From patchwork Mon Jul 8 03:28:46 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jinjie Ruan X-Patchwork-Id: 13726153 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 79D75C3DA41 for ; Mon, 8 Jul 2024 03:25:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/cJDZRtlzlQScvFLCvCn/LrPGIn+1Uaqls46wGDS1j8=; b=S+CHVuyVioQxz5 eNf9r+MMq2/ZZEpQc1AMrT6khOY+ISawJANOOUXuu2bQwjeYICh+joB0EvyrL3KAlFFP7nUE1cbmW S9PyHKWwr/C4tPKLbTptejJeH+fjDW8aD09NKgpjcXF0LDhb/Tn5MgjVElTMDatqLa7Ntqj2sRPOd xgYlGk1nllIg4tPCO9zMBLNGKM+uNIp+nwOVi6PPrzgTD/z2HNsfmxlMdVSuHWxHaErZ8dhS/GyN2 hVw6JswKbXs1Moo9HezK7qznoJmK2s7No7kQ0TiVTtoWw6qZXHO4H2cWIBFleu/L3Ns262nDDZe5U XLVZaSoM1opvqSFL9bqQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQezy-00000002fI5-236M; Mon, 08 Jul 2024 03:25:06 +0000 Received: from szxga01-in.huawei.com ([45.249.212.187]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQezu-00000002fGD-4Bf2 for linux-riscv@lists.infradead.org; Mon, 08 Jul 2024 03:25:05 +0000 Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4WHTs85hb7zxVB2; Mon, 8 Jul 2024 11:20:28 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id 6ECFF1800C7; Mon, 8 Jul 2024 11:24:46 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemi100008.china.huawei.com (7.221.188.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Mon, 8 Jul 2024 11:24:45 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH v3 1/2] riscv: Fix fp alignment bug in perf_callchain_user() Date: Mon, 8 Jul 2024 11:28:46 +0800 Message-ID: <20240708032847.2998158-2-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240708032847.2998158-1-ruanjinjie@huawei.com> References: <20240708032847.2998158-1-ruanjinjie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi100008.china.huawei.com (7.221.188.57) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240707_202503_232215_F80FB143 X-CRM114-Status: UNSURE ( 8.99 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org The standard RISC-V calling convention said: "The stack grows downward and the stack pointer is always kept 16-byte aligned". So perf_callchain_user() should check whether 16-byte aligned for fp. Link: https://riscv.org/wp-content/uploads/2015/01/riscv-calling.pdf Fixes: dbeb90b0c1eb ("riscv: Add perf callchain support") Signed-off-by: Jinjie Ruan Cc: Björn Töpel --- arch/riscv/kernel/perf_callchain.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c index 3348a61de7d9..2932791e9388 100644 --- a/arch/riscv/kernel/perf_callchain.c +++ b/arch/riscv/kernel/perf_callchain.c @@ -62,7 +62,7 @@ void perf_callchain_user(struct perf_callchain_entry_ctx *entry, perf_callchain_store(entry, regs->epc); fp = user_backtrace(entry, fp, regs->ra); - while (fp && !(fp & 0x3) && entry->nr < entry->max_stack) + while (fp && !(fp & 0x7) && entry->nr < entry->max_stack) fp = user_backtrace(entry, fp, 0); } From patchwork Mon Jul 8 03:28:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Jinjie Ruan X-Patchwork-Id: 13726154 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 73754C3271E for ; Mon, 8 Jul 2024 03:25:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:CC:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=H88EH2e5X8mOe8ys1khcKCJk1pi1q71u66tk20P/GLA=; b=YOUOdE7P62Y/g6 tELfiC4Bbp6Tw1bTePkhPv20DhdoCzjmdokfsZgpdcZXRHTMbF2LqozfdOAye+H3NZ/XskMi8KVyR