| Message ID | 20180615223659.32420-1-bart.vanassche@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 16.06.2018 01:36, Bart Van Assche wrote: > The C programming language does not allow to use preprocessor statements > inside macro arguments (pr_info() is defined as a macro). Hence rework > the pr_info() statement in btrfs_print_mod_info() such that it becomes > compliant. This patch allows tools like sparse to analyze the BTRFS > source code. > > Fixes: 62e855771dac ("btrfs: convert printk(KERN_* to use pr_* calls") > Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> > Cc: Jeff Mahoney <jeffm@suse.com> > Cc: David Sterba <dsterba@suse.com> > --- > fs/btrfs/super.c | 6 +++--- > 1 file changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > index 81107ad49f3a..dd4980df5b8e 100644 > --- a/fs/btrfs/super.c > +++ b/fs/btrfs/super.c > @@ -2369,7 +2369,7 @@ static __cold void btrfs_interface_exit(void) > > static void __init btrfs_print_mod_info(void) > { > - pr_info("Btrfs loaded, crc32c=%s" > + static const char fmt[] = KERN_INFO "Btrfs loaded, crc32c=%s" > #ifdef CONFIG_BTRFS_DEBUG > ", debug=on" > #endif > @@ -2382,8 +2382,8 @@ static void __init btrfs_print_mod_info(void) > #ifdef CONFIG_BTRFS_FS_REF_VERIFY > ", ref-verify=on" > #endif > - "\n", > - crc32c_impl()); > + "\n"; > + printk(fmt, crc32c_impl()); I'd rather not see more printk being added. Nothing prevents from having the fmt string being passed to pr_info. > } > > static int __init init_btrfs_fs(void) > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Sat, Jun 16, 2018 at 01:28:13PM +0300, Nikolay Borisov wrote: > > > On 16.06.2018 01:36, Bart Van Assche wrote: > > The C programming language does not allow to use preprocessor statements > > inside macro arguments (pr_info() is defined as a macro). Hence rework > > the pr_info() statement in btrfs_print_mod_info() such that it becomes > > compliant. This patch allows tools like sparse to analyze the BTRFS > > source code. > > > > Fixes: 62e855771dac ("btrfs: convert printk(KERN_* to use pr_* calls") > > Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> > > Cc: Jeff Mahoney <jeffm@suse.com> > > Cc: David Sterba <dsterba@suse.com> > > --- > > fs/btrfs/super.c | 6 +++--- > > 1 file changed, 3 insertions(+), 3 deletions(-) > > > > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > > index 81107ad49f3a..dd4980df5b8e 100644 > > --- a/fs/btrfs/super.c > > +++ b/fs/btrfs/super.c > > @@ -2369,7 +2369,7 @@ static __cold void btrfs_interface_exit(void) > > > > static void __init btrfs_print_mod_info(void) > > { > > - pr_info("Btrfs loaded, crc32c=%s" > > + static const char fmt[] = KERN_INFO "Btrfs loaded, crc32c=%s" > > #ifdef CONFIG_BTRFS_DEBUG > > ", debug=on" > > #endif > > @@ -2382,8 +2382,8 @@ static void __init btrfs_print_mod_info(void) > > #ifdef CONFIG_BTRFS_FS_REF_VERIFY > > ", ref-verify=on" > > #endif > > - "\n", > > - crc32c_impl()); > > + "\n"; > > + printk(fmt, crc32c_impl()); > > I'd rather not see more printk being added. Nothing prevents from having > the fmt string being passed to pr_info. So you mean to do + static const char fmt[] = "Btrfs loaded, crc32c=%s" + pr_info(fmt); ? -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 18.06.2018 12:26, David Sterba wrote: > On Sat, Jun 16, 2018 at 01:28:13PM +0300, Nikolay Borisov wrote: >> >> >> On 16.06.2018 01:36, Bart Van Assche wrote: >>> The C programming language does not allow to use preprocessor statements >>> inside macro arguments (pr_info() is defined as a macro). Hence rework >>> the pr_info() statement in btrfs_print_mod_info() such