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From: Daniel Bristot de Oliveira <bristot@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Pavel Tatashin <pasha.tatashin@oracle.com>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	"Steven Rostedt (VMware)" <rostedt@goodmis.org>,
	Zhou Chengming <zhouchengming1@huawei.com>,
	Jiri Kosina <jkosina@suse.cz>,
	Josh Poimboeuf <jpoimboe@redhat.com>,
	"Peter Zijlstra (Intel)" <peterz@infradead.org>,
	Chris von Recklinghausen <crecklin@redhat.com>,
	Jason Baron <jbaron@akamai.com>, Scott Wood <swood@redhat.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	Clark Williams <williams@redhat.com>,
	x86@kernel.org
Subject: [PATCH V2 4/9] x86/jump_label: Add __jump_label_set_jump_code() helper
Date: Tue, 18 Dec 2018 17:46:33 +0100	[thread overview]
Message-ID: <273d912befe0cedc409eb760679d58ee6de94bfc.1545149539.git.bristot@redhat.com> (raw)
In-Reply-To: <cover.1545149539.git.bristot@redhat.com>

Move the definition of the code to be written from
__jump_label_transform() to a specialized function.

Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Zhou Chengming <zhouchengming1@huawei.com>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Chris von Recklinghausen <crecklin@redhat.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Scott Wood <swood@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
---
 arch/x86/kernel/jump_label.c | 38 +++++++++++++++++++++---------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/arch/x86/kernel/jump_label.c b/arch/x86/kernel/jump_label.c
index 7894080bd02f..a039ac4ca5bf 100644
--- a/arch/x86/kernel/jump_label.c
+++ b/arch/x86/kernel/jump_label.c
@@ -75,30 +75,36 @@ static inline void __jump_label_trans_check_disable(struct jump_entry *entry,
 		bug_at((void *)jump_entry_code(entry), line);
 }
 
+static void __jump_label_set_jump_code(struct jump_entry *entry,
+				       enum jump_label_type type,
+				       union jump_code_union *code,
+				       int init)
+{
+	const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
+
+	code->jump = 0xe9;
+	code->offset = jump_entry_target(entry) -
+		     (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
+
+	if (type == JUMP_LABEL_JMP) {
+		__jump_label_trans_check_enable(entry, type, ideal_nop, init);
+	} else {
+		__jump_label_trans_check_disable(entry, type, code, init);
+		memcpy(code, ideal_nop, JUMP_LABEL_NOP_SIZE);
+	}
+}
 
 static void __ref __jump_label_transform(struct jump_entry *entry,
 					 enum jump_label_type type,
 					 void *(*poker)(void *, const void *, size_t),
 					 int init)
 {
-	union jump_code_union jmp;
-	const unsigned char *ideal_nop = ideal_nops[NOP_ATOMIC5];
-	const void *code;
-
-	jmp.jump = 0xe9;
-	jmp.offset = jump_entry_target(entry) -
-		     (jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
+	union jump_code_union code;
 
 	if (early_boot_irqs_disabled)
 		poker = text_poke_early;
 
-	if (type == JUMP_LABEL_JMP) {
-		__jump_label_trans_check_enable(entry, type, ideal_nop, init);
-		code = &jmp.code;
-	} else {
-		__jump_label_trans_check_disable(entry, type, &jmp, init);
-		code = ideal_nop;
-	}
+	__jump_label_set_jump_code(entry, type, &code, init);
 
 	/*
 	 * Make text_poke_bp() a default fallback poker.
@@ -109,12 +115,12 @@ static void __ref __jump_label_transform(struct jump_entry *entry,
 	 *
 	 */
 	if (poker) {
-		(*poker)((void *)jump_entry_code(entry), code,
+		(*poker)((void *)jump_entry_code(entry), &code,
 			 JUMP_LABEL_NOP_SIZE);
 		return;
 	}
 
-	text_poke_bp((void *)jump_entry_code(entry), code, JUMP_LABEL_NOP_SIZE,
+	text_poke_bp((void *)jump_entry_code(entry), &code, JUMP_LABEL_NOP_SIZE,
 		     (void *)jump_entry_code(entry) + JUMP_LABEL_NOP_SIZE);
 }
 
-- 
2.17.1


  parent reply	other threads:[~2018-12-18 16:47 UTC|newest]

Thread overview: 24+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-12-18 16:46 [PATCH V2 0/9] x86/jump_label: Bound IPIs sent when updating a static key Daniel Bristot de Oliveira
2018-12-18 16:46 ` [PATCH V2 1/9] jump_label: Add for_each_label_entry helper Daniel Bristot de Oliveira
2018-12-18 21:19   ` Borislav Petkov
2018-12-19  7:38     ` Daniel Bristot de Oliveira
2018-12-19 10:37       ` Borislav Petkov
2018-12-18 16:46 ` [PATCH V2 2/9] jump_label: Add the jump_label_can_update_check() helper Daniel Bristot de Oliveira
2018-12-18 16:46 ` [PATCH V2 3/9] x86/jump_label: Move checking code away from __jump_label_transform() Daniel Bristot de Oliveira
2018-12-19  8:43   ` Jiri Kosina
2018-12-19  8:49     ` Thomas Gleixner
2018-12-19 10:14       ` Daniel Bristot de Oliveira
2018-12-18 16:46 ` Daniel Bristot de Oliveira [this message]
2018-12-18 16:46 ` [PATCH V2 5/9] x86/alternative: Split text_poke_bp() into tree steps Daniel Bristot de Oliveira
2018-12-18 17:25   ` Steven Rostedt
2018-12-19  8:44   ` Jiri Kosina
2018-12-18 16:46 ` [PATCH V2 6/9] jump_label: Sort entries of the same key by the code Daniel Bristot de Oliveira
2018-12-18 16:46 ` [PATCH V2 7/9] x86/alternative: Batch of patch operations Daniel Bristot de Oliveira
2018-12-18 17:31   ` Steven Rostedt
2018-12-18 19:27     ` Daniel Bristot de Oliveira
2018-12-18 16:46 ` [PATCH V2 8/9] x86/jump_label: Batch jump label updates Daniel Bristot de Oliveira
2018-12-18 16:46 ` [PATCH V2 9/9] jump_label: Batch up if arch supports it Daniel Bristot de Oliveira
2018-12-18 17:35   ` Steven Rostedt
2018-12-18 19:33     ` Daniel Bristot de Oliveira
2018-12-18 20:32       ` Steven Rostedt
2018-12-18 21:06         ` Daniel Bristot de Oliveira

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