On Fri, Aug 9, 2024 at 5:57 PM Charlie Jenkins <charlie@xxxxxxxxxxxx> wrote: > > On Fri, Aug 09, 2024 at 02:44:44PM -0700, Evan Green wrote: > > In preparation for misaligned vector performance hwprobe keys, rename > > the hwprobe key values associated with misaligned scalar accesses to > > include the term SCALAR. Leave the old defines in place to maintain > > source compatibility. > > > > This change is intended to be a functional no-op. > > > > Signed-off-by: Evan Green <evan@xxxxxxxxxxxx> > > Reviewed-by: Charlie Jenkins <charlie@xxxxxxxxxxxx> > > > > --- > > > > Changes in v4: > > - Add the word scalar (Charlie) > > > > Changes in v3: > > - Leave the old defines in place (Conor, Palmer) > > > > Changes in v2: > > - Added patch to rename misaligned perf key values (Palmer) > > > > Documentation/arch/riscv/hwprobe.rst | 28 ++++++++++++---------- > > arch/riscv/include/uapi/asm/hwprobe.h | 5 ++++ > > arch/riscv/kernel/sys_hwprobe.c | 10 ++++---- > > arch/riscv/kernel/traps_misaligned.c | 6 ++--- > > arch/riscv/kernel/unaligned_access_speed.c | 12 +++++----- > > 5 files changed, 34 insertions(+), 27 deletions(-) > > > > diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst > > index a994eed75bde..85b709257918 100644 > > --- a/Documentation/arch/riscv/hwprobe.rst > > +++ b/Documentation/arch/riscv/hwprobe.rst > > @@ -247,23 +247,25 @@ The following keys are defined: > > the performance of misaligned scalar native word accesses on the selected set > > of processors. > > > > - * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNKNOWN`: The performance of misaligned > > - accesses is unknown. > > + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN`: The performance of > > + misaligned scalar accesses is unknown. > > + enh <enh@xxxxxxxxxx> > > Thanks for respinning this Evan! With this wording change the patch that > changes the wording but not the macro [1] is no longer needed. yeah, this is much better. thanks! > - Charlie > > Link: > https://lore.kernel.org/linux-riscv/CAJgzZorn5anPH8dVPqvjVWmLKqTi5bkLDR=FH-ZAcdXFnNe8Eg@xxxxxxxxxxxxxx/ > [1] > > > > > - * :c:macro:`RISCV_HWPROBE_MISALIGNED_EMULATED`: Misaligned accesses are > > - emulated via software, either in or below the kernel. These accesses are > > - always extremely slow. > > + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED`: Misaligned scalar > > + accesses are emulated via software, either in or below the kernel. These > > + accesses are always extremely slow. > > > > - * :c:macro:`RISCV_HWPROBE_MISALIGNED_SLOW`: Misaligned native word > > - sized accesses are slower than the equivalent quantity of byte accesses. > > - Misaligned accesses may be supported directly in hardware, or trapped and > > - emulated by software. > > + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW`: Misaligned scalar native > > + word sized accesses are slower than the equivalent quantity of byte > > + accesses. Misaligned accesses may be supported directly in hardware, or > > + trapped and emulated by software. > > > > - * :c:macro:`RISCV_HWPROBE_MISALIGNED_FAST`: Misaligned native word > > - sized accesses are faster than the equivalent quantity of byte accesses. > > + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_FAST`: Misaligned scalar native > > + word sized accesses are faster than the equivalent quantity of byte > > + accesses. > > > > - * :c:macro:`RISCV_HWPROBE_MISALIGNED_UNSUPPORTED`: Misaligned accesses are > > - not supported at all and will generate a misaligned address fault. > > + * :c:macro:`RISCV_HWPROBE_MISALIGNED_SCALAR_UNSUPPORTED`: Misaligned scalar > > + accesses are not supported at all and will generate a misaligned address > > + fault. > > > > * :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which > > represents the size of the Zicboz block in bytes. > > diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h > > index 635753084275..1e153cda57db 100644 > > --- a/arch/riscv/include/uapi/asm/hwprobe.h > > +++ b/arch/riscv/include/uapi/asm/hwprobe.h > > @@ -83,6 +83,11 @@ struct riscv_hwprobe { > > #define RISCV_HWPROBE_KEY_HIGHEST_VIRT_ADDRESS 7 > > #define RISCV_HWPROBE_KEY_TIME_CSR_FREQ 8 > > #define RISCV_HWPROBE_KEY_MISALIGNED_SCALAR_PERF 9 > > +#define RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN 0 > > +#define RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED 1 > > +#define RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW 2 > > +#define RISCV_HWPROBE_MISALIGNED_SCALAR_FAST 3 > > +#define RISCV_HWPROBE_MISALIGNED_SCALAR_UNSUPPORTED 4 > > /* Increase RISCV_HWPROBE_MAX_KEY when adding items. */ > > > > /* Flags */ > > diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c > > index 2d0f4f6a32c3..cea0ca2bf2a2 