diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-06 09:30:52 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2010-08-06 09:30:52 -0700 |
commit | 4aed2fd8e3181fea7c09ba79cf64e7e3f4413bf9 (patch) | |
tree | 1f69733e5daab4915a76a41de0e4d1dc61e12cfb /kernel/trace/trace_ksym.c | |
parent | 3a3527b6461b1298cc53ce72f336346739297ac8 (diff) | |
parent | fc9ea5a1e53ee54f681e226d735008e2a6f8f470 (diff) |
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (162 commits)
tracing/kprobes: unregister_trace_probe needs to be called under mutex
perf: expose event__process function
perf events: Fix mmap offset determination
perf, powerpc: fsl_emb: Restore setting perf_sample_data.period
perf, powerpc: Convert the FSL driver to use local64_t
perf tools: Don't keep unreferenced maps when unmaps are detected
perf session: Invalidate last_match when removing threads from rb_tree
perf session: Free the ref_reloc_sym memory at the right place
x86,mmiotrace: Add support for tracing STOS instruction
perf, sched migration: Librarize task states and event headers helpers
perf, sched migration: Librarize the GUI class
perf, sched migration: Make the GUI class client agnostic
perf, sched migration: Make it vertically scrollable
perf, sched migration: Parameterize cpu height and spacing
perf, sched migration: Fix key bindings
perf, sched migration: Ignore unhandled task states
perf, sched migration: Handle ignored migrate out events
perf: New migration tool overview
tracing: Drop cpparg() macro
perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call
...
Fix up trivial conflicts in Makefile and drivers/cpufreq/cpufreq.c
Diffstat (limited to 'kernel/trace/trace_ksym.c')
-rw-r--r-- | kernel/trace/trace_ksym.c | 508 |
1 files changed, 0 insertions, 508 deletions
diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c deleted file mode 100644 index 8eaf00749b6..00000000000 --- a/kernel/trace/trace_ksym.c +++ /dev/null @@ -1,508 +0,0 @@ -/* - * trace_ksym.c - Kernel Symbol Tracer - * - * 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 - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * - * Copyright (C) IBM Corporation, 2009 - */ - -#include <linux/kallsyms.h> -#include <linux/uaccess.h> -#include <linux/debugfs.h> -#include <linux/ftrace.h> -#include <linux/module.h> -#include <linux/slab.h> -#include <linux/fs.h> - -#include "trace_output.h" -#include "trace.h" - -#include <linux/hw_breakpoint.h> -#include <asm/hw_breakpoint.h> - -#include <asm/atomic.h> - -#define KSYM_TRACER_OP_LEN 3 /* rw- */ - -struct trace_ksym { - struct perf_event **ksym_hbp; - struct perf_event_attr attr; -#ifdef CONFIG_PROFILE_KSYM_TRACER - atomic64_t counter; -#endif - struct hlist_node ksym_hlist; -}; - -static struct trace_array *ksym_trace_array; - -static unsigned int ksym_tracing_enabled; - -static HLIST_HEAD(ksym_filter_head); - -static DEFINE_MUTEX(ksym_tracer_mutex); - -#ifdef CONFIG_PROFILE_KSYM_TRACER - -#define MAX_UL_INT 0xffffffff - -void ksym_collect_stats(unsigned long hbp_hit_addr) -{ - struct hlist_node *node; - struct trace_ksym *entry; - - rcu_read_lock(); - hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) { - if (entry->attr.bp_addr == hbp_hit_addr) { - atomic64_inc(&entry->counter); - break; - } - } - rcu_read_unlock(); -} -#endif /* CONFIG_PROFILE_KSYM_TRACER */ - -void ksym_hbp_handler(struct perf_event *hbp, int nmi, - struct