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perf: trace-event-parse: support more operators and print formats

PATCH In review David Sharp 2 participants 7 messages Mar 21, 2011 – Apr 7, 2011 perf events

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David Sharp

author
#0 lore raw

cover perf: trace-event-parse: support more operators and print formats

These patches correspond to similar patches recently applied to trace-cmd

[ Re-sending with more Cc's ]

Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>

David Sharp (2):
perf: trace-event-parse: support additional operators: '!', '~', and

    '!='

perf: trace-event-parse: support printing short fields

 tools/perf/util/trace-event-parse.c |   28 ++++++++++++++++++++++++++++
 1 files changed, 28 insertions(+), 0 deletions(-)
Signature · 1 line
1.7.3.1
author
#1 lore raw

PATCH 1/2 perf: trace-event-parse: support additional operators: '!', '~', and '!='

Add support for the unary operators '!' and '~', and support '!=' so that it is differentiated from '!'.

Signed-off-by David Sharp <[email protected]>
Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>
---
 tools/perf/util/trace-event-parse.c |   19 +++++++++++++++++++
 1 files changed, 19 insertions(+), 0 deletions(-)
tools/perf/util/trace-event-parse.c +19 -0
index 73a0222..67fe01a 100644
@@ -1107,6 +1107,9 @@ static int get_op_prio(char *op)
 {
 	if (!op[1]) {
 		switch (op[0]) {
+		case '~':
+		case '!':
+			return 4;
 		case '*':
 		case '/':
 		case '%':

@@ -1184,6 +1187,7 @@ process_op(struct event *event, struct print_arg *arg, char **tok)
 			return EVENT_ERROR;
 		}
 		switch (token[0]) {
+		case '~':
 		case '!':
 		case '+':
 		case '-':

@@ -2109,6 +2113,21 @@ static unsigned long long eval_num_arg(void *data, int size,
 		left = eval_num_arg(data, size, event, arg->op.left);
 		right = eval_num_arg(data, size, event, arg->op.right);
 		switch (arg->op.op[0]) {
+		case '!':
+			switch (arg->op.op[1]) {
+			case 0:
+				val = !right;
+				break;
+			case '=':
+				val = left != right;
+				break;
+			default:
+				die("unknown op '%s'", arg->op.op);
+			}
+			break;
+		case '~':
+			val = ~right;
+			break;
 		case '|':
 			if (arg->op.op[1])
 				val = left || right;
Signature · 1 line
1.7.3.1
author
#2 lore raw

PATCH 2/2 perf: trace-event-parse: support printing short fields

In reply to David Sharp

Handle "%hd" etc. in pretty_print()

Signed-off-by David Sharp <[email protected]>
Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>
---
 tools/perf/util/trace-event-parse.c |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)
tools/perf/util/trace-event-parse.c +9 -0
index 67fe01a..0cf4366 100644
@@ -2534,6 +2534,9 @@ static void pretty_print(void *data, int size, struct event *event)
 			case '%':
 				printf("%%");
 				break;
+			case 'h':
+				ls--;
+				goto cont_process;
 			case 'l':
 				ls++;
 				goto cont_process;

@@ -2589,6 +2592,12 @@ static void pretty_print(void *data, int size, struct event *event)
 					}
 				}
 				switch (ls) {
+				case -2:
+					printf(format, (char)val);
+					break;
+				case -1:
+					printf(format, (short)val);
+					break;
 				case 0:
 					printf(format, (int)val);
 					break;
Signature · 1 line
1.7.3.1
author
#3 lore raw
In reply to David Sharp

Hi, any feedback on these patches? I think it's important that perf and trace-cmd don't drift in the syntax they accept.

d#

Quoted 23 lines · David Sharp

These patches correspond to similar patches recently applied to trace-cmd

[ Re-sending with more Cc's ]

Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>

David Sharp (2):
 perf: trace-event-parse: support additional operators: '!', '~',  and '!='
 perf: trace-event-parse: support printing short fields

 tools/perf/util/trace-event-parse.c |   28 ++++++++++++++++++++++++++++

 1 files changed, 28 insertions(+), 0 deletions(-)

--
1.7.3.1

#4 lore raw
Quoted 4 lines · David Sharp

Hi, any feedback on these patches? I think it's important that perf and trace-cmd don't drift in the syntax they accept.

d#

Sorry, I forgot these.

