From b0f56f1a63b7b968e6feeeefeace24bc8e0a4a65 Mon Sep 17 00:00:00 2001 From: Hiroshi Shimamoto Date: Thu, 1 Oct 2009 13:33:28 +0900 Subject: trace: Fix missing assignment in trace_ctxwake_* The state char variable S should be reassigned, if S == 0. We are missing the state of the task that is going to sleep for the context switch events (in the raw mode). Fortunately the problem arises with the sched_switch/wake_up tracers, not the sched trace events. The formers are legacy now. But still, that was buggy. Signed-off-by: Hiroshi Shimamoto Cc: Steven Rostedt Acked-by: Frederic Weisbecker LKML-Reference: <4AC43118.6050409@ct.jp.nec.com> Signed-off-by: Ingo Molnar --- kernel/trace/trace_output.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'kernel/trace/trace_output.c') diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index f572f44c6e1e..cda766f9f421 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -883,7 +883,7 @@ static int trace_ctxwake_raw(struct trace_iterator *iter, char S) trace_assign_type(field, iter->ent); if (!S) - task_state_char(field->prev_state); + S = task_state_char(field->prev_state); T = task_state_char(field->next_state); if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n", field->prev_pid, @@ -918,7 +918,7 @@ static int trace_ctxwake_hex(struct trace_iterator *iter, char S) trace_assign_type(field, iter->ent); if (!S) - task_state_char(field->prev_state); + S = task_state_char(field->prev_state); T = task_state_char(field->next_state); SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid); -- cgit v1.2.3 From 829b876dfc94ea8be3a47e200d06f1f217bb104f Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Sun, 27 Sep 2009 07:02:07 -0400 Subject: tracing: fix transposed numbers of lock_depth and preempt_count The lock_depth and preempt_count numbers in the latency format is transposed. Signed-off-by: Steven Rostedt --- kernel/trace/trace_output.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) (limited to 'kernel/trace/trace_output.c') diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index cda766f9f421..ed17565826b0 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -486,16 +486,18 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry) hardirq ? 'h' : softirq ? 's' : '.')) return 0; - if (entry->lock_depth < 0) - ret = trace_seq_putc(s, '.'); + if (entry->preempt_count) + ret = trace_seq_printf(s, "%x", entry->preempt_count); else - ret = trace_seq_printf(s, "%d", entry->lock_depth); + ret = trace_seq_putc(s, '.'); + if (!ret) return 0; - if (entry->preempt_count) - return trace_seq_printf(s, "%x", entry->preempt_count); - return trace_seq_putc(s, '.'); + if (entry->lock_depth < 0) + return trace_seq_putc(s, '.'); + + return trace_seq_printf(s, "%d", entry->lock_depth); } static int -- cgit v1.2.3 From 3e69533b51930a7169235db2caf703884e6e3bbb Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Fri, 23 Oct 2009 19:36:17 -0400 Subject: tracing: Fix trace_seq_printf() return value trace_seq_printf() return value is a little ambiguous. It currently returns the length of the space available in the buffer. printf usually returns the amount written. This is not adequate here, because: trace_seq_printf(s, ""); is perfectly legal, and returning 0 would indicate that it failed. We can always see the amount written by looking at the before and after values of s->len. This is not quite the same use as printf. We only care if the string was successfully written to the buffer or not. Make trace_seq_printf() return 0 if the trace oversizes the buffer's free space, 1 otherwise. Signed-off-by: Jiri Olsa Signed-off-by: Steven Rostedt Cc: Frederic Weisbecker LKML-Reference: <20091023233646.631787612@goodmis.org> Signed-off-by: Ingo Molnar --- kernel/trace/trace_output.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'kernel/trace/trace_output.c') diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index ed17565826b0..b6c12c6a1bcd 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -69,6 +69,9 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter) * @s: trace sequence descriptor * @fmt: printf format string * + * It returns 0 if the trace oversizes the buffer's free + * space, 1 otherwise. + * * The tracer may use either sequence operations or its own * copy to user routines. To simplify formating of a trace * trace_seq_printf is used to store strings into a special @@ -95,7 +98,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...) s->len += ret; - return len; + return 1; } EXPORT_SYMBOL_GPL(trace_seq_printf); -- cgit v1.2.3