diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-13 20:49:41 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-08-13 20:49:41 +0300 |
| commit | b99cdfdf0b1c077dcb24c0053d36d4ff5832224e (patch) | |
| tree | 796bb158f58259b3f09c9fe874a9ff92658246fd /Documentation | |
| parent | d0daaeaf60143c02a2ef87f9f0703b63a0a7f8b3 (diff) | |
| parent | ea73a5c6929b9c7d30b7b424414645641cb7d1d9 (diff) | |
| download | linux-b99cdfdf0b1c077dcb24c0053d36d4ff5832224e.tar.xz | |
Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Thomas Gleixner:
"A large update to RCU:
Preparatory work for consolidating the RCU flavors:
- Introduce grace-period sequence numbers to the RCU-bh, RCU-preempt,
and RCU-sched flavors, replacing the old ->gpnum and ->completed
pair of fields.
This change allows lockless code to obtain the complete
grace-period state with a single READ_ONCE(), which is needed to
maintain tolerable lock contention during the upcoming
consolidation of the three RCU flavors.
Note that grace-period sequence numbers are already used by
rcu_barrier(), expedited RCU grace periods, and SRCU, and are thus
already heavily used and well-tested. Joel Fernandes contributed a
number of excellent fixes and improvements.
- Clean up some grace-period-reporting loose ends, including
improving the handling of quiescent states from offline CPUs and
fixing some false-positive WARN_ON_ONCE() invocations.
(Strictly speaking, the WARN_ON_ONCE() invocations were quite
correct, but their invariants were (harmlessly) violated by the
earlier sloppy handling of quiescent states from offline CPUs.)
In addition, improve grace-period forward-progress guarantees so as
to allow removal of fail-safe checks that required otherwise
needless lock acquisitions. Finally, add more diagnostics to help
debug the upcoming consolidation of the RCU-bh, RCU-preempt, and
RCU-sched flavors.
The rest:
- SRCU updates
- Updates to rcutorture and associated scripting.
- The usual pile of miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (118 commits)
rcutorture: Fix rcu_barrier successes counter
rcutorture: Add support to detect if boost kthread prio is too low
rcutorture: Use monotonic timestamp for stall detection
rcutorture: Make boost test more robust
rcutorture: Disable RT throttling for boost tests
rcutorture: Emphasize testing of single reader protection type
rcutorture: Handle extended read-side critical sections
rcutorture: Make rcu_torture_timer() use rcu_torture_one_read()
rcutorture: Use per-CPU random state for rcu_torture_timer()
rcutorture: Use atomic increment for n_rcu_torture_timers
rcutorture: Extract common code from rcu_torture_reader()
rcuperf: Remove unused torturing_tasks() function
rcu: Remove rcutorture test version and sequence number
rcutorture: Change units of onoff_interval to jiffies
rcu: Assign higher prio to RCU threads if rcutorture is built-in
rculist: Improve documentation for list_for_each_entry_from_rcu()
srcu: Add grace-period number to rcutorture statistics printout
rcu: Print stall-warning NMI dyntick state in hexadecimal
MAINTAINERS: Update RCU, SRCU, and TORTURE-TEST entries
rcu: Make rcu_seq_diff() more exact
...
Diffstat (limited to 'Documentation')
10 files changed, 332 insertions, 298 deletions
diff --git a/Documentation/RCU/Design/Data-Structures/Data-Structures.html b/Documentation/RCU/Design/Data-Structures/Data-Structures.html index 6c06e10bd04b..f5120a00f511 100644 --- a/Documentation/RCU/Design/Data-Structures/Data-Structures.html +++ b/Documentation/RCU/Design/Data-Structures/Data-Structures.html @@ -380,31 +380,26 @@ and therefore need no protection. as follows: <pre> - 1 unsigned long gpnum; - 2 unsigned long completed; + 1 unsigned long gp_seq; </pre> <p>RCU grace periods are numbered, and -the <tt>->gpnum</tt> field contains the number of the grace -period that started most recently. -The <tt>->completed</tt> field contains the number of the -grace period that completed most recently. -If the two fields are equal, the RCU grace period that most recently -started has already completed, and therefore the corresponding -flavor of RCU is idle. -If <tt>->gpnum</tt> is one greater than <tt>->completed</tt>, -then <tt>->gpnum</tt> gives the number of the current RCU -grace period, which has not yet completed. -Any other combination of values indicates that something is broken. -These two fields are protected by the root <tt>rcu_node</tt>'s +the <tt>->gp_seq</tt> field contains the current grace-period +sequence number. +The bottom two bits are the state of the current grace period, +which can be zero for not yet started or one for in progress. +In other words, if the bottom two bits of <tt>->gp_seq</tt> are +zero, the corresponding flavor of RCU is idle. +Any other value in the bottom two bits indicates that something is broken. +This field is protected by the root <tt>rcu_node</tt> structure's <tt>->lock</tt> field. -</p><p>There are <tt>->gpnum</tt> and <tt>->completed</tt> fields +</p><p>There are <tt>->gp_seq</tt> fields in the <tt>rcu_node</tt> and <tt>rcu_data</tt> structures as well. The fields in the <tt>rcu_state</tt> structure represent the -most current values, and those of the other structures are compared -in order to detect the start of a new grace period in a distributed +most current value, and those of the other