The patch titled
Subject: drivers/acpi/nfit/core.c: use init_completion() in acpi_nfit_flush_probe()
has been added to the -mm tree. Its filename is
nfit-use-init_completion-in-acpi_nfit_flush_probe.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/nfit-use-init_completion-in-acpi_nfit_flush_probe.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/nfit-use-init_completion-in-acpi_nfit_flush_probe.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Boqun Feng <boqun.feng@xxxxxxxxx>
Subject: drivers/acpi/nfit/core.c: use init_completion() in acpi_nfit_flush_probe()
Patch series "completion: Reduce stack usage caused by
COMPLETION_INITIALIZER_ONSTACK()".
With LOCKDEP_CROSSRELEASE and LOCKDEP_COMPLETIONS introduced, the growth
in kernel stack usage of several functions were reported:
https://marc.info/?l=linux-kernel&m=150270063231284&w=2
The root cause of this is in COMPLETION_INITIALIZER_ONSTACK(), we use
({init_completion(&work); work})
, which will create a temporary object when returned. However this
temporary object is unnecessary. And this patch fixes it by making the
statement expression in COMPLETION_INITIALIZER_ONSTACK() return a
pointer rather than a whole structure. This will reduce the stack usage
even if !LOCKDEP.
However, such a change does make one COMPLETION_INITIALIZER_ONSTACK()
callsite invalid, so we fix this first via converting to
init_completion().
This patch (of 2):
There is no need to use COMPLETION_INITIALIZER_ONSTACK() in
acpi_nfit_flush_probe(), replace it with init_completion().
Link: http://lkml.kernel.org/r/20170823152542.5150-2-boqun.feng@xxxxxxxxx
Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Michel Lespinasse <walken@xxxxxxxxxx>
Cc: Byungchul Park <byungchul.park@xxxxxxx>
Cc: Nicholas Piggin <npiggin@xxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
drivers/acpi/nfit/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff -puN drivers/acpi/nfit/core.c~nfit-use-init_completion-in-acpi_nfit_flush_probe drivers/acpi/nfit/core.c
--- a/drivers/acpi/nfit/core.c~nfit-use-init_completion-in-acpi_nfit_flush_probe
+++ a/drivers/acpi/nfit/core.c
@@ -2884,7 +2884,7 @@ static int acpi_nfit_flush_probe(struct
* need to be interruptible while waiting.
*/
INIT_WORK_ONSTACK(&flush.work, flush_probe);
- COMPLETION_INITIALIZER_ONSTACK(flush.cmp);
+ init_completion(&flush.cmp);
queue_work(nfit_wq, &flush.work);
mutex_unlock(&acpi_desc->init_mutex);
_
Patches currently in -mm which might be from boqun.feng@xxxxxxxxx are
nfit-use-init_completion-in-acpi_nfit_flush_probe.patch
completion-avoid-unnecessary-stack-allocation-for-completion_initializer_onstack.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
