Received-SPF: pass (google.com: domain of linux-kernel+bounces-62986-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
From: Ankur Arora <ankur.a.arora@oracle.com>
To: linux-kernel@vger.kernel.org
Cc: tglx@linutronix.de, peterz@infradead.org, torvalds@linux-foundation.org,
        paulmck@kernel.org, akpm@linux-foundation.org, luto@kernel.org,
        bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com,
        mingo@redhat.com, juri.lelli@redhat.com, vincent.guittot@linaro.org,
        willy@infradead.org, mgorman@suse.de, jpoimboe@kernel.org,
        mark.rutland@arm.com, jgross@suse.com, andrew.cooper3@citrix.com,
        bristot@kernel.org, mathieu.desnoyers@efficios.com,
        geert@linux-m68k.org, glaubitz@physik.fu-berlin.de,
        anton.ivanov@cambridgegreys.com, mattst88@gmail.com,
        krypton@ulrich-teichert.org, rostedt@goodmis.org,
        David.Laight@ACULAB.COM, richard@nod.at, mjguzik@gmail.com,
        jon.grimm@amd.com, bharata@amd.com, raghavendra.kt@amd.com,
        boris.ostrovsky@oracle.com, konrad.wilk@oracle.com,
        Ankur Arora <ankur.a.arora@oracle.com>,
        Masami Hiramatsu <mhiramat@kernel.org>
Subject: [PATCH 28/30] tracing: support lazy resched
Date: Mon, 12 Feb 2024 21:55:52 -0800
Message-Id: <20240213055554.1802415-29-ankur.a.arora@oracle.com>
In-Reply-To: <20240213055554.1802415-1-ankur.a.arora@oracle.com>
References: <20240213055554.1802415-1-ankur.a.arora@oracle.com>
Content-Transfer-Encoding: 8bit
Content-Type: text/plain
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: 
	=?us-ascii?Q?qoiYsXh639pejsSB5FoL6ve6YV6FHEVKhPm5a+LoVfgMtY7zDMGfjxmnb++X?=
 =?us-ascii?Q?twJ3WnMts4E8uOrIZgqcSqYMBmwaWkrCyfc+PYzfaBt+mOab1tLMxDAdo95F?=
 =?us-ascii?Q?8Y4dQL4G8862RtLPQ3oCgDUoe5GSbmMPCui7LPZGqhfKs0rN1AUD9TA0XSpy?=
 =?us-ascii?Q?K2KKfpiBScOA4m/jb5+H/MsNreFLMCu/u4c8OXrJOtMFiK8EcA+1REsNyHvD?=
 =?us-ascii?Q?zRg/2wr3fw0q/gYc/pKZnIvS/NY/FesHdoyRfJzZxyArKlh5mtM7frCE7eEG?=
 =?us-ascii?Q?hToHPDBl9gI9mg/DayxaEFpR1YpnR9EN5MyhGOP0iZXxSMy53wSX9CG2KsNX?=
 =?us-ascii?Q?f3BeBX+NxENIVbvVe6J6ghh1cAY0c96EuKnDrYMAHjRiA0A1LjOlWUSnq11u?=
 =?us-ascii?Q?hVbM75fg6VC3X6WsN5k2kcuigVPvsuwdn/FX32qv22nv18UdhxJJQq2YXaGQ?=
 =?us-ascii?Q?pr9+XYUjPUsPPDDVVMD5NfDFauzSg19Cm3IgszSoec3FkZVE11pR54iwqDd+?=
 =?us-ascii?Q?oqDM0DMaplslM6W+qy+hO8w5FvkAreR/Vog1iOdz8PlnLDvP/FpRN+Wk9Wrr?=
 =?us-ascii?Q?KHSVIfNQDTiomndXfkr0s/3S1LZmhTquktqowMUM52l8UvYnFOWI39y5ky1z?=
 =?us-ascii?Q?WWI4m0Cmgv8n9GrgknUytFdMjqPXD3ELfzpre0ebdrOvZRD41JjWVF6BczWH?=
 =?us-ascii?Q?9Y7SPQGxdm/4HglhnTNd+RE8/rW/q6Y26z3xW2RvPLk9slIPOkes5Qjl5xlj?=
 =?us-ascii?Q?kYbeBwegaZCaz3Mz4rP0wgzFQFhMIGkvaaWcWyX6WWWz0bzvcHZnRubVqZcl?=
 =?us-ascii?Q?+QJ3xdrRYWeGudidGmO9iTe7/Qk7Vyo8yWNg3OxcedbJcHMsyNOU8+V1KIYP?=
 =?us-ascii?Q?S4Qa/RUXTT1MBocnoDD26BpuFCbZKoRRbctwtcu2z1q12oQBlb6hJuuC8sWW?=
 =?us-ascii?Q?4Vv9i7I1a7kVkaDG7pi9byrX2h2UdV/KsAAD/kYfrjBJmlcCK3uZk/eqfSVH?=
 =?us-ascii?Q?rZtP/DoYhC70SeSbp+X5accRZ7iu4L6fz4mCC+jcpdvNRPkPZXwnE+ZmRiZK?=
 =?us-ascii?Q?O685+CWMkphSU8CSOHhQEF4zNkWwcN08KEG/uC47jGU7CyfDw/ss+WjGIdmj?=
 =?us-ascii?Q?2uTUBIHLNAucdSfYrsyIEnLv0X2B7LYYGsELsRPZfKHMbddnjzGbL0K08paT?=
 =?us-ascii?Q?c/YpDRRJ26Axc7/UL8+Kbsu04SftblAhEwqPRRULjSPwEdN8iGHawq64fq+4?=
 =?us-ascii?Q?uz5tC8R7gkXUnzeDhGitwoiGdTE3mcLe+1FkNSTRIlW03HmyQO96TebsO3C1?=
 =?us-ascii?Q?2TDrK0SBGy4pboXm2UWvMv9srNyvOSdAB6B08taCzpCnBVAlzuJH/vliqHN4?=
 =?us-ascii?Q?IQFtfP6ELL9IBaDN/deCkEMEPTImZ9/iE0dy9fYSGIgHZQsKxCeJCeCaLi4f?=
 =?us-ascii?Q?hhoalZX45TIkFcZBqrHh2AeF4mEu1565kb1YhfrqWIviItWdXDImnlYkggna?=
 =?us-ascii?Q?G8M21VAgUOwZfC58VvVDLyLGfpiBJCjYKRCdpHGtNjbVgv/WEjAJrqV4LI6N?=
 =?us-ascii?Q?xlwI+uUFW6OgOSxQNy14Z81fQ+iNIQEdd9raqUwkprl+ZgRI2Dm6bFhj+Kgt?=
 =?us-ascii?Q?iw=3D=3D?=
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 
	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
X-OriginatorOrg: oracle.com
X-MS-Exchange-CrossTenant-Network-Message-Id: 828b5498-a7bc-47f0-5333-08dc2c58991b
X-MS-Exchange-CrossTenant-AuthSource: CO6PR10MB5409.namprd10.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 13 Feb 2024 05:57:01.8305
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: KfkWEoOpRn+l9IyvJDd8MZvom6wQPYlSL2X1xcmZGbSBfhSbsHxa3JAzI38lR4fsa+o5/jdbj7ZbNFNHKDNIqDpho0FfmM7c/ha9t5XdPXQ=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY8PR10MB6906
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.272,Aquarius:18.0.1011,Hydra:6.0.619,FMLib:17.11.176.26
 definitions=2024-02-13_02,2024-02-12_03,2023-05-22_02
X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 bulkscore=0 suspectscore=0
 phishscore=0 adultscore=0 spamscore=0 mlxlogscore=999 malwarescore=0
 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311290000
 definitions=main-2402130043
X-Proofpoint-GUID: yD1AjVAKFwJC5zOj-JdfyINs1mc27Kqd
X-Proofpoint-ORIG-GUID: yD1AjVAKFwJC5zOj-JdfyINs1mc27Kqd

