From 07b139c8c81b97bbe55c68daf0cbeca8b1c609ca Mon Sep 17 00:00:00 2001 From: Li Zefan Date: Mon, 21 Dec 2009 14:27:35 +0800 Subject: perf events: Remove CONFIG_EVENT_PROFILE Quoted from Ingo: | This reminds me - i think we should eliminate CONFIG_EVENT_PROFILE - | it's an unnecessary Kconfig complication. If both PERF_EVENTS and | EVENT_TRACING is enabled we should expose generic tracepoints. | | Nor is it limited to event 'profiling', so it has become a misnomer as | well. Signed-off-by: Li Zefan Cc: Frederic Weisbecker Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Paul Mackerras LKML-Reference: <4B2F1557.2050705@cn.fujitsu.com> Signed-off-by: Ingo Molnar --- kernel/trace/Makefile | 4 +++- kernel/trace/trace_events_filter.c | 4 ++-- kernel/trace/trace_kprobe.c | 14 +++++++------- kernel/trace/trace_syscalls.c | 5 ++--- 4 files changed, 14 insertions(+), 13 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile index cd9ecd89ec7..d00c6fe23f5 100644 --- a/kernel/trace/Makefile +++ b/kernel/trace/Makefile @@ -51,7 +51,9 @@ endif obj-$(CONFIG_EVENT_TRACING) += trace_events.o obj-$(CONFIG_EVENT_TRACING) += trace_export.o obj-$(CONFIG_FTRACE_SYSCALLS) += trace_syscalls.o -obj-$(CONFIG_EVENT_PROFILE) += trace_event_profile.o +ifeq ($(CONFIG_PERF_EVENTS),y) +obj-$(CONFIG_EVENT_TRACING) += trace_event_profile.o +endif obj-$(CONFIG_EVENT_TRACING) += trace_events_filter.o obj-$(CONFIG_KPROBE_EVENT) += trace_kprobe.o obj-$(CONFIG_KSYM_TRACER) += trace_ksym.o diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index 50504cb228d..74563d7e102 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -1360,7 +1360,7 @@ out_unlock: return err; } -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS void ftrace_profile_free_filter(struct perf_event *event) { @@ -1428,5 +1428,5 @@ out_unlock: return err; } -#endif /* CONFIG_EVENT_PROFILE */ +#endif /* CONFIG_PERF_EVENTS */ diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 375f81a568d..75d75dec226 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1249,7 +1249,7 @@ static int kretprobe_event_show_format(struct ftrace_event_call *call, ", REC->" FIELD_STRING_RETIP); } -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS /* Kprobe profile handler */ static __kprobes int kprobe_profile_func(struct kprobe *kp, @@ -1407,7 +1407,7 @@ static void probe_profile_disable(struct ftrace_event_call *call) disable_kprobe(&tp->rp.kp); } } -#endif /* CONFIG_EVENT_PROFILE */ +#endif /* CONFIG_PERF_EVENTS */ static __kprobes @@ -1417,10 +1417,10 @@ int kprobe_dispatcher(struct kprobe *kp, struct pt_regs *regs) if (tp->flags & TP_FLAG_TRACE) kprobe_trace_func(kp, regs); -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS if (tp->flags & TP_FLAG_PROFILE) kprobe_profile_func(kp, regs); -#endif /* CONFIG_EVENT_PROFILE */ +#endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1431,10 +1431,10 @@ int kretprobe_dispatcher(struct kretprobe_instance *ri, struct pt_regs *regs) if (tp->flags & TP_FLAG_TRACE) kretprobe_trace_func(ri, regs); -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS if (tp->flags & TP_FLAG_PROFILE) kretprobe_profile_func(ri, regs); -#endif /* CONFIG_EVENT_PROFILE */ +#endif return 0; /* We don't tweek kernel, so just return 0 */ } @@ -1463,7 +1463,7 @@ static int register_probe_event(struct trace_probe *tp) call->regfunc = probe_event_enable; call->unregfunc = probe_event_disable; -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS call->profile_enable = probe_profile_enable; call->profile_disable = probe_profile_disable; #endif diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 75289f372dd..f694f66d75b 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -421,7 +421,7 @@ int __init init_ftrace_syscalls(void) } core_initcall(init_ftrace_syscalls); -#ifdef CONFIG_EVENT_PROFILE +#ifdef CONFIG_PERF_EVENTS static DECLARE_BITMAP(enabled_prof_enter_syscalls, NR_syscalls); static DECLARE_BITMAP(enabled_prof_exit_syscalls, NR_syscalls); @@ -626,6 +626,5 @@ void prof_sysexit_disable(struct ftrace_event_call *call) mutex_unlock(&syscall_trace_lock); } -#endif - +#endif /* CONFIG_PERF_EVENTS */ -- cgit v1.2.3 From 14640106f243a3b29944d7198569090fa6546f2d Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 5 Jan 2010 17:46:48 -0500 Subject: tracing/kprobe: Drop function argument access syntax Drop function argument access syntax, because the function arguments depend on not only architecture but also compile-options and function API. And now, we have perf-probe for finding register/memory assigned to each argument. Signed-off-by: Masami Hiramatsu Cc: Frederic Weisbecker Cc: Arnaldo Carvalho de Melo Cc: systemtap Cc: DLE Cc: Frederic Weisbecker Cc: Steven Rostedt Cc: Roland McGrath Cc: Oleg Nesterov Cc: Mahesh Salgaonkar Cc: Benjamin Herrenschmidt Cc: Michael Neuling Cc: linuxppc-dev@ozlabs.org LKML-Reference: <20100105224648.19431.52309.