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authorMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
committerMauro Carvalho Chehab <mchehab+samsung@kernel.org>2019-02-18 10:12:12 -0500
commit5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0 (patch)
treec8e30ba4eaf357699ef97a786bf56661f4591be8 /arch/riscv/kernel/smp.c
parentmedia: vimc: fill in bus_info in media_device_info (diff)
parentLinux 5.0-rc7 (diff)
downloadlinux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.tar.xz
linux-dev-5f09bc8cc4010a3ea17c5881a62fc45192ebe7b0.zip
Merge tag 'v5.0-rc7' into patchwork
Linux 5.0-rc7 * tag 'v5.0-rc7': (1667 commits) Linux 5.0-rc7 Input: elan_i2c - add ACPI ID for touchpad in Lenovo V330-15ISK Input: st-keyscan - fix potential zalloc NULL dereference Input: apanel - switch to using brightness_set_blocking() powerpc/64s: Fix possible corruption on big endian due to pgd/pud_present() efi/arm: Revert "Defer persistent reservations until after paging_init()" arm64, mm, efi: Account for GICv3 LPI tables in static memblock reserve table sunrpc: fix 4 more call sites that were using stack memory with a scatterlist include/linux/module.h: copy __init/__exit attrs to init/cleanup_module Compiler Attributes: add support for __copy (gcc >= 9) lib/crc32.c: mark crc32_le_base/__crc32c_le_base aliases as __pure auxdisplay: ht16k33: fix potential user-after-free on module unload x86/platform/UV: Use efi_runtime_lock to serialise BIOS calls i2c: bcm2835: Clear current buffer pointers and counts after a transfer i2c: cadence: Fix the hold bit setting drm: Use array_size() when creating lease dm thin: fix bug where bio that overwrites thin block ignores FUA Revert "exec: load_script: don't blindly truncate shebang string" Revert "gfs2: read journal in large chunks to locate the head" net: ethernet: freescale: set FEC ethtool regs version ... Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'arch/riscv/kernel/smp.c')
-rw-r--r--arch/riscv/kernel/smp.c43
1 files changed, 36 insertions, 7 deletions
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index 57b1383e5ef7..246635eac7bb 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -23,6 +23,7 @@
#include <linux/smp.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
+#include <linux/delay.h>
#include <asm/sbi.h>
#include <asm/tlbflush.h>
@@ -31,6 +32,7 @@
enum ipi_message_type {
IPI_RESCHEDULE,
IPI_CALL_FUNC,
+ IPI_CPU_STOP,
IPI_MAX
};
@@ -66,6 +68,13 @@ int setup_profiling_timer(unsigned int multiplier)
return -EINVAL;
}
+static void ipi_stop(void)
+{
+ set_cpu_online(smp_processor_id(), false);
+ while (1)
+ wait_for_interrupt();
+}
+
void riscv_software_interrupt(void)
{
unsigned long *pending_ipis = &ipi_data[smp_processor_id()].bits;
@@ -94,6 +103,11 @@ void riscv_software_interrupt(void)
generic_smp_call_function_interrupt();
}
+ if (ops & (1 << IPI_CPU_STOP)) {
+ stats[IPI_CPU_STOP]++;
+ ipi_stop();
+ }
+
BUG_ON((ops >> IPI_MAX) != 0);
/* Order data access and bit testing. */
@@ -121,6 +135,7 @@ send_ipi_message(const struct cpumask *to_whom, enum ipi_message_type operation)
static const char * const ipi_names[] = {
[IPI_RESCHEDULE] = "Rescheduling interrupts",
[IPI_CALL_FUNC] = "Function call interrupts",
+ [IPI_CPU_STOP] = "CPU stop interrupts",
};
void show_ipi_stats(struct seq_file *p, int prec)
@@ -146,15 +161,29 @@ void arch_send_call_function_single_ipi(int cpu)
send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
}
-static void ipi_stop(void *unused)
-{
- while (1)
- wait_for_interrupt();
-}
-
void smp_send_stop(void)
{
- on_each_cpu(ipi_stop, NULL, 1);
+ unsigned long timeout;
+
+ if (num_online_cpus() > 1) {
+ cpumask_t mask;
+
+ cpumask_copy(&mask, cpu_online_mask);
+ cpumask_clear_cpu(smp_processor_id(), &mask);
+
+ if (system_state <= SYSTEM_RUNNING)
+ pr_crit("SMP: stopping secondary CPUs\n");
+ send_ipi_message(&mask, IPI_CPU_STOP);
+ }
+
+ /* Wait up to one second for other CPUs to stop */
+ timeout = USEC_PER_SEC;
+ while (num_online_cpus() > 1 && timeout--)
+ udelay(1);
+
+ if (num_online_cpus() > 1)
+ pr_warn("SMP: failed to stop secondary CPUs %*pbl\n",
+ cpumask_pr_args(cpu_online_mask));
}
void smp_send_reschedule(int cpu)