Re: [PATCH v6] lib/eal/ppc fix compilation for musl

[Dunk <dunk@denkimushi.com>]

> On 9 May 2022, at 13:06, David Marchand <david.marchand@redhat.com> wrote:
> 
> On Sat, May 7, 2022 at 11:16 PM Duncan Bellamy <dunk@denkimushi.com> wrote:
>> 
>> musl lacks __ppc_get_timebase() but has __builtin_ppc_get_timebase()
>> 
>> the __ppc_get_timebase_freq() is taken from:
>> https://git.alpinelinux.org/aports/commit/?id=06b03f70fb94972286c0c9f6278df89e53903833
>> 
>> Signed-off-by: Duncan Bellamy <dunk@denkimushi.com>
> 
> - A patch title does not need lib/ prefix.
> Here, "eal/ppc: " is enough.
> 
> 
> - Code in lib/eal/linux won't be used for FreeBSD/Windows.
> On the other hand, arch-specific code (here, lib/eal/ppc/) can be used
> for the various OS.
> Besides, as far as I can see in the Linux kernel sources, powerpc is
> the only architecture that exports a "timebase" entry in
> /proc/cpuinfo.
> So, I see no reason to put any code out of lib/eal/ppc.
> 
> 
> - In the end, unless I missed some point, the patch could probably
> look like (untested):
> 
> diff --git a/lib/eal/ppc/include/rte_cycles.h b/lib/eal/ppc/include/rte_cycles.h
> index 5585f9273c..666fc9b0bf 100644
> --- a/lib/eal/ppc/include/rte_cycles.h
> +++ b/lib/eal/ppc/include/rte_cycles.h
> @@ -10,7 +10,10 @@
> extern "C" {
> #endif
> 
> +#include <features.h>
> +#ifdef __GLIBC__
> #include <sys/platform/ppc.h>
> +#endif
> 
> #include "generic/rte_cycles.h"
> 
> @@ -26,7 +29,11 @@ extern "C" {
> static inline uint64_t
> rte_rdtsc(void)
> {
> +#ifdef __GLIBC__
>        return __ppc_get_timebase();
> +#else
> +       return __builtin_ppc_get_timebase();
> +#endif
> }
> 
> static inline uint64_t
> diff --git a/lib/eal/ppc/rte_cycles.c b/lib/eal/ppc/rte_cycles.c
> index 3180adb0ff..99d36b2f7e 100644
> --- a/lib/eal/ppc/rte_cycles.c
> +++ b/lib/eal/ppc/rte_cycles.c
> @@ -2,12 +2,50 @@
>  * Copyright (C) IBM Corporation 2019.
>  */
> 
> +#include <features.h>
> +#ifdef __GLIBC__
> #include <sys/platform/ppc.h>
> +#elif RTE_EXEC_ENV_LINUX
> +#include <string.h>
> +#include <stdio.h>
> +#endif
> 
> #include "eal_private.h"
> 
> uint64_t
> get_tsc_freq_arch(void)
> {
> +#ifdef __GLIBC__
>        return __ppc_get_timebase_freq();
> +#elif RTE_EXEC_ENV_LINUX
> +       static unsigned long base;
> +       char buf[512];
> +       ssize_t nr;
> +       FILE *f;
> +
> +       if (base != 0)
> +               goto out;
> +
> +       f = fopen("/proc/cpuinfo", "rb");
> +       if (f == NULL)
> +               goto out;
> +
> +       while (fgets(buf, sizeof(buf), f) != NULL) {
> +               char *ret = strstr(buf, "timebase");
> +
> +               if (ret == NULL)
> +                       continue;
> +               ret += sizeof("timebase") - 1;
> +               ret = strchr(ret, ':');
> +               if (ret == NULL)
> +                       continue;
> +               base = strtoul(ret + 1, NULL, 10);
> +               break;
> +       }
> +       fclose(f);
> +out:
> +       return (uint64_t) base;
> +#else
> +       return 0;
> +#endif
> }
> 
> 
> -- 
> David Marchand
> 

Thanks, that looks the same thing.  Will run through alpine CI and change commit title