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- Documentation/trace/kprobetrace.txt | 21 ++++++++++----------- kernel/trace/trace_kprobe.c | 18 +----------------- 2 files changed, 11 insertions(+), 28 deletions(-) (limited to 'kernel/trace') diff --git a/Documentation/trace/kprobetrace.txt b/Documentation/trace/kprobetrace.txt index c3eff6ff945..f30978e001f 100644 --- a/Documentation/trace/kprobetrace.txt +++ b/Documentation/trace/kprobetrace.txt @@ -37,15 +37,12 @@ Synopsis of kprobe_events @SYM[+|-offs] : Fetch memory at SYM +|- offs (SYM should be a data symbol) $stackN : Fetch Nth entry of stack (N >= 0) $stack : Fetch stack address. - $argN : Fetch function argument. (N >= 0)(*) - $retval : Fetch return value.(**) - +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(***) + $retval : Fetch return value.(*) + +|-offs(FETCHARG) : Fetch memory at FETCHARG +|- offs address.(**) NAME=FETCHARG: Set NAME as the argument name of FETCHARG. - (*) aN may not correct on asmlinkaged functions and at the middle of - function body. - (**) only for return probe. - (***) this is useful for fetching a field of data structures. + (*) only for return probe. + (**) this is useful for fetching a field of data structures. Per-Probe Event Filtering @@ -82,11 +79,14 @@ Usage examples To add a probe as a new event, write a new definition to kprobe_events as below. - echo p:myprobe do_sys_open dfd=$arg0 filename=$arg1 flags=$arg2 mode=$arg3 > /sys/kernel/debug/tracing/kprobe_events + echo p:myprobe do_sys_open dfd=%ax filename=%dx flags=%cx mode=+4($stack) > /sys/kernel/debug/tracing/kprobe_events This sets a kprobe on the top of do_sys_open() function with recording -1st to 4th arguments as "myprobe" event. As this example shows, users can -choose more familiar names for each arguments. +1st to 4th arguments as "myprobe" event. Note, which register/stack entry is +assigned to each function argument depends on arch-specific ABI. If you unsure +the ABI, please try to use probe subcommand of perf-tools (you can find it +under tools/perf/). +As this example shows, users can choose more familiar names for each arguments. echo r:myretprobe do_sys_open $retval >> /sys/kernel/debug/tracing/kprobe_events @@ -147,4 +147,3 @@ events, you need to enable it. returns from SYMBOL(e.g. "sys_open+0x1b/0x1d <- do_sys_open" means kernel returns from do_sys_open to sys_open+0x1b). - diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 47f54ab57b6..7ac728ded96 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -91,11 +91,6 @@ static __kprobes unsigned long fetch_memory(struct pt_regs *regs, void *addr) return retval; } -static __kprobes unsigned long fetch_argument(struct pt_regs *regs, void *num) -{ - return regs_get_argument_nth(regs, (unsigned int)((unsigned long)num)); -} - static __kprobes unsigned long fetch_retvalue(struct pt_regs *regs, void *dummy) { @@ -231,9 +226,7 @@ static int probe_arg_string(char *buf, size_t n, struct fetch_func *ff) { int ret = -EINVAL; - if (ff->func == fetch_argument) - ret = snprintf(buf, n, "$arg%lu", (unsigned long)ff->data); - else if (ff->func == fetch_register) { + if (ff->func == fetch_register) { const char *name; name = regs_query_register_name((unsigned int)((long)ff->data)); ret = snprintf(buf, n, "%%%s", name); @@ -489,14 +482,6 @@ static int parse_probe_vars(char *arg, struct fetch_func *ff, int is_return) } } else ret = -EINVAL; - } else if (strncmp(arg, "arg", 3) == 0 && isdigit(arg[3])) { - ret = strict_strtoul(arg + 3, 10, ¶m); - if (ret || param > PARAM_MAX_ARGS) - ret = -EINVAL; - else { - ff->func = fetch_argument; - ff->data = (void *)param; - } } else ret = -EINVAL; return ret; @@ -611,7 +596,6 @@ static int create_trace_probe(int argc, char **argv) * - Add kprobe: p[:[GRP/]EVENT] KSYM[+OFFS]|KADDR [FETCHARGS] * - Add kretprobe: r[:[GRP/]EVENT] KSYM[+0] [FETCHARGS] * Fetch args: - * $argN : fetch Nth of function argument. (N:0-) * $retval : fetch return value * $stack : fetch stack address * $stackN : fetch Nth of stack (N:0-) -- cgit v1.2.3 From 231e36f4d2e63dd770db80b9f5113310c2bcfcfd Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Thu, 