perf_sample_data *data, - struct pt_regs *regs) -{ - struct ring_buffer_event *event; - struct ksym_trace_entry *entry; - struct ring_buffer *buffer; - int pc; - - if (!ksym_tracing_enabled) - return; - - buffer = ksym_trace_array->buffer; - - pc = preempt_count(); - - event = trace_buffer_lock_reserve(buffer, TRACE_KSYM, - sizeof(*entry), 0, pc); - if (!event) - return; - - entry = ring_buffer_event_data(event); - entry->ip = instruction_pointer(regs); - entry->type = hw_breakpoint_type(hbp); - entry->addr = hw_breakpoint_addr(hbp); - strlcpy(entry->cmd, current->comm, TASK_COMM_LEN); - -#ifdef CONFIG_PROFILE_KSYM_TRACER - ksym_collect_stats(hw_breakpoint_addr(hbp)); -#endif /* CONFIG_PROFILE_KSYM_TRACER */ - - trace_buffer_unlock_commit(buffer, event, 0, pc); -} - -/* Valid access types are represented as - * - * rw- : Set Read/Write Access Breakpoint - * -w- : Set Write Access Breakpoint - * --- : Clear Breakpoints - * --x : Set Execution Break points (Not available yet) - * - */ -static int ksym_trace_get_access_type(char *str) -{ - int access = 0; - - if (str[0] == 'r') - access |= HW_BREAKPOINT_R; - - if (str[1] == 'w') - access |= HW_BREAKPOINT_W; - - if (str[2] == 'x') - access |= HW_BREAKPOINT_X; - - switch (access) { - case HW_BREAKPOINT_R: - case HW_BREAKPOINT_W: - case HW_BREAKPOINT_W | HW_BREAKPOINT_R: - return access; - default: - return -EINVAL; - } -} - -/* - * There can be several possible malformed requests and we attempt to capture - * all of them. We enumerate some of the rules - * 1. We will not allow kernel symbols with ':' since it is used as a delimiter. - * i.e. multiple ':' symbols disallowed. Possible uses are of the form - * <module>:<ksym_name>:<op>. - * 2. No delimiter symbol ':' in the input string - * 3. Spurious operator symbols or symbols not in their respective positions - * 4. <ksym_name>:--- i.e. clear breakpoint request when ksym_name not in file - * 5. Kernel symbol not a part of /proc/kallsyms - * 6. Duplicate requests - */ -static int parse_ksym_trace_str(char *input_string, char **ksymname, - unsigned long *addr) -{ - int ret; - - *ksymname = strsep(&input_string, ":"); - *addr = kallsyms_lookup_name(*ksymname); - - /* Check for malformed request: (2), (1) and (5) */ - if ((!input_string) || - (strlen(input_string) != KSYM_TRACER_OP_LEN) || - (*addr == 0)) - return -EINVAL;; - - ret = ksym_trace_get_access_type(input_string); - - return ret; -} - -int process_new_ksym_entry(char *ksymname, int op, unsigned long addr) -{ - struct trace_ksym *entry; - int ret = -ENOMEM; - - entry = kzalloc(sizeof(struct trace_ksym), GFP_KERNEL); - if (!entry) - return -ENOMEM; - - hw_breakpoint_init(&entry->attr); - - entry->attr.bp_type = op; - entry->attr.bp_addr = addr; - entry->attr.bp_len = HW_BREAKPOINT_LEN_4; - - entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr, - ksym_hbp_handler); - - if (IS_ERR(entry->ksym_hbp)) { - ret = PTR_ERR(entry->ksym_hbp); - if (ret == -ENOSPC) { - printk(KERN_ERR "ksym_tracer: Maximum limit reached." - " No new requests for tracing can be accepted now.\n"); - } else { - printk(KERN_INFO "ksym_tracer request failed. Try again" - " later!!