diff options
| author | Andy Chiu <andy.chiu@sifive.com> | 2024-01-15 05:59:28 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-01-16 07:14:01 -0800 |
| commit | bd446f5df5afab212917f6732ba6442a5e8de85e (patch) | |
| tree | dce6c1b77b3260997ded34e7e30afc9a16c3d24b /arch/riscv/kernel/vector.c | |
| parent | 5b6048f2ff710196c85ce14373febe8be5115bbe (diff) | |
riscv: vector: use kmem_cache to manage vector context
The allocation size of thread.vstate.datap is always riscv_v_vsize. So
it is possbile to use kmem_cache_* to manage the allocation. This gives
users more information regarding allocation of vector context via
/proc/slabinfo. And it potentially reduces the latency of the first-use
trap because of the allocation caches.
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20240115055929.4736-10-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel/vector.c')
| -rw-r--r-- | arch/riscv/kernel/vector.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c index c1f28bc89ec6..f7b4aeb9e457 100644 --- a/arch/riscv/kernel/vector.c +++ b/arch/riscv/kernel/vector.c @@ -21,6 +21,7 @@ #include <asm/bug.h> static bool riscv_v_implicit_uacc = IS_ENABLED(CONFIG_RISCV_ISA_V_DEFAULT_ENABLE); +static struct kmem_cache *riscv_v_user_cachep; unsigned long riscv_v_vsize __read_mostly; EXPORT_SYMBOL_GPL(riscv_v_vsize); @@ -47,6 +48,16 @@ int riscv_v_setup_vsize(void) return 0; } +void __init riscv_v_setup_ctx_cache(void) +{ + if (!has_vector()) + return; + + riscv_v_user_cachep = kmem_cache_create_usercopy("riscv_vector_ctx", + riscv_v_vsize, 16, SLAB_PANIC, + 0, riscv_v_vsize, NULL); +} + static bool insn_is_vector(u32 insn_buf) { u32 opcode = insn_buf & __INSN_OPCODE_MASK; @@ -84,7 +95,7 @@ static int riscv_v_thread_zalloc(void) { void *datap; - datap = kzalloc(riscv_v_vsize, GFP_KERNEL); + datap = kmem_cache_zalloc(riscv_v_user_cachep, GFP_KERNEL); if (!datap) return -ENOMEM; @@ -94,6 +105,12 @@ static int riscv_v_thread_zalloc(void) return 0; } +void riscv_v_thread_free(struct task_struct *tsk) +{ + if (tsk->thread.vstate.datap) + kmem_cache_free(riscv_v_user_cachep, tsk->thread.vstate.datap); +} + #define VSTATE_CTRL_GET_CUR(x) ((x) & PR_RISCV_V_VSTATE_CTRL_CUR_MASK) #define VSTATE_CTRL_GET_NEXT(x) (((x) & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) >> 2) #define VSTATE_CTRL_MAKE_NEXT(x) (((x) << 2) & PR_RISCV_V_VSTATE_CTRL_NEXT_MASK) |