Quoted 12 lines · David Sharp
Quoted 11 lines

These patches correspond to similar patches recently applied to trace-cmd

[ Re-sending with more Cc's ]

Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>
Quoted 4 lines
Quoted 4 lines

David Sharp (2):
 perf: trace-event-parse: support additional operators: '!', '~',  and '!='
 perf: trace-event-parse: support printing short fields

So we now have trace events that use these new operations? Which ones? A quick grep on "TP_printk" and "!" doesn't give me any result, probably because TP_printk is often multiline.

author
#5 lore raw
Quoted 20 lines · Frederic Weisbecker
Quoted 4 lines · David Sharp

Hi, any feedback on these patches? I think it's important that perf and trace-cmd don't drift in the syntax they accept.

d#

Sorry, I forgot these.

Quoted 12 lines · David Sharp
Quoted 11 lines

These patches correspond to similar patches recently applied to trace-cmd

[ Re-sending with more Cc's ]

Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>
Quoted 9 lines
Quoted 4 lines
Quoted 4 lines

David Sharp (2):
 perf: trace-event-parse: support additional operators: '!', '~',  and '!='
 perf: trace-event-parse: support printing short fields

So we now have trace events that use these new operations? Which ones? A quick grep on "TP_printk" and "!" doesn't give me any result, probably because TP_printk is often multiline.

We (google) have some events that use '~' and '!', and I threw in '!=' mostly because it needed to be differentiated from '!' during tokenizing.

We set the MSB of the syscall number in raw_syscalls events to indicate a compat syscall, and use '~' and '!' (and '&' and '>>') to extract the bit. eg, for sys_exit:
print fmt: "NR %ld = %ld isCompat: %d", REC->id & (~0UL>>1), REC->ret, !!(REC->id & ~(~0UL>>1))
Patches for this will be forthcoming, but, you know: time.

If our internally-added events are not sufficient reason, I think it still makes sense to support as much of the C expression syntax as reasonable. Leaving holes in the syntax mostly just causes frustration when these operators would be useful. And since they do work with the in-kernel output (which has the whole compiler to leverage), use of unsupported operators can go unnoticed for quite a while.

Thanks,
d#

#6 lore raw
Quoted 35 lines · David Sharp
Quoted 20 lines · Frederic Weisbecker
Quoted 4 lines · David Sharp

Hi, any feedback on these patches? I think it's important that perf and trace-cmd don't drift in the syntax they accept.

d#

Sorry, I forgot these.

Quoted 12 lines · David Sharp
Quoted 11 lines

These patches correspond to similar patches recently applied to trace-cmd

[ Re-sending with more Cc's ]

Cc Arnaldo Carvalho de Melo <[email protected]>
Cc Frederic Weisbecker <[email protected]>
Cc Steven Rostedt <[email protected]>
Cc Ingo Molnar <[email protected]>
Cc Stephane Eranian <[email protected]>
Quoted 9 lines
Quoted 4 lines
Quoted 4 lines

David Sharp (2):
 perf: trace-event-parse: support additional operators: '!', '~',  and '!='
 perf: trace-event-parse: support printing short fields

So we now have trace events that use these new operations? Which ones? A quick grep on "TP_printk" and "!" doesn't give me any result, probably because TP_printk is often multiline.

We (google) have some events that use '~' and '!', and I threw in '!=' mostly because it needed to be differentiated from '!' during tokenizing.

Quoted 6 lines

We set the MSB of the syscall number in raw_syscalls events to indicate a compat syscall, and use '~' and '!' (and '&' and '>>') to extract the bit. eg, for sys_exit:
print fmt: "NR %ld = %ld isCompat: %d", REC->id & (~0UL>>1), REC->ret, !!(REC->id & ~(~0UL>>1))
Patches for this will be forthcoming, but, you know: time.

Please consider the compat syscall tracing patches from Jason Baron and Ian Munsie:

http://lkml.org/lkml/2010/6/23/69

They were pretty clean IIRC. Someone just need to rebase them, clean up some last things and repost.

Quoted 7 lines

If our internally-added events are not sufficient reason, I think it still makes sense to support as much of the C expression syntax as reasonable. Leaving holes in the syntax mostly just causes frustration when these operators would be useful. And since they do work with the in-kernel output (which has the whole compiler to leverage), use of unsupported operators can go unnoticed for quite a while.

Hmm, ok.