Re: [PATCH 2/7] kernel: cobalt: fix build with kernel v4.20

[Jan Kiszka <jan.kiszka@siemens.com>]

On 05.03.19 15:45, roman.stratiienko--- via Xenomai wrote:
> From: Roman Stratiienko <roman.stratiienko@globallogic.com>
> 
> READ_ONCE() introduced from v3.19 commit 230fa253df63
> ("kernel: Provide READ_ONCE and ASSIGN_ONCE")
> and ACCESS_ONCE() removed startibg from v4.15-rc4 commit
> b899a850431e ("compiler.h: Remove ACCESS_ONCE()")
> Replace ACCESS_ONCE with READ_ONCE and make READ_ONCE wrapper
> for case when READ_ONCE is not available (<v3.19)
> 
> print_symbol() removed since v4.16-rc1 commit d2279c9d7f7d
> ("kallsyms: remove print_symbol() function")
> use print_symbol for version less than v4.16 and printk starting from v4.16
> 
> $SRCARCH removed since v4.18-rc1, upstream commit 104daea149c4
> ("kconfig: reference environment variables directly and remove 'option env='")
> forward SRCARCH from the scripts/prepare-kernel.sh
> 
> siginfo_t can't be used in kernel-space starting from v4.20-rc1 commit
> ae7795bc6187 ("signal: Distinguish between kernel_siginfo and siginfo")
> replace all siginfo_t to kernel_siginfo_t and create wrapper for kernel < v4.20
> 

Could you split this up so that we have a clearer correlation between a related 
subject, log message and code changes?

> Signed-off-by: Roman Stratiienko <roman.stratiienko@globallogic.com>
> ---
>   include/cobalt/uapi/kernel/urw.h               | 6 +++++-
>   kernel/cobalt/include/linux/xenomai/wrappers.h | 4 ++++
>   kernel/cobalt/posix/process.c                  | 6 +++++-
>   kernel/cobalt/thread.c                         | 4 ++--
>   scripts/Kconfig.frag                           | 2 +-
>   scripts/prepare-kernel.sh                      | 1 +
>   6 files changed, 18 insertions(+), 5 deletions(-)
> 
> diff --git a/include/cobalt/uapi/kernel/urw.h b/include/cobalt/uapi/kernel/urw.h
> index 40a1eb5ff..fcfde21a0 100644
> --- a/include/cobalt/uapi/kernel/urw.h
> +++ b/include/cobalt/uapi/kernel/urw.h
> @@ -53,11 +53,15 @@ typedef struct {
>   #define URW_INITIALIZER     { 0 }
>   #define DEFINE_URW(__name)  urw_t __name = URW_INITIALIZER
>   
> +#ifndef READ_ONCE
> +#define READ_ONCE ACCESS_ONCE
> +#endif
> +
>   static inline void __try_read_start(const urw_t *urw, urwstate_t *tmp)
>   {
>   	__u32 token;
>   repeat:
> -	token = ACCESS_ONCE(urw->sequence);
> +	token = READ_ONCE(urw->sequence);
>   	smp_rmb();
>   	if (token & 1) {
>   		cpu_relax();
> diff --git a/kernel/cobalt/include/linux/xenomai/wrappers.h b/kernel/cobalt/include/linux/xenomai/wrappers.h
> index 7d00aa9d4..6ea86a0fd 100644
> --- a/kernel/cobalt/include/linux/xenomai/wrappers.h
> +++ b/kernel/cobalt/include/linux/xenomai/wrappers.h
> @@ -49,4 +49,8 @@
>   #define ipipe_root_nr_syscalls(ti)	NR_syscalls
>   #endif
>   
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(4,20,0)
> +typedef siginfo_t kernel_siginfo_t;
> +#endif
> +
>   #endif /* !_COBALT_LINUX_WRAPPERS_H */
> diff --git a/kernel/cobalt/posix/process.c b/kernel/cobalt/posix/process.c
> index d0f2f3725..dcf6234d3 100644
> --- a/kernel/cobalt/posix/process.c
> +++ b/kernel/cobalt/posix/process.c
> @@ -583,7 +583,7 @@ static inline void clear_threadinfo(void)
>   static inline int disable_ondemand_memory(void)
>   {
>   	struct task_struct *p = current;
> -	siginfo_t si;
> +	kernel_siginfo_t si;
>   
>   	if ((p->mm->def_flags & VM_LOCKED) == 0) {
>   		memset(&si, 0, sizeof(si));
> @@ -747,7 +747,11 @@ static inline int handle_exception(struct ipipe_trap_data *d)
>   		}
>   		splexit(s);
>   #endif /* CONFIG_XENO_ARCH_FPU */
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 16, 0)
> +		printk("invalid use of FPU in Xenomai context at %pS\n",
> +#else
>   		print_symbol("invalid use of FPU in Xenomai context at %s\n",
> +#endif
>   			     xnarch_fault_pc(d));
>   	}
>   
> diff --git a/kernel/cobalt/thread.c b/kernel/cobalt/thread.c
> index a43d2f1ad..fa7a65569 100644
> --- a/kernel/cobalt/thread.c
> +++ b/kernel/cobalt/thread.c
> @@ -2070,7 +2070,7 @@ void xnthread_relax(int notify, int reason)
>   	struct xnthread *thread = xnthread_current();
>   	struct task_struct *p = current;
>   	int cpu __maybe_unused;
> -	siginfo_t si;
> +	kernel_siginfo_t si;
>   
>   	primary_mode_only();
>   
> @@ -2183,7 +2183,7 @@ static void lostage_task_signal(struct ipipe_work_header *work)
>   	struct lostage_signal *rq;
>   	struct xnthread *thread;
>   	struct task_struct *p;
> -	siginfo_t si;
> +	kernel_siginfo_t si;
>   	int signo;
>   
>   	rq = container_of(work, struct lostage_signal, work);
> diff --git a/scripts/Kconfig.frag b/scripts/Kconfig.frag
> index cd39f7670..c9655d43a 100644
> --- a/scripts/Kconfig.frag
> +++ b/scripts/Kconfig.frag
> @@ -16,7 +16,7 @@ menuconfig XENOMAI
>   	  Please visit http://xenomai.org for more information.
>   
>   if XENOMAI
> -source "arch/$SRCARCH/xenomai/Kconfig"
> +source "arch/@SRCARCH@/xenomai/Kconfig"
>   endif
>   
>   if MIGRATION
> diff --git a/scripts/prepare-kernel.sh b/scripts/prepare-kernel.sh
> index 964e42e83..8707b1198 100755
> --- a/scripts/prepare-kernel.sh
> +++ b/scripts/prepare-kernel.sh
> @@ -376,6 +376,7 @@ case $linux_VERSION.$linux_PATCHLEVEL in
>   	    -e "s,@VERSION_MINOR@,$version_minor,g" \
>   	    -e "s,@REVISION_LEVEL@,$revision_level,g" \
>   	    -e "s,@VERSION_STRING@,$version_string,g" \
> +	    -e "s,@SRCARCH@,$linux_arch,g" \
>   	    $xenomai_root/scripts/Kconfig.frag |
>               patch_append init/Kconfig
>       fi
> 

Looks good otherwise.

Jan

-- 
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