HMU+gJcLbqpE6ZlABR/78FNPs8CVfsE+mqUjkygrcnBF7o/SP7KRPYpznQoDpvEI8beXqL4dnHGUm CsNRTh7NDNgAPFNBHc4nGpz3S3qbsvLarVghPW8AyYtPYk0DFAvIk+4vy5hZm4qNNxrDezOsyHQGp mSvRIgHCg9mxM5tggLC4YHJCwe8HonRyTTts+yOuEM+YKG+Mt0mMCOQX1XxdUCyCbNbe5+0XRlh0Q 9vn5GfIPB1veWL0vHCHQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQf0I-00000002fNv-36oD; Mon, 08 Jul 2024 03:25:26 +0000 Received: from szxga08-in.huawei.com ([45.249.212.255]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQf0F-00000002fM9-2YRF for linux-riscv@lists.infradead.org; Mon, 08 Jul 2024 03:25:25 +0000 Received: from mail.maildlp.com (unknown [172.19.162.254]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4WHTsK05h6z1T5Y1; Mon, 8 Jul 2024 11:20:37 +0800 (CST) Received: from kwepemi100008.china.huawei.com (unknown [7.221.188.57]) by mail.maildlp.com (Postfix) with ESMTPS id 7CDA31800C0; Mon, 8 Jul 2024 11:25:01 +0800 (CST) Received: from huawei.com (10.90.53.73) by kwepemi100008.china.huawei.com (7.221.188.57) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Mon, 8 Jul 2024 11:24:46 +0800 From: Jinjie Ruan To: , , , , , , , , , , , , , , , , , , CC: Subject: [PATCH v3 2/2] riscv: stacktrace: Add USER_STACKTRACE support Date: Mon, 8 Jul 2024 11:28:47 +0800 Message-ID: <20240708032847.2998158-3-ruanjinjie@huawei.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240708032847.2998158-1-ruanjinjie@huawei.com> References: <20240708032847.2998158-1-ruanjinjie@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.90.53.73] X-ClientProxiedBy: dggems704-chm.china.huawei.com (10.3.19.181) To kwepemi100008.china.huawei.com (7.221.188.57) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240707_202524_119102_2A1C2E92 X-CRM114-Status: GOOD ( 16.08 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Currently, userstacktrace is unsupported for riscv. So use the perf_callchain_user() code as blueprint to implement the arch_stack_walk_user() which add userstacktrace support on riscv. Meanwhile, we can use arch_stack_walk_user() to simplify the implementation of perf_callchain_user(). A ftrace test case is shown as below: # cd /sys/kernel/debug/tracing # echo 1 > options/userstacktrace # echo 1 > options/sym-userobj # echo 1 > events/sched/sched_process_fork/enable # cat trace ...... bash-178 [000] ...1. 97.968395: sched_process_fork: comm=bash pid=178 child_comm=bash child_pid=231 bash-178 [000] ...1. 97.970075: => /lib/libc.so.6[+0xb5090] Also a simple perf test is ok as below: # perf record -e cpu-clock --call-graph fp top # perf report --call-graph ..... [[31m 66.54%[[m 0.00% top [kernel.kallsyms] [k] ret_from_exception | ---ret_from_exception | |--[[31m58.97%[[m--do_trap_ecall_u | | | |--[[31m17.34%[[m--__riscv_sys_read | | ksys_read | | | | | --[[31m16.88%[[m--vfs_read | | | | | |--[[31m10.90%[[m--seq_read Signed-off-by: Jinjie Ruan Tested-by: Jinjie Ruan Cc: Björn Töpel --- v3: - Remove the LTP message as Björn suggested. - Keep fp 16-bytes aligned in arch_stack_walk_user(). - Add the test info. v2: - Fix the cocci warning, !A || A && B is equivalent to !A || B. --- --- arch/riscv/Kconfig | 1 + arch/riscv/kernel/perf_callchain.c | 46 ++---------------------------- arch/riscv/kernel/stacktrace.c | 43 ++++++++++++++++++++++++++++ 3 files changed, 47 insertions(+), 43 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 3b44e7b51436..46121dbcf750 