[PATCH 1/2] powerpc/smp: Support more IPI messages
From: Suresh Warrier <hidden>
Date: 2015-10-29 23:40:59
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Michael Ellerman, Linus Torvalds
This patch increases the number of demuxed messages for a controller with a single ipi to 8 for 64-bit systems This is required because we want to use the IPI mechanism to send messages from a CPU running in KVM real mode in a guest to a CPU in the host to take some action. Currently, we only support 4 messages and all 4 are already taken. Define a fifth message PPC_MSG_RM_HOST_ACTION for this purpose. Signed-off-by: Suresh Warrier <redacted> --- arch/powerpc/include/asm/smp.h | 3 +++ arch/powerpc/kernel/smp.c | 8 ++++---- 2 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h
index 825663c..9ef9c37 100644
--- a/arch/powerpc/include/asm/smp.h
+++ b/arch/powerpc/include/asm/smp.h@@ -114,6 +114,9 @@ extern int cpu_to_core_id(int cpu); #define PPC_MSG_TICK_BROADCAST 2 #define PPC_MSG_DEBUGGER_BREAK 3 +/* This is only used by the powernv kernel */ +#define PPC_MSG_RM_HOST_ACTION 4 + /* for irq controllers that have dedicated ipis per message (4) */ extern int smp_request_message_ipi(int virq, int message); extern const char *smp_ipi_name[];
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index ec9ec20..a53a130 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c@@ -206,7 +206,7 @@ int smp_request_message_ipi(int virq, int msg) #ifdef CONFIG_PPC_SMP_MUXED_IPI struct cpu_messages { - int messages; /* current messages */ + long messages; /* current messages */ unsigned long data; /* data for cause ipi */ }; static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_messages, ipi_message);
@@ -236,15 +236,15 @@ void smp_muxed_ipi_message_pass(int cpu, int msg) } #ifdef __BIG_ENDIAN__ -#define IPI_MESSAGE(A) (1 << (24 - 8 * (A))) +#define IPI_MESSAGE(A) (1uL << ((BITS_PER_LONG - 8) - 8 * (A))) #else -#define IPI_MESSAGE(A) (1 << (8 * (A))) +#define IPI_MESSAGE(A) (1uL << (8 * (A))) #endif irqreturn_t smp_ipi_demux(void) { struct cpu_messages *info = this_cpu_ptr(&ipi_message); - unsigned int all; + unsigned long all; mb(); /* order any irq clear */
--
1.8.3.4