Unverified Commit 652b56b1 authored by Samuel Holland's avatar Samuel Holland Committed by Palmer Dabbelt
Browse files

riscv: jump_label: Batch icache maintenance 



Switch to the batched version of the jump label update functions so
instruction cache maintenance is deferred until the end of the update.

Reviewed-by: default avatarBjörn Töpel <bjorn@rivosinc.com>
Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Link: https://lore.kernel.org/r/20240327160520.791322-2-samuel.holland@sifive.com


Signed-off-by: default avatarPalmer Dabbelt <palmer@rivosinc.com>
parent 1613e604

arch/riscv/include/asm/jump_label.h

+2 −0
Original line number Diff line number Diff line
@@ -12,6 +12,8 @@ 
#include <linux/types.h>

#include <asm/asm.h>



#define HAVE_JUMP_LABEL_BATCH



#define JUMP_LABEL_NOP_SIZE 4



static __always_inline bool arch_static_branch(struct static_key * const key,

arch/riscv/kernel/jump_label.c

+12 −4
Original line number Diff line number Diff line
@@ -9,12 +9,13 @@ 
#include <linux/memory.h>

#include <linux/mutex.h>

#include <asm/bug.h>

#include <asm/cacheflush.h>

#include <asm/patch.h>



#define RISCV_INSN_NOP 0x00000013U

#define RISCV_INSN_JAL 0x0000006fU



void arch_jump_label_transform(struct jump_entry *entry,

bool arch_jump_label_transform_queue(struct jump_entry *entry,

				     enum jump_label_type type)

{

	void *addr = (void *)jump_entry_code(entry);
@@ -24,7 +25,7 @@ void arch_jump_label_transform(struct jump_entry *entry, 
		long offset = jump_entry_target(entry) - jump_entry_code(entry);



		if (WARN_ON(offset & 1 || offset < -524288 || offset >= 524288))

			return;

			return true;



		insn = RISCV_INSN_JAL |

			(((u32)offset & GENMASK(19, 12)) << (12 - 12)) |
@@ -36,6 +37,13 @@ void arch_jump_label_transform(struct jump_entry *entry, 
	}



	mutex_lock(&text_mutex);

	patch_text_nosync(addr, &insn, sizeof(insn));

	patch_insn_write(addr, &insn, sizeof(insn));

	mutex_unlock(&text_mutex);



	return true;

}



void arch_jump_label_transform_apply(void)

{

	flush_icache_all();

}