 4096 4096 000000d0 0xffff88007cad6000 -1 getname + K 240 240 000000d0 0xffff8800790dc780 -1 d_alloc - C 0xffff88007cad6000 putname + K 4096 4096 000000d0 0xffff88007cad6000 -1 getname + K 240 240 000000d0 0xffff8800790dc870 -1 d_alloc - C 0xffff88007cad6000 putname + K 4096 4096 000000d0 0xffff88007cad6000 -1 getname + K 240 240 000000d0 0xffff8800790dc960 -1 d_alloc + K 1304 1312 000000d0 0xffff8800791d7340 -1 reiserfs_alloc_inode - C 0xffff88007cad6000 putname + K 4096 4096 000000d0 0xffff88007cad6000 -1 getname - C 0xffff88007cad6000 putname + K 992 1000 000000d0 0xffff880079045b58 -1 alloc_inode + K 768 1024 000080d0 0xffff88007c096400 -1 alloc_pipe_info + K 240 240 000000d0 0xffff8800790dca50 -1 d_alloc + K 272 320 000080d0 0xffff88007c088780 -1 get_empty_filp + K 272 320 000080d0 0xffff88007c088000 -1 get_empty_filp Yeah I shall confess kmem_minimalistic should be: kmem_alternative. Whatever, I find it more readable but this a personal opinion of course. We can drop it if you want. On the ALLOC/FREE column, + means an allocation and - a free. On the type column, you have K = kmalloc, C = cache, P = page I would like the flags to be GFP_* strings but that would not be easy to not break the column with strings.... About the node...it seems to always be -1. I don't know why but that shouldn't be difficult to find. I moved linux/tracepoint.h to trace/tracepoint.h as well. I think that would be more easy to find the tracer headers if they are all in their common directory. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/Kconfig22
-rw-r--r--kernel/trace/Makefile1
-rw-r--r--kernel/trace/kmemtrace.c343
-rw-r--r--kernel/trace/trace.h25
4 files changed, 391 insertions, 0 deletions
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index e2a4ff6fc3a..27fb74b06b3 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -264,6 +264,28 @@ config HW_BRANCH_TRACER
This tracer records all branches on the system in a circular
buffer giving access to the last N branches for each cpu.
+config KMEMTRACE
+ bool "Trace SLAB allocations"
+ select TRACING
+ depends on RELAY
+ 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 DYNAMIC_FTRACE
bool "enable/disable ftrace tracepoints dynamically"
depends on FUNCTION_TRACER
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index 349d5a93653..513dc86b5df 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -33,5 +33,6 @@ obj-$(CONFIG_FUNCTION_GRAPH_TRACER) += trace_functions_graph.o
obj-$(CONFIG_TRACE_BRANCH_PROFILING) += trace_branch.o
obj-$(CONFIG_HW_BRANCH_TRACER) += trace_hw_branches.o
obj-$(CONFIG_POWER_TRACER) += trace_power.o
+obj-$(CONFIG_KMEMTRACE) += kmemtrace.o
libftrace-y := ftrace.o
diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c
new file mode 100644
index 00000000000..d69cbe3c2a4
--- /dev/null
+++ b/kernel/trace/kmemtrace.c
@@ -0,0 +1,343 @@
+/*
+ * Memory allocator tracing
+ *
+ * Copyright (C) 2008 Eduard - Gabriel Munteanu
+ * Copyright (C) 2008 Pekka Enberg <penberg@cs.helsinki.fi>
+ * Copyright (C) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ */
+
+#include <linux/dcache.h>
+#include <linux/debugfs.h>
+#include <linux/fs.h>
+#include <linux/seq_file.h>
+#include <trace/kmemtrace.h>
+
+#include "trace.h"
+#include "trace_output.h"
+
+/* Select an alternative, minimalistic output than the original one */
+#define TRACE_KMEM_OPT_MINIMAL 0x1
+
+static struct tracer_opt kmem_opts[] = {
+ /* Default disable the minimalistic output */
+ { TRACER_OPT(kmem_minimalistic, TRACE_KMEM_OPT_MINIMAL) },
+ { }
+};
+
+static struct tracer_flags kmem_tracer_flags = {
+ .val = 0,
+ .opts = kmem_opts
+};
+
+
+static bool kmem_tracing_enabled __read_mostly;
+static struct trace_array *kmemtrace_array;
+
+static int kmem_trace_init(struct trace_array *tr)
+{
+ int cpu;
+ kmemtrace_array = tr;
+
+ for_each_cpu_mask(cpu, cpu_possible_map)
+ tracing_reset(tr, cpu);
+
+ kmem_tracing_enabled = true;
+
+ return 0;
+}
+
