xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

x86/smpboot: Remove APIC.wait_for_init_deassert and atomic init_deasserted

Browse Source 
Both the per-APIC flag ".wait_for_init_deassert",
and the global atomic_t "init_deasserted"
are dead code -- remove them.

For all APIC types, "wait_for_master()"
prevents an AP from proceeding until the BSP has set
cpu_callout_mask, making "init_deasserted" {unnecessary}:

	BSP: <de-assert INIT>
	...
	BSP: {set init_deasserted}
	AP: wait_for_master()
		set cpu_initialized_mask
		wait for cpu_callout_mask
	BSP: test cpu_initialized_mask
	BSP: set cpu_callout_mask
	AP: test cpu_callout_mask
	AP: {wait for init_deasserted}
	...
	AP: <touch APIC>

Deleting the {dead code} above is necessary to enable
some parallelism in a future patch.

Signed-off-by: Len Brown <len.brown@intel.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Jan H. Schönherr <jschoenh@amazon.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Link: http://lkml.kernel.org/r/de4b3a9bab894735e285870b5296da25ee6a8a5a.1439739165.git.len.brown@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Len Brown
2015-08-16 11:45:48 -04:00
committed by Ingo Molnar
parent a9bcaa02a5
commit 656bba3068
10 changed files with 3 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
arch/x86/kernel/apic/apic_flat_64.c
View File

@@ -191,7 +191,6 @@ static struct apic apic_flat = {
.send_IPI_all = flat_send_IPI_all,
.send_IPI_self = apic_send_IPI_self,
.wait_for_init_deassert = false,
.inquire_remote_apic = default_inquire_remote_apic,
.read = native_apic_mem_read,
@@ -299,7 +298,6 @@ static struct apic apic_physflat = {
.send_IPI_all = physflat_send_IPI_all,
.send_IPI_self = apic_send_IPI_self,
.wait_for_init_deassert = false,
.inquire_remote_apic = default_inquire_remote_apic,
.read = native_apic_mem_read,

1
arch/x86/kernel/apic/apic_noop.c
View File

@@ -152,7 +152,6 @@ struct apic apic_noop = {
.wakeup_secondary_cpu = noop_wakeup_secondary_cpu,
.wait_for_init_deassert = false,
.inquire_remote_apic = NULL,
.read = noop_apic_read,

2
arch/x86/kernel/apic/apic_numachip.c
View File

@@ -92,7 +92,6 @@ static int numachip_wakeup_secondary(int phys_apicid, unsigned long start_rip)
write_lcsr(CSR_G3_EXT_IRQ_GEN, int_gen.v);
atomic_set(&init_deasserted, 1);
return 0;
}
@@ -235,7 +234,6 @@ static const struct apic apic_numachip __refconst = {
.send_IPI_self = numachip_send_IPI_self,
.wakeup_secondary_cpu = numachip_wakeup_secondary,
.wait_for_init_deassert = false,
.inquire_remote_apic = NULL, /* REMRD not supported */
.read = native_apic_mem_read,

1
arch/x86/kernel/apic/bigsmp_32.c
View File

@@ -186,7 +186,6 @@ static struct apic apic_bigsmp = {
.send_IPI_all = bigsmp_send_IPI_all,
.send_IPI_self = default_send_IPI_self,
.wait_for_init_deassert = true,
.inquire_remote_apic = default_inquire_remote_apic,
.read = native_apic_mem_read,

1
arch/x86/kernel/apic/probe_32.c
View File

@@ -111,7 +111,6 @@ static struct apic apic_default = {
.send_IPI_all = default_send_IPI_all,
.send_IPI_self = default_send_IPI_self,
.wait_for_init_deassert = true,
.inquire_remote_apic = default_inquire_remote_apic,
.read = native_apic_mem_read,

1
arch/x86/kernel/apic/x2apic_cluster.c
View File

@@ -272,7 +272,6 @@ static struct apic apic_x2apic_cluster = {
.send_IPI_all = x2apic_send_IPI_all,
.send_IPI_self = x2apic_send_IPI_self,
.wait_for_init_deassert = false,
.inquire_remote_apic = NULL,
.read = native_apic_msr_read,

1
arch/x86/kernel/apic/x2apic_phys.c
View File

@@ -128,7 +128,6 @@ static struct apic apic_x2apic_phys = {
.send_IPI_all = x2apic_send_IPI_all,
.send_IPI_self = x2apic_send_IPI_self,
.wait_for_init_deassert = false,
.inquire_remote_apic = NULL,
.read = native_apic_msr_read,

2
arch/x86/kernel/apic/x2apic_uv_x.c
View File

@@ -248,7 +248,6 @@ static int uv_wakeup_secondary(int phys_apicid, unsigned long start_rip)
APIC_DM_STARTUP;
uv_write_global_mmr64(pnode, UVH_IPI_INT, val);
atomic_set(&init_deasserted, 1);
return 0;
}
@@ -414,7 +413,6 @@ static struct apic __refdata apic_x2apic_uv_x = {
.send_IPI_self = uv_send_IPI_self,
.wakeup_secondary_cpu = uv_wakeup_secondary,
.wait_for_init_deassert = false,
.inquire_remote_apic = NULL,
.read = native_apic_msr_read,