100644 > > --- a/arch/riscv/kernel/sys_hwprobe.c > > +++ b/arch/riscv/kernel/sys_hwprobe.c > > @@ -178,13 +178,13 @@ static u64 hwprobe_misaligned(const struct cpumask *cpus) > > perf = this_perf; > > > > if (perf != this_perf) { > > - perf = RISCV_HWPROBE_MISALIGNED_UNKNOWN; > > + perf = RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN; > > break; > > } > > } > > > > if (perf == -1ULL) > > - return RISCV_HWPROBE_MISALIGNED_UNKNOWN; > > + return RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN; > > > > return perf; > > } > > @@ -192,12 +192,12 @@ static u64 hwprobe_misaligned(const struct cpumask *cpus) > > static u64 hwprobe_misaligned(const struct cpumask *cpus) > > { > > if (IS_ENABLED(CONFIG_RISCV_EFFICIENT_UNALIGNED_ACCESS)) > > - return RISCV_HWPROBE_MISALIGNED_FAST; > > + return RISCV_HWPROBE_MISALIGNED_SCALAR_FAST; > > > > if (IS_ENABLED(CONFIG_RISCV_EMULATED_UNALIGNED_ACCESS) && unaligned_ctl_available()) > > - return RISCV_HWPROBE_MISALIGNED_EMULATED; > > + return RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED; > > > > - return RISCV_HWPROBE_MISALIGNED_SLOW; > > + return RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW; > > } > > #endif > > > > diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c > > index b62d5a2f4541..192cd5603e95 100644 > > --- a/arch/riscv/kernel/traps_misaligned.c > > +++ b/arch/riscv/kernel/traps_misaligned.c > > @@ -338,7 +338,7 @@ int handle_misaligned_load(struct pt_regs *regs) > > perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1, regs, addr); > > > > #ifdef CONFIG_RISCV_PROBE_UNALIGNED_ACCESS > > - *this_cpu_ptr(&misaligned_access_speed) = RISCV_HWPROBE_MISALIGNED_EMULATED; > > + *this_cpu_ptr(&misaligned_access_speed) = RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED; > > #endif > > > > if (!unaligned_enabled) > > @@ -532,13 +532,13 @@ static bool check_unaligned_access_emulated(int cpu) > > unsigned long tmp_var, tmp_val; > > bool misaligned_emu_detected; > > > > - *mas_ptr = RISCV_HWPROBE_MISALIGNED_UNKNOWN; > > + *mas_ptr = RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN; > > > > __asm__ __volatile__ ( > > " "REG_L" %[tmp], 1(%[ptr])\n" > > : [tmp] "=r" (tmp_val) : [ptr] "r" (&tmp_var) : "memory"); > > > > - misaligned_emu_detected = (*mas_ptr == RISCV_HWPROBE_MISALIGNED_EMULATED); > > + misaligned_emu_detected = (*mas_ptr == RISCV_HWPROBE_MISALIGNED_SCALAR_EMULATED); > > /* > > * If unaligned_ctl is already set, this means that we detected that all > > * CPUS uses emulated misaligned access at boot time. If that changed > > diff --git a/arch/riscv/kernel/unaligned_access_speed.c b/arch/riscv/kernel/unaligned_access_speed.c > > index a9a6bcb02acf..160628a2116d 100644 > > --- a/arch/riscv/kernel/unaligned_access_speed.c > > +++ b/arch/riscv/kernel/unaligned_access_speed.c > > @@ -34,9 +34,9 @@ static int check_unaligned_access(void *param) > > struct page *page = param; > > void *dst; > > void *src; > > - long speed = RISCV_HWPROBE_MISALIGNED_SLOW; > > + long speed = RISCV_HWPROBE_MISALIGNED_SCALAR_SLOW; > > > > - if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_UNKNOWN) > > + if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN) > > return 0; > > > > /* Make an unaligned destination buffer. */ > > @@ -95,14 +95,14 @@ static int check_unaligned_access(void *param) > > } > > > > if (word_cycles < byte_cycles) > > - speed = RISCV_HWPROBE_MISALIGNED_FAST; > > + speed = RISCV_HWPROBE_MISALIGNED_SCALAR_FAST; > > > > ratio = div_u64((byte_cycles * 100), word_cycles); > > pr_info("cpu%d: Ratio of byte access time to unaligned word access is %d.%02d, unaligned accesses are %s\n", > > cpu, > > ratio / 100, > > ratio % 100, > > - (speed == RISCV_HWPROBE_MISALIGNED_FAST) ? "fast" : "slow"); > > + (speed == RISCV_HWPROBE_MISALIGNED_SCALAR_FAST) ? "fast" : "slow"); > > > > per_cpu(misaligned_access_speed, cpu) = speed; > > > > @@ -110,7 +110,7 @@ static int check_unaligned_access(void *param) > > * Set the value of fast_misaligned_access of a CPU. These operations > > * are atomic to avoid race conditions. > > */ > > - if (speed == RISCV_HWPROBE_MISALIGNED_FAST) > > + if (speed == RISCV_HWPROBE_MISALIGNED_SCALAR_FAST) > > cpumask_set_cpu(cpu, &fast_misaligned_access); > > else > > cpumask_clear_cpu(cpu, &fast_misaligned_access); > > @@ -188,7 +188,7 @@ static int riscv_online_cpu(unsigned int cpu) > > static struct page *buf; > > > > /* We are already set since the last check */ > > - if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_UNKNOWN) > > + if (per_cpu(misaligned_access_speed, cpu) != RISCV_HWPROBE_MISALIGNED_SCALAR_UNKNOWN) > > goto exit; > > > > buf = alloc_pages(GFP_KERNEL, MISALIGNED_BUFFER_ORDER); > > -- > > 2.34.1 > >