14 Jan 2010 00:12:12 -0500 Subject: tracing/kprobe: Update kprobe tracing self test for new syntax Update kprobe tracing self test for new syntax (it supports deleting individual probes, and drops $argN support) and behavior change (new probes are disabled in default). This selftest includes the following checks: - Adding function-entry probe and return probe with arguments. - Enabling these probes. - Deleting it individually. Signed-off-by: Masami Hiramatsu Cc: systemtap Cc: DLE Cc: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <20100114051211.7814.29436.stgit@localhost6.localdomain6> Signed-off-by: Ingo Molnar --- kernel/trace/trace_kprobe.c | 55 ++++++++++++++++++++++++++++++++++++++------- 1 file changed, 47 insertions(+), 8 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 7ac728ded96..d6266cad695 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1507,28 +1507,67 @@ static int kprobe_trace_selftest_target(int a1, int a2, int a3, static __init int kprobe_trace_self_tests_init(void) { - int ret; + int ret, warn = 0; int (*target)(int, int, int, int, int, int); + struct trace_probe *tp; target = kprobe_trace_selftest_target; pr_info("Testing kprobe tracing: "); ret = command_trace_probe("p:testprobe kprobe_trace_selftest_target " - "$arg1 $arg2 $arg3 $arg4 $stack $stack0"); - if (WARN_ON_ONCE(ret)) - pr_warning("error enabling function entry\n"); + "$stack $stack0 +0($stack)"); + if (WARN_ON_ONCE(ret)) { + pr_warning("error on probing function entry.\n"); + warn++; + } else { + /* Enable trace point */ + tp = find_probe_event("testprobe", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tp == NULL)) { + pr_warning("error on getting new probe.\n"); + warn++; + } else + probe_event_enable(&tp->call); + } ret = command_trace_probe("r:testprobe2 kprobe_trace_selftest_target " "$retval"); - if (WARN_ON_ONCE(ret)) - pr_warning("error enabling function return\n"); + if (WARN_ON_ONCE(ret)) { + pr_warning("error on probing function return.\n"); + warn++; + } else { + /* Enable trace point */ + tp = find_probe_event("testprobe2", KPROBE_EVENT_SYSTEM); + if (WARN_ON_ONCE(tp == NULL)) { + pr_warning("error on getting new probe.\n"); + warn++; + } else + probe_event_enable(&tp->call); + } + + if (warn) + goto end; ret = target(1, 2, 3, 4, 5, 6); - cleanup_all_probes(); + ret = command_trace_probe("-:testprobe"); + if (WARN_ON_ONCE(ret)) { + pr_warning("error on deleting a probe.\n"); + warn++; + } + + ret = command_trace_probe("-:testprobe2"); + if (WARN_ON_ONCE(ret)) { + pr_warning("error on deleting a probe.\n"); + warn++; + } - pr_cont("OK\n"); +end: + cleanup_all_probes(); + if (warn) + pr_cont("NG: Some tests are failed. Please check them.\n"); + else + pr_cont("OK\n"); return 0; } -- cgit v1.2.3 From 430ad5a600a83956749307b13257c464c3826b55 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Thu, 28 Jan 2010 09:32:29 +0800 Subject: perf: Factorize trace events raw sample buffer operations Introduce ftrace_perf_buf_prepare() and ftrace_perf_buf_submit() to gather the common code that operates on raw events sampling buffer. This cleans up redundant code between regular trace events, syscall events and kprobe events. Changelog v1->v2: - Rename function name as per Masami and Frederic's suggestion - Add __kprobes for ftrace_perf_buf_prepare() and make ftrace_perf_buf_submit() inline as per Masami's suggestion - Export ftrace_perf_buf_prepare since modules will use it Signed-off-by: Xiao Guangrong Acked-by: Masami Hiramatsu Cc: Ingo Molnar Cc: Steven Rostedt Cc: Paul Mackerras Cc: Jason Baron Cc: Peter Zijlstra LKML-Reference: <4B60E92D.9000808@cn.fujitsu.com> Signed-off-by: Frederic Weisbecker --- include/linux/ftrace_event.h | 18 ++++++-- include/trace/ftrace.h | 48 +++------------------ kernel/trace/trace_event_profile.c | 52 ++++++++++++++++++++--- kernel/trace/trace_kprobe.c | 86 +++++--------------------------------- kernel/trace/trace_syscalls.c | 71 +++++-------------------------- 5 files changed, 88 insertions(+), 187 deletions(-) (limited to 'kernel/trace') diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h index 0a09e758c7d..cd95919d9ff 100644 --- a/include/linux/ftrace_event.h +++ b/include/linux/ftrace_event.h @@ -5,6 +5,7 @@ #include #include #include +#include struct trace_array; struct tracer; @@ -138,9 +139,6 @@ struct ftrace_event_call { #define FTRACE_MAX_PROFILE_SIZE 2048 -extern char *perf_trace_buf; -extern char *perf_trace_buf_nmi; - #define MAX_FILTER_PRED 32 #define MAX_FILTER_STR_VAL 