| Message ID | 20240502233017.419365-1-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | clocksource/drivers/arm_arch_timer: Mark validate_timer_rate() init | expand |
On 5/3/2024 5:00 AM, Stephen Boyd wrote: > Add the __init marking to validate_timer_rate() so that it gets > discarded after init. > > $ ./scripts/bloat-o-meter vmlinux.before vmlinux.after > add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) > Function old new delta > arch_timer_register 1724 1716 -8 Have not used this tool bloat-o-meter Just a question, why is it showing arch_timer_register is shrunk ? -Mukesh
Quoting Mukesh Ojha (2024-05-03 04:27:52) > > > On 5/3/2024 5:00 AM, Stephen Boyd wrote: > > Add the __init marking to validate_timer_rate() so that it gets > > discarded after init. > > > > $ ./scripts/bloat-o-meter vmlinux.before vmlinux.after > > add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) > > Function old new delta > > arch_timer_register 1724 1716 -8 > > Have not used this tool bloat-o-meter > Just a question, why is it showing arch_timer_register is shrunk ? Hmm good question. There shouldn't be any difference if it gets inlined. It's an allmodconfig build. It looks like that causes noise in the build so it isn't stable. :( I diffed the objdump and the function is missing this ror and nop instruction. But then I built it again, and it became more different. If I build an allnoconfig it has zero difference. Before: ffff800083021ed4: 974ba12d bl ffff80008030a388 <free_percpu_irq> ffff800083021ed8: 93d3f273 ror x19, x19, #60 ffff800083021edc: d503201f nop ffff800083021ee0: d29858e0 mov x0, #0xc2c7 // #49863 ffff800083021ee4: 910102b6 add x22, x21, #0x40 ffff800083021ee8: f2aeea20 movk x0, #0x7751, lsl #16 ffff800083021eec: f2ce7680 movk x0, #0x73b4, lsl #32 ffff800083021ef0: f2f09e20 movk x0, #0x84f1, lsl #48 ffff800083021ef4: ca000273 eor x19, x19, x0 ffff800083021ef8: 97527f02 bl ffff8000804c1b00 <__sanitizer_cov_trace_pc> After: ffff800083021ed4: 974ba12d bl ffff80008030a388 <free_percpu_irq> ffff800083021ed8: d29f9f00 mov x0, #0xfcf8 // #64760 ffff800083021edc: 910102b6 add x22, x21, #0x40 ffff800083021ee0: f2b03940 movk x0, #0x81ca, lsl #16 ffff800083021ee4: f2d5e700 movk x0, #0xaf38, lsl #32 ffff800083021ee8: f2ee1340 movk x0, #0x709a, lsl #48 ffff800083021eec: ca000273 eor x19, x19, x0 ffff800083021ef0: 97527f04 bl ffff8000804c1b00 <__sanitizer_cov_trace_pc> Maybe kcov is making things different?
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 8d4a52056684..9c4a4af25d2c 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -1045,7 +1045,7 @@ static int arch_timer_starting_cpu(unsigned int cpu) return 0; } -static int validate_timer_rate(void) +static int __init validate_timer_rate(void) { if (!arch_timer_rate) return -EINVAL;
Add the __init marking to validate_timer_rate() so that it gets discarded after init. $ ./scripts/bloat-o-meter vmlinux.before vmlinux.after add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-8 (-8) Function old new delta arch_timer_register 1724 1716 -8 Total: Before=69177808, After=69177800, chg -0.00% Cc: Jisheng Zhang <jszhang@kernel.org> Cc: Ionela Voinescu <ionela.voinescu@arm.com> Cc: Marc Zyngier <maz@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Stephen Boyd <swboyd@chromium.org> --- drivers/clocksource/arm_arch_timer.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) base-commit: 4cece764965020c22cff7665b18a012006359095