Re: [PATCH v3 21/21] sparc64: use match_string() helper

From: Andy Shevchenko
Date: Wed Jun 06 2018 - 01:02:00 EST


On Wed, Jun 6, 2018 at 5:19 AM, Yisheng Xie <xieyisheng1@xxxxxxxxxx> wrote:
> match_string() returns the index of an array for a matching string,
> which can be used instead of open coded variant.
>

Thanks for an update.
My comments below.

I think you need to mentioned the string literal change in the commit message.

> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> Cc: Anthony Yznaga <anthony.yznaga@xxxxxxxxxx>
> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx>
> Cc: sparclinux@xxxxxxxxxxxxxxx
> Signed-off-by: Yisheng Xie <xieyisheng1@xxxxxxxxxx>
> ---
> v3:
> - add string literal instead of NULL for array hwcaps to make it
> can use match_string() too. - per Andy
> v2
> - new add for use match_string() helper patchset.
>
> arch/sparc/kernel/setup_64.c | 23 +++++++++--------------
> 1 file changed, 9 insertions(+), 14 deletions(-)
>
> diff --git a/arch/sparc/kernel/setup_64.c b/arch/sparc/kernel/setup_64.c
> index 7944b3c..4f0ec0c 100644
> --- a/arch/sparc/kernel/setup_64.c
> +++ b/arch/sparc/kernel/setup_64.c
> @@ -401,7 +401,7 @@ void __init start_early_boot(void)
> */
> "mul32", "div32", "fsmuld", "v8plus", "popc", "vis", "vis2",
> "ASIBlkInit", "fmaf", "vis3", "hpc", "random", "trans", "fjfmau",
> - "ima", "cspare", "pause", "cbcond", NULL /*reserved for crypto */,
> + "ima", "cspare", "pause", "cbcond", "resv" /*reserved for crypto */,
> "adp",

Why not to spell "crypto" explicitly and remove comment?

> };
>
> @@ -418,7 +418,7 @@ void cpucap_info(struct seq_file *m)
> seq_puts(m, "cpucaps\t\t: ");
> for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
> unsigned long bit = 1UL << i;
> - if (hwcaps[i] && (caps & bit)) {
> + if (bit != HWCAP_SPARC_CRYPTO && (caps & bit)) {

I would rather swap the order of subsonditions to check if caps has a
bit first, and then exclude CRYPTO.

> seq_printf(m, "%s%s",
> printed ? "," : "", hwcaps[i]);
> printed++;
> @@ -472,7 +472,7 @@ static void __init report_hwcaps(unsigned long caps)
>
> for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
> unsigned long bit = 1UL << i;
> - if (hwcaps[i] && (caps & bit))
> + if (bit != HWCAP_SPARC_CRYPTO && (caps & bit))
> report_one_hwcap(&printed, hwcaps[i]);

Ditto.

> }
> if (caps & HWCAP_SPARC_CRYPTO)
> @@ -504,18 +504,13 @@ static unsigned long __init mdesc_cpu_hwcap_list(void)
> while (len) {
> int i, plen;
>
> - for (i = 0; i < ARRAY_SIZE(hwcaps); i++) {
> - unsigned long bit = 1UL << i;
> + i = match_string(hwcaps, ARRAY_SIZE(hwcaps), prop);
> + if (i >= 0)
> + caps |= (1UL << i);

Parens are redundant (and actually didn't present in the original code above).

>
> - if (hwcaps[i] && !strcmp(prop, hwcaps[i])) {
> - caps |= bit;
> - break;
> - }
> - }
> - for (i = 0; i < ARRAY_SIZE(crypto_hwcaps); i++) {
> - if (!strcmp(prop, crypto_hwcaps[i]))
> - caps |= HWCAP_SPARC_CRYPTO;
> - }
> + i = match_string(crypto_hwcaps, ARRAY_SIZE(crypto_hwcaps), prop);
> + if (i >= 0)
> + caps |= HWCAP_SPARC_CRYPTO;
>
> plen = strlen(prop) + 1;
> prop += plen;
> --
> 1.7.12.4
>
>
>



--
With Best Regards,
Andy Shevchenko