256 /* Should handle KSYM_SYMBOL_LEN */ @@ -195,6 +193,20 @@ extern void ftrace_profile_disable(int event_id); extern int ftrace_profile_set_filter(struct perf_event *event, int event_id, char *filter_str); extern void ftrace_profile_free_filter(struct perf_event *event); +extern void * +ftrace_perf_buf_prepare(int size, unsigned short type, int *rctxp, + unsigned long *irq_flags); + +static inline void +ftrace_perf_buf_submit(void *raw_data, int size, int rctx, u64 addr, + u64 count, unsigned long irq_flags) +{ + struct trace_entry *entry = raw_data; + + perf_tp_event(entry->type, addr, count, raw_data, size); + perf_swevent_put_recursion_context(rctx); + local_irq_restore(irq_flags); +} #endif #endif /* _LINUX_FTRACE_EVENT_H */ diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h index 4a46a60c207..f2c09e4d656 100644 --- a/include/trace/ftrace.h +++ b/include/trace/ftrace.h @@ -850,22 +850,12 @@ ftrace_profile_templ_##call(struct ftrace_event_call *event_call, \ proto) \ { \ struct ftrace_data_offsets_##call __maybe_unused __data_offsets;\ - extern int perf_swevent_get_recursion_context(void); \ - extern void perf_swevent_put_recursion_context(int rctx); \ - extern void perf_tp_event(int, u64, u64, void *, int); \ struct ftrace_raw_##call *entry; \ u64 __addr = 0, __count = 1; \ unsigned long irq_flags; \ - struct trace_entry *ent; \ int __entry_size; \ int __data_size; \ - char *trace_buf; \ - char *raw_data; \ - int __cpu; \ int rctx; \ - int pc; \ - \ - pc = preempt_count(); \ \ __data_size = ftrace_get_offsets_##call(&__data_offsets, args); \ __entry_size = ALIGN(__data_size + sizeof(*entry) + sizeof(u32),\ @@ -875,42 +865,16 @@ ftrace_profile_templ_##call(struct ftrace_event_call *event_call, \ if (WARN_ONCE(__entry_size > FTRACE_MAX_PROFILE_SIZE, \ "profile buffer not large enough")) \ return; \ - \ - local_irq_save(irq_flags); \ - \ - rctx = perf_swevent_get_recursion_context(); \ - if (rctx < 0) \ - goto end_recursion; \ - \ - __cpu = smp_processor_id(); \ - \ - if (in_nmi()) \ - trace_buf = rcu_dereference(perf_trace_buf_nmi); \ - else \ - trace_buf = rcu_dereference(perf_trace_buf); \ - \ - if (!trace_buf) \ - goto end; \ - \ - raw_data = per_cpu_ptr(trace_buf, __cpu); \ - \ - *(u64 *)(&raw_data[__entry_size - sizeof(u64)]) = 0ULL; \ - entry = (struct ftrace_raw_##call *)raw_data; \ - ent = &entry->ent; \ - tracing_generic_entry_update(ent, irq_flags, pc); \ - ent->type = event_call->id; \ - \ + entry = (struct ftrace_raw_##call *)ftrace_perf_buf_prepare( \ + __entry_size, event_call->id, &rctx, &irq_flags); \ + if (!entry) \ + return; \ tstruct \ \ { assign; } \ \ - perf_tp_event(event_call->id, __addr, __count, entry, \ - __entry_size); \ - \ -end: \ - perf_swevent_put_recursion_context(rctx); \ -end_recursion: \ - local_irq_restore(irq_flags); \ + ftrace_perf_buf_submit(entry, __entry_size, rctx, __addr, \ + __count, irq_flags); \ } #undef DEFINE_EVENT diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c index 9e25573242c..f0d69300507 100644 --- a/kernel/trace/trace_event_profile.c +++ b/kernel/trace/trace_event_profile.c @@ -6,14 +6,12 @@ */ #include +#include #include "trace.h" -char *perf_trace_buf; -EXPORT_SYMBOL_GPL(perf_trace_buf); - -char *perf_trace_buf_nmi; -EXPORT_SYMBOL_GPL(perf_trace_buf_nmi); +static char *perf_trace_buf; +static char *perf_trace_buf_nmi; typedef typeof(char [FTRACE_MAX_PROFILE_SIZE]) perf_trace_t ; @@ -120,3 +118,47 @@ void ftrace_profile_disable(int event_id) } mutex_unlock(&event_mutex); } + +__kprobes void *ftrace_perf_buf_prepare(int size, unsigned short type, + int *rctxp, unsigned long *irq_flags) +{ + struct trace_entry *entry; + char *trace_buf, *raw_data; + int pc, cpu; + + pc = preempt_count(); + + /* Protect the per cpu buffer, begin the rcu read side */ + local_irq_save(*irq_flags); + + *rctxp = perf_swevent_get_recursion_context(); + if (*rctxp < 0) + goto err_recursion; + + cpu = smp_processor_id(); + + if (in_nmi()) + trace_buf = rcu_dereference(perf_trace_buf_nmi); + else + trace_buf = rcu_dereference(perf_trace_buf); + + if (!trace_buf) + goto err; + + raw_data = per_cpu_ptr(trace_buf, cpu); + + /* zero the dead bytes from align to not leak stack to user */ + *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + + entry = (struct trace_entry *)raw_data; + tracing_generic_entry_update(entry, *irq_flags, pc); + entry->type = type; + + return raw_data; +err: + perf_swevent_put_recursion_context(*rctxp); +err_recursion: + local_irq_restore(*irq_flags); + return