From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jack Steiner Date: Sun, 11 Jul 2004 13:47:27 +0000 Subject: [PATCH] - Reduce TLB flushing during process migration Message-Id: <20040711134727.GA8966@sgi.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Here is the updated "Reduce TLB flushing during process migration" patch. The patch is essentially the same as the previous - only updated to fit on top of the recent machvec changes. Signed-off-by: Jack Steiner --- linux_base/include/asm-ia64/machvec_sn2.h 2004-07-10 17:12:14.000000000 -0500 +++ linux/include/asm-ia64/machvec_sn2.h 2004-07-10 19:14:00.000000000 -0500 @@ -39,6 +39,7 @@ extern ia64_mv_irq_init_t sn_irq_init; extern ia64_mv_send_ipi_t sn2_send_IPI; extern ia64_mv_timer_interrupt_t sn_timer_interrupt; extern ia64_mv_global_tlb_purge_t sn2_global_tlb_purge; +extern ia64_mv_tlb_migrate_finish_t sn_tlb_migrate_finish; extern ia64_mv_irq_desc sn_irq_desc; extern ia64_mv_irq_to_vector sn_irq_to_vector; extern ia64_mv_local_vector_to_irq sn_local_vector_to_irq; @@ -83,6 +84,7 @@ extern ia64_mv_dma_supported sn_dma_sup #define platform_send_ipi sn2_send_IPI #define platform_timer_interrupt sn_timer_interrupt #define platform_global_tlb_purge sn2_global_tlb_purge +#define platform_tlb_migrate_finish sn_tlb_migrate_finish #define platform_pci_fixup sn_pci_fixup #define platform_inb __sn_inb #define platform_inw __sn_inw --- linux_base/include/asm-generic/tlb.h 2004-07-10 17:12:13.000000000 -0500 +++ linux/include/asm-generic/tlb.h 2004-07-10 19:14:00.000000000 -0500 @@ -147,4 +147,6 @@ static inline void tlb_remove_page(struc __pmd_free_tlb(tlb, pmdp); \ } while (0) +#define tlb_migrate_finish(mm) do {} while (0) + #endif /* _ASM_GENERIC__TLB_H */ --- linux_base/Documentation/cachetlb.txt 2004-07-10 17:12:03.000000000 -0500 +++ linux/Documentation/cachetlb.txt 2004-07-10 19:14:00.000000000 -0500 @@ -132,6 +132,17 @@ changes occur: translations for software managed TLB configurations. The sparc64 port currently does this. +7) void tlb_migrate_finish(struct mm_struct *mm) + + This interface is called at the end of an explicit + process migration. This interface provides a hook + to allow a platform to update TLB or context-specific + information for the address space. + + The ia64 sn2 platform is one example of a platform + that uses this interface. + + Next, we have the cache flushing interfaces. In general, when Linux is changing an existing virtual-->physical mapping to a new value, the sequence will be in one of the following forms: --- linux_base/arch/ia64/sn/kernel/sn2/sn2_smp.c 2004-07-10 17:12:04.000000000 -0500 +++ linux/arch/ia64/sn/kernel/sn2/sn2_smp.c 2004-07-10 19:14:00.000000000 -0500 @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include @@ -60,6 +61,13 @@ wait_piowc(void) } +void +sn_tlb_migrate_finish(struct mm_struct *mm) +{ + if (mm = current->mm) + flush_tlb_mm(mm); +} + /** * sn2_global_tlb_purge - globally purge translation cache of virtual address range @@ -114,6 +122,13 @@ sn2_global_tlb_purge (unsigned long star return; } + if (atomic_read(&mm->mm_users) = 1) { + flush_tlb_mm(mm); + preempt_enable(); + return; + } + + nix = 0; for (cnode=find_first_bit(&nodes_flushed, NR_NODES); cnode < NR_NODES; cnode=find_next_bit(&nodes_flushed, NR_NODES, ++cnode)) --- linux_base/kernel/sched.c 2004-07-10 17:12:17.000000000 -0500 +++ linux/kernel/sched.c 2004-07-10 19:14:00.000000000 -0500 @@ -40,6 +40,7 @@ #include #include #include +#include #include @@ -3349,6 +3350,7 @@ int set_cpus_allowed(task_t *p, cpumask_ task_rq_unlock(rq, &flags); wake_up_process(rq->migration_thread); wait_for_completion(&req.done); + tlb_migrate_finish(p->mm); return 0; } out: --- linux_base/include/asm-ia64/tlb.h 2004-07-10 17:12:14.000000000 -0500 +++ linux/include/asm-ia64/tlb.h 2004-07-10 19:14:00.000000000 -0500 @@ -44,6 +44,7 @@ #include #include #include +#include #ifdef CONFIG_SMP # define FREE_PTE_NR 2048 @@ -211,6 +212,8 @@ __tlb_remove_tlb_entry (struct mmu_gathe tlb->end_addr = address + PAGE_SIZE; } +#define tlb_migrate_finish(mm) platform_tlb_migrate_finish(mm) + #define tlb_start_vma(tlb, vma) do { } while (0) #define tlb_end_vma(tlb, vma) do { } while (0) --- linux_base/include/asm-ia64/machvec.h 2004-07-10 17:12:14.000000000 -0500 +++ linux/include/asm-ia64/machvec.h 2004-07-10 19:14:00.000000000 -0500 @@ -19,6 +19,7 @@ struct pt_regs; struct scatterlist; struct irq_desc; struct page; +struct mm_struct; typedef void ia64_mv_setup_t (char **); typedef void ia64_mv_cpu_init_t (void); @@ -26,6 +27,7 @@ typedef void ia64_mv_irq_init_t (void); typedef void ia64_mv_send_ipi_t (int, int, int, int); typedef void ia64_mv_timer_interrupt_t (int, void *, struct pt_regs *); typedef void ia64_mv_global_tlb_purge_t (unsigned long, unsigned long, unsigned long); +typedef void ia64_mv_tlb_migrate_finish_t (struct mm_struct *); typedef struct irq_desc *ia64_mv_irq_desc (unsigned int); typedef u8 ia64_mv_irq_to_vector (u8); typedef unsigned int ia64_mv_local_vector_to_irq (u8 vector); @@ -74,10 +76,16 @@ machvec_noop (void) { } +static inline void +machvec_noop_mm (struct mm_struct *mm) +{ +} + extern void machvec_setup (char **); extern void machvec_timer_interrupt (int, void *, struct pt_regs *); extern void machvec_dma_sync_single (struct device *, dma_addr_t, size_t, int); extern void machvec_dma_sync_sg (struct device *, struct scatterlist *, int, int); +extern void machvec_tlb_migrate_finish (struct mm_struct *); # if defined (CONFIG_IA64_HP_SIM) # include @@ -99,6 +107,7 @@ extern void machvec_dma_sync_sg (struct # define platform_send_ipi ia64_mv.send_ipi # define platform_timer_interrupt ia64_mv.timer_interrupt # define platform_global_tlb_purge ia64_mv.global_tlb_purge +# define platform_tlb_migrate_finish ia64_mv.tlb_migrate_finish # define platform_dma_init ia64_mv.dma_init # define platform_dma_alloc_coherent ia64_mv.dma_alloc_coherent # define platform_dma_free_coherent ia64_mv.dma_free_coherent @@ -144,6 +153,7 @@ struct ia64_machine_vector { ia64_mv_send_ipi_t *send_ipi; ia64_mv_timer_interrupt_t *timer_interrupt; ia64_mv_global_tlb_purge_t *global_tlb_purge; + ia64_mv_tlb_migrate_finish_t *tlb_migrate_finish; ia64_mv_dma_init *dma_init; ia64_mv_dma_alloc_coherent *dma_alloc_coherent; ia64_mv_dma_free_coherent *dma_free_coherent; @@ -185,6 +195,7 @@ struct ia64_machine_vector { platform_send_ipi, \ platform_timer_interrupt, \ platform_global_tlb_purge, \ + platform_tlb_migrate_finish, \ platform_dma_init, \ platform_dma_alloc_coherent, \ platform_dma_free_coherent, \ @@ -264,6 +275,9 @@ extern ia64_mv_dma_supported swiotlb_dm #ifndef platform_global_tlb_purge # define platform_global_tlb_purge ia64_global_tlb_purge /* default to architected version */ #endif +#ifndef platform_tlb_migrate_finish +# define platform_tlb_migrate_finish machvec_noop_mm +#endif #ifndef platform_dma_init # define platform_dma_init swiotlb_init #endif -- Thanks Jack Steiner (steiner@sgi.com) 651-683-5302 Principal Engineer SGI - Silicon Graphics, Inc.