From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Date: Wed, 08 Jun 2022 14:27:30 +0000 Subject: [PATCH 07/36] cpuidle,tegra: Push RCU-idle into driver Message-Id: <20220608144516.362668063@infradead.org> List-Id: References: <20220608142723.103523089@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: peterz@infradead.org Cc: rth@twiddle.net, ink@jurassic.park.msu.ru, mattst88@gmail.com, vgupta@kernel.org, linux@armlinux.org.uk, ulli.kroll@googlemail.com, linus.walleij@linaro.org, shawnguo@kernel.org, Sascha Hauer , kernel@pengutronix.de, festevam@gmail.com, linux-imx@nxp.com, tony@atomide.com, khilman@kernel.org, catalin.marinas@arm.com, will@kernel.org, guoren@kernel.org, bcain@quicinc.com, chenhuacai@kernel.org, kernel@xen0n.name, geert@linux-m68k.org, sammy@sammy.net, monstr@monstr.eu, tsbogend@alpha.franken.de, dinguyen@kernel.org, jonas@southpole.se, stefan.kristiansson@saunalahti.fi, shorne@gmail.com, James.Bottomley@HansenPartnership.com, deller@gmx.de, mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, hca@linux.ibm.com, gor@linux.ibm.com, agordeev@linux.ibm.com, borntraeger@linux.ibm.com, svens@linux.ibm.com, ysato@users.sourceforge.jp, dalias@libc.org, davem@davemloft.net, richard@nod.at, anton.ivanov@cambridgegreys.com, johannes@sipsolutions.net, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, acme@kernel.org, mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@kernel.org, namhyung@kernel.org, jgross@suse.com, srivatsa@csail.mit.edu, amakhalov@vmware.com, pv-drivers@vmware.com, boris.ostrovsky@oracle.com, chris@zankel.net, jcmvbkbc@gmail.com, rafael@kernel.org, lenb@kernel.org, pavel@ucw.cz, gregkh@linuxfoundation.org, mturquette@baylibre.com, sboyd@kernel.org, daniel.lezcano@linaro.org, lpieralisi@kernel.org, sudeep.holla@arm.com, agross@kernel.org, bjorn.andersson@linaro.org, anup@brainfault.org, thierry.reding@gmail.com, jonathanh@nvidia.com, jacob.jun.pan@linux.intel.com, Arnd Bergmann , yury.norov@gmail.com, andriy.shevchenko@linux.intel.com, linux@rasmusvillemoes.dk, rostedt@goodmis.org, pmladek@suse.com, senozhatsky@chromium.org, john.ogness@linutronix.de, paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, joel@joelfernandes.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, jpoimboe@kernel.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, linux-csky@vger.kernel.org, linux-hexagon@vger.kernel.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, linux-perf-users@vger.kernel.org, virtualization@lists.linux-foundation.org, xen-devel@lists.xenproject.org, linux-xtensa@linux-xtensa.org, linux-acpi@vger.kernel.org, linux-pm@vger.kernel.org, linux-clk@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-tegra@vger.kernel.org, linux-arch@vger.kernel.org, rcu@vger.kernel.org Doing RCU-idle outside the driver, only to then temporarily enable it again, at least twice, before going idle is daft. Signed-off-by: Peter Zijlstra (Intel) --- drivers/cpuidle/cpuidle-tegra.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-) --- a/drivers/cpuidle/cpuidle-tegra.c +++ b/drivers/cpuidle/cpuidle-tegra.c @@ -180,9 +180,11 @@ static int tegra_cpuidle_state_enter(str } local_fiq_disable(); - RCU_NONIDLE(tegra_pm_set_cpu_in_lp2()); + tegra_pm_set_cpu_in_lp2(); cpu_pm_enter(); + rcu_idle_enter(); + switch (index) { case TEGRA_C7: err = tegra_cpuidle_c7_enter(); @@ -197,8 +199,10 @@ static int tegra_cpuidle_state_enter(str break; } + rcu_idle_exit(); + cpu_pm_exit(); - RCU_NONIDLE(tegra_pm_clear_cpu_in_lp2()); + tegra_pm_clear_cpu_in_lp2(); local_fiq_enable(); return err ?: index; @@ -226,6 +230,7 @@ static int tegra_cpuidle_enter(struct cp struct cpuidle_driver *drv, int index) { + bool do_rcu = drv->states[index].flags & CPUIDLE_FLAG_RCU_IDLE; unsigned int cpu = cpu_logical_map(dev->cpu); int ret; @@ -233,9 +238,13 @@ static int tegra_cpuidle_enter(struct cp if (dev->states_usage[index].disable) return -1; - if (index = TEGRA_C1) + if (index = TEGRA_C1) { + if (do_rcu) + rcu_idle_enter(); ret = arm_cpuidle_simple_enter(dev, drv, index); - else + if (do_rcu) + rcu_idle_exit(); + } else ret = tegra_cpuidle_state_enter(dev, index, cpu); if (ret < 0) { @@ -285,7 +294,8 @@ static struct cpuidle_driver tegra_idle_ .exit_latency = 2000, .target_residency = 2200, .power_usage = 100, - .flags = CPUIDLE_FLAG_TIMER_STOP, + .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_RCU_IDLE, .name = "C7", .desc = "CPU core powered off", }, @@ -295,6 +305,7 @@ static struct cpuidle_driver tegra_idle_ .target_residency = 10000, .power_usage = 0, .flags = CPUIDLE_FLAG_TIMER_STOP | + CPUIDLE_FLAG_RCU_IDLE | CPUIDLE_FLAG_COUPLED, .name = "CC6", .desc = "CPU cluster powered off",