In each case below, I have followed the original semantics, but in drivers/atm/eni.c and drivers/atm/horizon.c, I have some doubts as to whether the original semantics is correct. In drivers/atm/eni.c, is the division intended to be by div or by div-1? In drivers/atm/horizon.c, it seems strange that "case round_down" is implemented by DIV_ROUND_UP, twice. The round_down and default (ie round_up) cases seem to be inversed.
--- From: Julia Lawall <[EMAIL PROTECTED]> The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) / (d)) but is perhaps more readable. An extract of the semantic patch that makes this change is as follows: (http://www.emn.fr/x-info/coccinelle/) // <smpl> @haskernel@ @@ #include <linux/kernel.h> @depends on haskernel@ expression n,d; @@ ( - (n + d - 1) / d + DIV_ROUND_UP(n,d) | - (n + (d - 1)) / d + DIV_ROUND_UP(n,d) ) @depends on haskernel@ expression n,d; @@ - DIV_ROUND_UP((n),d) + DIV_ROUND_UP(n,d) @depends on haskernel@ expression n,d; @@ - DIV_ROUND_UP(n,(d)) + DIV_ROUND_UP(n,d) // </smpl> Signed-off-by: Julia Lawall <[EMAIL PROTECTED]> --- diff -u -p a/drivers/atm/eni.c b/drivers/atm/eni.c --- a/drivers/atm/eni.c 2007-07-20 15:28:28.000000000 +0200 +++ b/drivers/atm/eni.c 2008-02-13 20:50:10.000000000 +0100 @@ -1270,7 +1270,7 @@ static int comp_tx(struct eni_dev *eni_d if (*pre < 3) (*pre)++; /* else fail later */ div = pre_div[*pre]*-*pcr; DPRINTK("max div %d\n",div); - *res = (TS_CLOCK+div-1)/div-1; + *res = DIV_ROUND_UP(TS_CLOCK, div)-1; } if (*res < 0) *res = 0; if (*res > MID_SEG_MAX_RATE) *res = MID_SEG_MAX_RATE; diff -u -p a/drivers/atm/horizon.c b/drivers/atm/horizon.c --- a/drivers/atm/horizon.c 2007-11-08 18:33:26.000000000 +0100 +++ b/drivers/atm/horizon.c 2008-02-13 20:50:13.000000000 +0100 @@ -635,7 +635,7 @@ static int make_rate (const hrz_dev * de // take care of rounding switch (r) { case round_down: - pre = (br+(c<<div)-1)/(c<<div); + pre = DIV_ROUND_UP(br, c<<div); // but p must be non-zero if (!pre) pre = 1; @@ -668,7 +668,7 @@ static int make_rate (const hrz_dev * de // take care of rounding switch (r) { case round_down: - pre = (br+(c<<div)-1)/(c<<div); + pre = DIV_ROUND_UP(br, c<<div); break; case round_nearest: pre = (br+(c<<div)/2)/(c<<div); @@ -698,7 +698,7 @@ got_it: if (bits) *bits = (div<<CLOCK_SELECT_SHIFT) | (pre-1); if (actual) { - *actual = (br + (pre<<div) - 1) / (pre<<div); + *actual = DIV_ROUND_UP(br, pre<<div); PRINTD (DBG_QOS, "actual rate: %u", *actual); } return 0; @@ -1967,7 +1967,7 @@ static int __devinit hrz_init (hrz_dev * // Set the max AAL5 cell count to be just enough to contain the // largest AAL5 frame that the user wants to receive wr_regw (dev, MAX_AAL5_CELL_COUNT_OFF, - (max_rx_size + ATM_AAL5_TRAILER + ATM_CELL_PAYLOAD - 1) / ATM_CELL_PAYLOAD); + DIV_ROUND_UP(max_rx_size + ATM_AAL5_TRAILER, ATM_CELL_PAYLOAD)); // Enable receive wr_regw (dev, RX_CONFIG_OFF, rd_regw (dev, RX_CONFIG_OFF) | RX_ENABLE); diff -u -p a/drivers/atm/zatm.c b/drivers/atm/zatm.c --- a/drivers/atm/zatm.c 2007-07-20 15:28:28.000000000 +0200 +++ b/drivers/atm/zatm.c 2008-02-14 07:26:36.000000000 +0100 @@ -496,8 +496,8 @@ static int open_rx_first(struct atm_vcc vcc->qos.rxtp.max_sdu = 65464; /* fix this - we may want to receive 64kB SDUs later */ - cells = (vcc->qos.rxtp.max_sdu+ATM_AAL5_TRAILER+ - ATM_CELL_PAYLOAD-1)/ATM_CELL_PAYLOAD; + cells = DIV_ROUND_UP(vcc->qos.rxtp.max_sdu+ATM_AAL5_TRAILER, + ATM_CELL_PAYLOAD); zatm_vcc->pool = pool_index(cells*ATM_CELL_PAYLOAD); } else { @@ -820,7 +820,7 @@ static int alloc_shaper(struct atm_dev * } else { i = 255; - m = (ATM_OC3_PCR*255+max-1)/max; + m = DIV_ROUND_UP(ATM_OC3_PCR*255, max); } } if (i > m) { -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
