From 14c4000a88afaaa2d0877cc86d42a74fde0f35e0 Mon Sep 17 00:00:00 2001 From: Vasant Hegde Date: Sat, 9 Aug 2014 11:15:30 +0530 Subject: printk: Add function to return log buffer address and size Platforms like IBM Power Systems supports service processor assisted dump. It provides interface to add memory region to be captured when system is crashed. During initialization/running we can add kernel memory region to be collected. Presently we don't have a way to get the log buffer base address and size. This patch adds support to return log buffer address and size. Signed-off-by: Vasant Hegde Signed-off-by: Benjamin Herrenschmidt Acked-by: Andrew Morton --- include/linux/printk.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/linux/printk.h b/include/linux/printk.h index 0990997a5304..d78125f73ac4 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -10,6 +10,9 @@ extern const char linux_banner[]; extern const char linux_proc_banner[]; +extern char *log_buf_addr_get(void); +extern u32 log_buf_len_get(void); + static inline int printk_get_level(const char *buffer) { if (buffer[0] == KERN_SOH_ASCII && buffer[1]) { -- cgit 1.4.1 From 9e813308a5c18c58f9ccae1ec72ed4e14eaf9025 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 13 Aug 2014 12:32:04 +0530 Subject: powerpc/thp: Add tracepoints to track hugepage invalidate Add tracepoint to track hugepage invalidate. This help us in debugging difficult to track bugs. Signed-off-by: Aneesh Kumar K.V Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/mm/pgtable_64.c | 6 +++ arch/powerpc/mm/tlb_hash64.c | 4 ++ include/trace/events/thp.h | 88 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 98 insertions(+) create mode 100644 include/trace/events/thp.h (limited to 'include') diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c index 948a81e02ddb..c8d709ab489d 100644 --- a/arch/powerpc/mm/pgtable_64.c +++ b/arch/powerpc/mm/pgtable_64.c @@ -54,6 +54,9 @@ #include "mmu_decl.h" +#define CREATE_TRACE_POINTS +#include + /* Some sanity checking */ #if TASK_SIZE_USER64 > PGTABLE_RANGE #error TASK_SIZE_USER64 exceeds pagetable range @@ -537,6 +540,7 @@ unsigned long pmd_hugepage_update(struct mm_struct *mm, unsigned long addr, old = pmd_val(*pmdp); *pmdp = __pmd((old & ~clr) | set); #endif + trace_hugepage_update(addr, old, clr, set); if (old & _PAGE_HASHPTE) hpte_do_hugepage_flush(mm, addr, pmdp, old); return old; @@ -642,6 +646,7 @@ void pmdp_splitting_flush(struct vm_area_struct *vma, * If we didn't had the splitting flag set, go and flush the * HPTE entries. */ + trace_hugepage_splitting(address, old); if (!(old & _PAGE_SPLITTING)) { /* We need to flush the hpte */ if (old & _PAGE_HASHPTE) @@ -709,6 +714,7 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr, assert_spin_locked(&mm->page_table_lock); WARN_ON(!pmd_trans_huge(pmd)); #endif + trace_hugepage_set_pmd(addr, pmd); return set_pte_at(mm, addr, pmdp_ptep(pmdp), pmd_pte(pmd)); } diff --git a/arch/powerpc/mm/tlb_hash64.c b/arch/powerpc/mm/tlb_hash64.c index 9adda5790463..d2a94b85dbc2 100644 --- a/arch/powerpc/mm/tlb_hash64.c +++ b/arch/powerpc/mm/tlb_hash64.c @@ -30,6 +30,8 @@ #include #include +#include + DEFINE_PER_CPU(struct ppc64_tlb_batch, ppc64_tlb_batch); /* @@ -213,6 +215,8 @@ void __flush_hash_table_range(struct mm_struct *mm, unsigned long start, if (ptep == NULL) continue; pte = pte_val(*ptep); + if (hugepage_shift) + trace_hugepage_invalidate(start, pte_val(pte)); if (!(pte & _PAGE_HASHPTE)) continue; if (unlikely(hugepage_shift && pmd_trans_huge(*(pmd_t *)pte))) diff --git a/include/trace/events/thp.h b/include/trace/events/thp.h new file mode 100644 index 000000000000..b59b065e9e5d --- /dev/null +++ b/include/trace/events/thp.h @@ -0,0 +1,88 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM thp + +#if !defined(_TRACE_THP_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_THP_H + +#include +#include + +TRACE_EVENT(hugepage_invalidate, + + TP_PROTO(unsigned long addr, unsigned long pte), + TP_ARGS(addr, pte), + TP_STRUCT__entry( + __field(unsigned long, addr) + __field(unsigned long, pte) + ), + + TP_fast_assign( + __entry->addr = addr; + __entry->pte = pte; + ), + + TP_printk("hugepage invalidate at addr 0x%lx and pte = 0x%lx", + __entry->addr, __entry->pte) +); + +TRACE_EVENT(hugepage_set_pmd, + + TP_PROTO(unsigned long addr, unsigned long pmd), + TP_ARGS(addr, pmd), + TP_STRUCT__entry( + __field(unsigned long, addr) + __field(unsigned long, pmd) + ), + + TP_fast_assign( + __entry->addr = addr; + __entry->pmd = pmd; + ), + + TP_printk("Set pmd with 0x%lx with 0x%lx", __entry->addr, __entry->pmd) +); + + +TRACE_EVENT(hugepage_update, + + TP_PROTO(unsigned long addr, unsigned long pte, unsigned long clr, unsigned long set), + TP_ARGS(addr, pte, clr, set), + TP_STRUCT__entry( + __field(unsigned long, addr) + __field(unsigned long, pte) + __field(unsigned long, clr) + __field(unsigned long, set) + ), + + TP_fast_assign( + __entry->addr = addr; + __entry->pte = pte; + __entry->clr = clr; + __entry->set = set; + + ), + + TP_printk("hugepage update at addr 0x%lx and pte = 0x%lx clr = 0x%lx, set = 0x%lx", __entry->addr, __entry->pte, __entry->clr, __entry->set) +); +TRACE_EVENT(hugepage_splitting, + + TP_PROTO(unsigned long addr, unsigned long pte), + TP_ARGS(addr, pte), + TP_STRUCT__entry( + __field(unsigned long, addr) + __field(unsigned long, pte) + ), + + TP_fast_assign( + __entry->addr = addr; + __entry->pte = pte; + ), + + TP_printk("hugepage splitting at addr 0x%lx and pte = 0x%lx", + __entry->addr, __entry->pte) +); + +#endif /* _TRACE_THP_H */ + +/* This part must be outside protection */ +#include -- cgit 1.4.1