diff options
| -rw-r--r-- | Documentation/trace/ftrace-design.txt | 7 | ||||
| -rw-r--r-- | Documentation/trace/ftrace.txt | 148 | ||||
| -rw-r--r-- | include/linux/syscalls.h | 10 | ||||
| -rw-r--r-- | kernel/trace/trace.c | 4 | ||||
| -rw-r--r-- | kernel/trace/trace_sched_switch.c | 48 | ||||
| -rw-r--r-- | kernel/trace/trace_syscalls.c | 42 | ||||
| -rw-r--r-- | scripts/kconfig/streamline_config.pl | 2 | ||||
| -rwxr-xr-x | tools/testing/ktest/ktest.pl | 2 |
8 files changed, 68 insertions, 195 deletions
diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt index dc52bd4..79fcafc 100644 --- a/Documentation/trace/ftrace-design.txt +++ b/Documentation/trace/ftrace-design.txt @@ -247,6 +247,13 @@ You need very few things to get the syscalls tracing in an arch. - Support the TIF_SYSCALL_TRACEPOINT thread flags. - Put the trace_sys_enter() and trace_sys_exit() tracepoints calls from ptrace in the ptrace syscalls tracing path. +- If the system call table on this arch is more complicated than a simple array + of addresses of the system calls, implement an arch_syscall_addr to return + the address of a given system call. +- If the symbol names of the system calls do not match the function names on + this arch, define ARCH_HAS_SYSCALL_MATCH_SYM_NAME in asm/ftrace.h and + implement arch_syscall_match_sym_name with the appropriate logic to return + true if the function name corresponds with the symbol name. - Tag this arch as HAVE_SYSCALL_TRACEPOINTS. diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index 557c1ed..67f1cc4 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -80,11 +80,11 @@ of ftrace. Here is a list of some of the key files: tracers listed here can be configured by echoing their name into current_tracer. - tracing_enabled: + tracing_on: - This sets or displays whether the current_tracer - is activated and tracing or not. Echo 0 into this - file to disable the tracer or 1 to enable it. + This sets or displays whether writing to the trace + ring buffer is enabled. Echo 0 into this file to disable + the tracer or 1 to enable it. trace: @@ -202,10 +202,6 @@ Here is the list of current tracers that may be configured. to draw a graph of function calls similar to C code source. - "sched_switch" - - Traces the context switches and wakeups between tasks. - "irqsoff" Traces the areas that disable interrupts and saves @@ -273,39 +269,6 @@ format, the function name that was traced "path_put" and the parent function that called this function "path_walk". The timestamp is the time at which the function was entered. -The sched_switch tracer also includes tracing of task wakeups -and context switches. - - ksoftirqd/1-7 [01] 1453.070013: 7:115:R + 2916:115:S - ksoftirqd/1-7 [01] 1453.070013: 7:115:R + 10:115:S - ksoftirqd/1-7 [01] 1453.070013: 7:115:R ==> 10:115:R - events/1-10 [01] 1453.070013: 10:115:S ==> 2916:115:R - kondemand/1-2916 [01] 1453.070013: 2916:115:S ==> 7:115:R - ksoftirqd/1-7 [01] 1453.070013: 7:115:S ==> 0:140:R - -Wake ups are represented by a "+" and the context switches are -shown as "==>". The format is: - - Context switches: - - Previous task Next Task - - <pid>:<prio>:<state> ==> <pid>:<prio>:<state> - - Wake ups: - - Current task Task waking up - - <pid>:<prio>:<state> + <pid>:<prio>:<state> - -The prio is the internal kernel priority, which is the inverse -of the priority that is usually displayed by user-space tools. -Zero represents the highest priority (99). Prio 100 starts the -"nice" priorities with 100 being equal to nice -20 and 139 being -nice 19. The prio "140" is reserved for the idle task which is -the lowest priority thread (pid 0). - - Latency trace format -------------------- @@ -491,79 +454,6 @@ x494] <- /root/a.out[+0x4a8] <- /lib/libc-2.7.so[+0x1e1a6] latencies, as described in "Latency trace format". -sched_switch ------------- - -This tracer simply records schedule switches. Here is an example -of how to use it. - - # echo sched_switch > current_tracer - # echo 1 > tracing_enabled - # sleep 1 - # echo 0 > tracing_enabled - # cat trace - -# tracer: sched_switch -# -# TASK-PID CPU# TIMESTAMP FUNCTION -# | | | | | - bash-3997 [01] 240.132281: 3997:120:R + 4055:120:R - bash-3997 [01] 240.132284: 3997:120:R ==> 4055:120:R - sleep-4055 [01] 240.132371: 4055:120:S ==> 3997:120:R - bash-3997 [01] 240.132454: 3997:120:R + 4055:120:S - bash-3997 [01] 240.132457: 3997:120:R ==> 4055:120:R - sleep-4055 [01] 240.132460: 4055:120:D ==> 3997:120:R - bash-3997 [01] 240.132463: 3997:120:R + 4055:120:D - bash-3997 [01] 240.132465: 3997:120:R ==> 4055:120:R - <idle>-0 [00] 240.132589: 0:140:R + 4:115:S - <idle>-0 [00] 240.132591: 0:140:R ==> 4:115:R - ksoftirqd/0-4 [00] 240.132595: 4:115:S ==> 0:140:R - <idle>-0 [00] 240.132598: 0:140:R + 4:115:S - <idle>-0 [00] 240.132599: 0:140:R ==> 4:115:R - ksoftirqd/0-4 [00] 240.132603: 4:115:S ==> 0:140:R - sleep-4055 [01] 240.133058: 4055:120:S ==> 3997:120:R - [...] - - -As we have discussed previously about this format, the header -shows the name of the trace and points to the options. The -"FUNCTION" is a misnomer since here it represents the wake ups -and context switches. - -The sched_switch file only lists the wake ups (represented with -'+') and context switches ('==>') with the previous task or -current task first followed by the next task or task waking up. -The format for both of these is PID:KERNEL-PRIO:TASK-STATE. -Remember that the KERNEL-PRIO is the inverse of the actual -priority with zero (0) being the highest priority and the nice -values starting at 100 (nice -20). Below is a quick chart to map -the kernel priority to user land priorities. - - Kernel Space User Space - =============================================================== - 0(high) to 98(low) user RT priority 99(high) to 1(low) - with SCHED_RR or SCHED_FIFO - --------------------------------------------------------------- - 99 sched_priority is not used in scheduling - decisions(it must be specified as 0) - --------------------------------------------------------------- - 100(high) to 139(low) user nice -20(high) to 19(low) - --------------------------------------------------------------- - 140 idle task priority - --------------------------------------------------------------- - -The task states are: - - R - running : wants to run, may not actually be running - S - sleep : process is waiting to be woken up (handles signals) - D - disk sleep (uninterruptible sleep) : process must be woken up - (ignores signals) - T - stopped : process suspended - t - traced : process is being traced (with something like gdb) - Z - zombie : process waiting to be cleaned up - X - unknown - - ftrace_enabled -------------- @@ -607,10 +497,10 @@ an example: # echo irqsoff > current_tracer # echo latency-format > trace_options # echo 0 > tracing_max_latency - # echo 1 > tracing_enabled + # echo 1 > tracing_on # ls -ltr [...] - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: irqsoff # @@ -715,10 +605,10 @@ is much like the irqsoff tracer. # echo preemptoff > current_tracer # echo latency-format > trace_options # echo 0 > tracing_max_latency - # echo 1 > tracing_enabled + # echo 1 > tracing_on # ls -ltr [...] - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: preemptoff # @@ -863,10 +753,10 @@ tracers. # echo preemptirqsoff > current_tracer # echo latency-format > trace_options # echo 0 > tracing_max_latency - # echo 1 > tracing_enabled + # echo 1 > tracing_on # ls -ltr [...] - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: preemptirqsoff # @@ -1026,9 +916,9 @@ Instead of performing an 'ls', we will run 'sleep 1' under # echo wakeup > current_tracer # echo latency-format > trace_options # echo 0 > tracing_max_latency - # echo 1 > tracing_enabled + # echo 1 > tracing_on # chrt -f 5 sleep 1 - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: wakeup # @@ -1140,9 +1030,9 @@ ftrace_enabled is set; otherwise this tracer is a nop. # sysctl kernel.ftrace_enabled=1 # echo function > current_tracer - # echo 1 > tracing_enabled + # echo 1 > tracing_on # usleep 1 - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: function # @@ -1180,7 +1070,7 @@ int trace_fd; [...] int main(int argc, char *argv[]) { [...] - trace_fd = open(tracing_file("tracing_enabled"), O_WRONLY); + trace_fd = open(tracing_file("tracing_on"), O_WRONLY); [...] if (condition_hit()) { write(trace_fd, "0", 1); @@ -1631,9 +1521,9 @@ If I am only interested in sys_nanosleep and hrtimer_interrupt: # echo sys_nanosleep hrtimer_interrupt \ > set_ftrace_filter # echo function > current_tracer - # echo 1 > tracing_enabled + # echo 1 > tracing_on # usleep 1 - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: ftrace # @@ -1879,9 +1769,9 @@ different. The trace is live. # echo function > current_tracer # cat trace_pipe > /tmp/trace.out & [1] 4153 - # echo 1 > tracing_enabled + # echo 1 > tracing_on # usleep 1 - # echo 0 > tracing_enabled + # echo 0 > tracing_on # cat trace # tracer: function # diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 98664db..a17fcea 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -132,11 +132,11 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_enter, \ .event.funcs = &enter_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ + .flags = TRACE_EVENT_FL_CAP_ANY, \ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ - *__event_enter_##sname = &event_enter_##sname; \ - __TRACE_EVENT_FLAGS(enter_##sname, TRACE_EVENT_FL_CAP_ANY) + *__event_enter_##sname = &event_enter_##sname; #define SYSCALL_TRACE_EXIT_EVENT(sname) \ static struct syscall_metadata __syscall_meta_##sname; \ @@ -146,11 +146,11 @@ extern struct trace_event_functions exit_syscall_print_funcs; .class = &event_class_syscall_exit, \ .event.funcs = &exit_syscall_print_funcs, \ .data = (void *)&__syscall_meta_##sname,\ + .flags = TRACE_EVENT_FL_CAP_ANY, \ }; \ static struct ftrace_event_call __used \ __attribute__((section("_ftrace_events"))) \ - *__event_exit_##sname = &event_exit_##sname; \ - __TRACE_EVENT_FLAGS(exit_##sname, TRACE_EVENT_FL_CAP_ANY) + *__event_exit_##sname = &event_exit_##sname; #define SYSCALL_METADATA(sname, nb) \ SYSCALL_TRACE_ENTER_EVENT(sname); \ @@ -158,6 +158,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; static struct syscall_metadata __used \ __syscall_meta_##sname = { \ .name = "sys"#sname, \ + .syscall_nr = -1, /* Filled in at boot */ \ .nb_args = nb, \ .types = types_##sname, \ .args = args_##sname, \ @@ -175,6 +176,7 @@ extern struct trace_event_functions exit_syscall_print_funcs; static struct syscall_metadata __used \ __syscall_meta__##sname = { \ .name = "sys_"#sname, \ + .syscall_nr = -1, /* Filled in at boot */ \ .nb_args = 0, \ .enter_event = &event_enter__##sname, \ .exit_event = &event_exit__##sname, \ diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index dc53ecb..8dc8da6 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2710,6 +2710,10 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf, mutex_lock(&trace_types_lock); if (tracer_enabled ^ val) { + + /* Only need to warn if this is used to change the state */ + WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); + if (val) { tracer_enabled = 1; if (current_trace->start) diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 8f758d0..7e62c0a 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -247,51 +247,3 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr) ctx_trace = tr; } -static void stop_sched_trace(struct trace_array *tr) -{ - tracing_stop_sched_switch_record(); -} - -static int sched_switch_trace_init(struct trace_array *tr) -{ - ctx_trace = tr; - tracing_reset_online_cpus(tr); - tracing_start_sched_switch_record(); - return 0; -} - -static void sched_switch_trace_reset(struct trace_array *tr) -{ - if (sched_ref) - stop_sched_trace(tr); -} - -static void sched_switch_trace_start(struct trace_array *tr) -{ - sched_stopped = 0; -} - -static void sched_switch_trace_stop(struct trace_array *tr) -{ - sched_stopped = 1; -} - -static struct tracer