2009/5/31 Baruch Siach <baruch@xxxxxxxxxx>: > On Thu, May 28, 2009 at 09:32:37AM +0200, Linus Walleij wrote: >> 2009/5/28 Baruch Siach <baruch@xxxxxxxxxx>: >> >> >> > +static int dw_i2c_probe(struct platform_device *pdev) >> >> >> >> Can you tag this with __init? >> > >> > OK. __devinit is probably better. >> >> I don't think any platform_device tagged with __devinit is >> correct really, platform_device:s cannot be hotplugged that's >> against the definition of a platform_device. > > Doesn't this __devinit have something to do with the ability to compile the > driver as a module (as is the case here)? See for example > drivers/watchdog/omap_wdt.c and commit > 0e3912c75f42986c17d955542247bf04c6eef738 In that case I doubt that even module_init() could be __init, as it is. The linkage handling of these symbols is defined in: include/asm-generic/vmlinux.lds.h As you can see: #ifdef CONFIG_HOTPLUG #define DEV_KEEP(sec) *(.dev##sec) #define DEV_DISCARD(sec) #else #define DEV_KEEP(sec) #define DEV_DISCARD(sec) *(.dev##sec) #endif Further down the file you can see how this is handled in different kinds of symbols. It is kept if CONFIG_HOTPLUG is set, it is moved into the DATA_DATA section and kept in memory (so that it can be reused when devices are plugged/unplugged) else it is discarded after init. In practice this means that if you device is _NOT_ hot-pluggable, the kernel will still nevertheless keep all the code in __devinit and __devexit around which means that __devinit code cannot be free:ed after init and it increases the footprint of your kernel for no good reason. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