structures are compared +in order to detect the beginnings and ends of grace periods in a distributed fashion. The values flow from <tt>rcu_state</tt> to <tt>rcu_node</tt> (down the tree from the root to the leaves) to <tt>rcu_data</tt>. @@ -512,27 +507,47 @@ than to be heisenbugged out of existence. as follows: <pre> - 1 unsigned long gpnum; - 2 unsigned long completed; + 1 unsigned long gp_seq; + 2 unsigned long gp_seq_needed; </pre> -<p>These fields are the counterparts of the fields of the same name in -the <tt>rcu_state</tt> structure. -They each may lag up to one behind their <tt>rcu_state</tt> -counterparts. -If a given <tt>rcu_node</tt> structure's <tt>->gpnum</tt> and -<tt>->complete</tt> fields are equal, then this <tt>rcu_node</tt> +<p>The <tt>rcu_node</tt> structures' <tt>->gp_seq</tt> fields are +the counterparts of the field of the same name in the <tt>rcu_state</tt> +structure. +They each may lag up to one step behind their <tt>rcu_state</tt> +counterpart. +If the bottom two bits of a given <tt>rcu_node</tt> structure's +<tt>->gp_seq</tt> field is zero, then this <tt>rcu_node</tt> structure believes that RCU is idle. -Otherwise, as with the <tt>rcu_state</tt> structure, -the <tt>->gpnum</tt> field will be one greater than the -<tt>->complete</tt> fields, with <tt>->gpnum</tt> -indicating which grace period this <tt>rcu_node</tt> believes -is still being waited for. +</p><p>The <tt>>gp_seq</tt> field of each <tt>rcu_node</tt> +structure is updated at the beginning and the end +of each grace period. + +<p>The <tt>->gp_seq_needed</tt> fields record the +furthest-in-the-future grace period request seen by the corresponding +<tt>rcu_node</tt> structure. The request is considered fulfilled when +the value of the <tt>->gp_seq</tt> field equals or exceeds that of +the <tt>->gp_seq_needed</tt> field. -</p><p>The <tt>>gpnum</tt> field of each <tt>rcu_node</tt> -structure is updated at the beginning -of each grace period, and the <tt>->completed</tt> fields are -updated at the end of each grace period. +<table> +<tr><th> </th></tr> +<tr><th align="left">Quick Quiz:</th></tr> +<tr><td> + Suppose that this <tt>rcu_node</tt> structure doesn't see + a request for a very long time. + Won't wrapping of the <tt>->gp_seq</tt> field cause + problems? +</td></tr> +<tr><th align="left">Answer:</th></tr> +<tr><td bgcolor="#ffffff"><font color="ffffff"> + No, because if the <tt>->gp_seq_needed</tt> field lags behind the + <tt>->gp_seq</tt> field, the <tt>->gp_seq_needed</tt> field + will be updated at the end of the grace period. + Modulo-arithmetic comparisons therefore will always get the + correct answer, even with wrapping. +</font></td></tr> +<tr><td> </td></tr> +</table> <h5>Quiescent-State Tracking</h5> @@ -626,9 +641,8 @@ normal and expedited grace periods, respectively. </ol> <p><font color="ffffff">So the locking is absolutely required in - order to coordinate - clearing of the bits with the grace-period numbers in - <tt>->gpnum</tt> and <tt>->completed</tt>. + order to coordinate clearing of the bits with updating of the + grace-period sequence number in <tt>->gp_seq</tt>. </font></td></tr> <tr><td> </td></tr> </table> @@ -1038,15 +1052,15 @@ out any <tt>rcu_data</tt> structure for which this flag is not set. as follows: <pre> - 1 unsigned long completed; - 2 unsigned long gpnum; + 1 unsigned long gp_seq; + 2 unsigned long gp_seq_needed; 3 bool cpu_no_qs; 4 bool core_needs_qs; 5 bool gpwrap; 6 unsigned long rcu_qs_ctr_snap; </pre> -<p>The <tt>completed</tt> and <tt>gpnum</tt> +<p>The <tt>->gp_seq</tt> and <tt>->gp_seq_needed</tt> fields are the counterparts of the fields of the same name in the <tt>rcu_state</tt> and <tt>rcu_node</tt> structures. They may each lag up to one behind their <tt>rcu_node</tt> @@ -1054,15 +1068,9 @@ counterparts, but in <tt>CONFIG_NO_HZ_IDLE</tt> and <tt>CONFIG_NO_HZ_FULL</tt> kernels can lag arbitrarily far behind for CPUs in dyntick-idle mode (but these counters will catch up upon exit from dyntick-idle mode). -If a given <tt>rcu_data</tt> structure's <tt>->gpnum</tt> and -<tt>->complete</tt> fields are equal, then this <tt>rcu_data</tt> +If the lower two bits of a given <tt>rcu_data</tt> structure's +<tt>->gp_seq</tt> are zero, then this <tt>rcu_data</tt> structure believes that RCU is idle. -Otherwise, as with the <tt>rcu_state</tt> and <tt>rcu_node</tt> -structure, -the <tt>->gpnum</tt> field will be one greater than the -<tt>->complete</tt> fields, with <tt>->gpnum</tt> -indicating which grace period this <tt>rcu_data</tt> believes -is still being waited for. <table> <tr><th> </th></tr> @@ -1070,13 +1078,13 @@ is still being waited for. <tr><td> All this replication of the grace period numbers can only cause massive confusion. - Why not just keep a global pair of counters and be done with it??? + Why not just keep a global sequence number and be done with it??? </td></tr> <tr><th align="left">Answer:</th></tr> <tr><td bgcolor="#ffffff"><font color="ffffff"> - Because if there was only a single global pair of grace-period + Because if there was only a single global sequence numbers, there would need to be a single global lock to allow - safely accessing and updating them. + safely accessing and updating it. And if we are not going to have a single global lock, we need to carefully manage the numbers