| Message ID | 20180718235710.18242-5-jmkrzyszt@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 19 Jul 2018 01:57:06 +0200 Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote: > Further optimize processing speed of read/write callback functions by > resolving private structure pointer only once per callback and passing > it to all subfunctions instead of mtd_info. Not sure this has a real impact on perfs, but I also prefer not using mtd_info objects within NAND drivers, so I'm good with the change itself (its probably worth changing the commit message though) > > Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> > --- > drivers/mtd/nand/raw/ams-delta.c | 44 +++++++++++++++++++++++----------------- > 1 file changed, 25 insertions(+), 19 deletions(-) > > diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c > index dfefcd79b420..d7e4c9dbef67 100644 > --- a/drivers/mtd/nand/raw/ams-delta.c > +++ b/drivers/mtd/nand/raw/ams-delta.c > @@ -72,10 +72,9 @@ static const struct mtd_partition partition_info[] = { > .size = 3 * SZ_256K }, > }; > > -static void ams_delta_write_next_byte(struct mtd_info *mtd, u_char byte) > +static void ams_delta_write_next_byte(struct ams_delta_nand *priv, u_char byte) > { > - struct nand_chip *this = mtd_to_nand(mtd); > - struct ams_delta_nand *priv = nand_get_controller_data(this); > + struct nand_chip *this = &priv->nand_chip; > > writew(byte, this->IO_ADDR_W); > gpiod_set_value(priv->gpiod_nwe, 0); > @@ -83,21 +82,18 @@ static void ams_delta_write_next_byte(struct mtd_info *mtd, u_char byte) > gpiod_set_value(priv->gpiod_nwe, 1); > } > > -static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte) > +static void ams_delta_write_first_byte(struct ams_delta_nand *priv, u_char byte) > { > - struct nand_chip *this = mtd_to_nand(mtd); > - struct ams_delta_nand *priv = nand_get_controller_data(this); > void __iomem *io_base = priv->io_base; > > writew(0, io_base + OMAP_MPUIO_IO_CNTL); > > - ams_delta_write_next_byte(mtd, byte); > + ams_delta_write_next_byte(priv, byte); > } > > -static u_char ams_delta_read_next_byte(struct mtd_info *mtd) > +static u_char ams_delta_read_next_byte(struct ams_delta_nand *priv) > { > - struct nand_chip *this = mtd_to_nand(mtd); > - struct ams_delta_nand *priv = nand_get_controller_data(this); > + struct nand_chip *this = &priv->nand_chip; > u_char res; > > gpiod_set_value(priv->gpiod_nre, 0); > @@ -108,36 +104,46 @@ static u_char ams_delta_read_next_byte(struct mtd_info *mtd) > return res; > } > > -static u_char ams_delta_read_byte(struct mtd_info *mtd) > +static u_char ams_delta_read_first_byte(struct ams_delta_nand *priv) > { > - struct nand_chip *this = mtd_to_nand(mtd); > - struct ams_delta_nand *priv = nand_get_controller_data(this); > void __iomem *io_base = priv->io_base; > > writew(~0, io_base + OMAP_MPUIO_IO_CNTL); > > - return ams_delta_read_next_byte(mtd); > + return ams_delta_read_next_byte(priv); > +} > + > +static u_char ams_delta_read_byte(struct mtd_info *mtd) > +{ > + struct nand_chip *this = mtd_to_nand(mtd); > + struct ams_delta_nand *priv = nand_get_controller_data(this); > + > + return ams_delta_read_first_byte(priv); > } > > static void ams_delta_write_buf(struct mtd_info *mtd, const u_char *buf, > int len) > { > + struct nand_chip *this = mtd_to_nand(mtd); > + struct ams_delta_nand *priv = nand_get_controller_data(this); > int i; > > if (len > 0) > - ams_delta_write_byte(mtd, buf[0]); > + ams_delta_write_first_byte(priv, buf[0]); > for (i = 1; i < len; i++) > - ams_delta_write_next_byte(mtd, buf[i]); > + ams_delta_write_next_byte(priv, buf[i]); > } > > static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len) > { > + struct nand_chip *this = mtd_to_nand(mtd); > + struct ams_delta_nand *priv = nand_get_controller_data(this); > int i; > > if (len > 0) > - buf[0] = ams_delta_read_byte(mtd); > + buf[0] = ams_delta_read_first_byte(priv); > for (i = 1; i < len; i++) > - buf[i] = ams_delta_read_next_byte(mtd); > + buf[i] = ams_delta_read_next_byte(priv); > } > > /* > @@ -161,7 +167,7 @@ static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd, > } > > if (cmd != NAND_CMD_NONE) > - ams_delta_write_byte(mtd, cmd); > + ams_delta_write_first_byte(priv, cmd); > } > > static int ams_delta_nand_ready(struct mtd_info *mtd)
On Thursday, July 19, 2018 8:25:38 AM CEST Boris Brezillon wrote: > On Thu, 19 Jul 2018 01:57:06 +0200 > Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote: > > > Further optimize processing speed of read/write callback functions by > > resolving private structure pointer only once per callback and passing > > it to all subfunctions instead of mtd_info. OK, I'll call it simplification (the code looks more simple after that, doesn't it), not optimization if you agree. Thanks, Janusz
