[PATCH 0/1] perf build: fix "argument list too long" in second location

[PATCH 0/1] perf build: fix "argument list too long" in second location

[Markus Mayer]

Hi all,

My apologies for not catching this one sooner. Using xargs in the actual
build recipe worked, but it turns out echoing $^ in quiet_cmd_rm also
offends the shell. Somehow, it didn't show up during my tests before
submitting the previous fix[1] for this issue or I would have addressed
both together.

But then it did start to show up. Like this:

  GEN     linux/tools/perf/pmu-events/arch/arm64/arm/neoverse-v3/extra-metricgroups.json
  TEST    linux/tools/perf/pmu-events/metric_test.log
make[5]: /bin/sh: Argument list too long
make[5]: *** [pmu-events/Build:220: prune_orphans] Error 127

This was a bit of a head-scratcher before I realized that this came from
    quiet_cmd_rm  = RM      $^
and that no attempt of putting quotes around $^ would help.

With change proposed here, it'll look like this instead:

  GEN     linux/tools/perf/pmu-events/arch/arm64/arm/neoverse-v3/extra-metricgroups.json
  TEST    linux/tools/perf/pmu-events/metric_test.log
  RM      ...634 orphan file(s)...
  LD      linux/tools/perf/util/perf-util-in.o

This is probably a good thing, regardless of the shell complaining,
since listing 634 files in a so-called "quiet" message is probably not
very fitting.

I don't know why my build has 634 orphans every single time it runs
(straight-up cross-build on x86_64 for ARM64) or if that is a lot. I do
get the impression that it is probably rather unusual. Not really doing
anything special, though.

Also, the build machines are running Ubuntu 24.04. As such, /bin/sh is
provided by /bin/dash. This may also factor into why I might be seeing
this issue while others may not.

Again, sorry for the churn. Hopefully this is it now on the orphan front.

Regards,
-Markus

[1] https://lore.kernel.org/linux-perf-users/20260303211503.165337-1-mmayer@broadcom.com/

Markus Mayer (1):
  perf build: fix "argument list too long" in second location

 tools/perf/pmu-events/Build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

-- 
2.53.0

[PATCH 1/1] perf build: fix "argument list too long" in second location

[Markus Mayer]

Turns out that displaying "RM $^" via quiet_cmd_rm can also upset the
shell and cause it to display "argument list too long".

Trying to quote $^ doesn't help.

In the end, *not* displaying the (potentially long) list of files is
probably the right thing to do for a "quiet" message, anyway. Instead,
let's display a count of how many files were removed. There is always
V=1 if more detail is required.

  TEST    linux/tools/perf/pmu-events/metric_test.log
  RM      ...634 orphan file(s)...
  LD      linux/tools/perf/util/perf-util-in.o

Also move the comment regarding xargs before the rule, so it doesn't
show up in the build output.

Signed-off-by: Markus Mayer <mmayer@broadcom.com>
---
 tools/perf/pmu-events/Build | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/pmu-events/Build b/tools/perf/pmu-events/Build
index dc5f94862a3b..dc1df2d57ddc 100644
--- a/tools/perf/pmu-events/Build
+++ b/tools/perf/pmu-events/Build
@@ -211,10 +211,10 @@ ifneq ($(strip $(ORPHAN_FILES)),)
 
 # Message for $(call echo-cmd,rm). Generally cleaning files isn't part
 # of a build step.
-quiet_cmd_rm  = RM      $^
+quiet_cmd_rm = RM      ...$(words $^) orphan file(s)...
 
+# The list of files can be long. Use xargs to prevent issues.
 prune_orphans: $(ORPHAN_FILES)
-	# The list of files can be long. Use xargs to prevent issues.
 	$(Q)$(call echo-cmd,rm)echo "$^" | xargs rm -f
 
 JEVENTS_DEPS += prune_orphans
-- 
2.53.0

Re: [PATCH 1/1] perf build: fix "argument list too long" in second location

[James Clark]

On 09/04/2026 11:14 pm, Markus Mayer wrote:
> Turns out that displaying "RM $^" via quiet_cmd_rm can also upset the
> shell and cause it to display "argument list too long".
> 
> Trying to quote $^ doesn't help.
> 
> In the end, *not* displaying the (potentially long) list of files is
> probably the right thing to do for a "quiet" message, anyway. Instead,
> let's display a count of how many files were removed. There is always
> V=1 if more detail is required.
> 
>    TEST    linux/tools/perf/pmu-events/metric_test.log
>    RM      ...634 orphan file(s)...
>    LD      linux/tools/perf/util/perf-util-in.o
> 
> Also move the comment regarding xargs before the rule, so it doesn't
> show up in the build output.
> 

I'm assuming this is just a cosmetic issue so it doesn't need a fixes 
tag? And "upsetting the shell" doesn't cause a build failure?

Otherwise looks good to me.

Reviewed-by: James Clark <james.clark@linaro.org>

> Signed-off-by: Markus Mayer <mmayer@broadcom.com>
> ---
>   tools/perf/pmu-events/Build | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/pmu-events/Build b/tools/perf/pmu-events/Build
> index dc5f94862a3b..dc1df2d57ddc 100644
> --- a/tools/perf/pmu-events/Build
> +++ b/tools/perf/pmu-events/Build
> @@ -211,10 +211,10 @@ ifneq ($(strip $(ORPHAN_FILES)),)
>   
>   # Message for $(call echo-cmd,rm). Generally cleaning files isn't part
>   # of a build step.
> -quiet_cmd_rm  = RM      $^
> +quiet_cmd_rm = RM      ...$(words $^) orphan file(s)...
>   
> +# The list of files can be long. Use xargs to prevent issues.
>   prune_orphans: $(ORPHAN_FILES)
> -	# The list of files can be long. Use xargs to prevent issues.
>   	$(Q)$(call echo-cmd,rm)echo "$^" | xargs rm -f
>   
>   JEVENTS_DEPS += prune_orphans