that it becomes >>> compliant. This patch allows tools like sparse to analyze the BTRFS >>> source code. >>> >>> Fixes: 62e855771dac ("btrfs: convert printk(KERN_* to use pr_* calls") >>> Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> >>> Cc: Jeff Mahoney <jeffm@suse.com> >>> Cc: David Sterba <dsterba@suse.com> >>> --- >>> fs/btrfs/super.c | 6 +++--- >>> 1 file changed, 3 insertions(+), 3 deletions(-) >>> >>> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c >>> index 81107ad49f3a..dd4980df5b8e 100644 >>> --- a/fs/btrfs/super.c >>> +++ b/fs/btrfs/super.c >>> @@ -2369,7 +2369,7 @@ static __cold void btrfs_interface_exit(void) >>> >>> static void __init btrfs_print_mod_info(void) >>> { >>> - pr_info("Btrfs loaded, crc32c=%s" >>> + static const char fmt[] = KERN_INFO "Btrfs loaded, crc32c=%s" >>> #ifdef CONFIG_BTRFS_DEBUG >>> ", debug=on" >>> #endif >>> @@ -2382,8 +2382,8 @@ static void __init btrfs_print_mod_info(void) >>> #ifdef CONFIG_BTRFS_FS_REF_VERIFY >>> ", ref-verify=on" >>> #endif >>> - "\n", >>> - crc32c_impl()); >>> + "\n"; >>> + printk(fmt, crc32c_impl()); >> >> I'd rather not see more printk being added. Nothing prevents from having >> the fmt string being passed to pr_info. > > So you mean to do > > + static const char fmt[] = "Btrfs loaded, crc32c=%s" > + pr_info(fmt); Pretty much, something along the lines of pr_info(fmt, crc32c_impl). printk requires having the KERN_INFO in the format string, which I see no point in doing, correct me if I'm wrong? > > ? > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, 2018-06-18 at 12:31 +0300, Nikolay Borisov wrote: > On 18.06.2018 12:26, David Sterba wrote: > > On Sat, Jun 16, 2018 at 01:28:13PM +0300, Nikolay Borisov wrote: > > > I'd rather not see more printk being added. Nothing prevents from having > > > the fmt string being passed to pr_info. > > > > So you mean to do > > > > + static const char fmt[] = "Btrfs loaded, crc32c=%s" > > + pr_info(fmt); > > Pretty much, something along the lines of > > pr_info(fmt, crc32c_impl). > > printk requires having the KERN_INFO in the format string, which I see > no point in doing, correct me if I'm wrong? You should know that what you proposed doesn't compile because pr_info() relies on string concatenation and hence requires that its first argument is a string constant instead of a const char pointer. Anyway, I will rework this patch such that it uses pr_info() instead of printk(). Bart.
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 81107ad49f3a..dd4980df5b8e 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -2369,7 +2369,7 @@ static __cold void btrfs_interface_exit(void) static void __init btrfs_print_mod_info(void) { - pr_info("Btrfs loaded, crc32c=%s" + static const char fmt[] = KERN_INFO "Btrfs loaded, crc32c=%s" #ifdef CONFIG_BTRFS_DEBUG ", debug=on" #endif @@ -2382,8 +2382,8 @@ static void __init btrfs_print_mod_info(void) #ifdef CONFIG_BTRFS_FS_REF_VERIFY ", ref-verify=on" #endif - "\n", - crc32c_impl()); + "\n"; + printk(fmt, crc32c_impl()); } static int __init init_btrfs_fs(void)
The C programming language does not allow to use preprocessor statements inside macro arguments (pr_info() is defined as a macro). Hence rework the pr_info() statement in btrfs_print_mod_info() such that it becomes compliant. This patch allows tools like sparse to analyze the BTRFS source code. Fixes: 62e855771dac ("btrfs: convert printk(KERN_* to use pr_* calls") Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: David Sterba <dsterba@suse.com> --- fs/btrfs/super.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)