on a per-node basis. Recall from the answer to a previous Quick Quiz that the consequences @@ -1091,8 +1099,8 @@ CPU has not yet passed through a quiescent state, while the <tt>->core_needs_qs</tt> flag indicates that the RCU core needs a quiescent state from the corresponding CPU. The <tt>->gpwrap</tt> field indicates that the corresponding -CPU has remained idle for so long that the <tt>completed</tt> -and <tt>gpnum</tt> counters are in danger of overflow, which +CPU has remained idle for so long that the +<tt>gp_seq</tt> counter is in danger of overflow, which will cause the CPU to disregard the values of its counters on its next exit from idle. Finally, the <tt>rcu_qs_ctr_snap</tt> field is used to detect @@ -1130,10 +1138,10 @@ The CPU advances the callbacks in its <tt>rcu_data</tt> structure whenever it notices that another RCU grace period has completed. The CPU detects the completion of an RCU grace period by noticing that the value of its <tt>rcu_data</tt> structure's -<tt>->completed</tt> field differs from that of its leaf +<tt>->gp_seq</tt> field differs from that of its leaf <tt>rcu_node</tt> structure. Recall that each <tt>rcu_node</tt> structure's -<tt>->completed</tt> field is updated at the end of each +<tt>->gp_seq</tt> field is updated at the beginnings and ends of each grace period. <p> diff --git a/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html index 8651b0b4fd79..a346ce0116eb 100644 --- a/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html +++ b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html @@ -357,7 +357,7 @@ parts, starting in this section with the various phases of grace-period initialization. <p>The first ordering-related grace-period initialization action is to -increment the <tt>rcu_state</tt> structure's <tt>->gpnum</tt> +advance the <tt>rcu_state</tt> structure's <tt>->gp_seq</tt> grace-period-number counter, as shown below: </p><p><img src="TreeRCU-gp-init-1.svg" alt="TreeRCU-gp-init-1.svg" width="75%"> @@ -388,7 +388,7 @@ its last CPU and if the next <tt>rcu_node</tt> structure has no online CPUs). <p>The final <tt>rcu_gp_init()</tt> pass through the <tt>rcu_node</tt> tree traverses breadth-first, setting each <tt>rcu_node</tt> structure's -<tt>->gpnum</tt> field to the newly incremented value from the +<tt>->gp_seq</tt> field to the newly advanced value from the <tt>rcu_state</tt> structure, as shown in the following diagram. </p><p><img src="TreeRCU-gp-init-3.svg" alt="TreeRCU-gp-init-1.svg" width="75%"> @@ -398,9 +398,9 @@ tree traverses breadth-first, setting each <tt>rcu_node</tt> structure's to notice that a new grace period has started, as described in the next section. But because the grace-period kthread started the grace period at the -root (with the increment of the <tt>rcu_state</tt> structure's -<tt>->gpnum</tt> field) before setting each leaf <tt>rcu_node</tt> -structure's <tt>->gpnum</tt> field, each CPU's observation of +root (with the advancing of the <tt>rcu_state</tt> structure's +<tt>->gp_seq</tt> field) before setting each leaf <tt>rcu_node</tt> +structure's <tt>->gp_seq</tt> field, each CPU's observation of the start of the grace period will happen after the actual start of the grace period. @@ -466,7 +466,7 @@ section that the grace period must wait on. <tr><td> But a RCU read-side critical section might have started after the beginning of the grace period - (the <tt>->gpnum++</tt> from earlier), so why should + (the advancing of <tt>->gp_seq</tt> from earlier), so why should the grace period wait on such a critical section? </td></tr> <tr><th align="left">Answer:</th></tr> @@ -609,10 +609,8 @@ states outstanding from other CPUs. <h4><a name="Grace-Period Cleanup">Grace-Period Cleanup</a></h4> <p>Grace-period cleanup first scans the <tt>rcu_node</tt> tree -breadth-first setting all the <tt>->completed</tt> fields equal -to the number of the newly completed grace period, then it sets -the <tt>rcu_state</tt> structure's <tt>->completed</tt> field, -again to the number of the newly completed grace period. +breadth-first advancing all the <tt>->gp_seq</tt> fields, then it +advances the <tt>rcu_state</tt> structure's <tt>->gp_seq</tt> field. The ordering effects are shown below: </p><p><img src="TreeRCU-gp-cleanup.svg" alt="TreeRCU-gp-cleanup.svg" width="75%"> @@ -634,7 +632,7 @@ grace-period cleanup is complete, the next grace period can begin. CPU has reported its quiescent state, but it may be some milliseconds before RCU becomes aware of this. The latest reasonable candidate is once the <tt>rcu_state</tt> - structure's <tt>->completed</tt> field has been updated, + structure's <tt>->gp_seq</tt> field has been updated, but it is quite possible that some CPUs have already completed phase two of their updates by that time. In short, if you are going to work with RCU, you need to @@ -647,7 +645,7 @@ grace-period cleanup is complete, the next grace period can begin. <h4><a name="Callback Invocation">Callback Invocation</a></h4> <p>Once a given CPU's leaf <tt>rcu_node</tt> structure's -<tt>->completed</tt> field has been updated, that CPU can begin +<tt>->gp_seq</tt> field has been updated, that CPU can begin invoking its RCU callbacks that were waiting for this grace period to end. These callbacks are identified by <tt>rcu_advance_cbs()</tt>, diff --git