[v1] Simplify, reorganize and clean up the x86 text-patching code (alternative.c)

Expand all Fold all

[PATCH 39/53] x86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish() and smp_text_poke_batch_flush() to smp_text_poke_batch_process()

Posted by Ingo Molnar 8 months, 1 week ago

Simplifies the code and improves code generation a bit:

   text	   data	    bss	    dec	    hex	filename
  14769	   1017	   4112	  19898	   4dba	alternative.o.before
  14742	   1017	   4112	  19871	   4d9f	alternative.o.after

Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/kernel/alternative.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index b47ad0853589..556a82f576cd 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2750,6 +2750,9 @@ static void smp_text_poke_batch_process(void)
 		if (unlikely(!atomic_dec_and_test(refs)))
 			atomic_cond_read_acquire(refs, !VAL);
 	}
+
+	/* They are all completed: */
+	text_poke_array.nr_entries = 0;
 }
 
 static void __smp_text_poke_batch_add(void *addr, const void *opcode, size_t len, const void *emulate)
@@ -2857,20 +2860,16 @@ static bool text_poke_addr_ordered(void *addr)
 
 void smp_text_poke_batch_finish(void)
 {
-	if (text_poke_array.nr_entries) {
+	if (text_poke_array.nr_entries)
 		smp_text_poke_batch_process();
-		text_poke_array.nr_entries = 0;
-	}
 }
 
 static void smp_text_poke_batch_flush(void *addr)
 {
 	lockdep_assert_held(&text_mutex);
 
-	if (text_poke_array.nr_entries == TP_ARRAY_NR_ENTRIES_MAX || !text_poke_addr_ordered(addr)) {
+	if (text_poke_array.nr_entries == TP_ARRAY_NR_ENTRIES_MAX || !text_poke_addr_ordered(addr))
 		smp_text_poke_batch_process();
-		text_poke_array.nr_entries = 0;
-	}
 }
 
 /**
-- 
2.45.2

[tip: x86/alternatives] x86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish() and smp_text_poke_batch_flush() to smp_text_poke_batch_process()

Posted by tip-bot2 for Ingo Molnar 8 months, 1 week ago

The following commit has been merged into the x86/alternatives branch of tip:

Commit-ID:     7fbadb50d95a8bbc0de720e0857c77d4f13ddcaf
Gitweb:        https://git.kernel.org/tip/7fbadb50d95a8bbc0de720e0857c77d4f13ddcaf
Author:        Ingo Molnar <mingo@kernel.org>
AuthorDate:    Fri, 11 Apr 2025 07:40:51 +02:00
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Fri, 11 Apr 2025 11:01:34 +02:00

x86/alternatives: Move text_poke_array completion from smp_text_poke_batch_finish() and smp_text_poke_batch_flush() to smp_text_poke_batch_process()

Simplifies the code and improves code generation a bit:

   text	   data	    bss	    dec	    hex	filename
  14769	   1017	   4112	  19898	   4dba	alternative.o.before
  14742	   1017	   4112	  19871	   4d9f	alternative.o.after

Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juergen Gross <jgross@suse.com>
Cc: "H . Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250411054105.2341982-40-mingo@kernel.org
---
 arch/x86/kernel/alternative.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/alternative.c b/arch/x86/kernel/alternative.c
index b47ad08..556a82f 100644
--- a/arch/x86/kernel/alternative.c
+++ b/arch/x86/kernel/alternative.c
@@ -2750,6 +2750,9 @@ static void smp_text_poke_batch_process(void)
 		if (unlikely(!atomic_dec_and_test(refs)))
 			atomic_cond_read_acquire(refs, !VAL);
 	}
+
+	/* They are all completed: */
+	text_poke_array.nr_entries = 0;
 }
 
 static void __smp_text_poke_batch_add(void *addr, const void *opcode, size_t len, const void *emulate)
@@ -2857,20 +2860,16 @@ static bool text_poke_addr_ordered(void *addr)
 
 void smp_text_poke_batch_finish(void)
 {
-	if (text_poke_array.nr_entries) {
+	if (text_poke_array.nr_entries)
 		smp_text_poke_batch_process();
-		text_poke_array.nr_entries = 0;
-	}
 }
 
 static void smp_text_poke_batch_flush(void *addr)
 {
 	lockdep_assert_held(&text_mutex);
 
-	if (text_poke_array.nr_entries == TP_ARRAY_NR_ENTRIES_MAX || !text_poke_addr_ordered(addr)) {
+	if (text_poke_array.nr_entries == TP_ARRAY_NR_ENTRIES_MAX || !text_poke_addr_ordered(addr))
 		smp_text_poke_batch_process();
-		text_poke_array.nr_entries = 0;
-	}
 }
 
 /**