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| author | Li Zefan <lizf@cn.fujitsu.com> | 2009-12-30 09:22:22 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-12-30 09:50:47 +0300 |
| commit | 88f7a890d74137ab0d126a5d65679cd620f1a289 (patch) | |
| tree | 93f6a908ae6eca32dd7b06be5a0cfb856c7877ac | |
| parent | 40892367bc893f3abf6f5ca8ac2ed1c98ba26a77 (diff) | |
| download | linux-88f7a890d74137ab0d126a5d65679cd620f1a289.tar.xz | |
ksym_tracer: Fix to make the tracer work
ksym tracer doesn't work:
# echo tasklist_lock:rw- > ksym_trace_filter
-bash: echo: write error: No such device
It's because we pass to perf_event_create_kernel_counter()
a cpu number which is not present.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B3AF19E.1010201@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/hw_breakpoint.c | 10 | ||||
| -rw-r--r-- | kernel/trace/trace_ksym.c | 1 |
2 files changed, 7 insertions, 4 deletions
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c index 366eedf949c0..48fb0bb6992a 100644 --- a/kernel/hw_breakpoint.c +++ b/kernel/hw_breakpoint.c @@ -40,6 +40,7 @@ #include <linux/percpu.h> #include <linux/sched.h> #include <linux/init.h> +#include <linux/cpu.h> #include <linux/smp.h> #include <linux/hw_breakpoint.h> @@ -388,7 +389,8 @@ register_wide_hw_breakpoint(struct perf_event_attr *attr, if (!cpu_events) return ERR_PTR(-ENOMEM); - for_each_possible_cpu(cpu) { + get_online_cpus(); + for_each_online_cpu(cpu) { pevent = per_cpu_ptr(cpu_events, cpu); bp = perf_event_create_kernel_counter(attr, cpu, -1, triggered); @@ -399,18 +401,20 @@ register_wide_hw_breakpoint(struct perf_event_attr *attr, goto fail; } } + put_online_cpus(); return cpu_events; fail: - for_each_possible_cpu(cpu) { + for_each_online_cpu(cpu) { pevent = per_cpu_ptr(cpu_events, cpu); if (IS_ERR(*pevent)) break; unregister_hw_breakpoint(*pevent); } + put_online_cpus(); + free_percpu(cpu_events); - /* return the error if any */ return ERR_PTR(err); } EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint); diff --git a/kernel/trace/trace_ksym.c b/kernel/trace/trace_ksym.c index faf37fa4408c..340b6ff193e0 100644 --- a/kernel/trace/trace_ksym.c +++ b/kernel/trace/trace_ksym.c @@ -197,7 +197,6 @@ int process_new_ksym_entry(char *ksymname, int op, unsigned long addr) entry->attr.bp_addr = addr; entry->attr.bp_len = HW_BREAKPOINT_LEN_4; - ret = -EAGAIN; entry->ksym_hbp = register_wide_hw_breakpoint(&entry->attr, ksym_hbp_handler); |