a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-cleanup.svg b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-cleanup.svg index 754f426b297a..bf84fbab27ee 100644 --- a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-cleanup.svg +++ b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-cleanup.svg @@ -384,11 +384,11 @@ inkscape:window-height="1144" id="namedview208" showgrid="true" - inkscape:zoom="0.70710678" - inkscape:cx="617.89017" - inkscape:cy="542.52419" - inkscape:window-x="86" - inkscape:window-y="28" + inkscape:zoom="0.78716603" + inkscape:cx="513.06403" + inkscape:cy="623.1214" + inkscape:window-x="102" + inkscape:window-y="38" inkscape:window-maximized="0" inkscape:current-layer="g3188-3" fit-margin-top="5" @@ -417,13 +417,15 @@ id="g3188"> <text xml:space="preserve" - x="3199.1516" + x="3145.9592" y="13255.592" font-style="normal" font-weight="bold" font-size="192" id="text202" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">->completed = ->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3143">rcu_seq_end(&rnp->gp_seq)</tspan></text> <g id="g3107" transform="translate(947.90548,11584.029)"> @@ -502,13 +504,15 @@ </g> <text xml:space="preserve" - x="5324.5371" - y="15414.598" + x="5264.4731" + y="15428.84" font-style="normal" font-weight="bold" font-size="192" - id="text202-753" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-7" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-5">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g style="fill:none;stroke-width:0.025in" @@ -547,15 +551,6 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-6-0">Leaf</tspan></text> - <text - xml:space="preserve" - x="7479.5796" - y="17699.943" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-9" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> <path sodipodi:nodetypes="cc" inkscape:connector-curvature="0" @@ -566,15 +561,6 @@ style="fill:none;stroke-width:0.025in" transform="translate(-737.93887,7732.6672)" id="g3188-3"> - <text - xml:space="preserve" - x="3225.7478" - y="13175.802" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-60" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">rsp->completed =</text> <g id="g3107-62" transform="translate(947.90548,11584.029)"> @@ -607,15 +593,6 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-7">Root</tspan></text> - <text - xml:space="preserve" - x="3225.7478" - y="13390.038" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-60-3" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"> rnp->completed</text> <flowRoot xml:space="preserve" id="flowRoot3356" @@ -627,7 +604,18 @@ height="63.63961" x="332.34018" y="681.87292" /></flowRegion><flowPara - id="flowPara3362" /></flowRoot> </g> + id="flowPara3362" /></flowRoot> <text + xml:space="preserve" + x="3156.6121" + y="13317.754" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-6" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-0">rcu_seq_end(&rsp->gp_seq)</tspan></text> + </g> <g style="fill:none;stroke-width:0.025in" transform="translate(-858.40227,7769.0342)" @@ -859,6 +847,17 @@ id="path3414-8-3-6-6" inkscape:connector-curvature="0" sodipodi:nodetypes="cc" /> + <text + xml:space="preserve" + x="7418.769" + y="17646.104" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-70" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-93">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g transform="translate(-1642.5377,-11611.245)" @@ -887,13 +886,15 @@ </g> <text xml:space="preserve" - x="5327.3057" + x="5274.1133" y="15428.84" font-style="normal" font-weight="bold" font-size="192" id="text202-36" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g transform="translate(-151.71746,-11647.612)" @@ -972,13 +973,15 @@ id="tspan3104-6-5-6-0-92">Leaf</tspan></text> <text xml:space="preserve" - x="7486.4907" - y="17670.119" + x="7408.5918" + y="17619.504" font-style="normal" font-weight="bold" font-size="192" - id="text202-6" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-2" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-9">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g transform="translate(-6817.1997,-11647.612)" @@ -1019,13 +1022,15 @@ id="tspan3104-6-5-6-0-1">Leaf</tspan></text> <text xml:space="preserve" - x="7474.1382" - y="17688.926" + x="7416.8003" + y="17619.504" font-style="normal" font-weight="bold" font-size="192" - id="text202-5" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-3" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-56">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <path style="fill:none;stroke:#000000;stroke-width:13.29812908px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;marker-end:url(#Arrow2Lend)" @@ -1059,15 +1064,6 @@ id="path3414-8-3-6" inkscape:connector-curvature="0" sodipodi:nodetypes="cc" /> - <text - xml:space="preserve" - x="7318.9653" - y="6031.6353" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-2" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> <g style="fill:none;stroke-width:0.025in" id="g4504-3-9" @@ -1123,4 +1119,15 @@ id="path3134-9-0-3-5" d="m 6875.6003,15833.906 1595.7755,0" style="fill:none;stroke:#969696;stroke-width:53.19251633;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-opacity:1;stroke-dasharray:none;marker-end:url(#Arrow1Send-36)" /> + <text + xml:space="preserve" + x="7275.2612" + y="5971.8916" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-1" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-2">rcu_seq_end(&rnp->gp_seq)</tspan></text> </svg> diff --git a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-1.svg b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-1.svg index 0161262904ec..8c207550818f 100644 --- a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-1.svg +++ b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-1.svg @@ -272,13 +272,13 @@ inkscape:window-height="1144" id="namedview208" showgrid="true" - inkscape:zoom="0.70710678" - inkscape:cx="617.89019" - inkscape:cy="636.57143" - inkscape:window-x="697" + inkscape:zoom="2.6330492" + inkscape:cx="524.82797" + inkscape:cy="519.31194" + inkscape:window-x="79" inkscape:window-y="28" inkscape:window-maximized="0" - inkscape:current-layer="svg2" + inkscape:current-layer="g3188" fit-margin-top="5" fit-margin-right="5" fit-margin-left="5" @@ -305,13 +305,15 @@ id="g3188"> <text xml:space="preserve" - x="3305.5364" + x="3119.363" y="13255.592" font-style="normal" font-weight="bold" font-size="192" id="text202" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">rsp->gpnum++</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3071">rcu_seq_start(rsp->gp_seq)</tspan></text> <g id="g3107" transform="translate(947.90548,11584.029)"> diff --git a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-3.svg b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-3.svg index de6ecc51b00e..d24d7d555dbc 100644 --- a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-3.svg +++ b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp-init-3.svg @@ -19,7 +19,7 @@ id="svg2" version="1.1" inkscape:version="0.48.4 r9939" - sodipodi:docname="TreeRCU-gp-init-2.svg"> + sodipodi:docname="TreeRCU-gp-init-3.svg"> <metadata id="metadata212"> <rdf:RDF> @@ -257,18 +257,22 @@ inkscape:window-width="1087" inkscape:window-height="1144" id="namedview208" - showgrid="false" - inkscape:zoom="0.70710678" + showgrid="true" + inkscape:zoom="0.68224756" inkscape:cx="617.89019" inkscape:cy="625.84293" - inkscape:window-x="697" + inkscape:window-x="54" inkscape:window-y="28" inkscape:window-maximized="0" - inkscape:current-layer="svg2" + inkscape:current-layer="g3153" fit-margin-top="5" fit-margin-right="5" fit-margin-left="5" - fit-margin-bottom="5" /> + fit-margin-bottom="5"> + <inkscape:grid + type="xygrid" + id="grid3090" /> + </sodipodi:namedview> <path sodipodi:nodetypes="cccccccccccccccccccccccc" inkscape:connector-curvature="0" @@ -281,13 +285,13 @@ id="g3188"> <text xml:space="preserve" - x="3305.5364" + x="3145.9592" y="13255.592" font-style="normal" font-weight="bold" font-size="192" id="text202" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">->gp_seq = rsp->gp_seq</text> <g id="g3107" transform="translate(947.90548,11584.029)"> @@ -366,13 +370,13 @@ </g> <text xml:space="preserve" - x="5392.3345" - y="15407.104" + x="5253.6904" + y="15407.032" font-style="normal" font-weight="bold" font-size="192" id="text202-6" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g style="fill:none;stroke-width:0.025in" @@ -413,13 +417,13 @@ id="tspan3104-6-5-6-0">Leaf</tspan></text> <text xml:space="preserve" - x="7536.4883" - y="17640.934" + x="7415.4365" + y="17670.572" font-style="normal" font-weight="bold" font-size="192" id="text202-9" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-1642.5375,-11610.962)" @@ -448,13 +452,13 @@ </g> <text xml:space="preserve" - x="5378.4146" - y="15436.927" + x="5258.0688" + y="15412.313" font-style="normal" font-weight="bold" font-size="192" id="text202-3" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-151.71726,-11647.329)" @@ -533,13 +537,13 @@ id="tspan3104-6-5-6-0-92">Leaf</tspan></text> <text xml:space="preserve" - x="7520.1294" - y="17673.639" + x="7405.2607" + y="17670.572" font-style="normal" font-weight="bold" font-size="192" id="text202-35" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-6817.1998,-11647.329)" @@ -580,13 +584,13 @@ id="tspan3104-6-5-6-0-1">Leaf</tspan></text> <text xml:space="preserve" - x="7521.4663" - y="17666.062" + x="7413.4688" + y="17670.566" font-style="normal" font-weight="bold" font-size="192" id="text202-75" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <path style="fill:none;stroke:#000000;stroke-width:13.29812908px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;marker-end:url(#Arrow2Lend)" @@ -622,11 +626,11 @@ sodipodi:nodetypes="cc" /> <text xml:space="preserve" - x="7370.856" - y="5997.5972" + x="7271.9297" + y="6023.2412" font-style="normal" font-weight="bold" font-size="192" id="text202-62" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </svg> diff --git a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp.svg b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp.svg index b13b7b01bb3a..acd73c7ad0f4 100644 --- a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp.svg +++ b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-gp.svg @@ -1070,13 +1070,13 @@ inkscape:window-height="1144" id="namedview208" showgrid="true" - inkscape:zoom="0.6004608" - inkscape:cx="826.65969" - inkscape:cy="483.3047" - inkscape:window-x="66" - inkscape:window-y="28" + inkscape:zoom="0.81932583" + inkscape:cx="840.45848" + inkscape:cy="5052.4242" + inkscape:window-x="787" + inkscape:window-y="24" inkscape:window-maximized="0" - inkscape:current-layer="svg2" + inkscape:current-layer="g4" fit-margin-top="5" fit-margin-right="5" fit-margin-left="5" @@ -1543,15 +1543,6 @@ style="fill:none;stroke-width:0.025in" transform="translate(1749.0282,658.72243)" id="g3188"> - <text - xml:space="preserve" - x="3305.5364" - y="13255.592" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-5" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">rsp->gpnum++</text> <g id="g3107-62" transform="translate(947.90548,11584.029)"> @@ -1584,6 +1575,17 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-7">Root</tspan></text> + <text + xml:space="preserve" + x="3137.9988" + y="13271.316" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-626" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3071">rcu_seq_start(rsp->gp_seq)</tspan></text> </g> <rect ry="0" @@ -2318,15 +2320,6 @@ style="fill:none;stroke-width:0.025in" transform="translate(1739.0986,17188.625)" id="g3188-6"> - <text - xml:space="preserve" - x="3305.5364" - y="13255.592" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-1" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">->gpnum = rsp->gpnum</text> <g id="g3107-5" transform="translate(947.90548,11584.029)"> @@ -2359,6 +2352,15 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-1">Root</tspan></text> + <text + xml:space="preserve" + x="3147.9268" + y="13240.524" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-1" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g style="fill:none;stroke-width:0.025in" @@ -2387,13 +2389,13 @@ </g> <text xml:space="preserve" - x="5392.3345" - y="15407.104" + x="5263.1094" + y="15411.646" font-style="normal" font-weight="bold" font-size="192" - id="text202-6-7" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + id="text202-92" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g style="fill:none;stroke-width:0.025in" @@ -2434,13 +2436,13 @@ id="tspan3104-6-5-6-0-94">Leaf</tspan></text> <text xml:space="preserve" - x="7536.4883" - y="17640.934" + x="7417.4053" + y="17655.502" font-style="normal" font-weight="bold" font-size="192" - id="text202-9" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + id="text202-759" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-2353.8462,17224.992)" @@ -2469,13 +2471,13 @@ </g> <text xml:space="preserve" - x="5378.4146" - y="15436.927" + x="5246.1548" + y="15411.648" font-style="normal" font-weight="bold" font-size="192" - id="text202-3" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + id="text202-87" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-863.02613,17188.625)" @@ -2554,13 +2556,13 @@ id="tspan3104-6-5-6-0-92-6">Leaf</tspan></text> <text xml:space="preserve" - x="7520.1294" - y="17673.639" + x="7433.8257" + y="17682.098" font-style="normal" font-weight="bold" font-size="192" - id="text202-35" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + id="text202-2" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <g transform="translate(-7528.5085,17188.625)" @@ -2601,13 +2603,13 @@ id="tspan3104-6-5-6-0-1-8">Leaf</tspan></text> <text xml:space="preserve" - x="7521.4663" - y="17666.062" + x="7415.4404" + y="17682.098" font-style="normal" font-weight="bold" font-size="192" - id="text202-75-1" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> + id="text202-0" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> <path style="fill:none;stroke:#000000;stroke-width:13.29812813px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;marker-end:url(#Arrow2Lend)" @@ -2641,15 +2643,6 @@ id="path3414-8-3-6-4" inkscape:connector-curvature="0" sodipodi:nodetypes="cc" /> - <text - xml:space="preserve" - x="6659.5469" - y="34833.551" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-62" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gpnum = rsp->gpnum</text> <path sodipodi:nodetypes="ccc" inkscape:connector-curvature="0" @@ -3844,7 +3837,7 @@ font-weight="bold" font-size="192" id="text202-6-6-5" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rdp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rdp->gp_seq</text> <text xml:space="preserve" x="5035.4155" @@ -4284,15 +4277,6 @@ style="fill:none;stroke-width:0.025in" transform="translate(1874.038,53203.538)" id="g3188-7"> - <text - xml:space="preserve" - x="3199.1516" - y="13255.592" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-82" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;font-family:Courier">->completed = ->gpnum</text> <g id="g3107-53" transform="translate(947.90548,11584.029)"> @@ -4325,6 +4309,17 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-19">Root</tspan></text> + <text + xml:space="preserve" + x="3175.896" + y="13240.11" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-3" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <rect ry="0" @@ -4371,13 +4366,15 @@ </g> <text xml:space="preserve" - x="5324.5371" - y="15414.598" + x="5264.4829" + y="15411.231" font-style="normal" font-weight="bold" font-size="192" - id="text202-753" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-7" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-5">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g style="fill:none;stroke-width:0.025in" @@ -4412,30 +4409,12 