On Wed, Feb 11, 2015 at 8:16 PM, Linux Kernel Mailing List <linux-kernel@xxxxxxxxxxxxxxx> wrote: > Gitweb: http://git.kernel.org/linus/;a=commit;h=ded85c193a391a84076d5c6a7a5668fe164a490e > Commit: ded85c193a391a84076d5c6a7a5668fe164a490e > Parent: b0a93d96b2814c725161f91a4e35d0c29ec0f95b > Refname: refs/heads/master > Author: Hannes Reinecke <hare@xxxxxxx> > AuthorDate: Thu Jan 8 07:43:42 2015 +0100 > Committer: Christoph Hellwig <hch@xxxxxx> > CommitDate: Fri Jan 9 15:44:28 2015 +0100 > > scsi: Implement per-cpu logging buffer > > Implement a per-cpu buffer for formatting messages to avoid line breaks > up under high load. This patch implements scmd_printk() and > sdev_prefix_printk() using the per-cpu buffer and makes sdev_printk() a > wrapper for sdev_prefix_printk(). > > Tested-by: Robert Elliott <elliott@xxxxxx> > Reviewed-by: Robert Elliott <elliott@xxxxxx> > Signed-off-by: Hannes Reinecke <hare@xxxxxxx> > Signed-off-by: Christoph Hellwig <hch@xxxxxx> > --- /dev/null > +++ b/drivers/scsi/scsi_logging.c > +#define SCSI_LOG_SPOOLSIZE 4096 > +#define SCSI_LOG_BUFSIZE 128 > + > +#if (SCSI_LOG_SPOOLSIZE / SCSI_LOG_BUFSIZE) > BITS_PER_LONG > +#warning SCSI logging bitmask too large > +#endif > + > +struct scsi_log_buf { > + char buffer[SCSI_LOG_SPOOLSIZE]; > + unsigned long map; > +}; > + > +static DEFINE_PER_CPU(struct scsi_log_buf, scsi_format_log); Do we really need a static 4 KiB per-CPU buffer? bloat-o-meter: add/remove: 183/94 grow/shrink: 314/211 up/down: 33467/-21291 (12176) function old new delta scsi_format_log - 4100 +4100 handle_mm_fault 1794 2750 +956 scsi_log_print_sense_hdr - 774 +774 proc_keys_show - 770 +770 Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
