Merge tag 'powerpc-4.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux (180d89f6) · Commits · 戴 / test

Documentation/powerpc/transactional_memory.txt

+16 −16

Original line number	Diff line number	Diff line
		@@ -74,23 +74,22 @@ Causes of transaction aborts
		Syscalls
		========

		Syscalls made from within an active transaction will not be performed and the
		transaction will be doomed by the kernel with the failure code TM_CAUSE_SYSCALL
		\| TM_CAUSE_PERSISTENT.
		Performing syscalls from within transaction is not recommended, and can lead
		to unpredictable results.

		Syscalls made from within a suspended transaction are performed as normal and
		the transaction is not explicitly doomed by the kernel. However, what the
		kernel does to perform the syscall may result in the transaction being doomed
		by the hardware. The syscall is performed in suspended mode so any side
		effects will be persistent, independent of transaction success or failure. No
		guarantees are provided by the kernel about which syscalls will affect
		transaction success.
		Syscalls do not by design abort transactions, but beware: The kernel code will
		not be running in transactional state. The effect of syscalls will always
		remain visible, but depending on the call they may abort your transaction as a
		side-effect, read soon-to-be-aborted transactional data that should not remain
		invisible, etc. If you constantly retry a transaction that constantly aborts
		itself by calling a syscall, you'll have a livelock & make no progress.

		Care must be taken when relying on syscalls to abort during active transactions
		if the calls are made via a library. Libraries may cache values (which may
		give the appearance of success) or perform operations that cause transaction
		failure before entering the kernel (which may produce different failure codes).
		Examples are glibc's getpid() and lazy symbol resolution.
		Simple syscalls (e.g. sigprocmask()) "could" be OK. Even things like write()
		from, say, printf() should be OK as long as the kernel does not access any
		memory that was accessed transactionally.

		Consider any syscalls that happen to work as debug-only -- not recommended for
		production use. Best to queue them up till after the transaction is over.


		Signals
		@@ -177,7 +176,8 @@ kernel aborted a transaction:
		TM_CAUSE_RESCHED Thread was rescheduled.
		TM_CAUSE_TLBI Software TLB invalid.
		TM_CAUSE_FAC_UNAV FP/VEC/VSX unavailable trap.
		TM_CAUSE_SYSCALL Syscall from active transaction.
		TM_CAUSE_SYSCALL Currently unused; future syscalls that must abort
		transactions for consistency will use this.
		TM_CAUSE_SIGNAL Signal delivered.
		TM_CAUSE_MISC Currently unused.
		TM_CAUSE_ALIGNMENT Alignment fault.

arch/powerpc/include/uapi/asm/tm.h

+1 −1

Original line number	Diff line number	Diff line
		@@ -11,7 +11,7 @@
		#define TM_CAUSE_RESCHED 0xde
		#define TM_CAUSE_TLBI 0xdc
		#define TM_CAUSE_FAC_UNAV 0xda
		#define TM_CAUSE_SYSCALL 0xd8
		#define TM_CAUSE_SYSCALL 0xd8 /* future use */
		#define TM_CAUSE_MISC 0xd6 /* future use */
		#define TM_CAUSE_SIGNAL 0xd4
		#define TM_CAUSE_ALIGNMENT 0xd2

arch/powerpc/kernel/eeh.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -749,21 +749,24 @@ int pcibios_set_pcie_reset_state(struct pci_dev *dev, enum pcie_reset_state stat
		eeh_unfreeze_pe(pe, false);
		eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED);
		eeh_pe_dev_traverse(pe, eeh_restore_dev_state, dev);
		eeh_pe_state_clear(pe, EEH_PE_ISOLATED);
		break;
		case pcie_hot_reset:
		eeh_pe_state_mark(pe, EEH_PE_ISOLATED);
		eeh_ops->set_option(pe, EEH_OPT_FREEZE_PE);
		eeh_pe_dev_traverse(pe, eeh_disable_and_save_dev_state, dev);
		eeh_pe_state_mark(pe, EEH_PE_CFG_BLOCKED);
		eeh_ops->reset(pe, EEH_RESET_HOT);
		break;
		case pcie_warm_reset:
		eeh_pe_state_mark(pe, EEH_PE_ISOLATED);
		eeh_ops->set_option(pe, EEH_OPT_FREEZE_PE);
		eeh_pe_dev_traverse(pe, eeh_disable_and_save_dev_state, dev);
		eeh_pe_state_mark(pe, EEH_PE_CFG_BLOCKED);
		eeh_ops->reset(pe, EEH_RESET_FUNDAMENTAL);
		break;
		default:
		eeh_pe_state_clear(pe, EEH_PE_CFG_BLOCKED);
		eeh_pe_state_clear(pe, EEH_PE_ISOLATED \| EEH_PE_CFG_BLOCKED);
		return -EINVAL;
		};

		@@ -1058,6 +1061,9 @@ void eeh_add_device_early(struct pci_dn *pdn)
		if (!edev \|\| !eeh_enabled())
		return;

		if (!eeh_has_flag(EEH_PROBE_MODE_DEVTREE))
		return;

		/* USB Bus children of PCI devices will not have BUID's */
		phb = edev->phb;
		if (NULL == phb \|\|
		@@ -1112,6 +1118,9 @@ void eeh_add_device_late(struct pci_dev *dev)
		return;
		}

		if (eeh_has_flag(EEH_PROBE_MODE_DEV))
		eeh_ops->probe(pdn, NULL);

		/*
		* The EEH cache might not be removed correctly because of
		* unbalanced kref to the device during unplug time, which

arch/powerpc/kernel/entry_64.S

+0 −19

Original line number	Diff line number	Diff line
		@@ -34,7 +34,6 @@
		#include <asm/ftrace.h>
		#include <asm/hw_irq.h>
		#include <asm/context_tracking.h>
		#include <asm/tm.h>

		/*
		* System calls.
		@@ -146,24 +145,6 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR)
		andi. r11,r10,_TIF_SYSCALL_DOTRACE
		bne syscall_dotrace
		.Lsyscall_dotrace_cont:
		#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
		BEGIN_FTR_SECTION
		b 1f
		END_FTR_SECTION_IFCLR(CPU_FTR_TM)
		extrdi. r11, r12, 1, (63-MSR_TS_T_LG) /* transaction active? */
		beq+ 1f

		/* Doom the transaction and don't perform the syscall: */
		mfmsr r11
		li r12, 1
		rldimi r11, r12, MSR_TM_LG, 63-MSR_TM_LG
		mtmsrd r11, 0
		li r11, (TM_CAUSE_SYSCALL\|TM_CAUSE_PERSISTENT)
		TABORT(R11)

		b .Lsyscall_exit
		1:
		#endif
		cmpldi 0,r0,NR_syscalls
		bge- syscall_enosys

arch/powerpc/kernel/idle_power7.S

+2 −0

Original line number	Diff line number	Diff line
		@@ -501,9 +501,11 @@ BEGIN_FTR_SECTION
		CHECK_HMI_INTERRUPT
		END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
		ld r1,PACAR1(r13)
		ld r6,_CCR(r1)
		ld r4,_MSR(r1)
		ld r5,_NIP(r1)
		addi r1,r1,INT_FRAME_SIZE
		mtcr r6
		mtspr SPRN_SRR1,r4
		mtspr SPRN_SRR0,r5
		rfid

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