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-6-0-4">Leaf</tspan></text> - <text - xml:space="preserve" - x="10084.225" - y="70903.312" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-9-0" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> <path sodipodi:nodetypes="ccc" inkscape:connector-curvature="0" id="path3134-9-0-3-9" d="m 6315.6122,72629.054 -20.9533,8108.684 1648.968,0" style="fill:none;stroke:#969696;stroke-width:53.19251251;stroke-linecap:butt;stroke-linejoin:miter;stroke-miterlimit:4;stroke-opacity:1;stroke-dasharray:none;marker-end:url(#Arrow1Send)" /> - <text - xml:space="preserve" - x="5092.4683" - y="74111.672" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-60" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rsp->completed =</text> <g style="fill:none;stroke-width:0.025in" id="g3107-62-6" @@ -4469,15 +4448,6 @@ sodipodi:linespacing="125%"><tspan style="font-size:159.57754517px;font-style:normal;font-variant:normal;font-weight:normal;font-stretch:normal;text-align:start;line-height:125%;writing-mode:lr-tb;text-anchor:start;font-family:Liberation Sans;-inkscape-font-specification:Liberation Sans" id="tspan3104-6-5-7-7">Root</tspan></text> - <text - xml:space="preserve" - x="5092.4683" - y="74325.906" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-60-3" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"> rnp->completed</text> <g style="fill:none;stroke-width:0.025in" transform="translate(1746.2528,60972.572)" @@ -4736,13 +4706,15 @@ </g> <text xml:space="preserve" - x="5327.3057" - y="15428.84" + x="5274.1216" + y="15411.231" font-style="normal" font-weight="bold" font-size="192" id="text202-36" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-6">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g transform="translate(-728.08545,53203.538)" @@ -4821,13 +4793,15 @@ id="tspan3104-6-5-6-0-92-5">Leaf</tspan></text> <text xml:space="preserve" - x="7486.4907" - y="17670.119" + x="7435.1987" + y="17708.281" font-style="normal" font-weight="bold" font-size="192" - id="text202-6-2" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-9" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-1">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <g transform="translate(-7393.5687,53203.538)" @@ -4868,13 +4842,15 @@ id="tspan3104-6-5-6-0-1-5">Leaf</tspan></text> <text xml:space="preserve" - x="7474.1382" - y="17688.926" + x="7416.8125" + y="17708.281" font-style="normal" font-weight="bold" font-size="192" - id="text202-5-1" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> + id="text202-36-35" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-62">rcu_seq_end(&rnp->gp_seq)</tspan></text> </g> <path style="fill:none;stroke:#000000;stroke-width:13.29812813px;stroke-linecap:butt;stroke-linejoin:miter;stroke-opacity:1;marker-end:url(#Arrow2Lend)" @@ -4908,15 +4884,6 @@ id="path3414-8-3-6-67" inkscape:connector-curvature="0" sodipodi:nodetypes="cc" /> - <text - xml:space="preserve" - x="6742.6001" - y="70882.617" - font-style="normal" - font-weight="bold" - font-size="192" - id="text202-2" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->completed = ->gpnum</text> <g style="fill:none;stroke-width:0.025in" id="g4504-3-9-6" @@ -5131,5 +5098,47 @@ font-size="192" id="text202-7-9-6-6-7" style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rcu_do_batch()</text> + <text + xml:space="preserve" + x="6698.9019" + y="70885.211" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-2" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-7">rcu_seq_end(&rnp->gp_seq)</tspan></text> + <text + xml:space="preserve" + x="10023.457" + y="70885.234" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-0" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-9">rcu_seq_end(&rnp->gp_seq)</tspan></text> + <text + xml:space="preserve" + x="5023.3389" + y="74209.773" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-36-36" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier"><tspan + style="font-size:172.87567139px" + id="tspan3166-0">rcu_seq_end(&rsp->gp_seq)</tspan></text> + <text + xml:space="preserve" + x="6562.5884" + y="34870.727" + font-style="normal" + font-weight="bold" + font-size="192" + id="text202-3" + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">->gp_seq = rsp->gp_seq</text> </g> </svg> diff --git a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-qs.svg b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-qs.svg index de3992f4cbe1..149bec2a4493 100644 --- a/Documentation/RCU/Design/Memory-Ordering/TreeRCU-qs.svg +++ b/Documentation/RCU/Design/Memory-Ordering/TreeRCU-qs.svg @@ -300,13 +300,13 @@ inkscape:window-height="1144" id="namedview208" showgrid="true" - inkscape:zoom="0.70710678" - inkscape:cx="616.47598" - inkscape:cy="595.41964" - inkscape:window-x="813" + inkscape:zoom="0.96484375" + inkscape:cx="507.0191" + inkscape:cy="885.62207" + inkscape:window-x="47" inkscape:window-y="28" inkscape:window-maximized="0" - inkscape:current-layer="g4405" + inkscape:current-layer="g3115" fit-margin-top="5" fit-margin-right="5" fit-margin-left="5" @@ -710,7 +710,7 @@ font-weight="bold" font-size="192" id="text202-6-6" - style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rdp->gpnum</text> + style="font-size:192px;font-style:normal;font-weight:bold;text-anchor:start;fill:#000000;stroke-width:0.025in;font-family:Courier">rdp->gp_seq</text> <text