- 22 Dec, 2010 27 commits
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Russell King authored
Provide common sched_clock() infrastructure for platforms to use to create a 64-bit ns based sched_clock() implementation from a counter running at a non-variable clock rate. This implementation is based upon maintaining an epoch for the counter and an epoch for the nanosecond time. When we desire a sched_clock() time, we calculate the number of counter ticks since the last epoch update, convert this to nanoseconds and add to the epoch nanoseconds. We regularly refresh these epochs within the counter wrap interval. We perform a similar calculation as above, and store the new epochs. We read and write the epochs in such a way that sched_clock() can easily (and locklessly) detect when an update is in progress, and repeat the loading of these constants when they're known not to be stable. The one caveat is that sched_clock() is not called in the middle of an update. We achieve that by disabling IRQs. Finally, if the clock rate is known at compile time, the counter to ns conversion factors can be specified, allowing sched_clock() to be tightly optimized. We ensure that these factors are correct by providing an initialization function which performs a run-time check. Acked-by: Peter Zijlstra <peterz@infradead.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Tested-by: Jamie Iles <jamie@jamieiles.com> Reviewed-by: Nicolas Pitre <nicolas.pitre@linaro.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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john stultz authored
Russell King reports: | On the ARM dev boards, we have a 32-bit counter running at 24MHz. Calling | clocks_calc_mult_shift(&mult, &shift, 24MHz, NSEC_PER_SEC, 60) gives | us a multiplier of 2796202666 and a shift of 26. | | Over a large counter delta, this produces an error - lets take a count | from 362976315 to 4280663372: | | (4280663372-362976315) * 2796202666 / 2^26 - (4280663372-362976315) * (1000/24) | => -38.91872422891230269990 | | Can we do better? | | (4280663372-362976315) * 2796202667 / 2^26 - (4280663372-362976315) * (1000/24) | 19.45936211449532822051 | | which is about twice as good as the 2796202666 multiplier. | | Looking at the equivalent divisions obtained, 2796202666 / 2^26 gives | 41.66666665673255920410ns per tick, whereas 2796202667 / 2^26 gives | 41.66666667163372039794ns. The actual value wanted is 1000/24 = | 41.66666666666666666666ns. Fix this by ensuring we round to nearest when calculating the multiplier. Signed-off-by: John Stultz <john.stultz@linaro.org> Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Tested-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
ftrace requires sched_clock() to be notrace. Ensure that all implementations are so marked. Also make sure that they include linux/sched.h Also ensure OMAP clocksource read functions are marked notrace as they're used for sched_clock() too. Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Tested-by: Will Deacon <will.deacon@arm.com> Tested-by: Mikael Pettersson <mikpe@it.uu.se> Tested-by: Eric Miao <eric.y.miao@gmail.com> Tested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Colin Cross authored
tegra_clocksource_read should not use cnt32_to_63, wrapping is already handled in the clocksource code. Move the cnt32_to_63 into the sched_clock function, and replace the use of clocksource mult and shift with a multiplication by 1000 to convert us to ns. Acked-by: John Stultz <johnstul@us.ibm.com> Acked-by: Linus Walleij <linus.walleij@stericsson.com> Tested-by: Olof Johansson <olof@lixom.net> Signed-off-by: Colin Cross <ccross@android.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Tested-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Nicolas Pitre <nico@fluxnic.net> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Viresh Kumar <viresh.kumar@st.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Wan zongshun <mcuos.com@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Linus Walleij <linus.walleij@stericsson.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Kukjin Kim <kgene.kim@samsung.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Tested-by: Eric Miao <eric.y.miao@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Tested-By: Jeff Ohlstein <johlstei@codeaurora.org> Acked-by: David Brown <davidb@codeaurora.org> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Tested-by: Mikael Pettersson <mikpe@it.uu.se> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Kevin Hilman <khilman@deeprootsystems.com> Tested-by: Kevin Hilman <khilman@deeprootsystems.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-By: Scott Branden <sbranden@broadcom.com> Acked-By: Jiandong Zheng <jdzheng@broadcom.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 19 Dec, 2010 2 commits
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Russell King authored
In d7e81c26 (clocksource: Add clocksource_register_hz/khz interface) new interfaces were added which simplify (and optimize) the selection of the divisor shift/mult constants. Switch over to using this new interface. Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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Russell King authored
Ensure that no interrupt is pending before registering the clock event device, and properly initialize the periodic tick in the ->set_mode callback. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
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- 26 Nov, 2010 3 commits
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- 25 Nov, 2010 5 commits
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Will Deacon authored
The ARM perf_event.c file contains all PMU backends and, as new PMUs are introduced, will continue to grow. This patch follows the example of x86 and splits the PMU implementations into separate files which are then #included back into the main file. Compile-time guards are added to each PMU file to avoid compiling in code that is not relevant for the version of the architecture which we are targetting. Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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Will Deacon authored
Currently, perf uses the PMU ID as an index into a string table to look up the name of a given PMU. This patch encodes the name of a PMU directly into the arm_pmu structure so that PMU-specific code can be factored out into separate files. Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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Will Deacon authored
In preparation for separating the PMU-specific code, this patch adds self-contained init functions to each PMU, therefore removing any PMU-specific knowledge from the PMU-agnostic init_hw_perf_events function. Acked-by: Jamie Iles <jamie@jamieiles.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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Will Deacon authored
Unlike other pmu functions, armv6pmu_pmu_stop is not declared static. This patch adds the missing keyword. Acked-by: Jamie Iles <jamie.iles@jamieiles.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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Will Deacon authored
The functions for mapping PMU events (perf, cache and raw) are common between all PMU types and differ only in the data on which they operate. This patch implements common definitions of these mapping functions and changes the arm_pmu struct to hold pointers to the data which they require. This is in anticipation of separating out the PMU-specific code into separate files. Acked-by: Jamie Iles <jamie.iles@jamieiles.com> Acked-by: Jean Pihet <j-pihet@ti.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
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- 24 Nov, 2010 3 commits
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git://git.kernel.org/pub/scm/linux/kernel/git/groeck/stagingLinus Torvalds authored
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/staging: hwmon: (lis3lv02d_i2c) Fix compile warnings hwmon: (i5k_amb) Fix compile warning
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git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xenLinus Torvalds authored
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen: xen: remove duplicated #include xen: x86/32: perform initial startup on initial_page_table
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git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tileLinus Torvalds authored
* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: arch/tile: fix memchr() not to dereference memory for zero length arch/tile: make glibc's sysconf(_SC_NPROCESSORS_CONF) work correctly arch/tile: fix rwlock so would-be write lockers don't block new readers
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