+static void kmem_trace_reset(struct trace_array *tr)
+{
+ kmem_tracing_enabled = false;
+}
+
+static void kmemtrace_headers(struct seq_file *s)
+{
+ /* Don't need headers for the original kmemtrace output */
+ if (!(kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL))
+ return;
+
+ seq_printf(s, "#\n");
+ seq_printf(s, "# ALLOC TYPE REQ GIVEN FLAGS "
+ " POINTER NODE CALLER\n");
+ seq_printf(s, "# FREE | | | | "
+ " | | | |\n");
+ seq_printf(s, "# |\n\n");
+}
+
+/*
+ * The two following functions give the original output from kmemtrace,
+ * or something close to....perhaps they need some missing things
+ */
+static enum print_line_t
+kmemtrace_print_alloc_original(struct trace_iterator *iter,
+ struct kmemtrace_alloc_entry *entry)
+{
+ struct trace_seq *s = &iter->seq;
+ int ret;
+
+ /* Taken from the old linux/kmemtrace.h */
+ ret = trace_seq_printf(s, "type_id %d call_site %lu ptr %lu "
+ "bytes_req %lu bytes_alloc %lu gfp_flags %lu node %d\n",
+ entry->type_id, entry->call_site, (unsigned long) entry->ptr,
+ (unsigned long) entry->bytes_req, (unsigned long) entry->bytes_alloc,
+ (unsigned long) entry->gfp_flags, entry->node);
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free_original(struct trace_iterator *iter,
+ struct kmemtrace_free_entry *entry)
+{
+ struct trace_seq *s = &iter->seq;
+ int ret;
+
+ /* Taken from the old linux/kmemtrace.h */
+ ret = trace_seq_printf(s, "type_id %d call_site %lu ptr %lu\n",
+ entry->type_id, entry->call_site, (unsigned long) entry->ptr);
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
+
+/* The two other following provide a more minimalistic output */
+static enum print_line_t
+kmemtrace_print_alloc_compress(struct trace_iterator *iter,
+ struct kmemtrace_alloc_entry *entry)
+{
+ struct trace_seq *s = &iter->seq;
+ int ret;
+
+ /* Alloc entry */
+ ret = trace_seq_printf(s, " + ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Type */
+ switch (entry->type_id) {
+ case KMEMTRACE_TYPE_KMALLOC:
+ ret = trace_seq_printf(s, "K ");
+ break;
+ case KMEMTRACE_TYPE_CACHE:
+ ret = trace_seq_printf(s, "C ");
+ break;
+ case KMEMTRACE_TYPE_PAGES:
+ ret = trace_seq_printf(s, "P ");
+ break;
+ default:
+ ret = trace_seq_printf(s, "? ");
+ }
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Requested */
+ ret = trace_seq_printf(s, "%4d ", entry->bytes_req);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Allocated */
+ ret = trace_seq_printf(s, "%4d ", entry->bytes_alloc);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Flags
+ * TODO: would be better to see the name of the GFP flag names
+ */
+ ret = trace_seq_printf(s, "%08x ", entry->gfp_flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Pointer to allocated */
+ ret = trace_seq_printf(s, "0x%tx ", (ptrdiff_t)entry->ptr);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Node */
+ ret = trace_seq_printf(s, "%4d ", entry->node);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Call site */
+ ret = seq_print_ip_sym(s, entry->call_site, 0);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (!trace_seq_printf(s, "\n"))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+kmemtrace_print_free_compress(struct trace_iterator *iter,
+ struct kmemtrace_free_entry *entry)
+{
+ struct trace_seq *s = &iter->seq;
+ int ret;
+
+ /* Free entry */
+ ret = trace_seq_printf(s, " - ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Type */
+ switch (entry->type_id) {
+ case KMEMTRACE_TYPE_KMALLOC:
+ ret = trace_seq_printf(s, "K ");
+ break;
+ case KMEMTRACE_TYPE_CACHE:
+ ret = trace_seq_printf(s, "C ");
+ break;
+ case KMEMTRACE_TYPE_PAGES:
+ ret = trace_seq_printf(s, "P ");
+ break;
+ default:
+ ret = trace_seq_printf(s, "? ");
+ }
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Skip requested/allocated/flags */
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Pointer to allocated */
+ ret = trace_seq_printf(s, "0x%tx ", (ptrdiff_t)entry->ptr);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Skip node */
