| Message ID | 20190501092841.9026-3-rasmus.villemoes@prevas.dk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | soc/fsl/qe: cleanups and new DT binding | expand |
Le 01/05/2019 à 11:29, Rasmus Villemoes a écrit : > The current array of struct qe_snum use 256*4 bytes for just keeping > track of the free/used state of each index, and the struct layout > means there's another 768 bytes of padding. If we just unzip that > structure, the array of snum values just use 256 bytes, while the > free/inuse state can be tracked in a 32 byte bitmap. > > So this reduces the .data footprint by 1760 bytes. It also serves as > preparation for introducing another DT binding for specifying the snum > values. > > Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr> Trivial comment below > --- > drivers/soc/fsl/qe/qe.c | 43 ++++++++++++----------------------------- > 1 file changed, 12 insertions(+), 31 deletions(-) > > diff --git a/drivers/soc/fsl/qe/qe.c b/drivers/soc/fsl/qe/qe.c > index 855373deb746..303aa29cb27d 100644 > --- a/drivers/soc/fsl/qe/qe.c > +++ b/drivers/soc/fsl/qe/qe.c > @@ -14,6 +14,7 @@ > * Free Software Foundation; either version 2 of the License, or (at your > * option) any later version. > */ > +#include <linux/bitmap.h> > #include <linux/errno.h> > #include <linux/sched.h> > #include <linux/kernel.h> > @@ -43,25 +44,14 @@ static DEFINE_SPINLOCK(qe_lock); > DEFINE_SPINLOCK(cmxgcr_lock); > EXPORT_SYMBOL(cmxgcr_lock); > > -/* QE snum state */ > -enum qe_snum_state { > - QE_SNUM_STATE_USED, > - QE_SNUM_STATE_FREE > -}; > - > -/* QE snum */ > -struct qe_snum { > - u8 num; > - enum qe_snum_state state; > -}; > - > /* We allocate this here because it is used almost exclusively for > * the communication processor devices. > */ > struct qe_immap __iomem *qe_immr; > EXPORT_SYMBOL(qe_immr); > > -static struct qe_snum snums[QE_NUM_OF_SNUM]; /* Dynamically allocated SNUMs */ > +static u8 snums[QE_NUM_OF_SNUM]; /* Dynamically allocated SNUMs */ > +static DECLARE_BITMAP(snum_state, QE_NUM_OF_SNUM); > static unsigned int qe_num_of_snum; > > static phys_addr_t qebase = -1; > @@ -315,10 +305,8 @@ static void qe_snums_init(void) > else > snum_init = snum_init_46; > > - for (i = 0; i < qe_num_of_snum; i++) { > - snums[i].num = snum_init[i]; > - snums[i].state = QE_SNUM_STATE_FREE; > - } > + bitmap_zero(snum_state, QE_NUM_OF_SNUM); > + memcpy(snums, snum_init, qe_num_of_snum); > } > > int qe_get_snum(void) > @@ -328,12 +316,10 @@ int qe_get_snum(void) > int i; > > spin_lock_irqsave(&qe_lock, flags); > - for (i = 0; i < qe_num_of_snum; i++) { > - if (snums[i].state == QE_SNUM_STATE_FREE) { > - snums[i].state = QE_SNUM_STATE_USED; > - snum = snums[i].num; > - break; > - } > + i = find_first_zero_bit(snum_state, qe_num_of_snum); > + if (i < qe_num_of_snum) { > + set_bit(i, snum_state); > + snum = snums[i]; > } > spin_unlock_irqrestore(&qe_lock, flags); > > @@ -343,14 +329,9 @@ EXPORT_SYMBOL(qe_get_snum); > > void qe_put_snum(u8 snum) > { > - int i; > - > - for (i = 0; i < qe_num_of_snum; i++) { > - if (snums[i].num == snum) { > - snums[i].state = QE_SNUM_STATE_FREE; > - break; > - } > - } > + const u8 *p = memchr(snums, snum, qe_num_of_snum); A blank line is expected here. Christophe > + if (p) > + clear_bit(p - snums, snum_state); > } > EXPORT_SYMBOL(qe_put_snum); > >
diff --git a/drivers/soc/fsl/qe/qe.c b/drivers/soc/fsl/qe/qe.c index 855373deb746..303aa29cb27d 100644 --- a/drivers/soc/fsl/qe/qe.c +++ b/drivers/soc/fsl/qe/qe.c @@ -14,6 +14,7 @@ * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. */ +#include <linux/bitmap.h> #include <linux/errno.h> #include <linux/sched.h> #include <linux/kernel.h> @@ -43,25 +44,14 @@ static DEFINE_SPINLOCK(qe_lock); DEFINE_SPINLOCK(cmxgcr_lock); EXPORT_SYMBOL(cmxgcr_lock); -/* QE snum state */ -enum qe_snum_state { - QE_SNUM_STATE_USED, - QE_SNUM_STATE_FREE -}; - -/* QE snum */ -struct qe_snum { - u8 num; - enum qe_snum_state state; -}; - /* We allocate this here because it is used almost exclusively for * the communication processor devices. */ struct qe_immap __iomem *qe_immr; EXPORT_SYMBOL(qe_immr); -static struct qe_snum snums[QE_NUM_OF_SNUM]; /* Dynamically allocated SNUMs */ +static u8 snums[QE_NUM_OF_SNUM]; /* Dynamically allocated SNUMs */ +static DECLARE_BITMAP(snum_state, QE_NUM_OF_SNUM); static unsigned int qe_num_of_snum; static phys_addr_t qebase = -1; @@ -315,10 +305,8 @@ static void qe_snums_init(void) else snum_init = snum_init_46; - for (i = 0; i < qe_num_of_snum; i++) { - snums[i].num = snum_init[i]; - snums[i].state = QE_SNUM_STATE_FREE; - } + bitmap_zero(snum_state, QE_NUM_OF_SNUM); + memcpy(snums, snum_init, qe_num_of_snum); } int qe_get_snum(void) @@ -328,12 +316,10 @@ int qe_get_snum(void) int i; spin_lock_irqsave(&qe_lock, flags); - for (i = 0; i < qe_num_of_snum; i++) { - if (snums[i].state == QE_SNUM_STATE_FREE) { - snums[i].state = QE_SNUM_STATE_USED; - snum = snums[i].num; - break; - } + i = find_first_zero_bit(snum_state, qe_num_of_snum); + if (i < qe_num_of_snum) { + set_bit(i, snum_state); + snum = snums[i]; } spin_unlock_irqrestore(&qe_lock, flags); @@ -343,14 +329,9 @@ EXPORT_SYMBOL(qe_get_snum); void qe_put_snum(u8 snum) { - int i; - - for (i = 0; i < qe_num_of_snum; i++) { - if (snums[i].num == snum) { - snums[i].state = QE_SNUM_STATE_FREE; - break; - } - } + const u8 *p = memchr(snums, snum, qe_num_of_snum); + if (p) + clear_bit(p - snums, snum_state); } EXPORT_SYMBOL(qe_put_snum);
The current array of struct qe_snum use 256*4 bytes for just keeping track of the free/used state of each index, and the struct layout means there's another 768 bytes of padding. If we just unzip that structure, the array of snum values just use 256 bytes, while the free/inuse state can be tracked in a 32 byte bitmap. So this reduces the .data footprint by 1760 bytes. It also serves as preparation for introducing another DT binding for specifying the snum values. Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk> --- drivers/soc/fsl/qe/qe.c | 43 ++++++++++++----------------------------- 1 file changed, 12 insertions(+), 31 deletions(-)