Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753131AbbGBNv0 (ORCPT ); Thu, 2 Jul 2015 09:51:26 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:29656 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753159AbbGBNvO (ORCPT ); Thu, 2 Jul 2015 09:51:14 -0400 From: He Kuang To: , , , , , , , CC: , , Subject: [RFC PATCH v2 4/4] tracing/kprobe: Combine bpf output and perf event output Date: Thu, 2 Jul 2015 13:50:43 +0000 Message-ID: <1435845043-107196-5-git-send-email-hekuang@huawei.com> X-Mailer: git-send-email 1.8.3.4 In-Reply-To: <1435845043-107196-1-git-send-email-hekuang@huawei.com> References: <559386D7.1020208@huawei.com> <1435845043-107196-1-git-send-email-hekuang@huawei.com> MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.107.197.210] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3461 Lines: 103 Check and collect temporary trace buffer in the stage of preparing perf trace buffer. If there're data to be collected, set invalid flag, extend the trace buffer size and move the data to proper offset, so the combined data will be compatible to the orignal format and can be processed by perf-script. Signed-off-by: He Kuang --- kernel/trace/trace_kprobe.c | 36 ++++++++++++++++++++++++++++++++++-- 1 file changed, 34 insertions(+), 2 deletions(-) diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 16ad88e..274735b 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1140,6 +1140,8 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) struct hlist_head *head; int size, __size, dsize; int rctx; + u32 buf_tail_size; + char *buf_tail; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) @@ -1152,15 +1154,29 @@ kprobe_perf_func(struct trace_kprobe *tk, struct pt_regs *regs) if (prog && !trace_call_bpf(prog, regs)) goto out; + /* Check trace buf */ + buf_tail = get_perf_trace_buf(rctx) + + PERF_MAX_TRACE_SIZE - sizeof(u32); + buf_tail_size = *(u32 *)buf_tail; + + /* Clear size to invalid buf */ + *(u32 *)buf_tail = 0; + + if (buf_tail_size != 0) + buf_tail -= buf_tail_size; + dsize = __get_data_size(&tk->tp, regs); __size = sizeof(*entry) + tk->tp.size + dsize; - size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size = ALIGN(__size + buf_tail_size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); entry = perf_trace_buf_prepare_rctx(size, call->event.type, NULL, rctx); if (!entry) goto out; + /* Move temporary buf to proper offset */ + memmove((char *)entry + __size, buf_tail, buf_tail_size); + entry->ip = (unsigned long)tk->rp.kp.addr; memset(&entry[1], 0, dsize); store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); @@ -1183,6 +1199,8 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, struct hlist_head *head; int size, __size, dsize; int rctx; + u32 buf_tail_size; + char *buf_tail; head = this_cpu_ptr(call->perf_events); if (hlist_empty(head)) @@ -1195,15 +1213,29 @@ kretprobe_perf_func(struct trace_kprobe *tk, struct kretprobe_instance *ri, if (prog && !trace_call_bpf(prog, regs)) goto out; + /* Check trace buf */ + buf_tail = get_perf_trace_buf(rctx) + + PERF_MAX_TRACE_SIZE - sizeof(u32); + buf_tail_size = *(u32 *)buf_tail; + + /* Clear size to invalid buf */ + *(u32 *)buf_tail = 0; + + if (buf_tail_size != 0) + buf_tail -= buf_tail_size; + dsize = __get_data_size(&tk->tp, regs); __size = sizeof(*entry) + tk->tp.size + dsize; - size = ALIGN(__size + sizeof(u32), sizeof(u64)); + size = ALIGN(__size + buf_tail_size + sizeof(u32), sizeof(u64)); size -= sizeof(u32); entry = perf_trace_buf_prepare_rctx(size, call->event.type, NULL, rctx); if (!entry) goto out; + /* Move temporary buf to proper offset */ + memmove((char *)entry + __size, buf_tail, buf_tail_size); + entry->func = (unsigned long)tk->rp.kp.addr; entry->ret_ip = (unsigned long)ri->ret_addr; store_trace_args(sizeof(*entry), &tk->tp, regs, (u8 *)&entry[1], dsize); -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/