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Call site */
+ ret = seq_print_ip_sym(s, entry->call_site, 0);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (!trace_seq_printf(s, "\n"))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t kmemtrace_print_line(struct trace_iterator *iter)
+{
+ struct trace_entry *entry = iter->ent;
+
+ switch (entry->type) {
+ case TRACE_KMEM_ALLOC: {
+ struct kmemtrace_alloc_entry *field;
+ trace_assign_type(field, entry);
+ if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
+ return kmemtrace_print_alloc_compress(iter, field);
+ else
+ return kmemtrace_print_alloc_original(iter, field);
+ }
+
+ case TRACE_KMEM_FREE: {
+ struct kmemtrace_free_entry *field;
+ trace_assign_type(field, entry);
+ if (kmem_tracer_flags.val & TRACE_KMEM_OPT_MINIMAL)
+ return kmemtrace_print_free_compress(iter, field);
+ else
+ return kmemtrace_print_free_original(iter, field);
+ }
+
+ default:
+ return TRACE_TYPE_UNHANDLED;
+ }
+}
+
+/* Trace allocations */
+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)
+{
+ struct ring_buffer_event *event;
+ struct kmemtrace_alloc_entry *entry;
+ struct trace_array *tr = kmemtrace_array;
+ unsigned long irq_flags;
+
+ if (!kmem_tracing_enabled)
+ return;
+
+ event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, 0, 0);
+
+ entry->ent.type = TRACE_KMEM_ALLOC;
+ entry->call_site = call_site;
+ entry->ptr = ptr;
+ entry->bytes_req = bytes_req;
+ entry->bytes_alloc = bytes_alloc;
+ entry->gfp_flags = gfp_flags;
+ entry->node = node;
+
+ ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+
+ trace_wake_up();
+}
+
+void kmemtrace_mark_free(enum kmemtrace_type_id type_id,
+ unsigned long call_site,
+ const void *ptr)
+{
+ struct ring_buffer_event *event;
+ struct kmemtrace_free_entry *entry;
+ struct trace_array *tr = kmemtrace_array;
+ unsigned long irq_flags;
+
+ if (!kmem_tracing_enabled)
+ return;
+
+ event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+ &irq_flags);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ tracing_generic_entry_update(&entry->ent, 0, 0);
+
+ entry->ent.type = TRACE_KMEM_FREE;
+ entry->type_id = type_id;
+ entry->call_site = call_site;
+ entry->ptr = ptr;
+
+ ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+
+ trace_wake_up();
+}
+
+static struct tracer kmem_tracer __read_mostly = {
+ .name = "kmemtrace",
+ .init = kmem_trace_init,
+ .reset = kmem_trace_reset,
+ .print_line = kmemtrace_print_line,
+ .print_header = kmemtrace_headers,
+ .flags = &kmem_tracer_flags
+};
+
+static int __init init_kmem_tracer(void)
+{
+ return register_tracer(&kmem_tracer);
+}
+
+device_initcall(init_kmem_tracer);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index cc7a4f86403..534505bb39b 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -9,6 +9,7 @@
#include <linux/mmiotrace.h>
#include <linux/ftrace.h>
#include <trace/boot.h>
+#include <trace/kmemtrace.h>
enum trace_type {
__TRACE_FIRST_TYPE = 0,
@@ -29,6 +30,8 @@ enum trace_type {
TRACE_GRAPH_ENT,
TRACE_USER_STACK,
TRACE_HW_BRANCHES,
+ TRACE_KMEM_ALLOC,
+ TRACE_KMEM_FREE,
TRACE_POWER,
__TRACE_LAST_TYPE
@@ -170,6 +173,24 @@ struct trace_power {
struct power_trace state_data;
};
+struct kmemtrace_alloc_entry {
+ struct trace_entry ent;
+ 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;
+};
+
+struct kmemtrace_free_entry {
+ struct trace_entry ent;
+ enum kmemtrace_type_id type_id;
+ unsigned long call_site;
+ const void *ptr;
+};
+
/*
* trace_flag_type is an enumeration that holds different
* states when a trace occurs. These are:
@@ -280,6 +301,10 @@ extern void __ftrace_bad_type(void);
TRACE_GRAPH_RET); \
IF_ASSIGN(var, ent, struct hw_branch_entry, TRACE_HW_BRANCHES);\
IF_ASSIGN(var, ent, struct trace_power, TRACE_POWER); \
+ IF_ASSIGN(var, ent, struct kmemtrace_alloc_entry, \
+ TRACE_KMEM_ALLOC); \
+ IF_ASSIGN(var, ent, struct kmemtrace_free_entry, \
+ TRACE_KMEM_FREE); \
__ftrace_bad_type(); \
} while (0)