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| author | Palmer Dabbelt <palmer@rivosinc.com> | 2024-05-16 13:00:00 -0700 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2024-05-16 13:03:57 -0700 |
| commit | 8446d1fcad49929bbea82f2d657272659d6317f6 (patch) | |
| tree | 4ddafb9ccf88390e6b8a6b9467f62a6c93b92da6 | |
| parent | 6d73100b6e90dc214337338d6d4ee4e209e8ad67 (diff) | |
| parent | ad5643cf2f699989daa85d909403febd6712fccb (diff) | |
| download | linux-for-next.tar.gz | |
Merge patch series "riscv: access_ok() optimization"for-next
Samuel Holland <samuel.holland@sifive.com> says:
This series optimizes access_ok() by defining TASK_SIZE_MAX. At Alex's
suggestion, I also tried making TASK_SIZE constant (specifically by
making PGDIR_SHIFT a variable instead of a ternary expression, then
replacing the load with an immediate using ALTERNATIVE). This appeared
to slightly improve performance on some implementations (C906) but
regressed it on others (FU740). So I am leaving further optimizations to
a later series.
* b4-shazam-merge:
riscv: Define TASK_SIZE_MAX for __access_ok()
riscv: Remove PGDIR_SIZE_L3 and TASK_SIZE_MIN
Link: https://lore.kernel.org/r/20240327143858.711792-1-samuel.holland@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
| -rw-r--r-- | arch/riscv/include/asm/pgtable-64.h | 2 | ||||
| -rw-r--r-- | arch/riscv/include/asm/pgtable.h | 3 |
2 files changed, 1 insertions, 4 deletions
diff --git a/arch/riscv/include/asm/pgtable-64.h b/arch/riscv/include/asm/pgtable-64.h index 221a5c1ee287e6..8c36a881843272 100644 --- a/arch/riscv/include/asm/pgtable-64.h +++ b/arch/riscv/include/asm/pgtable-64.h @@ -16,8 +16,6 @@ extern bool pgtable_l5_enabled; #define PGDIR_SHIFT_L3 30 #define PGDIR_SHIFT_L4 39 #define PGDIR_SHIFT_L5 48 -#define PGDIR_SIZE_L3 (_AC(1, UL) << PGDIR_SHIFT_L3) - #define PGDIR_SHIFT (pgtable_l5_enabled ? PGDIR_SHIFT_L5 : \ (pgtable_l4_enabled ? PGDIR_SHIFT_L4 : PGDIR_SHIFT_L3)) /* Size of region mapped by a page global directory */ diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 58fd7b70b90309..08703d99d004a1 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -870,7 +870,7 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) */ #ifdef CONFIG_64BIT #define TASK_SIZE_64 (PGDIR_SIZE * PTRS_PER_PGD / 2) -#define TASK_SIZE_MIN (PGDIR_SIZE_L3 * PTRS_PER_PGD / 2) +#define TASK_SIZE_MAX LONG_MAX #ifdef CONFIG_COMPAT #define TASK_SIZE_32 (_AC(0x80000000, UL) - PAGE_SIZE) @@ -882,7 +882,6 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte) #else #define TASK_SIZE FIXADDR_START -#define TASK_SIZE_MIN TASK_SIZE #endif #else /* CONFIG_MMU */ |