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -194,6 +194,7 @@ config RISCV select THREAD_INFO_IN_TASK select TRACE_IRQFLAGS_SUPPORT select UACCESS_MEMCPY if !MMU + select USER_STACKTRACE_SUPPORT select ZONE_DMA32 if 64BIT config CLANG_SUPPORTS_DYNAMIC_FTRACE diff --git a/arch/riscv/kernel/perf_callchain.c b/arch/riscv/kernel/perf_callchain.c index 2932791e9388..c7468af77c66 100644 --- a/arch/riscv/kernel/perf_callchain.c +++ b/arch/riscv/kernel/perf_callchain.c @@ -6,37 +6,9 @@ #include -/* - * Get the return address for a single stackframe and return a pointer to the - * next frame tail. - */ -static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry, - unsigned long fp, unsigned long reg_ra) +static bool fill_callchain(void *entry, unsigned long pc) { - struct stackframe buftail; - unsigned long ra = 0; - unsigned long __user *user_frame_tail = - (unsigned long __user *)(fp - sizeof(struct stackframe)); - - /* Check accessibility of one struct frame_tail beyond */ - if (!access_ok(user_frame_tail, sizeof(buftail))) - return 0; - if (__copy_from_user_inatomic(&buftail, user_frame_tail, - sizeof(buftail))) - return 0; - - if (reg_ra != 0) - ra = reg_ra; - else - ra = buftail.ra; - - fp = buftail.fp; - if (ra != 0) - perf_callchain_store(entry, ra); - else - return 0; - - return fp; + return perf_callchain_store(entry, pc) == 0; } /* @@ -56,19 +28,7 @@ static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry, void perf_callchain_user(struct perf_callchain_entry_ctx *entry, struct pt_regs *regs) { - unsigned long fp = 0; - - fp = regs->s0; - perf_callchain_store(entry, regs->epc); - - fp = user_backtrace(entry, fp, regs->ra); - while (fp && !(fp & 0x7) && entry->nr < entry->max_stack) - fp = user_backtrace(entry, fp, 0); -} - -static bool fill_callchain(void *entry, unsigned long pc) -{ - return perf_callchain_store(entry, pc) == 0; + arch_stack_walk_user(fill_callchain, entry, regs); } void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index 0d3f00eb0bae..5480cc11b523 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -161,3 +161,46 @@ noinline noinstr void arch_stack_walk(stack_trace_consume_fn consume_entry, void { walk_stackframe(task, regs, consume_entry, cookie); } + +/* + * Get the return address for a single stackframe and return a pointer to the + * next frame tail. + */ +static unsigned long unwind_user_frame(stack_trace_consume_fn consume_entry, + void *cookie, unsigned long fp, + unsigned long reg_ra) +{ + struct stackframe buftail; + unsigned long ra = 0; + unsigned long __user *user_frame_tail = + (unsigned long __user *)(fp - sizeof(struct stackframe)); + + /* Check accessibility of one struct frame_tail beyond */ + if (!access_ok(user_frame_tail, sizeof(buftail))) + return 0; + if (__copy_from_user_inatomic(&buftail, user_frame_tail, + sizeof(buftail))) + return 0; + + ra = reg_ra ? : buftail.ra; + + fp = buftail.fp; + if (!ra || !consume_entry(cookie, ra)) + return 0; + + return fp; +} + +void arch_stack_walk_user(stack_trace_consume_fn consume_entry, void *cookie, + const struct pt_regs *regs) +{ + unsigned long fp = 0; + + fp = regs->s0; + if (!consume_entry(cookie, regs->epc)) + return; + + fp = unwind_user_frame(consume_entry, cookie, fp, regs->ra); + while (fp && !(fp & 0x7)) + fp = unwind_user_frame(consume_entry, cookie, fp, 0); +}