sched_switch_trace __read_mostly = -{ - .name = "sched_switch", - .init = sched_switch_trace_init, - .reset = sched_switch_trace_reset, - .start = sched_switch_trace_start, - .stop = sched_switch_trace_stop, - .wait_pipe = poll_wait_pipe, -#ifdef CONFIG_FTRACE_SELFTEST - .selftest = trace_selftest_startup_sched_switch, -#endif -}; - -__init static int init_sched_switch_trace(void) -{ - return register_tracer(&sched_switch_trace); -} -device_initcall(init_sched_switch_trace); - diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 5c9fe08..ee7b5a0 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -60,6 +60,19 @@ extern struct syscall_metadata *__stop_syscalls_metadata[]; static struct syscall_metadata **syscalls_metadata; +#ifndef ARCH_HAS_SYSCALL_MATCH_SYM_NAME +static inline bool arch_syscall_match_sym_name(const char *sym, const char *name) +{ + /* + * Only compare after the "sys" prefix. Archs that use + * syscall wrappers may have syscalls symbols aliases prefixed + * with "SyS" instead of "sys", leading to an unwanted + * mismatch. + */ + return !strcmp(sym + 3, name + 3); +} +#endif + static __init struct syscall_metadata * find_syscall_meta(unsigned long syscall) { @@ -72,14 +85,11 @@ find_syscall_meta(unsigned long syscall) stop = __stop_syscalls_metadata; kallsyms_lookup(syscall, NULL, NULL, NULL, str); + if (arch_syscall_match_sym_name(str, "sys_ni_syscall")) + return NULL; + for ( ; start < stop; start++) { - /* - * Only compare after the "sys" prefix. Archs that use - * syscall wrappers may have syscalls symbols aliases prefixed - * with "SyS" instead of "sys", leading to an unwanted - * mismatch. - */ - if ((*start)->name && !strcmp((*start)->name + 3, str + 3)) + if ((*start)->name && arch_syscall_match_sym_name(str, (*start)->name)) return *start; } return NULL; @@ -359,7 +369,7 @@ int reg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_enter) @@ -377,7 +387,7 @@ void unreg_event_syscall_enter(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_enter--; @@ -393,7 +403,7 @@ int reg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return -ENOSYS; mutex_lock(&syscall_trace_lock); if (!sys_refcount_exit) @@ -411,7 +421,7 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call) int num; num = ((struct syscall_metadata *)call->data)->syscall_nr; - if (num < 0 || num >= NR_syscalls) + if (WARN_ON_ONCE(num < 0 || num >= NR_syscalls)) return; mutex_lock(&syscall_trace_lock); sys_refcount_exit--; @@ -424,6 +434,14 @@ void unreg_event_syscall_exit(struct ftrace_event_call *call) int init_syscall_trace(struct ftrace_event_call *call) { int id; + int num; + + num = ((struct syscall_metadata *)call->data)->syscall_nr; + if (num < 0 || num >= NR_syscalls) { + pr_debug("syscall %s metadata not mapped, disabling ftrace event\n", + ((struct syscall_metadata *)call->data)->name); + return -ENOSYS; + } if (set_syscall_print_fmt(call) < 0) return -ENOMEM; @@ -438,7 +456,7 @@ int init_syscall_trace(struct ftrace_event_call *call) return id; } -unsigned long __init arch_syscall_addr(int nr) +unsigned long __init __weak arch_syscall_addr(int nr) { return (unsigned long)sys_call_table[nr]; } diff --git a/scripts/kconfig/streamline_config.pl b/scripts/kconfig/streamline_config.pl index fd81fc3..a4fe923 100644 --- a/scripts/kconfig/streamline_config.pl +++ b/scripts/kconfig/streamline_config.pl @@ -1,6 +1,6 @@ #!/usr/bin/perl -w # -# Copywrite 2005-2009 - Steven Rostedt +# Copyright 2005-2009 - Steven Rostedt # Licensed under the terms of the GNU GPL License version 2 # # It's simple enough to figure out how this works. diff --git a/tools/testing/ktest/ktest.pl b/tools/testing/ktest/ktest.pl index e1c62ee..ba7c63a 100755 --- a/tools/testing/ktest/ktest.pl +++ b/tools/testing/ktest/ktest.pl @@ -1,6 +1,6 @@ #!/usr/bin/perl -w # -# Copywrite 2010 - Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. +# Copyright 2010 - Steven Rostedt <srostedt@redhat.com>, Red Hat Inc. # Licensed under the terms of the GNU GPL License version 2 # |