From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathieu Desnoyers Subject: [RFC PATCH v7 2/7] tracing: instrument restartable sequences Date: Thu, 21 Jul 2016 17:14:17 -0400 Message-ID: <1469135662-31512-3-git-send-email-mathieu.desnoyers@efficios.com> References: <1469135662-31512-1-git-send-email-mathieu.desnoyers@efficios.com> Return-path: In-Reply-To: <1469135662-31512-1-git-send-email-mathieu.desnoyers@efficios.com> Sender: linux-kernel-owner@vger.kernel.org To: Andrew Morton , Russell King , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" Cc: linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, Paul Turner , Andrew Hunter , Peter Zijlstra , Andy Lutomirski , Andi Kleen , Dave Watson , Chris Lameter , Ben Maurer , Steven Rostedt , "Paul E. McKenney" , Josh Triplett , Linus Torvalds , Catalin Marinas , Will Deacon , Michael Kerrisk , Boqun Feng , Mathieu Desnoyers List-Id: linux-api@vger.kernel.org Signed-off-by: Mathieu Desnoyers CC: Thomas Gleixner CC: Paul Turner CC: Andrew Hunter CC: Peter Zijlstra CC: Andy Lutomirski CC: Andi Kleen CC: Dave Watson CC: Chris Lameter CC: Ingo Molnar CC: "H. Peter Anvin" CC: Ben Maurer CC: Steven Rostedt CC: "Paul E. McKenney" CC: Josh Triplett CC: Linus Torvalds CC: Andrew Morton CC: Russell King CC: Catalin Marinas CC: Will Deacon CC: Michael Kerrisk CC: Boqun Feng CC: linux-api@vger.kernel.org --- include/trace/events/rseq.h | 60 +++++++++++++++++++++++++++++++++++++++++++++ kernel/rseq.c | 18 +++++++++++--- 2 files changed, 75 insertions(+), 3 deletions(-) create mode 100644 include/trace/events/rseq.h diff --git a/include/trace/events/rseq.h b/include/trace/events/rseq.h new file mode 100644 index 0000000..83fd31e --- /dev/null +++ b/include/trace/events/rseq.h @@ -0,0 +1,60 @@ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM rseq + +#if !defined(_TRACE_RSEQ_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_RSEQ_H + +#include + +TRACE_EVENT(rseq_inc, + + TP_PROTO(uint32_t event_counter, int ret), + + TP_ARGS(event_counter, ret), + + TP_STRUCT__entry( + __field(uint32_t, event_counter) + __field(int, ret) + ), + + TP_fast_assign( + __entry->event_counter = event_counter; + __entry->ret = ret; + ), + + TP_printk("event_counter=%u ret=%d", + __entry->event_counter, __entry->ret) +); + +TRACE_EVENT(rseq_ip_fixup, + + TP_PROTO(void __user *regs_ip, void __user *post_commit_ip, + void __user *abort_ip, uint32_t kevcount, int ret), + + TP_ARGS(regs_ip, post_commit_ip, abort_ip, kevcount, ret), + + TP_STRUCT__entry( + __field(void __user *, regs_ip) + __field(void __user *, post_commit_ip) + __field(void __user *, abort_ip) + __field(uint32_t, kevcount) + __field(int, ret) + ), + + TP_fast_assign( + __entry->regs_ip = regs_ip; + __entry->post_commit_ip = post_commit_ip; + __entry->abort_ip = abort_ip; + __entry->kevcount = kevcount; + __entry->ret = ret; + ), + + TP_printk("regs_ip=%p post_commit_ip=%p abort_ip=%p kevcount=%u ret=%d", + __entry->regs_ip, __entry->post_commit_ip, __entry->abort_ip, + __entry->kevcount, __entry->ret) +); + +#endif /* _TRACE_SOCK_H */ + +/* This part must be outside protection */ +#include diff --git a/kernel/rseq.c b/kernel/rseq.c index e1c847b..cab326a 100644 --- a/kernel/rseq.c +++ b/kernel/rseq.c @@ -29,6 +29,9 @@ #include #include +#define CREATE_TRACE_POINTS +#include + /* * Each restartable sequence assembly block defines a "struct rseq_cs" * structure which describes the post_commit_ip address, and the @@ -90,8 +93,12 @@ static int rseq_increment_event_counter(struct task_struct *t) { - if (__put_user(++t->rseq_event_counter, - &t->rseq->u.e.event_counter)) + int ret; + + ret = __put_user(++t->rseq_event_counter, + &t->rseq->u.e.event_counter); + trace_rseq_inc(t->rseq_event_counter, ret); + if (ret) return -1; return 0; } @@ -134,8 +141,13 @@ static int rseq_ip_fixup(struct pt_regs *regs) struct task_struct *t = current; void __user *post_commit_ip = NULL; void __user *abort_ip = NULL; + int ret; - if (rseq_get_rseq_cs(t, &post_commit_ip, &abort_ip)) + ret = rseq_get_rseq_cs(t, &post_commit_ip, &abort_ip); + trace_rseq_ip_fixup((void __user *)instruction_pointer(regs), + post_commit_ip, abort_ip, t->rseq_event_counter, + ret); + if (ret) return -1; /* Handle potentially being within a critical section. */ -- 2.1.4