From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Li, Aubrey" Subject: Re: [PATCH v14 1/3] /proc/pid/status: Add support for architecture specific output Date: Wed, 10 Apr 2019 10:36:37 +0800 Message-ID: References: <20190410015326.24500-1-aubrey.li@linux.intel.com> <89957461-ec42-f041-a7e9-2452b2e83d39@linux.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Andy Lutomirski Cc: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , "H. Peter Anvin" , Andi Kleen , Tim Chen , Dave Hansen , Arjan van de Ven , Alexey Dobriyan , Andrew Morton , aubrey.li@intel.com, Linux API , LKML List-Id: linux-api@vger.kernel.org On 2019/4/10 10:25, Andy Lutomirski wrote: > On Tue, Apr 9, 2019 at 7:20 PM Li, Aubrey wrote: >> >> On 2019/4/10 9:58, Andy Lutomirski wrote: >>> On Tue, Apr 9, 2019 at 6:55 PM Aubrey Li wrote: >>>> >>>> The architecture specific information of the running processes could >>>> be useful to the userland. Add support to examine process architecture >>>> specific information externally. >>>> >>>> Signed-off-by: Aubrey Li >>>> Cc: Peter Zijlstra >>>> Cc: Andi Kleen >>>> Cc: Tim Chen >>>> Cc: Dave Hansen >>>> Cc: Arjan van de Ven >>>> Cc: Linux API >>>> Cc: Alexey Dobriyan >>>> Cc: Andrew Morton >>>> --- >>>> fs/proc/array.c | 5 +++++ >>>> include/linux/proc_fs.h | 2 ++ >>>> 2 files changed, 7 insertions(+) >>>> >>>> diff --git a/fs/proc/array.c b/fs/proc/array.c >>>> index 2edbb657f859..331592a61718 100644 >>>> --- a/fs/proc/array.c >>>> +++ b/fs/proc/array.c >>>> @@ -401,6 +401,10 @@ static inline void task_thp_status(struct seq_file *m, struct mm_struct *mm) >>>> seq_printf(m, "THP_enabled:\t%d\n", thp_enabled); >>>> } >>>> >>>> +void __weak arch_proc_pid_status(struct seq_file *m, struct task_struct *task) >>>> +{ >>>> +} >>> >>> This pointlessly bloats other architectures. Do this instead in an >>> appropriate header: >>> >>> #ifndef arch_proc_pid_status >>> static inline void arch_proc_pid_status(...) >>> { >>> } >>> #endif >>> >> >> I saw a bunch of similar weak functions, is it not acceptable? >> >> fs/proc$ grep weak *.c >> cpuinfo.c:__weak void arch_freq_prepare_all(void) >> meminfo.c:void __attribute__((weak)) arch_report_meminfo(struct seq_file *m) >> vmcore.c:int __weak elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size) >> vmcore.c:void __weak elfcorehdr_free(unsigned long long addr) >> vmcore.c:ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos) >> vmcore.c:ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos) >> vmcore.c:int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma, >> vmcore.c:ssize_t __weak > > I think they're acceptable, but I don't personally like them. > okay, let me try to see if I can refine it in an appropriate way. >> >>> Or add /proc/PID/x86_status, which sounds better in most respects to me. >>> >> >> I didn't figure out how to make /proc/PID/x86_status invisible to other >> architectures in an appropriate way, do you have any suggestions? > > #ifdef CONFIG_X86? > I'm not sure if everyone like adding an arch #ifdef in a common file, please allow me to wait a while to see if there are other comments. Thanks, -Aubrey