xml:space="preserve" x="5035.4155" diff --git a/Documentation/RCU/stallwarn.txt b/Documentation/RCU/stallwarn.txt index 4259f95c3261..f99cf11b314b 100644 --- a/Documentation/RCU/stallwarn.txt +++ b/Documentation/RCU/stallwarn.txt @@ -172,7 +172,7 @@ it will print a message similar to the following: INFO: rcu_sched detected stalls on CPUs/tasks: 2-...: (3 GPs behind) idle=06c/0/0 softirq=1453/1455 fqs=0 16-...: (0 ticks this GP) idle=81c/0/0 softirq=764/764 fqs=0 - (detected by 32, t=2603 jiffies, g=7073, c=7072, q=625) + (detected by 32, t=2603 jiffies, g=7075, q=625) This message indicates that CPU 32 detected that CPUs 2 and 16 were both causing stalls, and that the stall was affecting RCU-sched. This message @@ -215,11 +215,10 @@ CPU since the last time that this CPU noted the beginning of a grace period. The "detected by" line indicates which CPU detected the stall (in this -case, CPU 32), how many jiffies have elapsed since the start of the -grace period (in this case 2603), the number of the last grace period -to start and to complete (7073 and 7072, respectively), and an estimate -of the total number of RCU callbacks queued across all CPUs (625 in -this case). +case, CPU 32), how many jiffies have elapsed since the start of the grace +period (in this case 2603), the grace-period sequence number (7075), and +an estimate of the total number of RCU callbacks queued across all CPUs +(625 in this case). In kernels with CONFIG_RCU_FAST_NO_HZ, more information is printed for each CPU: @@ -266,15 +265,16 @@ If the relevant grace-period kthread has been unable to run prior to the stall warning, as was the case in the "All QSes seen" line above, the following additional line is printed: - kthread starved for 23807 jiffies! g7073 c7072 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1 + kthread starved for 23807 jiffies! g7075 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x1 ->cpu=5 Starving the grace-period kthreads of CPU time can of course result in RCU CPU stall warnings even when all CPUs and tasks have passed -through the required quiescent states. The "g" and "c" numbers flag the -number of the last grace period started and completed, respectively, -the "f" precedes the ->gp_flags command to the grace-period kthread, -the "RCU_GP_WAIT_FQS" indicates that the kthread is waiting for a short -timeout, and the "state" precedes value of the task_struct ->state field. +through the required quiescent states. The "g" number shows the current +grace-period sequence number, the "f" precedes the ->gp_flags command +to the grace-period kthread, the "RCU_GP_WAIT_FQS" indicates that the +kthread is waiting for a short timeout, the "state" precedes value of the +task_struct ->state field, and the "cpu" indicates that the grace-period +kthread last ran on CPU 5. Multiple Warnings From One Stall diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt index 65eb856526b7..c2a7facf7ff9 100644 --- a/Documentation/RCU/whatisRCU.txt +++ b/Documentation/RCU/whatisRCU.txt @@ -588,6 +588,7 @@ It is extremely simple: void synchronize_rcu(void) { write_lock(&rcu_gp_mutex); + smp_mb__after_spinlock(); write_unlock(&rcu_gp_mutex); } @@ -609,12 +610,15 @@ don't forget about them when submitting patches making use of RCU!] The rcu_read_lock() and rcu_read_unlock() primitive read-acquire and release a global reader-writer lock. The synchronize_rcu() -primitive write-acquires this same lock, then immediately releases -it. This means that once synchronize_rcu() exits, all RCU read-side -critical sections that were in progress before synchronize_rcu() was -called are guaranteed to have completed -- there is no way that -synchronize_rcu() would have been able to write-acquire the lock -otherwise. +primitive write-acquires this same lock, then releases it. This means +that once synchronize_rcu() exits, all RCU read-side critical sections +that were in progress before synchronize_rcu() was called are guaranteed +to have completed -- there is no way that synchronize_rcu() would have +been able to write-acquire the lock otherwise. The smp_mb__after_spinlock() +promotes synchronize_rcu() to a full memory barrier in compliance with +the "Memory-Barrier Guarantees" listed in: + + Documentation/RCU/Design/Requirements/Requirements.html. It is possible to nest rcu_read_lock(), since reader-writer locks may be recursively acquired. Note also that rcu_read_lock() is immune @@ -816,11 +820,13 @@ RCU list traversal: list_next_rcu list_for_each_entry_rcu list_for_each_entry_continue_rcu + list_for_each_entry_from_rcu hlist_first_rcu hlist_next_rcu hlist_pprev_rcu hlist_for_each_entry_rcu hlist_for_each_entry_rcu_bh + hlist_for_each_entry_from_rcu hlist_for_each_entry_continue_rcu hlist_for_each_entry_continue_rcu_bh hlist_nulls_first_rcu diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 533ff5c68970..c370f5f0eb38 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3632,8 +3632,8 @@ Set time (s) after boot for CPU-hotplug testing. rcutorture.onoff_interval= [KNL] - Set time (s) between CPU-hotplug operations, or - zero to disable CPU-hotplug testing. + Set time (jiffies) between CPU-hotplug operations, + or zero to disable CPU-hotplug testing. rcutorture.shuffle_interval= [KNL] Set task-shuffle interval (s). Shuffling tasks |