\n"); - } - goto err; - } - - hlist_add_head_rcu(&(entry->ksym_hlist), &ksym_filter_head); - - return 0; - -err: - kfree(entry); - - return ret; -} - -static ssize_t ksym_trace_filter_read(struct file *filp, char __user *ubuf, - size_t count, loff_t *ppos) -{ - struct trace_ksym *entry; - struct hlist_node *node; - struct trace_seq *s; - ssize_t cnt = 0; - int ret; - - s = kmalloc(sizeof(*s), GFP_KERNEL); - if (!s) - return -ENOMEM; - trace_seq_init(s); - - mutex_lock(&ksym_tracer_mutex); - - hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) { - ret = trace_seq_printf(s, "%pS:", - (void *)(unsigned long)entry->attr.bp_addr); - if (entry->attr.bp_type == HW_BREAKPOINT_R) - ret = trace_seq_puts(s, "r--\n"); - else if (entry->attr.bp_type == HW_BREAKPOINT_W) - ret = trace_seq_puts(s, "-w-\n"); - else if (entry->attr.bp_type == (HW_BREAKPOINT_W | HW_BREAKPOINT_R)) - ret = trace_seq_puts(s, "rw-\n"); - WARN_ON_ONCE(!ret); - } - - cnt = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); - - mutex_unlock(&ksym_tracer_mutex); - - kfree(s); - - return cnt; -} - -static void __ksym_trace_reset(void) -{ - struct trace_ksym *entry; - struct hlist_node *node, *node1; - - mutex_lock(&ksym_tracer_mutex); - hlist_for_each_entry_safe(entry, node, node1, &ksym_filter_head, - ksym_hlist) { - unregister_wide_hw_breakpoint(entry->ksym_hbp); - hlist_del_rcu(&(entry->ksym_hlist)); - synchronize_rcu(); - kfree(entry); - } - mutex_unlock(&ksym_tracer_mutex); -} - -static ssize_t ksym_trace_filter_write(struct file *file, - const char __user *buffer, - size_t count, loff_t *ppos) -{ - struct trace_ksym *entry; - struct hlist_node *node; - char *buf, *input_string, *ksymname = NULL; - unsigned long ksym_addr = 0; - int ret, op, changed = 0; - - buf = kzalloc(count + 1, GFP_KERNEL); - if (!buf) - return -ENOMEM; - - ret = -EFAULT; - if (copy_from_user(buf, buffer, count)) - goto out; - - buf[count] = '\0'; - input_string = strstrip(buf); - - /* - * Clear all breakpoints if: - * 1: echo > ksym_trace_filter - * 2: echo 0 > ksym_trace_filter - * 3: echo "*:---" > ksym_trace_filter - */ - if (!input_string[0] || !strcmp(input_string, "0") || - !strcmp(input_string, "*:---")) { - __ksym_trace_reset(); - ret = 0; - goto out; - } - - ret = op = parse_ksym_trace_str(input_string, &ksymname, &ksym_addr); - if (ret < 0) - goto out; - - mutex_lock(&ksym_tracer_mutex); - - ret = -EINVAL; - hlist_for_each_entry(entry, node, &ksym_filter_head, ksym_hlist) { - if (entry->attr.bp_addr == ksym_addr) { - /* Check for malformed request: (6) */ - if (entry->attr.bp_type != op) - changed = 1; - else - goto out_unlock; - break; - } - } - if (changed) { - unregister_wide_hw_breakpoint(entry->ksym_hbp); - entry->attr.bp_type = op; - ret = 0; - if (op > 0) { - entry->ksym_hbp = - register_wide_hw_breakpoint(&entry->attr, - ksym_hbp_handler); - if (IS_ERR(entry->ksym_hbp)) - ret = PTR_ERR(entry->ksym_hbp); - else - goto out_unlock; - } - /* Error or "symbol:---" case: drop it */ - hlist_del_rcu(&(entry->ksym_hlist)); - synchronize_rcu(); - kfree(entry); - goto out_unlock; - } else { - /* Check for malformed request: (4) */ - if (op) - ret = process_new_ksym_entry(ksymname, op, ksym_addr); - } -out_unlock: - mutex_unlock(&ksym_tracer_mutex); -out: - kfree(buf); - return !ret ? count : ret; -} - -static const struct file_operations ksym_tracing_fops = { - .open = tracing_open_generic, - .read = ksym_trace_filter_read, - .write = ksym_trace_filter_write, -}; - -static void ksym_trace_reset(struct trace_array *tr) -{ - ksym_tracing_enabled = 0; - __ksym_trace_reset(); -} - -static