Joe Perches
2015-Apr-17 07:17 UTC
[Ocfs2-devel] [PATCH next] ocfs2: Reduce object size of mlog uses
Using a function for __mlog_printk instead of a macro reduces the object size of built-in.o more than 120KB, or ~10% overall (x86-64 defconfig with all ocfs2 options) $ size fs/ocfs2/built-in.o* text data bss dec hex filename 936255 118071 134408 1188734 12237e fs/ocfs2/built-in.o.new 1064081 118071 134408 1316560 1416d0 fs/ocfs2/built-in.o.old Miscellanea: o Neaten macros around the __mlog_printk uses. o Use __func__ for __PRETTY_FUNCTION__ o Use ##__VA_ARGS__ for args... Signed-off-by: Joe Perches <joe at perches.com> --- Compiled/untested fs/ocfs2/cluster/masklog.c | 17 +++++++++++++++++ fs/ocfs2/cluster/masklog.h | 28 +++++++++++++++++----------- 2 files changed, 34 insertions(+), 11 deletions(-) diff --git a/fs/ocfs2/cluster/masklog.c b/fs/ocfs2/cluster/masklog.c index af7598b..5b7a351 100644 --- a/fs/ocfs2/cluster/masklog.c +++ b/fs/ocfs2/cluster/masklog.c @@ -64,6 +64,23 @@ static ssize_t mlog_mask_store(u64 mask, const char *buf, size_t count) return count; } +void __mlog_printk(const char *level, const char *func, int line, + const char *fmt, ...) +{ + struct va_format vaf; + va_list args; + + va_start(args, fmt); + + vaf.fmt = fmt; + vaf.va = &args; + + printk("%s(%s,%u,%lu):%s:%d %pV", + level, current->comm, task_pid_nr(current), __mlog_cpu_guess, + func, line, &vaf); + + va_end(args); +} struct mlog_attribute { struct attribute attr; u64 mask; diff --git a/fs/ocfs2/cluster/masklog.h b/fs/ocfs2/cluster/masklog.h index 7fdc25a..6036e6a 100644 --- a/fs/ocfs2/cluster/masklog.h +++ b/fs/ocfs2/cluster/masklog.h @@ -168,7 +168,8 @@ extern struct mlog_bits mlog_and_bits, mlog_not_bits; * scream. just do this instead of trying to guess which we're building * against.. *sigh*. */ -#define __mlog_cpu_guess ({ \ +#define __mlog_cpu_guess \ +({ \ unsigned long _cpu = get_cpu(); \ put_cpu(); \ _cpu; \ @@ -178,21 +179,25 @@ extern struct mlog_bits mlog_and_bits, mlog_not_bits; * before ##args is intentional. Otherwise, gcc 2.95 will eat the * previous token if args expands to nothing. */ -#define __mlog_printk(level, fmt, args...) \ - printk(level "(%s,%u,%lu):%s:%d " fmt, current->comm, \ - task_pid_nr(current), __mlog_cpu_guess, \ - __PRETTY_FUNCTION__, __LINE__ , ##args) +__printf(4, 5) +void __mlog_printk(const char *level, const char *func, int line, + const char *fmt, ...); -#define mlog(mask, fmt, args...) do { \ +#define mlog(mask, fmt, ...) \ +do { \ u64 __m = MLOG_MASK_PREFIX | (mask); \ if ((__m & ML_ALLOWED_BITS) && \ __mlog_test_u64(__m, mlog_and_bits) && \ !__mlog_test_u64(__m, mlog_not_bits)) { \ if (__m & ML_ERROR) \ - __mlog_printk(KERN_ERR, "ERROR: "fmt , ##args); \ + __mlog_printk(KERN_ERR, __func__, __LINE__, \ + "ERROR: " fmt, ##__VA_ARGS__); \ else if (__m & ML_NOTICE) \ - __mlog_printk(KERN_NOTICE, fmt , ##args); \ - else __mlog_printk(KERN_INFO, fmt , ##args); \ + __mlog_printk(KERN_NOTICE, __func__, __LINE__, \ + fmt, ##__VA_ARGS__); \ + else \ + __mlog_printk(KERN_INFO, __func__, __LINE__, \ + fmt, ##__VA_ARGS__); \ } \ } while (0) @@ -205,10 +210,11 @@ extern struct mlog_bits mlog_and_bits, mlog_not_bits; _st; \ }) -#define mlog_bug_on_msg(cond, fmt, args...) do { \ +#define mlog_bug_on_msg(cond, fmt, ...) \ +do { \ if (cond) { \ mlog(ML_ERROR, "bug expression: " #cond "\n"); \ - mlog(ML_ERROR, fmt, ##args); \ + mlog(ML_ERROR, fmt, ##__VA_ARGS__); \ BUG(); \ } \ } while (0)
Andrew Morton
2015-Apr-22 22:46 UTC
[Ocfs2-devel] [PATCH next] ocfs2: Reduce object size of mlog uses
