From: geoff@infradead.org (Geoff Levand) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v19 01/13] arm64: Add cpus_are_stuck_in_kernel Date: Thu, 16 Jun 2016 23:48:27 +0000 [thread overview] Message-ID: <b8820595fdc768f4d321fb9eeb178a0b0c1cf3f7.1466120418.git.geoff@infradead.org> (raw) In-Reply-To: <cover.1466120418.git.geoff@infradead.org> From: James Morse <james.morse@arm.com> kernel/smp.c has a fancy counter that keeps track of the number of CPUs it marked as not-present and left in cpu_park_loop(). If there are any CPUs spinning in here, kexec will release them once the memory is re-used by the new kernel. Provide a function to expose whether this counter is non-zero, so we can use this when loading a new kexec image, and when calling machine_kexec(). Signed-off-by: James Morse <james.morse@arm.com> [Split off from a larger patch] Signed-off-by: Geoff Levand <geoff@infradead.org> --- arch/arm64/include/asm/smp.h | 10 ++++++++++ arch/arm64/kernel/smp.c | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index 433e504..38712f4 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -124,6 +124,16 @@ static inline void cpu_panic_kernel(void) cpu_park_loop(); } +/* + * If a secondary CPU fails to come online, (e.g. due to mismatched features), + * it will try to call cpu_die(). If this fails, it updates + * cpus_stuck_in_kernel and sits in cpu_park_loop(). + * + * Kexec checks this counter and refuses to load/kexec if it is non-zero, as + * cpu_park_loop() would be overwritten releasing the parked cpus. + */ +bool cpus_are_stuck_in_kernel(void); + #endif /* ifndef __ASSEMBLY__ */ #endif /* ifndef __ASM_SMP_H */ diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 678e084..d0bcd55 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -909,3 +909,8 @@ int setup_profiling_timer(unsigned int multiplier) { return -EINVAL; } + +bool cpus_are_stuck_in_kernel(void) +{ + return !!cpus_stuck_in_kernel; +} -- 2.5.0
WARNING: multiple messages have this Message-ID (diff)
From: Geoff Levand <geoff@infradead.org> To: Catalin Marinas <catalin.marinas@arm.com>, Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com>, marc.zyngier@arm.com, kexec@lists.infradead.org, AKASHI Takahiro <takahiro.akashi@linaro.org>, James Morse <james.morse@arm.com>, linux-arm-kernel@lists.infradead.org Subject: [PATCH v19 01/13] arm64: Add cpus_are_stuck_in_kernel Date: Thu, 16 Jun 2016 23:48:27 +0000 [thread overview] Message-ID: <b8820595fdc768f4d321fb9eeb178a0b0c1cf3f7.1466120418.git.geoff@infradead.org> (raw) In-Reply-To: <cover.1466120418.git.geoff@infradead.org> From: James Morse <james.morse@arm.com> kernel/smp.c has a fancy counter that keeps track of the number of CPUs it marked as not-present and left in cpu_park_loop(). If there are any CPUs spinning in here, kexec will release them once the memory is re-used by the new kernel. Provide a function to expose whether this counter is non-zero, so we can use this when loading a new kexec image, and when calling machine_kexec(). Signed-off-by: James Morse <james.morse@arm.com> [Split off from a larger patch] Signed-off-by: Geoff Levand <geoff@infradead.org> --- arch/arm64/include/asm/smp.h | 10 ++++++++++ arch/arm64/kernel/smp.c | 5 +++++ 2 files changed, 15 insertions(+) diff --git a/arch/arm64/include/asm/smp.h b/arch/arm64/include/asm/smp.h index 433e504..38712f4 100644 --- a/arch/arm64/include/asm/smp.h +++ b/arch/arm64/include/asm/smp.h @@ -124,6 +124,16 @@ static inline void cpu_panic_kernel(void) cpu_park_loop(); } +/* + * If a secondary CPU fails to come online, (e.g. due to mismatched features), + * it will try to call cpu_die(). If this fails, it updates + * cpus_stuck_in_kernel and sits in cpu_park_loop(). + * + * Kexec checks this counter and refuses to load/kexec if it is non-zero, as + * cpu_park_loop() would be overwritten releasing the parked cpus. + */ +bool cpus_are_stuck_in_kernel(void); + #endif /* ifndef __ASSEMBLY__ */ #endif /* ifndef __ASM_SMP_H */ diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 678e084..d0bcd55 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -909,3 +909,8 @@ int setup_profiling_timer(unsigned int multiplier) { return -EINVAL; } + +bool cpus_are_stuck_in_kernel(void) +{ + return !!cpus_stuck_in_kernel; +} -- 2.5.0 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec
next prev parent reply other threads:[~2016-06-16 23:48 UTC|newest] Thread overview: 52+ messages / expand[flat|nested] mbox.gz Atom feed top 2016-06-16 23:48 [PATCH v19 00/13] arm64 kexec kernel patches Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 05/13] arm64/kexec: Add pr_debug output Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-20 16:06 ` James Morse 2016-06-20 16:06 ` James Morse 2016-06-20 16:50 ` Geoff Levand 2016-06-20 16:50 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 02/13] arm64: Add back cpu reset routines Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 04/13] arm64/kexec: Enable kexec in the arm64 defconfig Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` Geoff Levand [this message] 2016-06-16 23:48 ` [PATCH v19 01/13] arm64: Add cpus_are_stuck_in_kernel Geoff Levand 2016-06-16 23:48 ` [PATCH v19 03/13] arm64/kexec: Add core kexec support Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-20 15:36 ` James Morse 2016-06-20 15:36 ` James Morse 2016-06-20 16:49 ` Geoff Levand 2016-06-20 16:49 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 11/13] arm64: kdump: enable kdump in the arm64 defconfig Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 13/13] Documentation: dt: usable-memory and elfcorehdr nodes for arm64 kexec Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 12/13] arm64: kdump: update a kernel doc Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 10/13] arm64: kdump: add VMCOREINFO's for user-space coredump tools Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-20 5:32 ` Pratyush Anand 2016-06-20 5:32 ` Pratyush Anand 2016-06-22 5:59 ` AKASHI Takahiro 2016-06-22 5:59 ` AKASHI Takahiro 2016-06-23 7:14 ` Pratyush Anand 2016-06-23 7:14 ` Pratyush Anand 2016-06-23 8:42 ` AKASHI Takahiro 2016-06-23 8:42 ` AKASHI Takahiro 2016-06-23 15:46 ` Pratyush Anand 2016-06-23 15:46 ` Pratyush Anand 2016-06-30 0:44 ` AKASHI Takahiro 2016-06-30 0:44 ` AKASHI Takahiro 2016-06-16 23:48 ` [PATCH v19 07/13] arm64: limit memory regions based on DT property, usable-memory Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 08/13] arm64: kdump: implement machine_crash_shutdown() Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-16 23:48 ` [PATCH v19 06/13] arm64: kdump: reserve memory for crash dump kernel Geoff Levand 2016-06-16 23:48 ` Geoff Levand 2016-06-20 16:07 ` James Morse 2016-06-20 16:07 ` James Morse 2016-06-21 1:23 ` AKASHI Takahiro 2016-06-21 1:23 ` AKASHI Takahiro 2016-06-16 23:48 ` [PATCH v19 09/13] arm64: kdump: add kdump support Geoff Levand 2016-06-16 23:48 ` Geoff Levand
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