Tracing support for TIF_NEED_RESCHED_LAZY.

trace_entry::flags is full, so reuse the TRACE_FLAG_IRQS_NOSUPPORT
bit for this. The flag is safe to reuse since it is only used in
old archs that don't support lockdep irq tracing.

Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Originally-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/lkml/87jzshhexi.ffs@tglx/
Signed-off-by: Ankur Arora <ankur.a.arora@oracle.com>
---
 include/linux/trace_events.h |  6 +++---
 kernel/trace/trace.c         |  2 ++
 kernel/trace/trace_output.c  | 16 ++++++++++++++--
 3 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index d68ff9b1247f..0c17e9de1434 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -178,7 +178,7 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status);
 
 enum trace_flag_type {
 	TRACE_FLAG_IRQS_OFF		= 0x01,
-	TRACE_FLAG_IRQS_NOSUPPORT	= 0x02,
+	TRACE_FLAG_NEED_RESCHED_LAZY    = 0x02,
 	TRACE_FLAG_NEED_RESCHED		= 0x04,
 	TRACE_FLAG_HARDIRQ		= 0x08,
 	TRACE_FLAG_SOFTIRQ		= 0x10,
@@ -205,11 +205,11 @@ static inline unsigned int tracing_gen_ctx(void)
 
 static inline unsigned int tracing_gen_ctx_flags(unsigned long irqflags)
 {
-	return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+	return tracing_gen_ctx_irq_test(0);
 }
 static inline unsigned int tracing_gen_ctx(void)
 {
-	return tracing_gen_ctx_irq_test(TRACE_FLAG_IRQS_NOSUPPORT);
+	return tracing_gen_ctx_irq_test(0);
 }
 #endif
 
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 0a9642fba852..8fb3a79771df 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2703,6 +2703,8 @@ unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status)
 
 	if (tif_need_resched(NR_now))
 		trace_flags |= TRACE_FLAG_NEED_RESCHED;
+	if (tif_need_resched(NR_lazy))
+		trace_flags |= TRACE_FLAG_NEED_RESCHED_LAZY;
 	if (test_preempt_need_resched())
 		trace_flags |= TRACE_FLAG_PREEMPT_RESCHED;
 	return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) |
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index 3e7fa44dc2b2..5e120c2404cf 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -460,17 +460,29 @@ int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
 		(entry->flags & TRACE_FLAG_IRQS_OFF && bh_off) ? 'D' :
 		(entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
 		bh_off ? 'b' :
-		(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
+		!IS_ENABLED(CONFIG_TRACE_IRQFLAGS_SUPPORT) ? 'X' :
 		'.';
 
-	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
+	switch (entry->flags & (TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY |
 				TRACE_FLAG_PREEMPT_RESCHED)) {
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'B';
+		break;
 	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'N';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY | TRACE_FLAG_PREEMPT_RESCHED:
+		need_resched = 'L';
+		break;
+	case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'b';
+		break;
 	case TRACE_FLAG_NEED_RESCHED:
 		need_resched = 'n';
 		break;
+	case TRACE_FLAG_NEED_RESCHED_LAZY:
+		need_resched = 'l';
+		break;
 	case TRACE_FLAG_PREEMPT_RESCHED:
 		need_resched = 'p';
 		break;
-- 
2.31.1