On Fri, 17 Apr 2015 00:17:50 -0700 Joe Perches <joe at perches.com> wrote:> Using a function for __mlog_printk instead of a macro > reduces the object size of built-in.o more than 120KB, or > ~10% overall (x86-64 defconfig with all ocfs2 options) > > $ size fs/ocfs2/built-in.o* > text data bss dec hex filename > 936255 118071 134408 1188734 12237e fs/ocfs2/built-in.o.new > 1064081 118071 134408 1316560 1416d0 fs/ocfs2/built-in.o.oldIt's a start.> --- a/fs/ocfs2/cluster/masklog.c > +++ b/fs/ocfs2/cluster/masklog.c > @@ -64,6 +64,23 @@ static ssize_t mlog_mask_store(u64 mask, const char *buf, size_t count) > return count; > } > > +void __mlog_printk(const char *level, const char *func, int line, > + const char *fmt, ...) > +{ > + struct va_format vaf; > + va_list args; > + > + va_start(args, fmt); > + > + vaf.fmt = fmt; > + vaf.va = &args; > + > + printk("%s(%s,%u,%lu):%s:%d %pV", > + level, current->comm, task_pid_nr(current), __mlog_cpu_guess, > + func, line, &vaf); > + > + va_end(args); > +}Logging function-name and line-number was a bit weird. I wonder if anyone will mind if this is converted to file-n-line, as God intended. That will shrink rodata a bit, because number-of-files is a lot less than number-of-functions.> struct mlog_attribute { > struct attribute attr; > u64 mask; > diff --git a/fs/ocfs2/cluster/masklog.h b/fs/ocfs2/cluster/masklog.h > index 7fdc25a..6036e6a 100644 > --- a/fs/ocfs2/cluster/masklog.h > +++ b/fs/ocfs2/cluster/masklog.h > @@ -168,7 +168,8 @@ extern struct mlog_bits mlog_and_bits, mlog_not_bits; > * scream. just do this instead of trying to guess which we're building > * against.. *sigh*. > */ > -#define __mlog_cpu_guess ({ \ > +#define __mlog_cpu_guess \ > +({ \While we're in there we should turn this into __mlog_cpu_guess(). Or, preferably, just zap the sorry thing and use raw_smp_processor_id().> unsigned long _cpu = get_cpu(); \ > put_cpu(); \ > _cpu; \ > @@ -178,21 +179,25 @@ extern struct mlog_bits mlog_and_bits, mlog_not_bits; > * before ##args is intentional. Otherwise, gcc 2.95 will eat the > * previous token if args expands to nothing. > */ > -#define __mlog_printk(level, fmt, args...) \ > - printk(level "(%s,%u,%lu):%s:%d " fmt, current->comm, \ > - task_pid_nr(current), __mlog_cpu_guess, \ > - __PRETTY_FUNCTION__, __LINE__ , ##args) > +__printf(4, 5) > +void __mlog_printk(const char *level, const char *func, int line, > + const char *fmt, ...); > > -#define mlog(mask, fmt, args...) do { \ > +#define mlog(mask, fmt, ...) \ > +do { \ > u64 __m = MLOG_MASK_PREFIX | (mask); \ > if ((__m & ML_ALLOWED_BITS) && \ > __mlog_test_u64(__m, mlog_and_bits) && \ > !__mlog_test_u64(__m, mlog_not_bits)) { \ > if (__m & ML_ERROR) \All this goop can also be uninlined?> - __mlog_printk(KERN_ERR, "ERROR: "fmt , ##args); \ > + __mlog_printk(KERN_ERR, __func__, __LINE__, \ > + "ERROR: " fmt, ##__VA_ARGS__); \ > else if (__m & ML_NOTICE) \ > - __mlog_printk(KERN_NOTICE, fmt , ##args); \ > - else __mlog_printk(KERN_INFO, fmt , ##args); \ > + __mlog_printk(KERN_NOTICE, __func__, __LINE__, \ > + fmt, ##__VA_ARGS__); \ > + else \ > + __mlog_printk(KERN_INFO, __func__, __LINE__, \ > + fmt, ##__VA_ARGS__); \ > } \ > } while (0) >I guess this patch is a step on the way - a 10% shrink is decent. But I believe that with full uninlining of the ocfs2 logging code we can shrink the filesystem's footprint by 50%. This code needs some pretty serious rework and rethink, perhaps involving a change to the emitted info. I was hoping one of the ocfs2 developers would take the bait, but they're all in hiding. If you feel like undertaking such a rotorooting then go wild - that should wake 'em up ;)