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| author | zhangwei(Jovi) <jovi.zhangwei@huawei.com> | 2013-07-18 16:31:05 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-07-28 08:00:03 -0700 |
| commit | e250100beddf49178bd36886eea77b376a1e39bd (patch) | |
| tree | 6f078351f7a11ee52484d13b24086d06dce62143 /kernel | |
| parent | 9b87c4e58f2143ba9bc05ffff22d86d172e4f4ac (diff) | |
| download | lwn-e250100beddf49178bd36886eea77b376a1e39bd.tar.gz lwn-e250100beddf49178bd36886eea77b376a1e39bd.zip | |
tracing: Add ftrace_trace_stack into __trace_puts/__trace_bputs
commit 8abfb8727f4a724d31f9ccfd8013fbd16d539445 upstream.
Currently trace option stacktrace is not applicable for
trace_printk with constant string argument, the reason is
in __trace_puts/__trace_bputs ftrace_trace_stack is missing.
In contrast, when using trace_printk with non constant string
argument(will call into __trace_printk/__trace_bprintk), then
trace option stacktrace is workable, this inconstant result
will confuses users a lot.
Link: http://lkml.kernel.org/p/51E7A7C9.9040401@huawei.com
Signed-off-by: zhangwei(Jovi) <jovi.zhangwei@huawei.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/trace/trace.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 8fe92ce43f39..98a830d079b9 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -423,6 +423,9 @@ int __trace_puts(unsigned long ip, const char *str, int size) struct print_entry *entry; unsigned long irq_flags; int alloc; + int pc; + + pc = preempt_count(); if (unlikely(tracing_selftest_running || tracing_disabled)) return 0; @@ -432,7 +435,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) local_save_flags(irq_flags); buffer = global_trace.trace_buffer.buffer; event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, - irq_flags, preempt_count()); + irq_flags, pc); if (!event) return 0; @@ -449,6 +452,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) entry->buf[size] = '\0'; __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, irq_flags, 4, pc); return size; } @@ -466,6 +470,9 @@ int __trace_bputs(unsigned long ip, const char *str) struct bputs_entry *entry; unsigned long irq_flags; int size = sizeof(struct bputs_entry); + int pc; + + pc = preempt_count(); if (unlikely(tracing_selftest_running || tracing_disabled)) return 0; @@ -473,7 +480,7 @@ int __trace_bputs(unsigned long ip, const char *str) local_save_flags(irq_flags); buffer = global_trace.trace_buffer.buffer; event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, - irq_flags, preempt_count()); + irq_flags, pc); if (!event) return 0; @@ -482,6 +489,7 @@ int __trace_bputs(unsigned long ip, const char *str) entry->str = str; __buffer_unlock_commit(buffer, event); + ftrace_trace_stack(buffer, irq_flags, 4, pc); return 1; } |