on_each_cpu() returns as its own return value the return value of smp_call_function(). smp_call_function() in turn returns a hard coded value of zero.
Some callers to on_each_cpu() waste cycles and bloat code space by checking the return value to on_each_cpu(), probably for historical reasons. This patch set refactors callers to not test on_each_cpu() (fixed) return value and then refactors on_each_cpu to return void to avoid confusing future users. In other words, this patch aims to delete 18 source code lines while not changing any functionality :-) I tested as best as I could the x86 changes and compiled some of the others, but I don't have access to all the needed hardware for testing. Reviewers and testers welcome! CC: Michal Nazarewicz <mina86 at mina86.com> CC: David Airlie <airlied at linux.ie> CC: dri-devel at lists.freedesktop.org CC: Benjamin Herrenschmidt <benh at kernel.crashing.org> CC: Paul Mackerras <paulus at samba.org> CC: Grant Likely <grant.likely at secretlab.ca> CC: Rob Herring <rob.herring at calxeda.com> CC: linuxppc-dev at lists.ozlabs.org CC: devicetree-discuss at lists.ozlabs.org CC: Richard Henderson <rth at twiddle.net> CC: Ivan Kokshaysky <ink at jurassic.park.msu.ru> CC: Matt Turner <mattst88 at gmail.com> CC: linux-alpha at vger.kernel.org CC: Thomas Gleixner <tglx at linutronix.de> CC: Ingo Molnar <mingo at redhat.com> CC: "H. Peter Anvin" <hpa at zytor.com> CC: x86 at kernel.org CC: Tony Luck <tony.luck at intel.com> CC: Fenghua Yu <fenghua.yu at intel.com> CC: linux-ia64 at vger.kernel.org CC: Will Deacon <will.deacon at arm.com> CC: Peter Zijlstra <a.p.zijlstra at chello.nl> CC: Arnaldo Carvalho de Melo <acme at ghostprotocols.net> CC: Russell King <linux at arm.linux.org.uk> CC: linux-arm-kernel at lists.infradead.org Gilad Ben-Yossef (9): arm: avoid using on_each_cpu hard coded ret value ia64: avoid using on_each_cpu hard coded ret value x86: avoid using on_each_cpu hard coded ret value alpha: avoid using on_each_cpu hard coded ret value ppc: avoid using on_each_cpu hard coded ret value agp: avoid using on_each_cpu hard coded ret value drm: avoid using on_each_cpu hard coded ret value smp: refactor on_each_cpu to void returning func x86: refactor wbinvd_on_all_cpus to void function arch/alpha/kernel/smp.c | 7 ++----- arch/arm/kernel/perf_event.c | 2 +- arch/ia64/kernel/perfmon.c | 12 ++---------- arch/powerpc/kernel/rtas.c | 3 +-- arch/x86/include/asm/smp.h | 5 ++--- arch/x86/lib/cache-smp.c | 4 ++-- drivers/char/agp/generic.c | 3 +-- drivers/gpu/drm/drm_cache.c | 3 +-- include/linux/smp.h | 7 +++---- kernel/smp.c | 6 ++---- 10 files changed, 17 insertions(+), 35 deletions(-)