On Fri, 20 Jul 2018 20:14:55 +0200 Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote: > On Thursday, July 19, 2018 8:25:38 AM CEST Boris Brezillon wrote: > > On Thu, 19 Jul 2018 01:57:06 +0200 > > Janusz Krzysztofik <jmkrzyszt@gmail.com> wrote: > > > > > Further optimize processing speed of read/write callback functions by > > > resolving private structure pointer only once per callback and passing > > > it to all subfunctions instead of mtd_info. > > OK, I'll call it simplification (the code looks more simple after that, doesn't > it), Yep. > not optimization if you agree. > > Thanks, > Janusz > > >
diff --git a/drivers/mtd/nand/raw/ams-delta.c b/drivers/mtd/nand/raw/ams-delta.c index dfefcd79b420..d7e4c9dbef67 100644 --- a/drivers/mtd/nand/raw/ams-delta.c +++ b/drivers/mtd/nand/raw/ams-delta.c @@ -72,10 +72,9 @@ static const struct mtd_partition partition_info[] = { .size = 3 * SZ_256K }, }; -static void ams_delta_write_next_byte(struct mtd_info *mtd, u_char byte) +static void ams_delta_write_next_byte(struct ams_delta_nand *priv, u_char byte) { - struct nand_chip *this = mtd_to_nand(mtd); - struct ams_delta_nand *priv = nand_get_controller_data(this); + struct nand_chip *this = &priv->nand_chip; writew(byte, this->IO_ADDR_W); gpiod_set_value(priv->gpiod_nwe, 0); @@ -83,21 +82,18 @@ static void ams_delta_write_next_byte(struct mtd_info *mtd, u_char byte) gpiod_set_value(priv->gpiod_nwe, 1); } -static void ams_delta_write_byte(struct mtd_info *mtd, u_char byte) +static void ams_delta_write_first_byte(struct ams_delta_nand *priv, u_char byte) { - struct nand_chip *this = mtd_to_nand(mtd); - struct ams_delta_nand *priv = nand_get_controller_data(this); void __iomem *io_base = priv->io_base; writew(0, io_base + OMAP_MPUIO_IO_CNTL); - ams_delta_write_next_byte(mtd, byte); + ams_delta_write_next_byte(priv, byte); } -static u_char ams_delta_read_next_byte(struct mtd_info *mtd) +static u_char ams_delta_read_next_byte(struct ams_delta_nand *priv) { - struct nand_chip *this = mtd_to_nand(mtd); - struct ams_delta_nand *priv = nand_get_controller_data(this); + struct nand_chip *this = &priv->nand_chip; u_char res; gpiod_set_value(priv->gpiod_nre, 0); @@ -108,36 +104,46 @@ static u_char ams_delta_read_next_byte(struct mtd_info *mtd) return res; } -static u_char ams_delta_read_byte(struct mtd_info *mtd) +static u_char ams_delta_read_first_byte(struct ams_delta_nand *priv) { - struct nand_chip *this = mtd_to_nand(mtd); - struct ams_delta_nand *priv = nand_get_controller_data(this); void __iomem *io_base = priv->io_base; writew(~0, io_base + OMAP_MPUIO_IO_CNTL); - return ams_delta_read_next_byte(mtd); + return ams_delta_read_next_byte(priv); +} + +static u_char ams_delta_read_byte(struct mtd_info *mtd) +{ + struct nand_chip *this = mtd_to_nand(mtd); + struct ams_delta_nand *priv = nand_get_controller_data(this); + + return ams_delta_read_first_byte(priv); } static void ams_delta_write_buf(struct mtd_info *mtd, const u_char *buf, int len) { + struct nand_chip *this = mtd_to_nand(mtd); + struct ams_delta_nand *priv = nand_get_controller_data(this); int i; if (len > 0) - ams_delta_write_byte(mtd, buf[0]); + ams_delta_write_first_byte(priv, buf[0]); for (i = 1; i < len; i++) - ams_delta_write_next_byte(mtd, buf[i]); + ams_delta_write_next_byte(priv, buf[i]); } static void ams_delta_read_buf(struct mtd_info *mtd, u_char *buf, int len) { + struct nand_chip *this = mtd_to_nand(mtd); + struct ams_delta_nand *priv = nand_get_controller_data(this); int i; if (len > 0) - buf[0] = ams_delta_read_byte(mtd); + buf[0] = ams_delta_read_first_byte(priv); for (i = 1; i < len; i++) - buf[i] = ams_delta_read_next_byte(mtd); + buf[i] = ams_delta_read_next_byte(priv); } /* @@ -161,7 +167,7 @@ static void ams_delta_hwcontrol(struct mtd_info *mtd, int cmd, } if (cmd != NAND_CMD_NONE) - ams_delta_write_byte(mtd, cmd); + ams_delta_write_first_byte(priv, cmd); } static int ams_delta_nand_ready(struct mtd_info *mtd)
Further optimize processing speed of read/write callback functions by resolving private structure pointer only once per callback and passing it to all subfunctions instead of mtd_info. Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> --- drivers/mtd/nand/raw/ams-delta.c | 44 +++++++++++++++++++++++----------------- 1 file changed, 25 insertions(+), 19 deletions(-)