int ksym_trace_init(struct trace_array *tr) -{ - int cpu, ret = 0; - - for_each_online_cpu(cpu) - tracing_reset(tr, cpu); - ksym_tracing_enabled = 1; - ksym_trace_array = tr; - - return ret; -} - -static void ksym_trace_print_header(struct seq_file *m) -{ - seq_puts(m, - "# TASK-PID CPU# Symbol " - "Type Function\n"); - seq_puts(m, - "# | | | " - " | |\n"); -} - -static enum print_line_t ksym_trace_output(struct trace_iterator *iter) -{ - struct trace_entry *entry = iter->ent; - struct trace_seq *s = &iter->seq; - struct ksym_trace_entry *field; - char str[KSYM_SYMBOL_LEN]; - int ret; - - if (entry->type != TRACE_KSYM) - return TRACE_TYPE_UNHANDLED; - - trace_assign_type(field, entry); - - ret = trace_seq_printf(s, "%11s-%-5d [%03d] %pS", field->cmd, - entry->pid, iter->cpu, (char *)field->addr); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - switch (field->type) { - case HW_BREAKPOINT_R: - ret = trace_seq_printf(s, " R "); - break; - case HW_BREAKPOINT_W: - ret = trace_seq_printf(s, " W "); - break; - case HW_BREAKPOINT_R | HW_BREAKPOINT_W: - ret = trace_seq_printf(s, " RW "); - break; - default: - return TRACE_TYPE_PARTIAL_LINE; - } - - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - sprint_symbol(str, field->ip); - ret = trace_seq_printf(s, "%s\n", str); - if (!ret) - return TRACE_TYPE_PARTIAL_LINE; - - return TRACE_TYPE_HANDLED; -} - -struct tracer ksym_tracer __read_mostly = -{ - .name = "ksym_tracer", - .init = ksym_trace_init, - .reset = ksym_trace_reset, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_ksym, -#endif - .print_header = ksym_trace_print_header, - .print_line = ksym_trace_output -}; - -#ifdef CONFIG_PROFILE_KSYM_TRACER -static int ksym_profile_show(struct seq_file *m, void *v) -{ - struct hlist_node *node; - struct trace_ksym *entry; - int access_type = 0; - char fn_name[KSYM_NAME_LEN]; - - seq_puts(m, " Access Type "); - seq_puts(m, " Symbol Counter\n"); - seq_puts(m, " ----------- "); - seq_puts(m, " ------ -------\n"); - - rcu_read_lock(); - hlist_for_each_entry_rcu(entry, node, &ksym_filter_head, ksym_hlist) { - - access_type = entry->attr.bp_type; - - switch (access_type) { - case HW_BREAKPOINT_R: - seq_puts(m, " R "); - break; - case HW_BREAKPOINT_W: - seq_puts(m, " W "); - break; - case HW_BREAKPOINT_R | HW_BREAKPOINT_W: - seq_puts(m, " RW "); - break; - default: - seq_puts(m, " NA "); - } - - if (lookup_symbol_name(entry->attr.bp_addr, fn_name) >= 0) - seq_printf(m, " %-36s", fn_name); - else - seq_printf(m, " %-36s", "<NA>"); - seq_printf(m, " %15llu\n", - (unsigned long long)atomic64_read(&entry->counter)); - } - rcu_read_unlock(); - - return 0; -} - -static int ksym_profile_open(struct inode *node, struct file *file) -{ - return single_open(file, ksym_profile_show, NULL); -} - -static const struct file_operations ksym_profile_fops = { - .open = ksym_profile_open, - .read = seq_read, - .llseek = seq_lseek, - .release = single_release, -}; -#endif /* CONFIG_PROFILE_KSYM_TRACER */ - -__init static int init_ksym_trace(void) -{ - struct dentry *d_tracer; - - d_tracer = tracing_init_dentry(); - - trace_create_file("ksym_trace_filter", 0644, d_tracer, - NULL, &ksym_tracing_fops); - -#ifdef CONFIG_PROFILE_KSYM_TRACER - trace_create_file("ksym_profile", 0444, d_tracer, - NULL, &ksym_profile_fops); -#endif - - return register_tracer(&ksym_tracer); -} -device_initcall(init_ksym_trace); |