Re: [GIT PULL] tracing: Updates for 6.6
From: Valentin Schneider
Date: Fri Sep 01 2023 - 05:21:52 EST
Hi,
On 31/08/23 11:56, Steven Rostedt wrote:
> Linus,
>
> [ Note, there's a minor conflict which should be fixed by:
> mutex_lock(&trace_types_lock);
> - if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) {
> + if (unlikely(tr->current_trace != iter->trace))
> + /* Close iter->trace before switching to the new current tracer */
> + if (iter->trace->close)
> + iter->trace->close(iter);
> - *iter->trace = *tr->current_trace;
> + iter->trace = tr->current_trace;
> + /* Reopen the new current tracer */
> + if (iter->trace->open)
> + iter->trace->open(iter);
> + }
> mutex_unlock(&trace_types_lock);
> ]
>
> Tracing updates for 6.6:
>
> User visible changes:
>
> - Added a way to easier filter with cpumasks:
> # echo 'cpumask & CPUS{17-42}' > /sys/kernel/tracing/events/ipi_send_cpumask/filter
>
It looks like the patches included are from v2 of [1], which still had some
(small) issues to fix. I have addressed these in [2], but I haven't sent
this out yet as I'm still working on the context_tracking/vmalloc part of
the series.
I'm happy to send just the tracing bits, if that helps - or just send the
deltas as separate fixes, whatever makes it easier.
Apologies for not bringing this up when the patches were picked up in [3],
I've only just come back from PTO/moving abroad and have started catching
up.
[1]: https://lore.kernel.org/all/20230720163056.2564824-1-vschneid@xxxxxxxxxx/
[2]: https://gitlab.com/vschneid/linux/-/commits/redhat/isolirq/defer/v3-wip
[3]: https://lore.kernel.org/all/20230824021812.938245293@xxxxxxxxxxx/
For reference, the git range-diff between the patches in
tracing/trace/for-next and those in my v3 is appended below (pure changelog
diffs removed)
---
2: 39f7c41c908bc ! 2: e58d79bd79da2 tracing/filters: Enable filtering a cpumask field by another cpumask
## include/linux/trace_events.h ##
@@ include/linux/trace_events.h: enum {
@@ kernel/trace/trace_events_filter.c: static void filter_free_subsystem_filters(st
+ return FILTER_DYN_STRING;
+ if (strstr(type, "cpumask_t"))
+ return FILTER_CPUMASK;
-+ }
++ }
if (strstr(type, "__rel_loc") && strstr(type, "char"))
return FILTER_RDYN_STRING;
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void
+ maskstart = i;
+
+ /* Walk the cpulist until closing } */
-+ for (; str[i] && str[i] != '}'; i++);
++ for (; str[i] && str[i] != '}'; i++)
++ ;
++
+ if (str[i] != '}') {
+ parse_error(pe, FILT_ERR_MISSING_BRACE_CLOSE, pos + i);
+ goto err_free;
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void
+
+ /* Copy the cpulist between { and } */
+ tmp = kmalloc((i - maskstart) + 1, GFP_KERNEL);
-+ strscpy(tmp, str + maskstart, (i - maskstart) + 1);
++ if (!tmp)
++ goto err_mem;
+
++ strscpy(tmp, str + maskstart, (i - maskstart) + 1);
+ pred->mask = kzalloc(cpumask_size(), GFP_KERNEL);
-+ if (!pred->mask)
++ if (!pred->mask) {
++ kfree(tmp);
+ goto err_mem;
++ }
+
+ /* Now parse it */
+ if (cpulist_parse(tmp, pred->mask)) {
++ kfree(tmp);
+ parse_error(pe, FILT_ERR_INVALID_CPULIST, pos + i);
+ goto err_free;
+ }
++ kfree(tmp);
+
+ /* Move along */
+ i++;
5: fe4fa4ec9b464 ! 5: 03eefdab555b2 tracing/filters: Optimise cpumask vs cpumask filtering when user mask is a single CPU
## kernel/trace/trace_events_filter.c ##
@@ kernel/trace/trace_events_filter.c: enum filter_pred_fn {
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void
+ if (single && field->filter_type == FILTER_CPUMASK) {
+ pred->val = cpumask_first(pred->mask);
+ kfree(pred->mask);
++ pred->mask = NULL;
+ }
+
if (field->filter_type == FILTER_CPUMASK) {
6: ca77dd8ce4658 ! 6: f75aee048ce5a tracing/filters: Optimise scalar vs cpumask filtering when the user mask is a single CPU
@@ Commit message
## kernel/trace/trace_events_filter.c ##
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void *data,
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void
+ if (single && field->filter_type != FILTER_CPU) {
pred->val = cpumask_first(pred->mask);
kfree(pred->mask);
- }
+ pred->mask = NULL;
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void *data,
FILTER_PRED_FN_CPUMASK;
} else if (field->filter_type == FILTER_CPU) {
pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;
+ } else if (single) {
-+ pred->op = pred->op == OP_BAND ? OP_EQ : pred->op;
++ if (pred->op == OP_BAND)
++ pred->op = OP_EQ;
++
+ pred->fn_num = select_comparison_fn(pred->op, field->size, false);
+ if (pred->op == OP_NE)
+ pred->not = 1;
7: 1cffbe6c62f10 ! 7: 6a78ed47b0b06 tracing/filters: Optimise CPU vs cpumask filtering when the user mask is a single CPU
## kernel/trace/trace_events_filter.c ##
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void *data,
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void
+ if (single) {
pred->val = cpumask_first(pred->mask);
kfree(pred->mask);
- }
+ pred->mask = NULL;
@@ kernel/trace/trace_events_filter.c: static int parse_pred(const char *str, void *data,
FILTER_PRED_FN_CPUMASK_CPU :
FILTER_PRED_FN_CPUMASK;
} else if (field->filter_type == FILTER_CPU) {
- pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;
+ if (single) {
-+ pred->op = pred->op == OP_BAND ? OP_EQ : pred->op;
++ if (pred->op == OP_BAND)
++ pred->op = OP_EQ;
++
+ pred->fn_num = FILTER_PRED_FN_CPU;
+ } else {
+ pred->fn_num = FILTER_PRED_FN_CPU_CPUMASK;
+ }
} else if (single) {
- pred->op = pred->op == OP_BAND ? OP_EQ : pred->op;
- pred->fn_num = select_comparison_fn(pred->op, field->size, false);
+ if (pred->op == OP_BAND)
+ pred->op = OP_EQ;