NULL; +} +EXPORT_SYMBOL_GPL(ftrace_perf_buf_prepare); diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index d6266cad695..2e28ee36646 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1243,14 +1243,10 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp, struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); struct ftrace_event_call *call = &tp->call; struct kprobe_trace_entry *entry; - struct trace_entry *ent; - int size, __size, i, pc, __cpu; + int size, __size, i; unsigned long irq_flags; - char *trace_buf; - char *raw_data; int rctx; - pc = preempt_count(); __size = SIZEOF_KPROBE_TRACE_ENTRY(tp->nr_args); size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1258,45 +1254,16 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp, "profile buffer not large enough")) return 0; - /* - * Protect the non nmi buffer - * This also protects the rcu read side - */ - local_irq_save(irq_flags); - - rctx = perf_swevent_get_recursion_context(); - if (rctx < 0) - goto end_recursion; - - __cpu = smp_processor_id(); - - if (in_nmi()) - trace_buf = rcu_dereference(perf_trace_buf_nmi); - else - trace_buf = rcu_dereference(perf_trace_buf); - - if (!trace_buf) - goto end; - - raw_data = per_cpu_ptr(trace_buf, __cpu); - - /* Zero dead bytes from alignment to avoid buffer leak to userspace */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; - entry = (struct kprobe_trace_entry *)raw_data; - ent = &entry->ent; + entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags); + if (!entry) + return 0; - tracing_generic_entry_update(ent, irq_flags, pc); - ent->type = call->id; entry->nargs = tp->nr_args; entry->ip = (unsigned long)kp->addr; for (i = 0; i < tp->nr_args; i++) entry->args[i] = call_fetch(&tp->args[i].fetch, regs); - perf_tp_event(call->id, entry->ip, 1, entry, size); -end: - perf_swevent_put_recursion_context(rctx); -end_recursion: - local_irq_restore(irq_flags); + ftrace_perf_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags); return 0; } @@ -1308,14 +1275,10 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); struct ftrace_event_call *call = &tp->call; struct kretprobe_trace_entry *entry; - struct trace_entry *ent; - int size, __size, i, pc, __cpu; + int size, __size, i; unsigned long irq_flags; - char *trace_buf; - char *raw_data; int rctx; - pc = preempt_count(); __size = SIZEOF_KRETPROBE_TRACE_ENTRY(tp->nr_args); size = ALIGN(__size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); @@ -1323,46 +1286,17 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, "profile buffer not large enough")) return 0; - /* - * Protect the non nmi buffer - * This also protects the rcu read side - */ - local_irq_save(irq_flags); - - rctx = perf_swevent_get_recursion_context(); - if (rctx < 0) - goto end_recursion; - - __cpu = smp_processor_id(); - - if (in_nmi()) - trace_buf = rcu_dereference(perf_trace_buf_nmi); - else - trace_buf = rcu_dereference(perf_trace_buf); - - if (!trace_buf) - goto end; - - raw_data = per_cpu_ptr(trace_buf, __cpu); - - /* Zero dead bytes from alignment to avoid buffer leak to userspace */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; - entry = (struct kretprobe_trace_entry *)raw_data; - ent = &entry->ent; + entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags); + if (!entry) + return 0; - tracing_generic_entry_update(ent, irq_flags, pc); - ent->type = call->id; entry->nargs = tp->nr_args; entry->func = (unsigned long)tp->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; for (i = 0; i < tp->nr_args; i++) entry->args[i] = call_fetch(&tp->args[i].fetch, regs); - perf_tp_event(call->id, entry->ret_ip, 1, entry, size); -end: - perf_swevent_put_recursion_context(rctx); -end_recursion: - local_irq_restore(irq_flags); + ftrace_perf_buf_submit(entry, size, rctx, entry->ret_ip, 1, irq_flags); return 0; } diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index f694f66d75b..4e332b9e449 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -433,12 +433,9 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) struct syscall_metadata *sys_data; struct syscall_trace_enter *rec; unsigned long flags; - char *trace_buf; - char *raw_data; int syscall_nr; int rctx; int size; - int cpu; syscall_nr = syscall_get_nr(current, regs); if (!test_bit(syscall_nr, enabled_prof_enter_syscalls)) @@ -457,37 +454,15 @@ static void prof_syscall_enter(struct pt_regs *regs, long id) "profile buffer not large enough")) return; - /* Protect the per cpu buffer, begin the rcu read side */ - local_irq_save(flags); - - rctx = perf_swevent_get_recursion_context(); - if (rctx < 0) - goto end_recursion; - - cpu = smp_processor_id(); - - trace_buf = rcu_dereference(perf_trace_buf); - - if (!trace_buf) - goto end; - - raw_data = per_cpu_ptr(trace_buf, cpu); - - /* zero the dead bytes from align to not leak stack to user */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; + rec = (struct syscall_trace_enter *)ftrace_perf_buf_prepare(size, + sys_data->enter_event->id, &rctx, &flags); + if (!rec) + return; - rec = (struct syscall_trace_enter *) raw_data; - tracing_generic_entry_update(&rec->ent, 0, 0); - rec->ent.type = sys_data->enter_event->id; rec->nr = syscall_nr; syscall_get_arguments(current, regs, 0, sys_data->nb_args, (unsigned long *)&rec->args); - perf_tp_event(sys_data->enter_event->id, 0, 1, rec, size); - -end: - perf_swevent_put_recursion_context(rctx); -end_recursion: - local_irq_restore(flags); + ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags); } int prof_sysenter_enable(struct ftrace_event_call *call) @@ -531,11 +506,8 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) struct syscall_trace_exit *rec; unsigned long flags; int syscall_nr; - char *trace_buf; - char *raw_data; int rctx; int size; - int cpu; syscall_nr = syscall_get_nr(current, regs); if (!test_bit(syscall_nr, enabled_prof_exit_syscalls)) @@ -557,38 +529,15 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret) "exit event has grown above profile buffer size")) return; - /* Protect the per cpu buffer, begin the rcu read side */ - local_irq_save(flags); - - rctx = perf_swevent_get_recursion_context(); - if (rctx < 0) - goto end_recursion; - - cpu = smp_processor_id(); - - trace_buf = rcu_dereference(perf_trace_buf); - - if (!trace_buf) - goto end; - - raw_data = per_cpu_ptr(trace_buf, cpu); - - /* zero the dead bytes from align to not leak stack to user */ - *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL; - - rec = (struct syscall_trace_exit *)raw_data; + rec = (struct syscall_trace_exit *)ftrace_perf_buf_prepare(size, + sys_data->exit_event->id, &rctx, &flags); + if (!rec) + return; - tracing_generic_entry_update(&rec->ent, 0, 0); - rec->ent.type = sys_data->exit_event->id; rec->nr = syscall_nr; rec->ret = syscall_get_return_value(current, regs); - perf_tp_event(sys_data->exit_event->id, 0, 1, rec, size); - -end: - perf_swevent_put_recursion_context(rctx); -end_recursion: - local_irq_restore(flags); + ftrace_perf_buf_submit(rec, size, rctx, 0, 1, flags); } int prof_sysexit_enable(struct ftrace_event_call *call) -- cgit v1.2.3 From 1e12a4a7a3a78bc9c3aaf3486dde3b8ab1cdf465 Mon Sep 17 00:00:00 2001 From: Xiao Guangrong Date: Thu, 28 Jan 2010 09:34:27 +0800 Subject: tracing/kprobe: Cleanup unused return value of tracing functions The return values of the kprobe's tracing functions are meaningless, lets remove these. Signed-off-by: Xiao Guangrong Acked-by: Masami Hiramatsu Cc: Steven Rostedt Cc: Ingo Molnar Cc: Paul Mackerras Cc: Jason Baron Cc: Peter Zijlstra LKML-Reference: <4B60E9A3.2040505@cn.fujitsu.com> [fweisbec@gmail: whitespace fixes, drop useless void returns in end of functions] Signed-off-by: Frederic Weisbecker --- kernel/trace/trace_kprobe.c | 27 ++++++++++----------------- 1 file changed, 10 insertions(+), 17 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 2e28ee36646..6178abf3637 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -942,7 +942,7 @@ static const struct file_operations kprobe_profile_ops = { }; /* Kprobe handler */ -static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) +static __kprobes void kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) { struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); struct kprobe_trace_entry *entry; @@ -962,7 +962,7 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) event = trace_current_buffer_lock_reserve(&buffer, call->id, size, irq_flags, pc); if (!event) - return 0; + return; entry = ring_buffer_event_data(event); entry->nargs = tp->nr_args; @@ -972,11 +972,10 @@ static __kprobes int kprobe_trace_func(struct kprobe *kp, struct pt_regs *regs) if (!filter_current_check_discard(buffer, call, entry, event)) trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); - return 0; } /* Kretprobe handler */ -static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, +static __kprobes void kretprobe_trace_func(struct kretprobe_instance *ri, struct pt_regs *regs) { struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); @@ -995,7 +994,7 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, event = trace_current_buffer_lock_reserve(&buffer, call->id, size, irq_flags, pc); if (!event) - return 0; + return; entry = ring_buffer_event_data(event); entry->nargs = tp->nr_args; @@ -1006,8 +1005,6 @@ static __kprobes int kretprobe_trace_func(struct kretprobe_instance *ri, if (!filter_current_check_discard(buffer, call, entry, event)) trace_nowake_buffer_unlock_commit(buffer, event, irq_flags, pc); - - return 0; } /* Event entry printers */ @@ -1237,7 +1234,7 @@ static int kretprobe_event_show_format(struct ftrace_event_call *call, #ifdef CONFIG_PERF_EVENTS /* Kprobe profile handler */ -static __kprobes int kprobe_profile_func(struct kprobe *kp, +static __kprobes void kprobe_profile_func(struct kprobe *kp, struct pt_regs *regs) { struct trace_probe *tp = container_of(kp, struct trace_probe, rp.kp); @@ -1252,11 +1249,11 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp, size -= sizeof(u32); if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, "profile buffer not large enough")) - return 0; + return; entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags); if (!entry) - return 0; + return; entry->nargs = tp->nr_args; entry->ip = (unsigned long)kp->addr; @@ -1264,12 +1261,10 @@ static __kprobes int kprobe_profile_func(struct kprobe *kp, entry->args[i] = call_fetch(&tp->args[i].fetch, regs); ftrace_perf_buf_submit(entry, size, rctx, entry->ip, 1, irq_flags); - - return 0; } /* Kretprobe profile handler */ -static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, +static __kprobes void kretprobe_profile_func(struct kretprobe_instance *ri, struct pt_regs *regs) { struct trace_probe *tp = container_of(ri->rp, struct trace_probe, rp); @@ -1284,11 +1279,11 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, size -= sizeof(u32); if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE, "profile buffer not large enough")) - return 0; + return; entry = ftrace_perf_buf_prepare(size, call->id, &rctx, &irq_flags); if (!entry) - return 0; + return; entry->nargs = tp->nr_args; entry->func = (unsigned long)tp->rp.kp.addr; @@ -1297,8 +1292,6 @@ static __kprobes int kretprobe_profile_func(struct kretprobe_instance *ri, entry->args[i] = call_fetch(&tp->args[i].fetch, regs); ftrace_perf_buf_submit(entry, size, rctx, entry->ret_ip, 1, irq_flags); - - return 0; } static int probe_profile_enable(struct ftrace_event_call *call) -- cgit v1.2.3 From 2cfa19780d61740f65790c5bae363b759d7c96fa Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 2 Feb 2010 16:49:11 -0500 Subject: ftrace/alternatives: Introducing *_text_reserved functions Introducing *_text_reserved functions for checking the text address range is partially reserved or not. This patch provides checking routines for x86 smp alternatives and dynamic ftrace. Since both functions modify fixed pieces of kernel text, they should reserve and protect those from other dynamic text modifier, like kprobes. This will also be extended when introducing other subsystems which modify fixed pieces of kernel text. Dynamic text modifiers should avoid those. Signed-off-by: Masami Hiramatsu Cc: systemtap Cc: DLE Cc: Steven Rostedt Cc: przemyslaw@pawelczyk.it Cc: Frederic Weisbecker Cc: Ananth N Mavinakayanahalli Cc: Jim Keniston Cc: Mathieu Desnoyers Cc: Jason Baron LKML-Reference: <20100202214911.4694.16587.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/alternative.h | 5 +++++ arch/x86/kernel/alternative.c | 16 ++++++++++++++++ include/linux/ftrace.h | 6 ++++++ kernel/trace/ftrace.c | 15 +++++++++++++++ 4 files changed, 42 insertions(+) (limited to 'kernel/trace') diff --git a/arch/x86/include/asm/alternative.h b/arch/x86/include/asm/alternative.h index 69b74a7b877..ac80b7d7001 100644 --- a/arch/x86/include/asm/alternative.h +++ b/arch/x86/include/asm/alternative.h @@ -65,12 +65,17 @@ extern void alternatives_smp_module_add(struct module *mod, char *name, void *text, void *text_end); extern void alternatives_smp_module_del(struct module *mod); extern void alternatives_smp_switch(int smp); +extern int alternatives_text_reserved(void *start, void *end); #else static inline void alternatives_smp_module_add(struct module *mod, char *name, void *locks, void *locks_end, void *text, void *text_end) {} static inline void alternatives_smp_module_del(struct module *mod) {} static inline void alternatives_smp_switch(int smp) {} +static inline int alternatives_text_reserved(void *start, void *end) +{ + return 0; +} #endif /* CONFIG_SMP */ /* alternative assembly primitive: */ diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c index de7353c0ce9..3c13284ff86 100644 --- a/arch/x86/kernel/alternative.c +++ b/arch/x86/kernel/alternative.c @@ -390,6 +390,22 @@ void alternatives_smp_switch(int smp) mutex_unlock(&smp_alt); } +/* Return 1 if the address range is reserved for smp-alternatives */ +int alternatives_text_reserved(void *start, void *end) +{ + struct smp_alt_module *mod; + u8 **ptr; + + list_for_each_entry(mod, &smp_alt_modules, next) { + if (mod->text > end || mod->text_end < start) + continue; + for (ptr = mod->locks; ptr < mod->locks_end; ptr++) + if (start <= *ptr && end >= *ptr) + return 1; + } + + return 0; +} #endif #ifdef CONFIG_PARAVIRT diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 0b4f97d24d7..9d127efed43 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -134,6 +134,8 @@ extern void unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops); extern void unregister_ftrace_function_probe_all(char *glob); +extern int ftrace_text_reserved(void *start, void *end); + enum { FTRACE_FL_FREE = (1 << 0), FTRACE_FL_FAILED = (1 << 1), @@ -250,6 +252,10 @@ static inline int unregister_ftrace_command(char *cmd_name) { return -EINVAL; } +static inline int ftrace_text_reserved(void *start, void *end) +{ + return 0; +} #endif /* CONFIG_DYNAMIC_FTRACE */ /* totally disable ftrace - can not re-enable after this */ diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 1e6640f8045..3d90661a5f4 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1025,6 +1025,21 @@ static void ftrace_bug(int failed, unsigned long ip) } +/* Return 1 if the address range is reserved for ftrace */ +int ftrace_text_reserved(void *start, void *end) +{ + struct dyn_ftrace *rec; + struct ftrace_page *pg; + + do_for_each_ftrace_rec(pg, rec) { + if (rec->ip <= (unsigned long)end && + rec->ip + MCOUNT_INSN_SIZE > (unsigned long)start) + return 1; + } while_for_each_ftrace_rec(); + return 0; +} + + static int __ftrace_replace_code(struct dyn_ftrace *rec, int enable) { -- cgit v1.2.3 From f24bb999d2b9f2950e5cac5b69bffedf73c24ea4 Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Tue, 2 Feb 2010 16:49:25 -0500 Subject: ftrace: Remove record freezing Remove record freezing. Because kprobes never puts probe on ftrace's mcount call anymore, it doesn't need ftrace to check whether kprobes on it. Signed-off-by: Masami Hiramatsu Cc: systemtap Cc: DLE Cc: Steven Rostedt Cc: przemyslaw@pawelczyk.it Cc: Frederic Weisbecker LKML-Reference: <20100202214925.4694.73469.stgit@dhcp-100-2-132.bos.redhat.com> Signed-off-by: Ingo Molnar --- include/linux/ftrace.h | 1 - kernel/trace/ftrace.c | 39 --------------------------------------- 2 files changed, 40 deletions(-) (limited to 'kernel/trace') diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 9d127efed43..eb054ae9560 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -143,7 +143,6 @@ enum { FTRACE_FL_ENABLED = (1 << 3), FTRACE_FL_NOTRACE = (1 << 4), FTRACE_FL_CONVERTED = (1 << 5), - FTRACE_FL_FROZEN = (1 << 6), }; struct dyn_ftrace { diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 3d90661a5f4..1904797f4a8 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -22,7 +22,6 @@ #include #include #include -#include #include #include #include @@ -898,36 +897,6 @@ static struct dyn_ftrace *ftrace_free_records; } \ } -#ifdef CONFIG_KPROBES - -static int frozen_record_count; - -static inline void freeze_record(struct dyn_ftrace *rec) -{ - if (!(rec->flags & FTRACE_FL_FROZEN)) { - rec->flags |= FTRACE_FL_FROZEN; - frozen_record_count++; - } -} - -static inline void unfreeze_record(struct dyn_ftrace *rec) -{ - if (rec->flags & FTRACE_FL_FROZEN) { - rec->flags &= ~FTRACE_FL_FROZEN; - frozen_record_count--; - } -} - -static inline int record_frozen(struct dyn_ftrace *rec) -{ - return rec->flags & FTRACE_FL_FROZEN; -} -#else -# define freeze_record(rec) ({ 0; }) -# define unfreeze_record(rec) ({ 0; }) -# define record_frozen(rec) ({ 0; }) -#endif /* CONFIG_KPROBES */ - static void ftrace_free_rec(struct dyn_ftrace *rec) { rec->freelist = ftrace_free_records; @@ -1091,14 +1060,6 @@ static void ftrace_replace_code(int enable) !(rec->flags & FTRACE_FL_CONVERTED)) continue; - /* ignore updates to this record's mcount site */ - if (get_kprobe((void *)rec->ip)) { - freeze_record(rec); - continue; - } else { - unfreeze_record(rec); - } - failed = __ftrace_replace_code(rec, enable); if (failed) { rec->flags |= FTRACE_FL_FAILED; -- cgit v1.2.3